22,496 results on '"Reproducibility"'
Search Results
2. MemXCT: Design, Optimization, Scaling, and Reproducibility of X-Ray Tomography Imaging
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Doga Gursoy, Simon Garcia de Gonzalo, Rajkumar Kettimuthu, Wen-mei W. Hwu, Ian Foster, Mert Hidayetoglu, Tekin Bicer, and Bin Ren
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Reproducibility ,Optics ,Computational Theory and Mathematics ,Hardware and Architecture ,Computer science ,business.industry ,Signal Processing ,X-ray ,Tomography ,business ,Scaling - Published
- 2022
3. Non-contact monitoring of the depth temperature profile for medical laser scanning technologies
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Jure Kosir, Matija Jezeršek, and Daniele Vella
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udc:61:543.572.3(045) ,termografija ,Materials science ,Laser scanning ,Infrared ,engineering ,lcsh:Medicine ,01 natural sciences ,Article ,law.invention ,010309 optics ,03 medical and health sciences ,0302 clinical medicine ,Optics ,Engineering ,law ,biomedical engineering ,0103 physical sciences ,Thermal ,Miniaturization ,prenos toplote v tkivu ,lcsh:Science ,Overheating (electricity) ,Reproducibility ,Multidisciplinary ,business.industry ,lcsh:R ,Laser ,thermography ,depth temperatur profile ,heat transfer in biological tissue ,030220 oncology & carcinogenesis ,Thermography ,lcsh:Q ,temperaturni profil ,business ,Biomedical engineering - Abstract
Medical treatments such as high-intensity focused ultrasound, hyperthermic laser lipolysis or radiofrequency are employed as a minimally invasive alternatives for targeted tissue therapies. The increased temperature of the tissue triggers various thermal effects and leads to an unavoidable damage. As targeted tissues are generally located below the surface, various approaches are utilized to prevent skin layers from overheating and irreparable thermal damages. These procedures are often accompanied by cooling systems and protective layers accounting for a non-trivial detection of the subsurface temperature peak. Here, we show a temperature peak estimation method based on infrared thermography recording of the surface temperature evolution coupled with a thermal-diffusion-based model and a time-dependent data matching algorithm. The performance of the newly developed method was further showcased by employing hyperthermic laser lipolysis on an ex-vivo porcine fat tissue. Deviations of the estimated peak temperature remained below 1 °C, as validated by simultaneous measurement of depth temperature field within the tissue. Reconstruction of the depth profile shows a good reproducibility of the real temperature distribution with a small deviation of the peak temperature position. A thermal camera in combination with the time-dependent matching bears the scope for non-contact monitoring of the depth temperature profile as fast as 30 s. The latest demand for miniaturization of thermal cameras provides the possibility to embed the model in portable thermal scanners or medical laser technologies for improving safety and efficiency.
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- 2023
4. Can the measured angle ABC on the lateral projection of the knee be used to determine the tube angulation for an optimum skyline projection?
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L.J.Y. Seah, E.C.-P. Chua, D. Seow, L.H. Sng, and D. Mahmood
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Adult ,Orthodontics ,Skyline ,Reproducibility ,Skyline projection ,Knee Joint ,business.industry ,Intraclass correlation ,Radiography ,Reproducibility of Results ,Patella ,Middle Aged ,Tilt (optics) ,Humans ,Knee ,Radiology, Nuclear Medicine and imaging ,Podiatry ,Projection (set theory) ,business ,Reliability (statistics) ,Aged ,Retrospective Studies ,Mathematics - Abstract
Introduction The current technique of angulating for a skyline knee projection relies heavily on the radiographer's estimation of the patella tilt, rendering it subjective and prone to errors. This study therefore aims to (i) examine the correlation between angle ABC measured on the lateral X-ray image and skyline angulation (measured in degrees) and (ii) determine the inter-rater reliability of angle ABC measurements. Methods 145 sets of lateral and skyline X-ray images from patients aged 40–70 years old were retrospectively analysed. Angle ABC was measured using prominent landmarks such as the trochlear sulcus, tibial tuberosity and the anterior border of the patella on the lateral knee radiograph. It was then retrospectively compared with the skyline tube angulations to identify any correlation between the two. An inter-rater reliability test was also conducted using the intraclass correlation coefficient (ICC) to determine the reproducibility of the measurement method. Results A weak correlation was found between angle ABC and skyline angulation (r = 0.1, p = 0.25). The proposed method of measurement shows good inter-rater reliability (ICC = 0.81, 95% CI: 0.77 to 0.84). Conclusion There is insufficient evidence to indicate a correlation between angle ABC and skyline angulation. However, angle ABC can be reliably measured, implying the replicability of the measurement method for other purposes. Implications for practice The proposed measurement method of angle ABC on the lateral view could have future applications in other areas such as in the measurement of patellofemoral alignment and trochlear morphology.
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- 2022
5. Skin measurement devices to assess skin quality
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Joris A van Dongen, Eimear O' Sullivan, Mirte Langeveld, Lara S van de Lande, Berend van der Lei, and Plastic and Reconstructive Surgery and Hand Surgery
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medicine.medical_specialty ,MELANIN ,media_common.quotation_subject ,skin rejuvenation ,Skin Pigmentation ,Dermatology ,NONINVASIVE INSTRUMENTS ,Skin Aging ,facial surgery ,systematic review ,plastic surgery ,REPRODUCIBILITY ,skin quality ,medicine ,Humans ,measurement tools ,COLOR ,Medical physics ,Quality (business) ,MEXAMETER((R)) ,Reliability (statistics) ,media_common ,ERYTHEMA ,Reproducibility ,integumentary system ,business.industry ,Reproducibility of Results ,Construct validity ,REFLECTANCE SPECTROSCOPY ,Convergent validity ,Skin color ,PIGMENTATION ,business ,Skin elasticity - Abstract
Background: Many treatments aim to slow down or reverse the visible signs of skin aging and thereby improve skin quality. Measurement devices are frequently employed to measure the effects of these treatments to improve skin quality, for example, skin elasticity, color, and texture. However, it remains unknown which of these devices is most reliable and valid. Materials and methods: MEDLINE, Embase, Cochrane Central, Web of Science, and Google Scholar databases were searched. Instruments were scored on reporting construct validity by means of convergent validity, interobserver, intraobserver, and interinstrument reliability. Results: For the evaluation of skin color, 11 studies were included describing 16 measurement devices, analyzing 3172 subjects. The most reliable device for skin color assessment is the Minolta Chromameter CR-300 due to good interobserver, intraobserver, and interinstrument reliability. For skin elasticity, seven studies assessed nine types of devices analyzing 290 subjects in total. No intra and interobserver reliability was reported. Skin texture was assessed in two studies evaluating 72 subjects using three different types of measurement devices. The PRIMOS device reported excellent intra and interobserver reliability. None of the included reviewed devices could be determined to be valid based on construct validity. Conclusion: The most reliable devices to evaluate skin color and texture in ordinary skin were, respectively, the Minolta Chromameter and PRIMOS. No reliable device is available to measure skin elasticity in ordinary skin and none of the included devices could be determined to be designated as valid.
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- 2022
6. Sources of variation in multicenter rectal MRI data and their effect on radiomics feature reproducibility
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Simon van Kranen, Gerlof Bosma, Frans C. H. Bakers, Shira de Bie, Remy W F Geenen, Cornelis J Veeken, Gerald Peterson, Francesca Castagnoli, Doenja M. J. Lambregts, Najim El Khababi, Sander Roberti, Regina G. H. Beets-Tan, Roy F. A. Vliegen, Joost J. M. van Griethuysen, Niels W. Schurink, Vincent C. Cappendijk, Nino Bogveradze, P.A. Neijenhuis, RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy, Beeldvorming, School Office GROW, and MUMC+: DA BV Medisch Specialisten Radiologie (9)
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Reproducibility of results ,medicine.medical_specialty ,Reproducibility ,Intraclass correlation ,business.industry ,PREDICTION ,Feature extraction ,Image processing ,Rectal neoplasms ,General Medicine ,Repeatability ,CANCER ,Multicenter study ,Magnetic resonance imaging ,Feature (computer vision) ,Linear regression ,medicine ,Radiology, Nuclear Medicine and imaging ,Segmentation ,Computer-assisted ,Radiology ,Nuclear medicine ,business ,REPEATABILITY - Abstract
Objectives To investigate sources of variation in a multicenter rectal cancer MRI dataset focusing on hardware and image acquisition, segmentation methodology, and radiomics feature extraction software. Methods T2W and DWI/ADC MRIs from 649 rectal cancer patients were retrospectively acquired in 9 centers. Fifty-two imaging features (14 first-order/6 shape/32 higher-order) were extracted from each scan using whole-volume (expert/non-expert) and single-slice segmentations using two different software packages (PyRadiomics/CapTk). Influence of hardware, acquisition, and patient-intrinsic factors (age/gender/cTN-stage) on ADC was assessed using linear regression. Feature reproducibility was assessed between segmentation methods and software packages using the intraclass correlation coefficient. Results Image features differed significantly (p Conclusions Significant variations are present in multicenter MRI data, particularly related to differences in hardware and acquisition, which will likely negatively influence subsequent analysis if not corrected for. Segmentation variations had a minor impact when using whole volume segmentations. Between software packages, higher-order features were less reproducible and caution is warranted when implementing these in prediction models. Key Points • Features derived from T2W-MRI and in particular ADC differ significantly between centers when performing multicenter data analysis. • Variations in ADC are mainly (> 60%) caused by hardware and image acquisition differences and less so ( • Features derived using different image segmentations (expert/non-expert) were reproducible, provided that whole-volume segmentations were used. When using different feature extraction software packages with similar settings, higher-order features were less reproducible.
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- 2022
7. Radiomics Analysis for Predicting Malignant Potential of Intraductal Papillary Mucinous Neoplasms of the Pancreas: Comparison of CT and MRI
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Hai-Bin Shi, Shaofeng Duan, Ming Lu, Hongyuan Shi, Chen Wang, Shenhao Cheng, and Qing Xu
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Reproducibility ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Intraclass correlation ,Pancreatic Intraductal Neoplasms ,Reproducibility of Results ,Interobserver reproducibility ,Magnetic resonance imaging ,Logistic regression ,Magnetic Resonance Imaging ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Radiomics ,030220 oncology & carcinogenesis ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Radiology ,Tomography, X-Ray Computed ,business ,Pancreas ,Selection operator - Abstract
To compare the performance of CT and MRI radiomics for predicting the malignant potential of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas, and to investigate their value compared to the revised 2017 international consensus Fukuoka guidelines.Sixty patients with surgically confirmed IPMNs (37 malignant and 23 benign) were included. Radiomics features were extracted from arterial and venous phase images of CT and T2-weighted images of MRI, respectively. Intraclass correlation coefficients for the radiomics features were calculated to assess the interobserver reproducibility. The least absolute shrinkage and selection operator algorithm was used for feature selection. Radiomics models were constructed based on selected features with logistic regression (LR) and support vector machine (SVM). A clinical and imaging model was constructed based on independent predictors of the revised 2017 Fukuoka guidelines determined in multivariate logistic regression with forward elimination.The reproducibility of MRI radiomics features was higher than that of CT radiomics features, regardless of arterial or venous phase features (all p0.001). MRI radiomics models achieved improved AUCs (0.879 with LR and 0.940 with SVM, respectively), than that of CT radiomics models (0.811 with LR and 0.864 with SVM, respectively). All radiomics models provided better predictive performance than the clinical and imaging model (AUC = 0.764).The MRI radiomics models with higher reproducibility radiomics features performed better than CT radiomics models for predicting the malignant potential of IPMNs. The performance of radiomics models was superior to the clinical and imaging model based on Fukuoka guidelines.
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- 2022
8. Modulus of Elasticity of Elastic Tubes Used in Neuromuscular Rehabilitation Programs
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Bernardo Neme Ide, Thaís Branquinho de Araújo, Fernando Sousa Honorato, José de Jesus Soares Reis, Thiago Lucena Reis, Thaís Lucena Reis, Hugo de Luca Corrêa, Andrea Lucena Reis, Rodrigo Vanerson Passos Neves, Lucas Soares de Aguiar, Thiago Santos Rosa, Victor Lopes Silva, and Lysleine Alves Deus
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Reproducibility ,Intraclass correlation ,business.industry ,Rehabilitation ,Biophysics ,Reproducibility of Results ,Resistance Training ,Physical Therapy, Sports Therapy and Rehabilitation ,Context (language use) ,Young's modulus ,Structural engineering ,Elasticity ,Pearson product-moment correlation coefficient ,symbols.namesake ,Elastic Modulus ,Linear regression ,symbols ,Humans ,Orthopedics and Sports Medicine ,business ,Exercise ,Elastic modulus ,Student's t-test ,Mathematics - Abstract
Context: The elastic tubes have been used for clinical rehabilitation programs in which exercises are performed with submaximal intensities due to the difficulty in the measure the applied force. The authors aimed to quantify the elastic constant of elastic tubes used in neuromuscular rehabilitation programs predicting the force related to elastic tube elongation. A force test was performed by stretching the elastic tubes to determine the relationship between force and elongation. Eight elastic tubes with progressive levels of resistance represented by colors (yellow, red, blue, gray, black, grape, purple, and gold—low to higher resistance) were used. Design: Experimental. Methods: The test and retest were compared using the paired t test. The agreement and reliability between the test versus retest of pooled means colors were analyzed by plotting the Bland–Altman graph and intraclass correlation coefficient and the coefficient of variation. Pearson correlation was used to verify the validity between measurements. Results: The force values generated from the elastic tube elongation increase according to the color and thickness of elastic tubes with a strong and significant association between them (P P Conclusions: The force could be quantified according to elastic tube length variation by the linear regression equation with reproducibility. It gives greater measurement precision and better training load control when using elastic tubes in strength training programs.
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- 2022
9. Label-free photoelectrochemical sensor based on 2D/2D ZnIn2S4/g-C3N4 heterojunction for the efficient and sensitive detection of bisphenol A
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Chen Yuan, Qiaowei Chen, and Chunyang Zhai
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Detection limit ,Bisphenol A ,Reproducibility ,Materials science ,business.industry ,Visible light irradiation ,Heterojunction ,General Chemistry ,chemistry.chemical_compound ,chemistry ,Electrode ,Optoelectronics ,business ,Label free - Abstract
Photoelectrochemical (PEC) sensor is an emerging technology in analysis as the advantage of fast response, high sensitivity and uncomplicated operation. In this study, an effective label-free PEC sensor for bisphenol A (BPA) detecting is constructed, in which ZnIn2S4/g-C3N4 heterojunction is prepared via a simple hydrothermal method. The characterization outcomes display that the formation of p-n heterojunction helps for promoting the separation efficiency of photo-generated carrier. Under visible light irradiation, the ZnIn2S4/g-C3N4 modified electrode exhibits broader liner range from 0.05 mmol/L to 30 mmol/L and lower detection limit of 0.016 μmol/L (S/N=3) with remarkable stability and reproducibility of detection BPA under visible light irradiation. Furthermore, the constructed PEC sensor displays favorable potential for detection of BPA in practical applications.
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- 2022
10. The accuracy and reliability of WebCeph for cephalometric analysis
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Sarah A Nabbat, Yassir A. Yassir, and Aya R. Salman
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Orthodontics ,Cephalometric analysis ,Medicine (General) ,Reproducibility ,business.industry ,Intraclass correlation ,Cephalometric software ,General Medicine ,WebCeph ,Plot (graphics) ,R5-920 ,Software ,Linear regression ,Orthodontic ,business ,Cephalogram ,Reliability (statistics) ,Mathematics - Abstract
الملخص: أهداف البحث: تقارن هذه الدراسة دقة وموثوقية ''ويبسيف'' (برنامج قائم على الويب لتحليل قياس الرأس) مع برنامج الكمبيوتر أوتوكاد. طرق البحث: تم تحليل عينة من مخططات رأسية جانبية رقمية لـ ٥٠ مريضا لتقويم الأسنان قبل المعالجة باستخدام برنامج ''ويبسيف'' وبرنامج أوتوكاد (كمقياس قياسي). في كل مخطط رأسي، تم وضع علامة على ١٧ معلما و١١ قياسا وتنفيذها كمعلمات للهيكل العظمي والأسنان والأنسجة الرخوة. استخدمنا ست زوايا وخمس قياسات خطية. كما تم استخدام اختبار تي المقترن لتقييم التحيز المنهجي. واستخدام تحليل الارتباط داخل الطبقة واختطاط بلاند-ألتمان مع تحليل الانحدار الخطي لتقييم التوافق بين الطريقتين. النتائج: كانت هناك موثوقية كافية للقياسات باستخدام ''ويبسيف'' وأوتوكاد. أظهر اختبار تي المقترن فروق ذات دلالة إحصائية لخمس زوايا واثنين من القياسات الخطية. كما أظهر اختبار الارتباط داخل الطبقة بين ''ويبسيف'' وأوتوكاد توافقا جيدا جدا إلى ممتاز لجميع القياسات باستثناء القاطعة السفلية لزاوية مستوى الفك السفلي. وأظهر اختطاط بلاند-ألتمان حدا مقبولا نسبيا للاتفاق لثلاث زواويا واثنين من القياسات الخطية فقط، وكشف تحليل الانحدار الخطي عن تحيز نسبي كبير بين الطريقتين لأربع زوايا وخط تجميل الشفة العليا. وتم تحسين التحيز المنهجي ومستوى الاتفاق باستخدام ''ويبسيف'' شبه التلقائي. الاستنتاجات: هناك مشاكل مختلفة متأصلة في ''ويبسيف'' التلقائي مثل ضعف تحديد المعالم / تتبع الأنسجة الرخوة وعدم اتساق القياسات. يمكن لـ ''ويبسيف'' شبه التلقائي التغلب على بعض قيود ''ويبسيف'' التلقائي، الذي يجب استخدامه لتحليل قياس الرأس بقدر كبير من الحذر. Abstract: Objective: This study compares the accuracy and reliability of WebCeph (web-based program for cephalometric analysis) with the AutoCAD computer software. Materials and methods: A sample of pretreatment digital lateral cephalograms of 50 orthodontic patients was analysed with WebCeph and AutoCAD software (as a standard measure). On each cephalogram, 17 landmarks and 11 measurements were marked and performed as skeletal, dental, and soft–tissue parameters. We used six angular and five linear measurements. A paired t-test was used to assess the systematic bias. The intraclass correlation coefficient (ICC) and Bland–Altman plot with linear regression analysis were used to assess the agreement between the two methods. Results: There was adequate reproducibility for the measurements with both WebCeph and AutoCAD. The paired t-test showed statistically significant differences for five angular and two linear measurements (P
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- 2022
11. Thermally assisted IRSL and VSL measurements of display glass from mobile phones for retrospective dosimetry
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Michael Discher, Hyoungtaek Kim, and Jungil Lee
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Reproducibility ,Dosimeter ,Materials science ,Optically stimulated luminescence ,business.industry ,TK9001-9401 ,Thermally assisted OSL ,Display glass of mobile phones ,Thermoluminescence ,Retrospective dosimetry ,Dosimetric properties ,Nuclear Energy and Engineering ,Absorbed dose ,Optoelectronics ,Dosimetry ,Nuclear engineering. Atomic power ,Irradiation ,business ,Luminescence - Abstract
Investigations of retrospective dosimetry have shown that components of mobile phones are suitable as emergency dosimeters in case of radiological incidents. For physical dosimetry, components can be read out using optically stimulated luminescence (OSL), thermoluminescence (TL) and phototransferred thermoluminescence (PTTL) methods to determine the absorbed dose. This paper deals with a feasibility study of display glass from modern mobile phones that are measured by thermally assisted (Ta) optically stimulated luminescence. Violet (VSL, 405 nm) and infrared (IRSL, 850 nm) LEDs were used for optical stimulation and two protocols (Ta-VSL and Ta-IRSL) were tested. The aim was to systematically investigate the luminescence properties, compare the results to blue stimulated Ta-BSL protocol (458 nm) and to develop a robust measurement protocol for the usage as an emergency dosimeter after an incident with ionizing radiation. First, the native signals were measured to calculate the zero dose signal. Next, the reproducibility and dose response of the luminescence signals were analyzed. Finally, the signal stability was tested after the storage of irradiated samples at room temperature. In general, the developed Ta-IRSL and Ta-VSL protocols indicate usability, however, further research is needed to test the potential of a new protocol for physical retrospective dosimetry.
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- 2022
12. Comparison of Hyperpolarized 3He and 129Xe MR Imaging in Cystic Fibrosis Patients
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Kun Qing, F. William Hersman, Jamie Mata, Iulian C. Ruset, Talissa A. Altes, John P. Mugler, Craig H. Meyer, Robert P. Thomen, Ummul Afia Shammi, and Michelle Felicia D'Alessandro
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Reproducibility ,Lung ,medicine.diagnostic_test ,business.industry ,Magnetic resonance imaging ,computer.software_genre ,medicine.disease ,Cystic fibrosis ,Mr imaging ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Voxel ,030220 oncology & carcinogenesis ,medicine ,Radiology, Nuclear Medicine and imaging ,In patient ,Nuclear medicine ,business ,computer ,Lung function - Abstract
PURPOSE In this study, we compared hyperpolarized 3He and 129Xe images from patients with cystic fibrosis using two commonly applied magnetic resonance sequences, standard gradient echo (GRE) and balanced steady-state free precession (TrueFISP) to quantify regional similarities and differences in signal distribution and defect analysis. MATERIALS AND METHODS Ten patients (7M/3F) with cystic fibrosis underwent hyperpolarized gas MR imaging with both 3He and 129Xe. Six had MRI with both GRE, and TrueFISP sequences and four patients had only GRE sequence but not TrueFISP. Ventilation defect percentages (VDPs) were calculated as lung voxels with
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- 2022
13. Measurement of Plaque Characteristics Using Coronary Computed Tomography Angiography: Achieving High Interobserver Performance
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G.B. John Mancini, Eunice Yeoh, Craig Kamimura, C. David Mazer, and Arnold Ryomoto
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Reproducibility ,Training set ,Correlation coefficient ,business.industry ,Operating procedures ,Coronary computed tomography angiography ,medicine.anatomical_structure ,Standard error ,Observer performance ,RC666-701 ,medicine ,Diseases of the circulatory (Cardiovascular) system ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine ,Artery - Abstract
Background: Coronary computed tomography angiography (CCTA) is used to assess plaque characteristics, remodelling, and progression and regression. Few papers address standard operating procedures that ensure achievement of high interobserver reproducibility. Moreover, assessment of coronary artery bypass grafts has not been reported. Methods: A training set of images was created of native coronary segments, spanning the full range of atheromatous disease from normal to severe, excluding totally occluded segments, and including segments with or without calcification (n = 24) and completely normal-appearing bypass grafts (n = 16). Three observers used a validated software program during a training phase to establish standard operating procedures and then to achieve high intraobserver performance based on Pearson’s correlation coefficient. Subsequently, interobserver variability for the laboratory as a whole was determined with a focus on measures of plaque volume, low- attenuation plaque (LAP), mixed plaque (MP), and calcified plaque (CP). Results: We found no substantive differences in analytical issues between grafts and native vessels and emphasize the aggregated data. The range of mean total plaque percent was approximately 55% of total vessel volume with maximal interobserver mean absolute differences of 2% or less. Percent of LAP, MP, and CP demonstrated interobserver standard errors of 1% to 2% and interobserver mean absolute differences of 0% to 1%. Pearson’s correlations were all highly significant and ranged from 0.969 to 0.999. Conclusions: CCTA provides a rich diversity of measures of atherosclerosis in coronary and bypass segments that are highly reproducible with experience and adherence to standard operating procedures. Résumé: Introduction: L’angiographie cardiaque par tomodensitométrie (TDM) est utilisée pour évaluer les caractéristiques, le remodelage, la progression et la régression de la plaque. Peu d’articles portent sur les procédures opérationnelles normalisées qui permettent d’atteindre une reproductibilité inter-observateurs élevée. De plus, les greffons de pontage aorto-coronarien n’ont pas fait l’objet d’évaluation. Méthodologie: Un ensemble de formation composé d’images de segments d’artères coronaires natives couvrant l’ensemble de la maladie athéromateuse, c’est-à-dire de normale à sérieuse, à l’exclusion des segments totalement obstrués, mais y compris les segments calcifiés ou non (n = 24) et les greffons de pontage qui apparaissent complètement normaux (n = 16) a été créé. Trois observateurs ont utilisé un programme informatique validé durant la phase de formation pour établir des procédures opérationnelles normalisées et ensuite pour atteindre une performance intra-observateurs élevée en fonction du coefficient de corrélation de Pearson. Subséquemment, la variabilité inter-observateurs du laboratoire dans son ensemble a été déterminée plus particulièrement par les mesures du volume de la plaque, la plaque de faible atténuation (PFA), la plaque mixte (PM) et la plaque calcifiée (PC). Résultats: Nous n’avons constaté aucune différence dans les difficultés analytiques entre les greffons et les vaisseaux natifs et faisons valoir les données regroupées. La fourchette du pourcentage total moyen de la plaque était approximativement de 55 % du volume total du vaisseau avec des différences inter-observateurs absolues moyennes maximales de 2 % ou moins. Le pourcentage de la PFA, de la PM et de la PC a démontré des erreurs types inter-observateurs de 1 % à 2 % et des différences absolues moyennes inter-observateurs de 0 % à 1 %. Les corrélations de Pearson étaient toutes hautement significatives et allaient de 0,969 à 0,999. Conclusions: La TDM offre une riche diversité de mesures de l’athérosclérose dans les segments d’artères coronaires et de pontage qui, avec l’expérience et le respect des procédures opérationnelles normalisées, sont très reproductibles.
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- 2022
14. Quantification of Soy-Derived Ingredients in Model Bread and Frankfurter Matrices with an Optimized Liquid Chromatography–Tandem Mass Spectrometry External Standard Calibration Workflow
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Joseph L. Baumert, Jenna Krager, and Melanie L. Downs
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Reproducibility ,Chemistry ,business.industry ,Reproducibility of Results ,Bread ,Replicate ,Microbiology ,Workflow ,Standard curve ,Ingredient ,Matrix (mathematics) ,Tandem Mass Spectrometry ,Calibration ,Protein purification ,Food processing ,Food science ,business ,Soy protein ,Food Analysis ,Chromatography, Liquid ,Food Science - Abstract
The detection and quantification of soy protein is important for food allergen management and identifying the presence of undeclared soy proteins. Heat processing and matrix interactions can affect the accuracy of allergen detection methods. The sensitivity of enzyme-linked immunosorbent assay methods can be compromised if protein epitopes are modified during processing. Therefore, a mass spectrometry (MS)-based method was evaluated for the recovery of total soy protein in incurred matrices. MS-based quantification of total soy protein was assessed by using a combination of external and internal standards. The reproducibility of the standard curves was investigated by comparing within-day and among-day variation. Incurred samples were prepared using bread and frankfurters as model food matrices. Several soy-derived ingredients were used to prepare the matrices with varying levels of soy protein (1, 10, 50, or 100 ppm of total soy protein). A pooled standard curve was used to estimate the total soy protein concentration of the incurred food matrices and the percent total protein recovery. The variation of replicate standard curves between days and among all days was not significant. The differences in slopes obtained from replicate standards run on different days were minimal. The most influential factor on the quantitative protein recovery in incurred samples was the effect of the physical matrix structure on protein extraction. The lowest percent protein recoveries, less than 50%, were calculated for uncooked matrices. The cooked matrices had percentage recoveries between 50 and 150% for all total soy protein levels. Other factors, such as type of ingredient, were determined to be not as impactful on recovery. The MS method described in this study was able to provide sensitive detection and accurate quantification of total soy protein from various soy-derived ingredients present in processed food matrices.
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- 2022
15. Reproducibility of quantitative flow ratio: the QREP study
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Hernán Mejía-Rentería, Niels Ramsing Holm, Janusz Kochman, Tommy Liu, Andrea Erriquez, Gianluca Campo, Łukasz Kołtowski, Yimin Zhang, Martin Sejr-Hansen, Javier Escaned, Jelmer Westra, Lone Juul Hune Mogensen, Jakob Hjort, Shengxian Tu, Birgitte Krogsgaard Andersen, Evald Høj Christiansen, and Ashkan Eftekhari
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stable angina ,fractional flow reserve, QCA, stable angina ,Fractional Flow Reserve, Myocardial/physiology ,Coefficient of variation ,Coronary Vessels/diagnostic imaging ,Interobserver reproducibility ,Coronary stenosis ,Coronary Angiography ,Severity of Illness Index ,ANGIOGRAPHY ,NO ,Clinical Research ,Predictive Value of Tests ,Secondary analysis ,Humans ,Medicine ,DIAGNOSTIC-ACCURACY ,fractional flow reserve ,Reproducibility ,QCA ,business.industry ,Coronary Stenosis ,Reproducibility of Results ,Coronary Vessels ,Fractional Flow Reserve, Myocardial ,Coronary Stenosis/diagnostic imaging ,Flow ratio ,Invasive coronary angiography ,RESERVE ,Cardiology and Cardiovascular Medicine ,business ,Nuclear medicine - Abstract
Background: Quantitative flow ratio (QFR) is a tool for physiological lesion assessment based on invasive coronary angiography.Aims: We aimed to assess the reproducibility of QFR computed from the same angiograms as assessed by multiple observers from different, international sites.Methods: We included 50 patients previously enrolled in dedicated QFR studies. QFR was computed twice, one month apart by five blinded observers. The main analysis was the coefficient of variation (CV) as a measure of infra- and inter-observer reproducibility. Key secondary analysis was the identification of clinical and procedural characteristics predicting reproducibility.Results: The intra-observer CV ranged from 2.3% (1.5-2.8) to 10.2% (6.6-12.0) among the observers. The inter-observer CV was 9.4% (8.0-10.5). The QFR observer, low angiographic quality, and low fractional flow reserve (FFR) were independent predictors of a large absolute difference between repeated QFR measurements defined as a difference larger than the median difference (>0.03).Conclusions: The inter- and intra-observer reproducibility for QFR computed from the same angiograms ranged from high to poor among multiple observers from different sites with an average agreement of 0.01 +/--0.08 for repeated measurements. The reproducibility was dependent on the observer, angiographic quality and the coronary artery stenosis severity as assessed by FFR.
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- 2022
16. Variability and reliability of 2-dimensional vs. 3-dimensional glenoid version measurements with 3-dimensional preoperative planning software
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Alex Greene, Josef K. Eichinger, Jared J. Reid, Richard J. Friedman, and Bryce F. Kunkle
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Reproducibility ,Glenoid Cavity ,Shoulder Joint ,business.industry ,Shoulders ,Intraclass correlation ,medicine.medical_treatment ,Reproducibility of Results ,General Medicine ,Arthroplasty ,Confidence interval ,Scapula ,Imaging, Three-Dimensional ,Software ,Outlier ,medicine ,Humans ,Orthopedics and Sports Medicine ,Surgery ,business ,Nuclear medicine ,Reliability (statistics) - Abstract
BACKGROUND Preoperative planning for total shoulder arthroplasty (TSA) may change according to the measured degree of glenoid version. Both 2-dimensional (2D) and 3-dimensional (3D) computed tomographic (CT) scans are used to measure glenoid version, with no consensus on which method is more accurate. However, it is generally accepted that 3D measurements are more reliable, yet most 3D reconstruction software currently in clinical use have never been directly compared to 2D. The purpose of this study is to directly compare 2D and 3D glenoid version measurements and determine the differences between the two. METHODS CT scans were performed preoperatively on 315 shoulders undergoing either anatomic or reverse TSA. 2D measurements of glenoid version were obtained manually using the Friedman method, whereas 3D measurements were obtained using the Equinoxe Planning Application (Exactech Inc.) 3D-reconstruction software. Negative version values indicate retroversion, whereas positive values indicate anteversion. Two observers collected the 2D measurements 2 separate times, and intra- and interobserver measurements were calculated. Groups were compared for variability using intraclass correlation coefficients (ICCs), and for differences in sample means using Student t tests. Additionally, samples were stratified by version value in order to better understand the potential sources of error between measurement techniques. RESULTS For the 2D measurements, intraobserver variability indicated excellent reproducibility for both observer 1 (ICC = 0.928, 95% confidence interval [CI] 0.911-0.942) and observer 2 (ICC = 0.964, 95% CI 0.955-0.971). Interobserver variability measurements also indicated excellent reproducibility (ICC = 0.915, 95% CI 0.778-0.956). The overall 2D version measurement average (-4.9° ± 10.3°) was significantly less retroverted than the 3D measurement average (-8.4° ± 9.1°) (P < .001), with 3D measurements yielding a more retroverted value 73% of the time. When stratified on the basis of version value with outliers excluded, there was no significant difference in the distribution of high-error samples within the data. DISCUSSION There was excellent reproducibility between the 2 observers in terms of both intra- and interobserver variability. The 3D measurement techniques were significantly more likely to return a more retroverted measurement, and high-error samples were evenly distributed throughout the data, indicating that there were no discernable trends in the degree of error observed. Shoulder surgeons should be aware that different glenoid version measurement strategies can yield different version measurements, as these can affect preoperative planning and surgeon decision making.
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- 2022
17. Validation and reproducibility of a semi-qualitative food frequency questionnaire for assessment of sodium intake in Iranian population
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Noushin Mohammadifard, Ali Reza Khosravi, Awat Feizi, Nizal Sarrafzadegan, Narges Grau, Ahmad Esmaillzadeh, and Zahra Abdollahi
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Adult ,RC620-627 ,Adolescent ,Food frequency questionnaire ,Medicine (miscellaneous) ,Iran ,Diet Surveys ,Validity ,Iranian population ,Young Adult ,Environmental health ,Surveys and Questionnaires ,Vegetables ,Medicine ,Humans ,TX341-641 ,Child ,Nutritional diseases. Deficiency diseases ,Reproducibility ,Nutrition and Dietetics ,Salt intake ,business.industry ,Nutrition. Foods and food supply ,Research ,Reproducibility of Results ,Sodium, Dietary ,Reliability ,Sodium intake ,Diet ,Dietary sodium ,business ,Energy Intake - Abstract
Background Few semi-quantitative food frequency questionnaires (SFFQ)s has yet been developed to assess sodium intake in Middle East region. This study was performed to validate a SFFQ for assessment of sodium consumption and food groups΄ contribution to sodium intake. Methods This study was performed on 219 healthy participants including 113 adults aged ≥19 years and 106 children aged 6–18 years in Isfahan, Iran. They were administered two SFFQ at the beginning and after 1 year to evaluate the reproducibility. The validity of SFFQ for assessment of sodium intake was compared with 24-h urine sodium and twelve 24-h dietary recalls which were completed monthly during a year as two standard methods. Results Correlation coefficient between the contribution of food groups to sodium intake based on SFFQ and 24-h dietary recalls varied from 0.04 for legumes (P = 0.667) to 0.47 for added salt (P P Conclusions The SFFQ was a relatively valid and reproducible method for estimating sodium intake. Combination of this SFFQ with a valid prediction of 24-h urinary sodium excretion can be useful in achieving more accurate results.
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- 2022
18. Measurement uncertainty analysis of radiophotoluminescent glass dosimeter reader system based on GD-352M for estimation of protection quantity
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Byeong Ryong Park, Hyun Kim, Wi Ho Ha, Yong Kyun Kim, Jaeryong Yoo, Gyu Seok Cho, Won Il Jang, Seongjae Jang, Jae Seok Kim, and Insu Chang
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Radiophotoluminescent glass dosimeter (RPLGD) ,Reproducibility ,Dosimeter ,Computer science ,business.industry ,Measurement uncertainty ,Nuclear engineering ,Dosimetric characteristics ,TK9001-9401 ,Filter (signal processing) ,GD-352M ,Nuclear Energy and Engineering ,Nuclear engineering. Atomic power ,Angular dependence ,Radiation protection ,business ,Quality assurance ,Regression curve - Abstract
At the Korea Institute of Radiological and Medical Sciences, physical human phantoms were developed to evaluate various radiation protection quantities, based on the mesh-type reference computational phantoms of the International Commission on Radiological Protection. The physical human phantoms were fabricated such that a radiophotoluminescent glass dosimeter (RPLGD) with a Tin filter, namely GD-352M, could be inserted into them. A Tin filter is used to eliminate the overestimated signals in low-energy photons below 100 keV. The measurement uncertainty of the RPLGD reader system based on GD-352M should be analyzed for obtaining reliable protection quantities before using it for practical applications. Generally, the measurement uncertainty of RPLGD systems without Tin filters is analyzed for quality assurance of radiotherapy units using a high-energy photon beam. However, in this study, the measurement uncertainty of GD-352M was analyzed for evaluating the protection quantities. The measurement uncertainty factors in the RPLGD include the reference irradiation, regression curve, reproducibility, uniformity, energy dependence, and angular dependence, as described by the International Organization for Standardization (ISO). These factors were calculated using the Guide to the Expression of Uncertainty in Measurement method, applying ISO/ASTM standards 51261(2013), 51707(2015), and SS-ISO 22127(2019). The measurement uncertainties of the RPLGD reader system with a coverage factor of k = 2 were calculated to be 9.26% from 0.005 to 1 Gy and 8.16% from 1 to 10 Gy. A blind test was conducted to validate the RPLGD reader system, which demonstrated that the readout doses included blind doses of 0.1, 1, 2, and 5 Gy. Overall, the En values were considered satisfactory.
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- 2022
19. Ön Segment Optik Koherens Tomografi ile Merkezi Kornea Kalınlığı Ölçümlerinin Bireysel Bağımlılık ve Tekrarlanabilirliğinin Değerlendirilmesi
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Fatih Çelik and Pamuk Betül Ulucan
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Reproducibility ,genetic structures ,medicine.diagnostic_test ,business.industry ,Central corneal thickness,reproducibility,measurement ,Geography, Planning and Development ,Management, Monitoring, Policy and Law ,Santral korneal kalınlık,tekrarlanabilirlik,ölçüm ,eye diseases ,Optical coherence tomography ,Health Care Sciences and Services ,medicine ,sense organs ,Sağlık Bilimleri ve Hizmetleri ,business ,Biomedical engineering - Abstract
ÖzAmaç: Farklı zamanlarda yapılan kornea kalınlığı ölçümlerini karşılaştırmak ve kişilere bağımlılığını değerlendirmek.Gereç ve Yöntem: 30 sağlıklı genç erişkinin sağ gözlerinin santral korneal kalınlığı Anterior Segment Optical Coherence Tomography (AS-OCT) yöntemi ile birinci araştırmacı tarafından üç ayrı zamanda ölçüldü. Ayrıca ikinci araştırmacı tarafından dördüncü ölçümleri farklı bir zamanda yapıldı. Elde edilen değerler karşılaştırıldı.Bulgular: Yaş ortalaması 29.8 ± 9.1 idi. Ortalama SKK birinci ölçümde 561.90 ± 37.6 µ, ikinci ölçümde 562.20 ± 37.9 µ, üçüncü ölçümde 562.80 ± 37.7 µ idi. SKK’ nın 2. araştırmacı tarafından ölçümünde ise ortalama 562.20 ± 38.0 µ idi. İstatistiksel analizde farklı zamanlarda yapılan SKK değerleri arasında anlamlı fark bulunamamıştır (p, Aim: To compare corneal thickness measurements made at different times and to evaluate their dependence on individuals.Materials and Methods: The central corneal thickness of the right eyes of 30 healthy young adults was measured by the first investigator at three different times by the Anterior Segment Optical Coherence Tomography (AS-OCT) method. In addition, the fourth measurements were made by the second researcher at a different time. The obtained values were compared.Results: The mean age was 29.8 ± 9.1 years. The mean CCT was 561.90 ± 37.6 µ in the first measurement, 562.20 ± 37.9 µ in the second measurement, and 562.80 ± 37.7 µ in the third measurement. In the measurement of CCT by the second investigator, the mean was 562.20 ± 38.0 µ. In statistical analysis, no significant difference was found between CCT values performed at different times (p
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- 2022
20. 68Ga-DOTATATE PET/CT: The Optimum Standardized Uptake Value (SUV) Internal Reference
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Ahmed Ragab, Lowell Anthony, Jianrong Wu, Aman Chauhan, M. Elizabeth Oates, Aurela Clark, Xue Ding, Riham H. El Khouli, and Blaine T. Mischen
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PET-CT ,Reproducibility ,business.industry ,Confounding ,Standardized uptake value ,Neuroendocrine tumors ,medicine.disease ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,chemistry ,030220 oncology & carcinogenesis ,Lean body mass ,medicine ,DOTA ,Radiology, Nuclear Medicine and imaging ,Nuclear medicine ,business ,Rank correlation - Abstract
Rationale and Objectives Standardized Uptake Value (SUV) is an important semiquantitative measurement used in the clinical and research domains to assess radiopharmaceutical concentration in tumors versus normal organs, but is susceptible to many factors beyond the tumor biological environment. So, the aim of this study is to identify the optimum internal reference among organs with physiological uptake in 68Ga-DOTATATE PET/CT (DOTA PET/CT) scans. Materials and Methods This HIPAA-compliant, IRB-approved study with waiver of consent included retrospective imaging review of 180 consecutive patients with neuroendocrine tumors presenting for DOTA PET/CT image acquisition: Ga-68 DOTATATE dose was reported as (0.054 mCi/Kg) scans between September 2018 and May 2019. Mean value of body weight normalized SUV (SUVbw) and lean body mass normalized SUV (SUL) of liver and spleen were measured. Information about the patients and scan characteristics were collected. The paired Grambsch test was used to compare variance among the measured SUVs. Spearman's rank correlation coefficient was used to assess correlation between SUVs and potential patient- and scan-specific confounding factors. Results Variance of SUL was significantly lower than variance of SUVbw in both liver and spleen (p-value Conclusion SUL is a more reproducible, less variable, and therefore more reliable quantitative measure in DOTA PET/CT scans, compared SUVbw. Among the available organs with physiological uptake, liver SUL is the optimum internal reference given the liver's larger size and uniform SUL values resulting in lower variability and better reproducibility.
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- 2022
21. The sigmoid take-off as a landmark to distinguish rectal from sigmoid tumours on MRI
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Nino Bogveradze, Doenja M.J. Lambregts, Najim el Khababi, Raphaëla C. Dresen, Monique Maas, Miranda Kusters, Pieter J. Tanis, Regina G.H. Beets-Tan, Femke Alberts, Frans C.H. Bakers, Nino Batiashvili, Geerard L. Beets, Shira de Bie, Gerlof Bosma, Vincent C. Cappendijk, Francesca Castagnoli, Ana Daushvili, Pascal Doornebosch, Remy Geenen, Brechtje Grotenhuis, Tedo Jokharidze, Max J. Lahaye, Federica Landolfi, Marjolein Leeuwenburgh, Peter Neijenhuis, Gerald Peterson, Ernst J.A. Steller, Cornelis J. Veeken, Sofie De Vuysere, Maarten Vermaas, Roy F.A. Vliegen, Albert Wolthuis, Surgery, CCA - Imaging and biomarkers, CCA - Cancer Treatment and Quality of Life, AGEM - Amsterdam Gastroenterology Endocrinology Metabolism, School Office GROW, RS: GROW - R3 - Innovative Cancer Diagnostics & Therapy, Faculteit FHML Centraal, MUMC+: DA BV Medisch Specialisten Radiologie (9), and RS: GROW - R1 - Prevention
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Male ,Colorectal cancer ,Sigmoid cancer ,Neoadjuvant treatment ,80 and over ,Medicine ,Rectal cancer ,Sigmoid take-off ,Colectomy ,Aged, 80 and over ,Observer Variation ,Potential impact ,Proctectomy ,Carcinoma/diagnostic imaging ,Anatomic Variation ,General Medicine ,Chemoradiotherapy ,Middle Aged ,Magnetic Resonance Imaging ,CANCER ,Neoadjuvant Therapy ,medicine.anatomical_structure ,Oncology ,Female ,Radiology ,Anatomic Landmarks ,MRI ,Adult ,medicine.medical_specialty ,Rectum ,COLON ,MANAGEMENT ,Humans ,Aged ,PREOPERATIVE RADIOTHERAPY ,Reproducibility ,Rectal Neoplasms ,business.industry ,Carcinoma ,Expert consensus ,Reproducibility of Results ,Sigmoid function ,medicine.disease ,Sigmoid Neoplasms ,Rectal Neoplasms/diagnostic imaging ,Surgery ,Sigmoid Neoplasms/diagnostic imaging ,business ,CONSENSUS ,POSTOPERATIVE CHEMORADIOTHERAPY - Abstract
PURPOSE: The sigmoid take-off (STO) was recently introduced as a preferred landmark, agreed upon by expert consensus recommendation, to discern rectal from sigmoid cancer on imaging. Aim of this study was to assess the reproducibility of the STO, explore its potential treatment impact and identify its main interpretation pitfalls.METHODS: Eleven international radiologists (with varying expertise) retrospectively assessed n = 155 patients with previously clinically staged upper rectal/rectosigmoid tumours and re-classified them using the STO as completely below (rectum), straddling the STO (rectosigmoid) or completely above (sigmoid), after which scores were dichotomized as rectum (below/straddling STO) and sigmoid (above STO), being the clinically most relevant distinction. A random subset of n = 48 was assessed likewise by 6 colorectal surgeons. .RESULTS: Interobserver agreement (IOA) for the 3-category score ranged from κ0.19-0.82 (radiologists) and κ0.32-0.72 (surgeons), with highest scores for the most experienced radiologists (κ0.69-0.76). Of the 155 cases, 44 (28%) were re-classified by ≥ 80% of radiologists as sigmoid cancers; 36 of these originally received neoadjuvant treatment which in retrospect might have been omitted if the STO had been applied. Main interpretation pitfalls were related to anatomical variations, borderline cases near the STO and angulation of axial imaging planes.CONCLUSIONS: Good agreement was reached for experienced radiologists. Despite considerable variation among less-expert readers, use of the STO could have changed treatment in ±1/4 of patients in our cohort. Identified interpretation pitfalls may serve as a basis for teaching and to further optimize MR protocols.
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- 2022
22. Neuroimaging studies within Cognitive Genetics Collaborative Research Organization aiming to replicate and extend works of ENIGMA
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Kenichiro Miura, Junya Matsumoto, Masaki Fukunaga, Ryota Hashimoto, Daisuke Koshiyama, Naohiro Okada, and Kiyotaka Nemoto
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magnetic resonance imaging (MRI) ,Review Article ,050105 experimental psychology ,White matter ,03 medical and health sciences ,0302 clinical medicine ,Meta-Analysis as Topic ,Neuroimaging ,Genetics ,medicine ,Humans ,Multicenter Studies as Topic ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,Bipolar disorder ,Gray Matter ,mega‐analysis ,Review Articles ,reproducibility ,neuroimaging ,Radiological and Ultrasound Technology ,business.industry ,Mental Disorders ,05 social sciences ,Cognition ,medicine.disease ,Magnetic Resonance Imaging ,White Matter ,schizophrenia ,psychiatric disorders ,medicine.anatomical_structure ,Neurology ,meta‐analysis ,Schizophrenia ,Autism spectrum disorder ,Meta-analysis ,Major depressive disorder ,Neurology (clinical) ,Anatomy ,business ,030217 neurology & neurosurgery - Abstract
Reproducibility is one of the most important issues for generalizing the results of clinical research; however, low reproducibility in neuroimaging studies is well known. To overcome this problem, the Enhancing Neuroimaging Genetics through Meta‐Analysis (ENIGMA) consortium, an international neuroimaging consortium, established standard protocols for imaging analysis and employs either meta‐ and mega‐analyses of psychiatric disorders with large sample sizes. The Cognitive Genetics Collaborative Research Organization (COCORO) in Japan promotes neurobiological studies in psychiatry and has successfully replicated and extended works of ENIGMA especially for neuroimaging studies. For example, (a) the ENIGMA consortium showed subcortical regional volume alterations in patients with schizophrenia (n = 2,028) compared to controls (n = 2,540) across 15 cohorts using meta‐analysis. COCORO replicated the volumetric changes in patients with schizophrenia (n = 884) compared to controls (n = 1,680) using the ENIGMA imaging analysis protocol and mega‐analysis. Furthermore, a schizophrenia‐specific leftward asymmetry for the pallidum volume was demonstrated; and (b) the ENIGMA consortium identified white matter microstructural alterations in patients with schizophrenia (n = 1,963) compared to controls (n = 2,359) across 29 cohorts. Using the ENIGMA protocol, a study from COCORO showed similar results in patients with schizophrenia (n = 696) compared to controls (n = 1,506) from 12 sites using mega‐analysis. Moreover, the COCORO study found that schizophrenia, bipolar disorder (n = 211) and autism spectrum disorder (n = 126), but not major depressive disorder (n = 398), share similar white matter microstructural alterations, compared to controls. Further replication and harmonization of the ENIGMA consortium and COCORO will contribute to the generalization of their research findings., The Cognitive Genetics Collaborative Research Organization (COCORO), which is a Japanese consortium established to elucidate psychiatric disorders and brain functions, replicated the results of the ENIGMA consortium, such as subcortical volume abnormalities and white matter microstructural abnormalities in schizophrenia, using the mega‐analysis method. These replication studies strengthened the reliability and generalization of the results of the ENIGMA consortium based on common and different methods in both consortiums. Further replication and harmonization of large consortia will contribute to the generalization of their research findings.
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- 2022
23. Quantitative T2 Mapping to Discriminate Mucinous from Nonmucinous Adenocarcinoma in Rectal Cancer: Comparison with Diffusion-weighted Imaging
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Yuxi Ge, Jun-Qin Zhang, Shudong Hu, Heng Zhang, Weiqiang Dou, and Zi Wang
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Tumor Regression Grade ,Reproducibility ,Receiver operating characteristic ,Rectal Neoplasms ,business.industry ,Intraclass correlation ,Youden's J statistic ,Reproducibility of Results ,Adenocarcinoma ,Sensitivity and Specificity ,Diffusion Magnetic Resonance Imaging ,Mann–Whitney U test ,Humans ,Medicine ,Effective diffusion coefficient ,Radiology, Nuclear Medicine and imaging ,business ,Nuclear medicine ,Retrospective Studies ,Diffusion MRI - Abstract
Purpose Mucinous adenocarcinoma (MA) is associated with worse clinicopathological characteristics and a poorer prognosis than non-MA. Moreover, MA is related to worse tumor regression grade and tumor downstaging than non-MA. This study investigated whether lesions in MA and non-MA can be quantitatively assessed by T2 mapping technique and compared with the diffusion-weighted imaging (DWI). Methods High-resolution MRI, DWI, and T2 mapping were performed on 81 patients diagnosed with rectal cancer via biopsy. Afterward, T2 and apparent diffusion coefficient (ADC) values were manually measured by a senior and a junior radiologist independently. By examining surgical specimens, the patients with MA and non-MA were identified. Inter-observer reproducibility was tested, and T2 and ADC values were compared using Mann-Whitney U test. Finally, receiver operating characteristic (ROC) curves were drawn to determine the cut-off value. Results Of the 81 patients, 11 patients with MA were confirmed by pathology. The inter-observer reproducibility of T2 and ADC values showed an excellent intraclass correlation coefficient (ICC) of 0.993 and 0.913, respectively. MA had higher T2 (87.9 ± 5.11 ms) (P = 0.000) and ADC (2.03 × 10-3 mm2/s) (P = 0.000) values than non-MA (66.6 ± 6.86 ms and 1.17 × 10-3 mm2/s, respectively). The area under the ROC curves (AUC) of the T2 and ADC values were 0.999 (95% confidence interval [CI]: 0.953-1) and 0.979 (95% CI: 0.920-0.998), respectively. When the cutoff value in T2 mapping was 80 ms, the Youden index was the largest, sensitivity was 100%, and specificity was 97%. Conclusion As a stable quantitative sequence, T2 mapping of MRI is useful in differentiating MA from non-MA. Compared to ADC values, T2 values are also diagnostically effective and non-inferior to ADC values.
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- 2022
24. Do machine learning platforms provide out-of-the-box reproducibility?
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Richard Juul Isdahl, Odd Erik Gundersen, and Saeid shamsaliei
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Reproducibility ,Computer Networks and Communications ,Computer science ,business.industry ,Significant difference ,Machine learning ,computer.software_genre ,Software ,Hardware and Architecture ,Artificial intelligence ,Feature set ,business ,computer - Abstract
Science is experiencing an ongoing reproducibility crisis. In light of this crisis, our objective is to investigate whether machine learning platforms provide out-of-the-box reproducibility. Our method is twofold: First, we survey machine learning platforms for whether they provide features that simplify making experiments reproducible out-of-the-box. Second, we conduct the exact same experiment on four different machine learning platforms, and by this varying the processing unit and ancillary software only. The survey shows that no machine learning platform supports the feature set described by the proposed framework while the experiment reveals statstically significant difference in results when the exact same experiment is conducted on different machine learning platforms. The surveyed machine learning platforms do not on their own enable users to achieve the full reproducibility potential of their research. Also, the machine learning platforms with most users provide less functionality for achieving it. Furthermore, results differ when executing the same experiment on the different platforms. Wrong conclusions can be inferred at the at 95% confidence level. Hence, we conclude that machine learning platforms do not provide reproducibility out-of-the-box and that results generated from one machine learning platform alone cannot be fully trusted.
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- 2022
25. Reproducibility and diurnal variation of the directional sensitivity of the cerebral pressure-flow relationship in men and women
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Marc-Antoine Roy, Patrice Brassard, Jonathan David Smirl, Lawrence Labrecque, and Joel S. Burma
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Male ,Middle Cerebral Artery ,medicine.medical_specialty ,Mean arterial pressure ,Physiology ,Intraclass correlation ,Cerebral arteries ,Blood Pressure ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,Internal medicine ,medicine.artery ,medicine ,Humans ,Arterial Pressure ,Posterior Cerebral Artery ,Reproducibility ,business.industry ,Diurnal temperature variation ,Reproducibility of Results ,Cerebral blood flow ,Cerebrovascular Circulation ,Middle cerebral artery ,Cardiology ,Female ,business ,Sensitivity (electronics) ,Blood Flow Velocity ,030217 neurology & neurosurgery - Abstract
The cerebral pressure-flow relationship has directional sensitivity, meaning the augmentation in cerebral blood flow is attenuated when mean arterial pressure (MAP) increases vs MAP decreases. We employed repeated squat-stands (RSS) to quantify it using a novel metric. However, its within-day reproducibility and the impacts of diurnal variation and biological sex are unknown. Study aims were to evaluate this metric for: 1) within-day reproducibility and diurnal variation in middle (MCA; ∆MCAvT/∆MAPT) and posterior cerebral arteries (PCA; ∆PCAvT/∆MAPT); 2) sex differences. ∆MCAvT/∆MAPT and ∆PCAvT/∆MAPT were calculated at seven time-points (08:00-17:00) in 18 participants (8 women; 24 ± 3 yrs) using the minimum-to-maximum MCAv or PCAv and MAP for each RSS at 0.05 Hz and 0.10 Hz. Relative metric values were also calculated (%MCAvT/%MAPT, %PCAvT/%MAPT). Intraclass correlation coefficient (ICC) evaluated reproducibility, which was good (0.75-0.90) to excellent (>0.90). Time-of-day impacted ∆MCAvT/∆MAPT (0.05 Hz: p = 0.002; 0.10 Hz: p = 0.001), %MCAvT/%MAPT (0.05 Hz: p = 0.035; 0.10 Hz: p = 0.009), and ∆PCAvT/∆MAPT (0.05 Hz: p = 0.024), albeit with small/negligible effect sizes. MAP direction impacted both arteries' metric at 0.10 Hz (all p < 0.024). Sex differences in the MCA only (p = 0.003) vanished when reported in relative terms. These findings demonstrate this metric is reproducible throughout the day in the MCA and PCA and is not impacted by biological sex.
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- 2022
26. Test-retest reliability of isometric mid-thigh pull maximum strength assessment: a systematic review
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Jozo Grgic, Bela Scapec, Zeljko Pedisic, and Pavle Mikulic
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Reproducibility ,medicine.medical_specialty ,business.industry ,Coefficient of variation ,Physical Therapy, Sports Therapy and Rehabilitation ,Isometric exercise ,Repeatability ,Thigh ,Test (assessment) ,medicine.anatomical_structure ,Physiology (medical) ,Physical therapy ,Medicine ,Orthopedics and Sports Medicine ,business ,Muscle architecture ,Reliability ,Testing ,Strength ,Reliability (statistics) - Abstract
The aim of this systematic review was to explore the test-retest reliability of isometric mid-thigh pull maximum strength assessment. We searched through five databases to find studies that examined the test-retest reliability of peak force in the isometric mid-thigh pull exercise. From each included study, we extracted intra-class correlation coefficients (ICC) and/or coefficient of variation (CV). The methodological quality of the included studies was evaluated using the COSMIN checklist. A total of 16 good-to-excellent quality studies were included in the review. When considering results from all included studies, ICCs ranged from 0.73 to 0.99 (median ICC = 0.96), where 78% of ICCs were ≥ 0.90, and 98% of ICCs were ≥ 0.75. The range of reported CVs was from 0.7% to 11.1% (median CV = 4.9%), where 58% of CVs were ≤ 5%. Reliability was also good-to-excellent for both relative and absolute peak force and for both bilateral and unilateral isometric mid-thigh pull tests. The majority of studies did not find significant differences between testing sessions. It can be concluded that the isometric mid-thigh pull maximum strength assessment has good-to-excellent test-retest reliability. The isometric mid-thigh pull maximum strength assessment can be used as a reliable test in sports practice and for research purposes.
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- 2022
27. Low-Cost 3-D Hydrophone Scanning Tank with MATLAB GUI Control
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Frédéric Padilla, John Snell, Erin Wettstone, Sam Clinard, Matt Eames, and David T. Moore
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Reproducibility ,Scanner ,Materials science ,Acoustics and Ultrasonics ,Radiological and Ultrasound Technology ,Hydrophone ,business.industry ,Acoustics ,Transducers ,Ultrasound ,Biophysics ,Reproducibility of Results ,law.invention ,Planar ,Pressure measurement ,Transducer ,law ,Ultrasonics ,Radiology, Nuclear Medicine and imaging ,MATLAB ,business ,computer ,computer.programming_language - Abstract
The Focused Ultrasound Foundation has developed a low-cost, validated, open-source hydrophone scanner for the spatial characterization of ultrasound transducers. Assembly instructions and a MATLAB control graphical user interface are provided such that the device can be easily replicated for less than $1000 in roughly 40 person-hours. The low-cost scanning tank's performance was compared with data collected with a commercial automated scanning tank. Pressure measurements of a focused transducer and a planar transducer had less than a 10% difference between the two scanning systems. Two-dimensional automated scans (20 × 20 mm at 0.25-mm resolution) took the low-cost scanning tank 45 min compared with the commercial system's 30 min. A reproducibility study found that the low-cost scanner made consistent peak negative pressure measurements as reflected by the low coefficient of variation for both focused (1.88%) and planar (0.98%) transducers. The low-cost scanner described here is a viable alternative for ultrasound laboratories needing efficient, accurate characterization of ultrasound transducers.
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- 2022
28. Standardization of a flow cytometry SARS-CoV-2 serologic test
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Jonathan Richard, Renée Bazin, Carl Simard, Patrick Trépanier, and Andrés Finzi
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Coronavirus disease 2019 (COVID-19) ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Clinical Biochemistry ,Biomedical Engineering ,Bioengineering ,Spike ,Virus ,Antibodies ,Seropositivity testing ,Flow cytometry ,Serology ,medicine ,Reproducibility ,medicine.diagnostic_test ,biology ,business.industry ,SARS-CoV-2 ,Area under the curve ,Cell Biology ,Virology ,Standardization ,biology.protein ,Original Article ,Antibody ,business ,Biotechnology - Abstract
The SARS-CoV-2 virus is the causing agent of the coronavirus disease 2019 (COVID-19) pandemic which is responsible for millions of deaths worldwide. The development of the humoral response to the virus has been the subject of intensive research and development. A flow cytometry-based assay using native full-length SARS-CoV-2 Spike protein expressed in 293T cells was recently proposed as a complementary seropositivity determination assay.The aim of our study was to further develop the flow cytometry assay for potential use as a confirmatory test and to standardize its parameters and results for reliable inter-laboratory use. We have optimized the protocol, established the Receiving Operating Characteristic (ROC) curve and tested reproducibility using pre-COVID plasma samples and convalescent, SARS-CoV-2 individual plasma samples.The flow-based assay was simplified and standardized by cultivating the 293T cells in suspension and expressing results in Mean Equivalent Soluble Fluorochrome (MESF) using an internal antibody positive control. The ROC curve was determined with an area under the curve (AUC) of 0.996 and the assay specificity and sensitivity were established at 100% and 97.7% respectively. Reproducibility was good as determined on multiple cytometers, on different days, and with data acquisition as far as 72h post-staining. The optimized and standardized assay could be used as a high throughput confirmation confirmatory assay in flow cytometry laboratories involved in serological testing.
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- 2022
29. Reliability of Manually Segmenting T1ρ Magnetic Resonance Sequences of Talar Articular Cartilage
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Kyle B. Kosik, Kyeongtak Song, Phillip A. Gribble, and Erik A. Wikstrom
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Cartilage, Articular ,Magnetic Resonance Spectroscopy ,Intraclass correlation ,Biophysics ,Physical Therapy, Sports Therapy and Rehabilitation ,Context (language use) ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,Orthopedics and Sports Medicine ,Segmentation ,Reliability (statistics) ,030203 arthritis & rheumatology ,Reproducibility ,medicine.diagnostic_test ,business.industry ,Rehabilitation ,Reproducibility of Results ,Magnetic resonance imaging ,030229 sport sciences ,Magnetic Resonance Imaging ,Confidence interval ,medicine.anatomical_structure ,Ankle ,Nuclear medicine ,business ,Ankle Joint - Abstract
Context: Quantifying early posttraumatic ankle osteoarthritis pathogenesis using compositional magnetic resonance (MR) imaging sequences is becoming more common. These MR sequences are often manually segmented to isolate the cartilage of interest before cartilage compositional values (eg, T1ρ or T2) are quantified. However, limited information is available regarding the reliability and reproducibility of manual segmentation for the entire talar dome. Objective: The purpose of this study was to determine the intraobserver and interobserver reliability of manually segmenting T1ρ MR sequences of the entire talar dome and 4 subregions of interest. Design: Descriptive observational study. Setting: Laboratory. Patients or Other Participants: Ten uninjured healthy individuals (4M and 6F: 21.40 [3.03] y, 170.00 [7.93] cm, 71.03 [14.97] kg) participated. Intervention: None. Main Outcome Measures: Two investigators manually segmented 10 T1ρ ankle MR sequences using ITK-SNAP software to calculate T1ρ mean relaxation times and cartilage volumes. Each observer repeated the segmentation twice, with segmentations separated by 1 month. Intraobserver and interobserver reliability was determined using intraclass correlation coefficients (ICCs) with 95% confidence intervals and root mean square coefficient of variations (RMSCVs). Results: For T1ρ relaxation time, intraobserver (ICC = .994–.997, RMSCV = 1.31%–1.51%) and interobserver reliability (ICC = .990, RMSCV = 2.36%) was excellent for the overall talar dome. Excellent intraobserver (ICC = .975–.980, RMSCV = 3.88%–4.59%) and excellent interobserver reliability (ICC = .970, RMSCV = 5.13%) was noted for overall talar cartilage volume. Conclusions: The results demonstrate that manual segmentation of the entire talar dome from a T1ρ MR is reliable and repeatable.
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- 2022
30. Digital validation of breast biomarkers (ER, PR, AR, and HER2) in cytology specimens using three different scanners
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Marcia Edelweiss, Abeer M. Salama, Oscar Lin, Marc-Henri Jean, Matthew G. Hanna, Edi Brogi, Christina E Vallejo, Dilip Giri, and Brie Kezlarian
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Pathology ,medicine.medical_specialty ,Pathology, Surgical ,Receptor, ErbB-2 ,Concordance ,H&E stain ,Breast Neoplasms ,Pathology and Forensic Medicine ,Cohort Studies ,Random Allocation ,Breast cancer ,Cytology ,Biomarkers, Tumor ,Humans ,Medicine ,Reproducibility ,business.industry ,Digital pathology ,Prognosis ,medicine.disease ,Immunohistochemistry ,Receptors, Estrogen ,Receptors, Androgen ,Female ,Receptors, Progesterone ,business ,Nuclear medicine ,Kappa - Abstract
Progression in digital pathology has yielded new opportunities for a remote work environment. We evaluated the utility of digital review of breast cancer immunohistochemical prognostic markers (IHC) using whole slide images (WSI) from formalin fixed paraffin embedded (FFPE) cytology cell block specimens (CB) using three different scanners.CB from 20 patients with breast cancer diagnosis and available IHC were included. Glass slides including 20 Hematoxylin and eosin (H&E), 20 Estrogen Receptor (ER), 20 Progesterone Receptor (PR), 16 Androgen Receptor (AR), and 20 Human Epidermal Growth Factor Receptor 2 (HER2) were scanned on 3 different scanners. Four breast pathologists reviewed the WSI and recorded their semi-quantitative scoring for each marker. Kappa concordance was defined as complete agreement between glass/digital pairs. Discordances between microscopic and digital reads were classified as a major when a clinically relevant change was seen. Minor discordances were defined as differences in scoring percentages/staining pattern that would not have resulted in a clinical implication. Scanner precision was tabulated according to the success rate of each scan on all three scanners.In total, we had 228 paired glass/digital IHC reads on all 3 scanners. There was strong concordance kappa ≥0.85 for all pathologists when comparing paired microscopic/digital reads. Strong concordance (kappa ≥0.86) was also seen when comparing reads between scanners.Twenty-three percent of the WSI required rescanning due to barcode detection failures, 14% due to tissue detection failures, and 2% due to focus issues. Scanner 1 had the best average precision of 92%. HER2 IHC had the lowest intra-scanner precision (64%) among all stains.This study is the first to address the utility of WSI in breast cancer IHC in CB and to validate its reporting using 3 different scanners. Digital images are reliable for breast IHC assessment in CB and offer similar reproducibility to microscope reads.
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- 2022
31. Vascular Deformation Mapping for CT Surveillance of Thoracic Aortic Aneurysm Growth
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Jianyang Zhong, Gary E. Christensen, Nicholas S. Burris, Zhangxing Bian, Theodorus M. J. van Bakel, Brian D. Ross, Charles R. Hatt, Jeffrey Dominic, Himanshu J. Patel, and Ignas B Houben
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Male ,Computed Tomography Angiography ,Aorta, Thoracic ,Thoracic aortic aneurysm ,Imaging, Three-Dimensional ,Dilated segment ,Interquartile range ,medicine.artery ,Ascending aorta ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,Retrospective Studies ,Reproducibility ,medicine.diagnostic_test ,Aortic Aneurysm, Thoracic ,business.industry ,Reproducibility of Results ,medicine.disease ,Descending aorta ,Angiography ,Area ratio ,Female ,Nuclear medicine ,business - Abstract
Background Aortic diameter measurements in patients with a thoracic aortic aneurysm (TAA) show wide variation. There is no technique to quantify aortic growth in a three-dimensional (3D) manner. Purpose To validate a CT-based technique for quantification of 3D growth based on deformable registration in patients with TAA. Materials and Methods Patients with ascending and descending TAA with two or more CT angiography studies between 2006 and 2020 were retrospectively identified. The 3D aortic growth was quantified using vascular deformation mapping (VDM), a technique that uses deformable registration to warp a mesh constructed from baseline aortic anatomy. Growth assessments between VDM and clinical CT diameter measurements were compared. Aortic growth was quantified as the ratio of change in surface area at each mesh element (area ratio). Manual segmentations were performed by independent raters to assess interrater reproducibility. Registration error was assessed using manually placed landmarks. Agreement between VDM and clinical diameter measurements was assessed using Pearson correlation and Cohen κ coefficients. Results A total of 38 patients (68 surveillance intervals) were evaluated (mean age, 69 years ± 9 [standard deviation]; 21 women), with TAA involving the ascending aorta (n = 26), descending aorta (n = 10), or both (n = 2). VDM was technically successful in 35 of 38 (92%) patients and 58 of 68 intervals (85%). Median registration error was 0.77 mm (interquartile range, 0.54-1.10 mm). Interrater agreement was high for aortic segmentation (Dice similarity coefficient = 0.97 ± 0.02) and VDM-derived area ratio (bias = 0.0, limits of agreement: -0.03 to 0.03). There was strong agreement (r = 0.85, P < .001) between peak area ratio values and diameter change. VDM detected growth in 14 of 58 (24%) intervals. VDM revealed growth outside the maximally dilated segment in six of 14 (36%) growth intervals, none of which were detected with diameter measurements. Conclusion Vascular deformation mapping provided reliable and comprehensive quantitative assessment of three-dimensional aortic growth and growth patterns in patients with thoracic aortic aneurysms undergoing CT surveillance. Published under a CC BY 4.0 license Online supplemental material is available for this article. See also the editorial by Wieben in this issue.
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- 2023
32. Research material sharing in accounting research
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Gassen, Joachim, Klug, Jacqueline, and Van Pelt, Victor
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Data Sharing ,Open Science ,Economics ,Accounting ,Business ,Social and Behavioral Sciences ,Reproducibility - Abstract
We will contact 2,490 authors of papers published in the six top accounting journals from 2016-2021: Journal of Accounting and Economics, Journal of Accounting Research, The Accounting Review, Contemporary Accounting Research, Accounting, Organizations and Society, and Review of Accounting Studies. We obtained their contact information online. We will ask them to read a short scenario and imagine that they are a researcher whom a fellow researcher is approaching with a request to share research materials. We will manipulate whether the act of sharing is control-focused versus collaboration-focused and private versus public. We will then ask participants to state how likely they would comply with the request of their fellow researcher if they were the person described in the scenario. After answering this question, which is our primary dependent variable of interest, participants reflect on their answer, and complete a short survey containing demographic questions and a few questions adapted from the State of Social Science Survey.
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- 2023
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33. Development, validity and reproducibility of a dish-based semi-quantitative food frequency questionnaire in Iran
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Zahra Yaghoubi, Habibollah Esmaily, Sara Movahed, Mohammad Reza Shadmand Foumani Moghadam, Seyed Amir Reza Mohajeri, Samaneh Sadat Ayoubi, Karim Karbin, Abdolreza Norouzy, Hamidreza Bahrami Taghanaki, Mohsen Nematy, and Maryam Amini
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Reproducibility ,medicine.medical_specialty ,Nutrition and Dietetics ,business.industry ,Endocrinology, Diabetes and Metabolism ,medicine ,food and beverages ,Food frequency questionnaire ,Medical physics ,business ,Semi quantitative ,Food Science - Abstract
BACKGROUND: The food frequency questionnaire (FFQ) is the method of choice for dietary assessment in epidemiological studies. FFQs focusing on mixed-dishes and simple food items are useful where mixed-dishes are an essential part of food consumption. OBJECTIVE: Regarding the fact that the nature of the Iranian diet is mixed-dish, the present study aimed to design and assess the validity and reproducibility of a dish-based semi-quantitative FFQ in the Iranian adult population. METHODS: A list of 302 food items was collected from four geographical areas around Iran. The validation study was conducted on 97 healthy adults. The FFQ was introduced at the beginning of the study and 10 months after; two three-day food records were collected during the study. Also, biomarkers including 24-hour urinary potassium and nitrogen, serum retinol, and alpha-tocopherol were measured. RESULTS: A 142-food-item FFQ was concluded. The correlation coefficient between the second FFQ and the second three-day food record ranged from 0.225 to 0.323 for macronutrients and 0.128 to 0.476 for micronutrients. The percentile agreements (same or adjacent quartile) between the two methods were more than 60% for all nutrients. The intraclass correlation coefficient between FFQs (except for vitamin E) ranged from 0.363 to 0.578. The correlation coefficient between the second FFQ and the second biomarker assessment was 0.241 for protein.
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- 2021
34. Statistical reproducibility for pairwise t-tests in pharmaceutical research
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Andrea Simkus, Tahani Coolen-Maturi, Frank P. A. Coolen, Claus Bendtsen, and Natasha A. Karp
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Statistics and Probability ,Reproducibility ,Wilcoxon signed-rank test ,Epidemiology ,business.industry ,Computer science ,Nonparametric statistics ,Inference ,Machine learning ,computer.software_genre ,Predictive inference ,Health Information Management ,Mann–Whitney U test ,Pairwise comparison ,Artificial intelligence ,business ,computer ,Statistical hypothesis testing - Abstract
This paper investigates statistical reproducibility of the [Formula: see text]-test. We formulate reproducibility as a predictive inference problem and apply the nonparametric predictive inference method. Within our research framework, statistical reproducibility provides inference on the probability that the same test outcome would be reached, if the test were repeated under identical conditions. We present an nonparametric predictive inference algorithm to calculate the reproducibility of the [Formula: see text]-test and then use simulations to explore the reproducibility both under the null and alternative hypotheses. We then apply nonparametric predictive inference reproducibility to a real-life scenario of a preclinical experiment, which involves multiple pairwise comparisons of test groups, where different groups are given a different concentration of a drug. The aim of the experiment is to decide the concentration of the drug which is most effective. In both simulations and the application scenario, we study the relationship between reproducibility and two test statistics, the Cohen’s [Formula: see text] and the [Formula: see text]-value. We also compare the reproducibility of the [Formula: see text]-test with the reproducibility of the Wilcoxon Mann–Whitney test. Finally, we examine reproducibility for the final decision of choosing a particular dose in the multiple pairwise comparisons scenario. This paper presents advances on the topic of test reproducibility with relevance for tests used in pharmaceutical research.
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- 2021
35. Evaluation of neonatal cerebral perfusion using three‐dimensional power Doppler ultrasound volumes
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Tim Schindler, Gerrie Beirne, Alec W. Welsh, Sonali Jayatilake, Abidev Kuhasri, and Gordon N. Stevenson
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Neonatal intensive care unit ,Population ,Blood volume ,Imaging, Three-Dimensional ,Region of interest ,Animals ,Humans ,Medicine ,3D ultrasound ,Cerebral perfusion pressure ,education ,Observer Variation ,Reproducibility ,education.field_of_study ,medicine.diagnostic_test ,business.industry ,Infant, Newborn ,Reproducibility of Results ,Ultrasonography, Doppler ,General Medicine ,Perfusion ,Cerebrovascular Circulation ,Pediatrics, Perinatology and Child Health ,Female ,business ,Nuclear medicine ,Infant, Premature - Abstract
AIM Despite improvement in preterm survival, neurological morbidity remains high. 3D fractional moving blood volume (3D-FMBV) quantifies neonatal cerebral perfusion by calculating a standardised measure of the amount of moving blood in a region of interest and correlates with tissue perfusion in animal studies. However, its feasibility and reproducibility are yet to be assessed in newborn infants. METHODS Fractional moving blood volume analysis was performed on three-dimensional power Doppler ultrasound (PD-US) volumes from a cohort of preterm infants recruited in 2015 from the Royal Hospital for Women Neonatal Intensive Care Unit. The volumes were acquired by two sonographers and analysed by two different observers. The 3D-FMBV algorithm was applied to calculate an estimate for perfusion. Reproducibility and agreement were assessed using intra-class correlation coefficients (ICC) and Bland-Altman plots. RESULTS All 3D PD-US volumes were analysed successfully. Intra-observer reliability was excellent with an ICC of 0.907 (95% CI 0.751-0.968) and 0.906 (95% CI 0.741-0.967) for two independent observers respectively. The inter-observer reliability of the entire technique was good with an ICC of 0.752 (CI: 0.404-0.909). CONCLUSION We have successfully shown the feasibility and reliability of applying the 3D-FMBV technique to the neonatal brain in a healthy preterm population.
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- 2021
36. Reliability of performing ultrasound derived SWE and fat fraction in adult livers
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Candance Wong, David Park, Jing Gao, and Megan Maar
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Adult ,Liver Cirrhosis ,Male ,Reproducibility ,business.industry ,Intraclass correlation ,Wave velocity ,Ultrasound ,Reproducibility of Results ,Repeatability ,Middle Aged ,Confidence interval ,Liver ,Elasticity Imaging Techniques ,Humans ,Medicine ,Female ,Radiology, Nuclear Medicine and imaging ,business ,Nuclear medicine ,Reliability (statistics) ,Ultrasonography ,Fat fraction - Abstract
Purpose The aim of the study was to test the reproducibility of performing conventional point shear wave elastography (pSWE), auto-pSWE, and ultrasound derived fat fraction (UDFF) in adult livers. Methods The Institutional Review Board approved the study and all participants provided written informed consent. Conventional pSWE (obtaining 10 measurements through 10 acquisitions), auto-pSWE (automatically obtaining 15 measurements by a single acquisition), and UDFF (one measurement obtained by one acquisition) of the liver were prospectively performed in 21 participants (10 men, 11 women, mean age 63y) by senior and junior operators in February-May 2021. Shear wave velocity (SWV, m/s) of the liver was measured by conventional pSWE and auto-pSWE. Intraclass correlation coefficient (ICC) and Bland-Altman limits of agreement were used to test intra-observer repeatability and inter-observer reproducibility in measuring pSWE, auto-pSWE, and UDFF. Results ICC for testing intra-observer repeatability and inter-observer reproducibility in performing pSWE, auto-pSWE, and UDFF was >0.85 (95% confidence interval 0.85-0.99). The mean difference of 95% Bland-Altman limits of agreement was -0.02 (upper 0.09, lower -0.12) and the correlation of SWV measured between conventional pSWE and auto-pSWE methods was strong (r2 = 0.87). Conclusion Our results suggest good repeatability and reproducibility in measuring UDFF and SWV in adult livers. The auto-pSWE has higher reliability, reproducibility and time efficacy in measuring SWV of adult livers when compared to conventional pSWE method.
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- 2021
37. Thermoelectric Ag2Se: Imperfection, Homogeneity, and Reproducibility
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Shao-Ji Huang, Heyang Chen, Xun Shi, Kunpeng Zhao, Tian-Ran Wei, Jie Xiao, and Min Zhu
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Work (thermodynamics) ,Reproducibility ,Electron mobility ,Materials science ,Semiconductor ,business.industry ,Homogeneity (statistics) ,Thermoelectric effect ,Spark plasma sintering ,General Materials Science ,Thermal stability ,Composite material ,business - Abstract
Ag2Se is a narrow band gap n-type semiconductor with high carrier mobility and low lattice thermal conductivity. It has high thermoelectric performance near room temperature. However, there is a noticeable data discrepancy for thermoelectric performance in the reported literature studies, which greatly hinders the rational understanding and potential application of this material. In this work, we comprehensively studied the homogeneity, reproducibility, and thermal stability of bulk Ag2Se prepared by melting and mechanical alloying methods followed by spark plasma sintering. By virtue of the atom probe topology technique, we revealed nanosized Ag- or Se-rich precipitates and micropores with Se-aggregated interfaces that have not been detected previously. The samples prepared by melting and spark plasma sintering exhibit the best homogeneity and repeatability in thermoelectric properties despite abundant nanoprecipitates. Moreover, the thermoelectric performance of Ag2Se is greatly improved by introducing a slight amount of excess selenium. The average zT can steadily reach 0.8-0.9 in the range of 300-380 K, which is among the highest values reported for Ag2Se-based materials. This work will rationalize the evaluation of the thermoelectric performance of Ag2Se.
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- 2021
38. Interassay and interobserver comparability study of four programmed death-ligand 1 (PD-L1) immunohistochemistry assays in triple-negative breast cancer
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Alexander Hapfelmeier, Sebastian Foersch, Siranush Karapetyan, Daniel-Christoph Wagner, Katja Steiger, Kristina Schwamborn, Marion Kiechle, Wilko Weichert, Wilfried Roth, Dirk Oettler, and Aurelia Noske
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Oncology ,CPS, combined positive score ,TC, tumor cells ,ICI, immune checkpoint inhibitor ,Triple Negative Breast Neoplasms ,B7-H1 Antigen ,Medicine ,HER2, human epidermal growth factor receptor 2 ,Triple-negative breast cancer ,RC254-282 ,ICC, intraclass correlation coefficient ,biology ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,General Medicine ,MSI, microsatellite instability ,Immunohistochemistry ,pCR, pathological complete response ,PFS, progression-free survival ,Original Article ,IC-Score ,IC, immune cells ,IHC, immunohistochemistry ,Programmed death ,PD-L1 ,medicine.medical_specialty ,Concordance ,TNBC, triple-negative breast cancer ,OS, overall survival ,Breast cancer ,Internal medicine ,TPS, tumor proportion score ,Biomarkers, Tumor ,Humans ,Programmed death-ligand 1 ,Reproducibility ,business.industry ,Reproducibility of Results ,medicine.disease ,ITT, intention to treat ,CI, confidence interval ,PD-L1, programmed death-ligand 1 ,biology.protein ,Surgery ,CPS ,business ,Kappa ,TMB, tumor mutational burden - Abstract
Different immunohistochemical programmed death-ligand 1 (PD-L1) assays and scorings have been reported to yield variable results in triple-negative breast cancer (TNBC). We compared the analytical concordance and reproducibility of four clinically relevant PD-L1 assays assessing immune cell (IC) score, tumor proportion score (TPS), and combined positive score (CPS) in TNBC. Primary TNBC resection specimens (n = 104) were stained for PD-L1 using VENTANA SP142, VENTANA SP263, DAKO 22C3, and DAKO 28–8. PD-L1 expression was scored according to guidelines on virtual whole slide images by four trained readers. The mean PD-L1 positivity at IC-score ≥1% and CPS ≥1 ranged between 53% and 75% with the highest positivity for SP263 and comparable levels for 22C3, 28–8, and SP142. Inter-assay agreement was good between 28–8 and 22C3 across all scores and cut-offs (kappa 0.68–0.74) and for both assays with SP142 at IC-score ≥1% and CPS ≥1 (kappa 0.61–0.67). The agreement between SP263 and all other assays was substantially lower for all scores. Inter-reader agreement for each assay was good to excellent for IC-score ≥1% (kappa 0.73–0.78) and CPS ≥1 (kappa 0.68–0.74), fair to good for CPS ≥10 (kappa 0.52–0.67) and TPS ≥1% (kappa 0.53–0.72). The percentage of overlapping cases in the positive/negative category was >90% between IC-score ≥1% and CPS ≥1 but below when comparing IC-score ≥1% with CPS ≥10. We demonstrate an overall good inter-reader agreement for all PD-L1 assays in TNBC along with assay specific differences in positivity and concordances, which may aid to select the right test strategy in routine diagnostics., Highlights • Different PD-L1 IHC assays and scorings may show variable results in TNBC. • Overall good assay concordance between SP142, 22C3, and 28–8 at IC-score 1%. • Overall good assay concordance between SP142, 22C3, and 28–8 at CPS 1. • SP142 is less optimal for CPS assessment at higher cut-offs. • SP263 assay is not interchangeable with the other three PD-L1 assays.
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- 2021
39. Validation of the AO Spine Sacral Classification System: Reliability Among Surgeons Worldwide
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Emiliano Neves Vialle, F. Cumhur Oner, Mark F. Kurd, Marcel Dvorak, Alexander R. Vaccaro, Conor P. Kleweno, Frank Kandziora, Klaus J. Schnake, Michael G. Fehlings, Brian A. Karamian, Jefferson R. Wilson, Jens R. Chapman, Luiz Roberto Vialle, Rajasekaran Shanmuganathan, James C. Krieg, Jose A. Canseco, Rishi Mugesh Kanna, Gregory D. Schroeder, Reza Firoozabadi, Lorin Michael Benneker, Andrei Fernandes Joaquim, Jörg H. Holstein, and Christopher K. Kepler
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Sacrum ,sacral fracture ,medicine.medical_specialty ,Outcome measurements ,AO Spine Classification ,pelvis fracture ,Fractures, Bone ,Cohen's kappa ,spine trauma ,Humans ,Medicine ,Orthopedics and Sports Medicine ,Reliability (statistics) ,Observer Variation ,Surgeons ,Reproducibility ,reliability ,Kappa value ,business.industry ,interobserver ,Reproducibility of Results ,Level iv ,General Medicine ,Evidence-based medicine ,international ,ComputingMethodologies_DOCUMENTANDTEXTPROCESSING ,Physical therapy ,Original Article ,Surgery ,business ,Kappa - Abstract
Supplemental Digital Content is Available in the Text., Objectives: To (1) demonstrate that the AO Spine Sacral Classification System can be reliably applied by general orthopaedic surgeons and subspecialists universally around the world and (2) delineate those injury subtypes that are most difficult to classify reliably to refine the classification before evaluating clinical outcomes. Design: Agreement study. Setting: All-level trauma centers, worldwide. Participants: One hundred seventy-two members of the AO Trauma and AO Spine community. Intervention: The AO Sacral Classification System was applied by each surgeon to 26 cases in 2 independent assessments performed 3 weeks apart. Main Outcome Measurements: Interobserver reliability and intraobserver reproducibility. Results: A total of 8097 case assessments were performed. The kappa coefficient for interobserver agreement for all cases was 0.72/0.75 (assessment 1/assessment 2), representing substantial reliability. When comparing classification grading (A/B/C) regardless of subtype, the kappa coefficient was 0.84/0.85, corresponding to excellent reliability. The kappa coefficients for interobserver reliability were 0.95/0.93 for type A fractures, 0.78/0.79 for type B fractures, and 0.80/0.83 for type C fractures. The overall kappa statistic for intraobserver reliability was 0.82 (range 0.18–1.00), representing excellent reproducibility. When only evaluating morphology type (A/B/C), the average kappa value was 0.87 (range 0.18–1.00), representing excellent reproducibility. Conclusion: The AO Spine Sacral Classification System is universally reliable among general orthopaedic surgeons and subspecialists worldwide, with substantial interobserver and excellent intraobserver reliability.
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- 2021
40. Reliability and Validity of Abdominal Skeletal Muscle Area Measurement Using Magnetic Resonance Imaging
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Ling-Ling Sun, He Sun, Shinong Pan, Feng-Zhe Wang, and Jun Zhou
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Observer Variation ,Sarcopenia ,Reproducibility ,medicine.diagnostic_test ,Correlation coefficient ,Intraclass correlation ,business.industry ,Coefficient of variation ,Reproducibility of Results ,Magnetic resonance imaging ,SMA ,Magnetic Resonance Imaging ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Lumbar ,030220 oncology & carcinogenesis ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Bland–Altman plot ,Muscle, Skeletal ,Tomography, X-Ray Computed ,Nuclear medicine ,business - Abstract
RATIONALE AND OBJECTIVES Skeletal muscle mass measurement is the most important element for diagnosing sarcopenia. MRI has an excellent soft-tissue contrast, which can non-invasively assess abdominal skeletal muscle area (SMA) as well as CT. This study aimed to assess the validity and reliability of abdominal SMA measurement by comparing CT and MRI based on the fat image of IDEAL-IQ sequence at the lumbar level mid-L3. MATERIALS AND METHODS CT and MRI images of 32 patients diagnosed with various kidney diseases were used to analyze intra-observer variability among abdominal SMA measurements. This was done to evaluate the correlation of SMA between CT and fat images of MRI. SMA images were segmented using Materialise Mimics software before quantification. Interobserver reliability and validation of measurements was evaluated by two independent investigators. Abdominal SMA reproducibility and correlation between CT and MRI were then assessed using the intraclass correlation coefficient (ICC), coefficient of variation (CV), Bland-Altman plot, and Pearson's correlation coefficient respectively. RESULTS The interobserver reliability of MRI was excellent. The CV value was 2.82% while the ICC values ranged between 0.996 and 0.999. Validity was high (CV was 1.7% and ICC ranged between 0.986 and 0.996) for measurements by MRI and CT. Bland Altman analysis revealed an average difference of 2.2% between MRI and CT. The Pearson's correlation coefficient was 0.995 (p < 0.0001). This result revealed that there was a strong correlation between the two technologies. CONCLUSION MRI exhibited good interobserver reliability and excellent agreement with CT for quantification of abdominal SMA.
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- 2021
41. Usefulness of quantitative bone SPECT/CT for medication-related osteonecrosis of the jaw in clinical settings
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Kuniyasu Moridera, Kyohei Yoshikawa, Hiromitsu Kishimoto, Kazuhiro Kitajima, Koichiro Yamakado, Kazuma Noguchi, Kazuki Takaoka, and Tatsuya Tsuchitani
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Reproducibility ,Single Photon Emission Computed Tomography Computed Tomography ,business.industry ,Oral surgery ,Intraclass correlation ,Osteonecrosis ,Reproducibility of Results ,Clinical settings ,medicine.disease ,Bone and Bones ,Post-hoc analysis ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Stage (cooking) ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,Osteonecrosis of the jaw ,Bone volume - Abstract
Objective This study was conducted to investigate the clinical utility of quantitative bone single-photon computed tomography-computed tomography (SPECT/CT) for detection and classification for medication-related osteonecrosis of the jaw (MRONJ). Materials and methods Fifty-nine patients (69 lesions) clinically diagnosed as MRONJ by four specialists of Japanese Society of Oral Surgery according to the AAOMS diagnostic criteria and who underwent bone SPECT/CT were enrolled. One reader determined standard uptake values (SUVs), including maximum (SUVmax), peak (SUVpeak), and mean (SUVmean), as well as metabolic bone volume (MBV), representing total volume above threshold, and total bone uptake (TBU), calculated as MBV × SUVmean, using the GI-BONE software package. One-way repeated-measures analysis of variance and subsequent post hoc analysis were employed to compare quantitative values between clinical stages. To check reproducibility of values, another reader calculated these quantitative values. Results Mean SUVmax values for stage 0 (n = 21), 1 (n = 13), 2 (n = 25), and 3 (n = 10) were 5.82 ± 3.20, 5.46 ± 3.79, 8.16 ± 3.93, and 10.57 ± 8.43, respectively, while values for MBV were 9.52 ± 6.33, 11.36 ± 7.32, 12.4 ± 8.21, and 17.84 ± 16.94, respectively, and for TBU were 40.60 ± 46.97, 53.70 ± 77.26, 62.37 ± 42.91, and 102.01 ± 74.52, respectively. There were significant differences for SUVmax, SUVpeak, and SUVmean between clinical stages (p = 0.024, p = 0.027, p = 0.039, respectively). Subsequent post hoc analysis showed that SUVmax and SUVpeak of stage 3 were significantly higher than those of stage 0 (p = 0.046, 0.045, respectively). MBV and TBU showed a tendency to increase with increased stage, though differences between stages were not significant (p = 0.15, p = 0.053, respectively). Little differences of mean SUVmax, SUVpeak, SUVmean, MBV, and TBU between two readers were observed (- 3.10%, - 0.26%, - 4.24%%, 0.69%, and - 3.42%, respectively). The intraclass correlation coefficients (ICCs) of SUVmax, SUVpeak, SUVmean, MBV, and TBU were 0.985, 0.990, 0.980, 0.994, and 0.994, respectively (almost perfect for all values). Conclusion As objective and reliable indicators, SUVmax and SUVpeak derived from quantitative bone SPECT/CT results are useful for detection of early status disease, as well as staging in MRONJ patients.
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- 2021
42. Right ventricular free wall contractility in subcostal views: A proof‐of‐concept study to assess right ventricular systolic function
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Srikanth Vallurupalli and Angel López-Candales
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medicine.medical_specialty ,Reproducibility ,Systole ,business.industry ,Area under the curve ,Curve analysis ,Reproducibility of Results ,Heart ,Systolic function ,Doppler imaging ,Contractility ,Internal medicine ,Ventricular Function, Right ,medicine ,Cardiology ,Humans ,Radiology, Nuclear Medicine and imaging ,In patient ,Right Ventricular Free Wall ,Cardiology and Cardiovascular Medicine ,business - Abstract
BACKGROUND Normal right ventricular (RV) function has been traditionally assessed from the apical window. However, in several patients the subcostal window is the only available acoustic. METHODS Given the intricate functional and mechanical inter-dependence between longitudinal tricuspid annular (TA) displacement and RV free wall contractility (RVFW), we studied the utility of RVFW inward motion using both M-mode and velocity with tissue Doppler imaging (TDI) from the subcostal transthoracic view. RESULTS If a TAPSE value ≥ 2 cm is used to identify normal RV function, an RVFW M-mode value > .8 cm, TA TDI s' velocity > .06 cm/s and TA TDI e' velocity value > .05 cm/s identify normal RV systolic function. Furthermore, ROC curve analysis for the RVFW M-mode showed an area under the curve (AUC) of .753 (95% CI: .604-.868) with a cut-off value > .8, sensitivity 75% and specificity 73%; for TA TDI s' AUC at .822 (95% CI: .681-.919) with a cut-off value > .06, sensitivity 75% and specificity 77% and for TA TDI e' the AUC was .771 (95% CI: .624-.882) with a cut-off value > .05, sensitivity 90% and specificity 46%. Reproducibility of repeat RVFW M-mode, TDI s' and e' measurements was good with strong inter-rater agreement (Kappa > .8). CONCLUSIONS The subcostal window appears useful for assessing RV systolic function. Additional studies are now required to prospectively use these measures in the routine evaluation of RV systolic function particularly in patients with suboptimal apical windows.
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- 2021
43. Lung Ultrasound for Pleural Line Abnormalities, Confluent <scp>B‐Lines,</scp> and Consolidation
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Taro Minami, Kosuke Yasukawa, Ernest A Fischer, and Irene W. Y. Ma
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Observer Variation ,Independent Rater ,Reproducibility ,Radiological and Ultrasound Technology ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Intraclass correlation ,COVID-19 ,Reproducibility of Results ,Reference Standards ,Confidence interval ,Lung ultrasound ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,business ,Nuclear medicine ,Lung ,Pleural line ,Kappa ,Ultrasonography - Abstract
OBJECTIVES: Discrete B-lines have clear definitions, but confluent B-lines, consolidations, and pleural line abnormalities are less well defined. We proposed definitions for these and determined their reproducibility using COVID-19 patient images obtained with phased array probes. METHODS: Two raters collaborated to refine definitions, analyzing disagreements on 107 derivation scans from 10 patients. Refined definitions were used by those raters and an independent rater on 1260 validation scans from 105 patients. Reliability was evaluated using intraclass correlation coefficients (ICC) or Cohen's kappa. RESULTS: The agreement was excellent between collaborating raters for B-line abnormalities, ICC = 0.97 (95% confidence interval [CI] 0.97-0.98) and pleural line to consolidation abnormalities, ICC = 0.90 (95% CI 0.87-0.92). The independent rater's agreement for B-line abnormalities was excellent, ICC = 0.97 (95% CI 0.96-0.97) and for pleural line to consolidation was good, ICC = 0.88 (95% CI 0.84-0.91). Agreement just on pleural line abnormalities was weak (collaborators, kappa = 0.54, 95% CI 0.48-0.60;independent, kappa = 0.54, 95% CI 0.49-0.59). CONCLUSION: With proposed definitions or via collaboration, overall agreement on confluent B-lines and pleural line to consolidation abnormalities was robust. Pleural line abnormality agreement itself was persistently weak and caution should be used interpreting pleural line abnormalities with only a phased array probe.
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- 2021
44. Rhinogoniometer: Validation of an Instrument for Rhinoplasty
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Therency Kamila dos Santos, Lydia Masako Ferreira, and Eduardo Nascimento Silva
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Orthodontics ,Reproducibility ,Anthropometry ,business.industry ,medicine.medical_treatment ,Computerized analysis ,Significant difference ,Reproducibility of Results ,Rhinoplasty ,Nasal valve ,Cross-Sectional Studies ,Treatment Outcome ,Double-Blind Method ,Nasal Cartilages ,medicine ,Humans ,Surgery ,business ,Software - Abstract
SUMMARY The position of the lower lateral cartilages is directly related to good nasal functionality. When these cartilages exhibit cephalic malposition, the angle of divergence between cartilages is usually less than 60 degrees, which can cause external nasal valve insufficiency. The objective of this study was to validate the rhinogoniometer, an innovative surgical instrument that allows for diagnosing the position of this cartilage intraoperatively. In the intraoperative period, the angle of divergence, which is the angle formed between the two lateral branches of the lower lateral cartilages, was measured in 31 primary rhinoplasty patients. The rhinogoniometer measurement was compared with that of the computerized analysis, and the reproducibility of measurements with the rhinogoniometer between two different surgeons was determined. When comparing the values obtained by the two methods, a significant difference was found (p = 0.034). On average, the angles measured by the rhinogoniometer were 3.7 degrees smaller than the measurements made by the software. It was observed that when the angles measured by both methods were above 75 degrees, the differences between the two measurements were higher (p = 0.022). However, for angles up to 75 degrees, the measurement using the rhinogoniometer was, on average, 0.79 degrees higher than the measurement taken by the software. When the difference in angles obtained by the two methods between different surgeons was evaluated, there was a significant difference (p < 0.023). In conclusion, at angles up to 75 degrees, the rhinogoniometer showed a negligible difference of 0.79 degrees higher than the measurement obtained via software. Measurements with the rhinogoniometer were also shown to be reproducible with different surgeons.
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- 2021
45. A prospective study on inter-operator variability in semi-robotic software-based MRI/TRUS-fusion targeted prostate biopsies
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Fabian Tollens, Manuel Neuberger, Manuel Ritter, Jost von Hardenberg, Niklas Westhoff, Samuel Doryumu, Fabian Derigs, Dominik Nörenberg, and Maurice Stephan Michel
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Image-Guided Biopsy ,Male ,Nephrology ,medicine.medical_specialty ,Prostate biopsy ,Urology ,Targeted biopsy ,Prostate cancer ,Robotic Surgical Procedures ,Prostate ,Internal medicine ,medicine ,Humans ,Prospective Studies ,Prospective cohort study ,Reproducibility ,medicine.diagnostic_test ,business.industry ,Prostatic Neoplasms ,Reproducibility of Results ,Magnetic resonance imaging ,medicine.disease ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Radiology ,business ,Software - Abstract
Purpose Magnetic resonance imaging (MRI)/ultrasound-fusion prostate biopsy (FB) comprises multiple steps each of which can cause alterations in targeted biopsy (TB) accuracy leading to false-negative results. The aim was to assess the inter-operator variability of software-based fusion TB by targeting the same MRI-lesions by different urologists. Methods In this prospective study, 142 patients eligible for analysis underwent software-based FB. TB of all lesions (n = 172) were carried out by two different urologists per patient (n = 31 urologists). We analyzed the number of mismatches [overall prostate cancer (PCa), clinically significant PCa (csPCa) and non-significant PCa (nsPCa)] between both performed TB per patient. In addition we evaluated factors contributing to inter-operator variability by uni- and multivariable analyses. Results In 11.6% of all MRI-lesions (10.6% of all patients) there was a mismatch between TB1 and TB2 in terms of overall prostate cancer (PCa detection. Regarding csPCa, patient-based mismatch occurred in 14.8% (n = 21). Overall PCa and csPCa detection rate of TB1 and TB2 did not differ significantly on a per-patient and per-lesion level. Analyses revealed a smaller lesion size as predictive for mismatches (OR 9.19, 95% CI 2.02–41.83, p Conclusion Reproducibility and precision of targeting particularly small lesions is still limited although using software-based FB. Further improvements in image-fusion, segmentation, needle-guidance, and automatization are necessary.
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- 2021
46. Radiographic Measurement of Gastric Remnant Volume After Laparoscopic Sleeve Gastrectomy: Assessment of Reproducibility and Correlation with Weight Loss
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Wojciech Lisik, Marcin Błaż, Marek Gołębiowski, Piotr Palczewski, Małgorzata Deręgowska-Cylke, Radosław Cylke, Wojciech Szeszkowski, and Paweł Ziemiański
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Reproducibility ,Laparoscopic sleeve gastrectomy ,Nutrition and Dietetics ,Upper gastrointestinal series ,business.industry ,Endocrinology, Diabetes and Metabolism ,Radiography ,Reproducibility of Results ,Significant negative correlation ,Gastric remnant ,Obesity, Morbid ,Correlation ,Treatment Outcome ,Gastrectomy ,Weight loss ,Gastric Stump ,Weight Loss ,Humans ,Medicine ,Laparoscopy ,Surgery ,medicine.symptom ,Nuclear medicine ,business ,Retrospective Studies - Abstract
Background As a restrictive procedure, laparoscopic sleeve gastrectomy (LSG) relies primarily on the reduction of gastric volume. It has been suggested that an immediate postoperative gastric remnant volume (GRV) may influence long-term results of LSG; however, there are no consensus in this matter. The aim of this study was to assess the reproducibility of different radiographic methods of GRV calculation and evaluate their correlation with the weight loss (WL) after surgery. Methods This retrospective study evaluated 174 patients who underwent LSG in the period from 2014 to 2017. Using UGI, GRV was measured with 3 different mathematical methods by 2 radiologists. Intraobserver and interobserver calculations were made. Correlation between GRV and WL were estimated with calculations percentage of total weight loss (%TWL) and percentage of excess weight loss (%EWL) after 1, 3, 6, 12, 18, and 24 months postoperatively. Results During analysis of intraobserver similarities, the results of ICC calculation showed that reproducibility was good to excellent for all GRV calculation methods. The intraobserver reproducibility for Reader I was highest for cylinder and truncated cone formula and for Reader II for ellipsoid formula. The interobserver reproducibility was highest for ellipsoid formula. Regarding correlation between GRV and WL, significant negative correlation has been shown on the 12th month after LSG in %TWL and %EWL for every method of GRV calculation, most important for ellipsoid formula (%TWL – r(X,Y) = -0.335, p p Conclusion Radiographic methods of GRV calculation are characterized by good reproducibility and correlate with the postoperative WL. Graphical Abstract
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- 2021
47. Explaining and predicting human behavior and social dynamics in simulated virtual worlds: reproducibility, generalizability, and robustness of causal discovery methods
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Sinan Aksoy, Brett Jefferson, Ellyn Ayton, Svitlana Volkova, Dustin Arendt, Karthnik Shrivaram, Joseph Cottam, Emily Saldanha, and Maria Glenski
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Reproducibility ,General Computer Science ,Computer science ,business.industry ,Applied Mathematics ,General Decision Sciences ,Machine learning ,computer.software_genre ,Metaverse ,Computational Mathematics ,Social dynamics ,Robustness (computer science) ,Modeling and Simulation ,Generalizability theory ,Artificial intelligence ,business ,computer - Abstract
Ground Truth program was designed to evaluate social science modeling approaches using simulation test beds with ground truth intentionally and systematically embedded to understand and model complex Human Domain systems and their dynamics Lazer et al. (Science 369:1060–1062, 2020). Our multidisciplinary team of data scientists, statisticians, experts in Artificial Intelligence (AI) and visual analytics had a unique role on the program to investigate accuracy, reproducibility, generalizability, and robustness of the state-of-the-art (SOTA) causal structure learning approaches applied to fully observed and sampled simulated data across virtual worlds. In addition, we analyzed the feasibility of using machine learning models to predict future social behavior with and without causal knowledge explicitly embedded. In this paper, we first present our causal modeling approach to discover the causal structure of four virtual worlds produced by the simulation teams—Urban Life, Financial Governance, Disaster and Geopolitical Conflict. Our approach adapts the state-of-the-art causal discovery (including ensemble models), machine learning, data analytics, and visualization techniques to allow a human-machine team to reverse-engineer the true causal relations from sampled and fully observed data. We next present our reproducibility analysis of two research methods team’s performance using a range of causal discovery models applied to both sampled and fully observed data, and analyze their effectiveness and limitations. We further investigate the generalizability and robustness to sampling of the SOTA causal discovery approaches on additional simulated datasets with known ground truth. Our results reveal the limitations of existing causal modeling approaches when applied to large-scale, noisy, high-dimensional data with unobserved variables and unknown relationships between them. We show that the SOTA causal models explored in our experiments are not designed to take advantage from vasts amounts of data and have difficulty recovering ground truth when latent confounders are present; they do not generalize well across simulation scenarios and are not robust to sampling; they are vulnerable to data and modeling assumptions, and therefore, the results are hard to reproduce. Finally, when we outline lessons learned and provide recommendations to improve models for causal discovery and prediction of human social behavior from observational data, we highlight the importance of learning data to knowledge representations or transformations to improve causal discovery and describe the benefit of causal feature selection for predictive and prescriptive modeling.
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- 2021
48. Healthy Women and Men Do Not Show Differences in Tongue Strength and Regular Effort Saliva Swallows as Assessed by Piezo-Resistive Sensors: Results from a Reproducibility Study
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Gianluca Martinez, Monica Limoncino, Andrea Manca, Franca Deriu, Lucia Cugusi, Francesca Cadeddu, Marco Monticone, and Lucia Ventura
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Adult ,Male ,Intraclass correlation ,Isometric exercise ,Young Adult ,Speech and Hearing ,Tongue ,Swallowing ,Tip of the tongue ,Pressure ,medicine ,Humans ,Muscle Strength ,Saliva ,Orthodontics ,Reproducibility ,business.industry ,Gastroenterology ,Reproducibility of Results ,Deglutition ,Cross-Sectional Studies ,medicine.anatomical_structure ,Standard error ,Otorhinolaryngology ,Female ,business ,Body mass index - Abstract
The aim of this study was to establish the reproducibility of tongue strength measurements in healthy women and men during maximum anterior isometric pressure (MAIP) and regular effort saliva swallows (RESS). In this cross-sectional study, 30 healthy young adults were required to push with the tip of the tongue on a piezo-resistive sensor glued to the hard palate, immediately above the central incisor line. Tongue pressures exerted on the sensor during MAIP and spontaneous RESS were recorded. Participants underwent a retest procedure within the same session to verify the reproducibility of measurements, as determined by intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimum detectable change (MDC). Complete data were obtained from 30 subjects (15 women, 15 men; mean age 31.4 ± 7.8 years; mean weight 61.3 ± 9.4 kg). Compared to women, men showed a trend for generating larger MAIP (p = 0.06; d = 0.71) and RESS (p = 0.07; d = 0.69). After normalizing to body weight, height, and body mass index (BMI), such trends disappeared. At retest, MAIP and RESS proved stable and highly reliable (all ICCs ≥ 0.93) in men and women but associated to moderate variability as for SEM and MDC, with MAIP estimates associated to smaller SEM and MDC (SEM ranging 7.4-14.2%; MDC 18.6-20.9%) than RESS (SEM ranging 20.4-38.5%; MDC 52.5-55.6%). Piezo-resistive pressure sensors allow clinicians and researchers to perform reproducible measurements of tongue muscle performance. However, if therapeutic interventions are administered, measurement variability in tongue performance should be considered when appraising their clinical efficacy, especially for those populations who display impaired performance and may not be capable to generate high and stable forces. No gender-based differences emerged in the motor tasks tested.
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- 2021
49. Validation of the LUMIPULSE automated immunoassay for the measurement of core AD biomarkers in cerebrospinal fluid
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Else Huyck, Manu Vandijck, Andrea I Benet, Ondrej Lerch, Serge Gauthier, Martin Vyhnalek, Jakub Hort, Katerina Sheardova, Marcel M. Verbeek, Lucilla Parnetti, Alberto Lleó, Daniel Alcolea, Mira Chamoun, Jenna Stevenson, Nicholas J. Ashton, Tharick A. Pascoal, Katerina Cechova, Roberta Rinaldi, Pedro Rosa-Neto, Kaj Blennow, Samuela Cataldi, Ulf Andreasson, Johan Gobom, Giovanni Bellomo, Henrik Zetterberg, Jan Laczó, Neserine Rahmouni, Nathalie Le Bastard, and Marcus Clarin
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Clinical Biochemistry ,tau Proteins ,Diagnostic tools ,Meso scale ,03 medical and health sciences ,0302 clinical medicine ,Cerebrospinal fluid ,Alzheimer Disease ,medicine ,Humans ,immunoassay ,030304 developmental biology ,Immunoassay ,validation ,0303 health sciences ,Reproducibility ,Amyloid beta-Peptides ,LUMIPULSE ,medicine.diagnostic_test ,business.industry ,Biochemistry (medical) ,Reproducibility of Results ,biomarkers ,General Medicine ,Repeatability ,Alzheimer's disease ,Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3] ,Molecular biology ,Peptide Fragments ,3. Good health ,Csf biomarkers ,Automated immunoassay ,business ,Biomarkers ,030217 neurology & neurosurgery - Abstract
Objectives The core cerebrospinal fluid (CSF) biomarkers; total tau (tTau), phospho-tau (pTau), amyloid β 1-42 (Aβ 1-42), and the Aβ 1-42/Aβ 1-40 ratio have transformed Alzheimer’s disease (AD) research and are today increasingly used in clinical routine laboratories as diagnostic tools. Fully automated immunoassay instruments with ready-to-use assay kits and calibrators has simplified their analysis and improved reproducibility of measurements. We evaluated the analytical performance of the fully automated immunoassay instrument LUMIPULSE G (Fujirebio) for measurement of the four core AD CSF biomarkers and determined cutpoints for AD diagnosis. Methods Comparison of the LUMIPULSE G assays was performed with the established INNOTEST ELISAs (Fujirebio) for hTau Ag, pTau 181, β-amyloid 1-42, and with V-PLEX Plus Aβ Peptide Panel 1 (6E10) (Meso Scale Discovery) for Aβ 1-42/Aβ 1-40, as well as with a LC-MS reference method for Aβ 1-42. Intra- and inter-laboratory reproducibility was evaluated for all assays. Clinical cutpoints for Aβ 1-42, tTau, and pTau was determined by analysis of three cohorts of clinically diagnosed patients, comprising 651 CSF samples. For the Aβ 1-42/Aβ 1-40 ratio, the cutpoint was determined by mixture model analysis of 2,782 CSF samples. Results The LUMIPULSE G assays showed strong correlation to all other immunoassays (r>0.93 for all assays). The repeatability (intra-laboratory) CVs ranged between 2.0 and 5.6%, with the highest variation observed for β-amyloid 1-40. The reproducibility (inter-laboratory) CVs ranged between 2.1 and 6.5%, with the highest variation observed for β-amyloid 1-42. The clinical cutpoints for AD were determined to be 409 ng/L for total tau, 50.2 ng/L for pTau 181, 526 ng/L for β-amyloid 1-42, and 0.072 for the Aβ 1-42/Aβ 1-40 ratio. Conclusions Our results suggest that the LUMIPULSE G assays for the CSF AD biomarkers are fit for purpose in clinical laboratory practice. Further, they corroborate earlier presented reference limits for the biomarkers.
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- 2021
50. A novel method to measure margin reflex distance using the autorefractometer
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Demet Yolcu and Sibel Ozdogan
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Measure (data warehouse) ,Reproducibility ,business.industry ,Intraclass correlation ,Margin reflex distance ,Eyelids ,Reproducibility of Results ,Digital photography ,Repeatability ,Ophthalmology ,Digital image ,Reflex ,Image Processing, Computer-Assisted ,Photography ,Humans ,Medicine ,Nuclear medicine ,business ,Reliability (statistics) - Abstract
PURPOSE To determine the margin reflex distance (MRD) in healthy subjects using autorefractometer front monitor images (ARFMI) and validate the accuracy of this method by comparing it with conventional methods. METHODS One hundred eyes of 50 healthy subjects aged 20-59 years were included in the study. Autorefractometer front monitor images were video-recorded using a smartphone camera, and screenshots were taken to analyze the MRD. The results were compared with those from conventional methods to determine the reliability of the method. To evaluate the repeatability and reproducibility of all measurement methods, we performed two different visits by two observers. RESULTS The mean MRD-1 of the autorefractometer image measurement was 4.29 ± 0.90 mm, mean MRD-1 of the of the digital photography image measurement was 3.78 ± 1.03 mm, and mean MRD-1 of the manual measurement was 4.02 ± 1.09 mm. The mean difference (MD) of MRD-1 was analyzed and it was found that MD of the autorefractometer image was significantly higher than the MD of other groups (p
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- 2021
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