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Introduction Photoplethysmography (PPG) in wearable sensors potentially plays an important role in accessible heart rhythm monitoring. We investigated the accuracy of a state-of-the-art bracelet (Corsano 287) for heartbeat detection in cardiac patients and evaluated the efficacy of a signal qualifier in identifying medically useful signals. Methods Patients from an outpatient cardiology clinic underwent a simultaneous resting ECG and PPG recording, which we compared to determine accuracy of the PPG sensor for detecting heartbeats within 100 and 50 ms of the ECG-detected heart beats and correlation and Limits of Agreement for heartrate (HR) and RR-intervals. We defined subgroups for skin type, hair density, age, BMI and gender and applied a previously described signal qualifier. Results In 180 patients 7914 ECG-, and 7880 (99%) PPG-heartbeats were recorded. The PPG-accuracy within 100 ms was 94.6% (95% CI 94.1–95.1) and 89.2% (95% CI 88.5–89.9) within 50 ms. Correlation was high for HR (R = 0.991 (95% CI 0.988–0.993), n = 180) and RR-intervals (R = 0.891 (95% CI 0.886–0.895), n = 7880). The 95% Limits of Agreement (LoA) were −3.89 to 3.77 (mean bias 0.06) beats per minute for HR and −173 to 171 (mean bias −1) for RR-intervals. Results were comparable across all subgroups. The signal qualifier led to a higher accuracy in a 100 ms range (98.2% (95% CI 97.9–98.5)) (n = 143). Conclusion We showed that the Corsano 287 Bracelet with PPG-technology can determine HR and RR-intervals with high accuracy in cardiovascular at-risk patient population among different subgroups, especially with a signal quality indicator.

Purpose To evaluate the repeatability of aphakic intraoperative wavefront aberrometry and compare it to pre- and postoperative aberrometry. Setting Department of Ophthalmology, Hanusch Hospital, Vienna, Austria DESIGN:: Prospective case series METHODS:: Thirty eyes of 30 patients scheduled for cataract surgery were each measured three consecutive times via Shack-Hartmann wavefront sensing (SH-WFS) preoperatively, intraoperatively in aphakia, and 2-months postoperatively after IOL implantation by a single examiner. Intra-class correlation coefficients (ICC) of spherical equivalent (SE) values were evaluated for each time point. Intrasubject standard deviation (Sw) as repeatability (Sr) with corresponding repeatability limit (1.96 ?2 x Sw) were further assessed. Additionally, mean SE differences with corresponding limits of agreement (LoA) were calculated for comparison. Results A high consistency of repeated measurements was found with ICCs above 0.9 for each of the three time-points. Intra-observer repeatability (Sr) and repeatability limit (r) of intraoperative aberrometry SE measurements were 0.34 and 0.95 D, respectively. The LoA for intraoperative aphakic SE across three consecutive measurements were -0.71 to +0.85 D. For comparison, Sr and r for phakic preoperative measurements in the cataractous state as well as postoperative measurements in the pseudophakic state were 0.33 and 0.93 D as well as 0.23 and 0.64 D, respectively. Similarly, the LoA for pre- and postoperative SE measurements were -0.66 to +0.60 D and -0.27 to +0.45 D, respectively. Conclusion Shack-Hartmann wavefront sensing test-retest reliability was high for all three time points, but the intraoperative setting resulted in a lower repeatability and broadened the agreement range.

The study aimed to investigate the relationship between anaerobic capacity, mechanical and anaerobic contribution during the 30-s Wingate Anaerobic Test (30sWAnT). After familiarization, fifteen, male recreational mountain biking practitioners underwent the following sequence of tests: 1) a graded exercise test to determine maximal oxygen uptake and associated intensity iV˙O2max; 2 and 3) supramaximal exhaustive effort at 115% of iVO2max and 30sWAnT, performed randomly. The glycolytic and phosphagen pathways measured during the supramaximal effort were significantly correlated with peak power (r = 0.85; p < 0.01 and r = 0.57; p = 0.02, respectively), mean power (r = 0.78; p < 0.01 and r = 0.69; p < 0.01, respectively), and total work (r = 0.78; p < 0.01 and r = 0.69; p< 0.02, respectively) measured during the 30sWAnT. A significant correlation was also found between anaerobic capacity and peak power (r = 0.88; p < 0.01), mean power (r = 0.89; p < 0.01), and total work (r = 0.89; p < 0.01). Additionally, anaerobic capacity estimated during the supramaximal effort and the anaerobic contribution measured during the 30sWAnT were not different (p = 0.44) and presented significant good reliability and association (ICC = 0.84; p = 0.001) and good agreement, evidenced by the mean of differences and 95% limits of agreement near to zero (mean bias = 0.11). The results suggest that glycolytic and phosphagen capacity were associated with mechanical performance in the 30sWAnT. In addition, anaerobic contribution during the 30sWAnT seems to be valid for estimating anaerobic capacity in recreational mountain bike cyclists, as well as to estimate the glycolytic and phosphagen contributions.

Twenty‐four‐hour urine collection is the gold standard method for the evaluation of salt intake, but it is often impractical in large‐scale investigations, especially in resource‐poor areas. Methods for the estimation of 24‐hour urinary sodium excretion (USE) using a spot urine sample have been established, but have not been validated in Chinese Tibetans. Therefore, the authors aimed to evaluate the Kawasaki, Tanaka, and the International Cooperative Study on Salt, Other Factors, and Blood Pressure (INTERSALT) formulas for the prediction of 24‐hour USE in Chinese Tibetan adults. The authors analyzed the bias, correlation, agreements between estimated values and measured values, and the relative and absolute differences and misclassification at the individual level for the three methods in 323 Tibetan participants from the Ganzi Tibetan Autonomous Prefecture of Sichuan Province, China. The mean biases between the measured values and the estimated 24‐hour USE using the Kawasaki, Tanaka, and INTERSALT methods were 5.4 mmol/day (95% confidence interval [CI]: 0.8–10.1 mmol/day), −40.8 mmol/day (95% CI: −44.6 to −36.9 mmol/day), and −57.1 mmol/day (95% CI: −61.9 to −52.4 mmol/day), respectively. The Pearson correlation coefficients for the relationships between the measured values and the estimated 24‐hour USE were 0.43 (Kawasaki), 0.38 (Tanaka), and 0.27 (INTERSALT), respectively (all p

Purpose Patients with repaired Tetralogy of Fallot (rTOF) will develop dilation of the right ventricle (RV) from chronic pulmonary insufficiency and require pulmonary valve replacement (PVR). Cardiac MRI (cMRI) is used to guide therapy but has limitations in studying novel intracardiac flow parameters. This pilot study aimed to demonstrate feasibility of reconstructing RV motion and simulating intracardiac flow in rTOF patients, exclusively using conventional cMRI and an immersed-boundary method computational fluid dynamic (CFD) solver. Methods Four rTOF patients and three normal controls underwent cMRI including 4D flow. 3D RV models were segmented from cMRI images. Feature-tracking software captured RV endocardial contours from cMRI long-axis and short-axis cine stacks. RV motion was reconstructed via diffeomorphic mapping (Deformetrica, deformetrica.org), serving as the domain boundary for CFD. Fully-resolved direct numerical simulations were performed over several cardiac cycles. Intracardiac vorticity, kinetic energy (KE) and turbulent kinetic energy (TKE) was measured. For validation, RV motion was compared to manual tracings, results of KE were compared between CFD and 4D flow. Results Diastolic vorticity and TKE in rTOF patients were 4.12¿±¿2.42 mJ/L and 115¿±¿27/s, compared to 2.96¿±¿2.16 mJ/L and 78¿±¿45/s in controls. There was good agreement between RV motion and manual tracings. The difference in diastolic KE between CFD and 4D flow by Bland-Altman analysis was - 0.89910 to 2 mJ/mL (95% limits of agreement: - 1.351¿×¿10-2 mJ/mL to 1.171¿×¿10-2 mJ/mL). Conclusion This CFD framework can produce intracardiac flow in rTOF patients. CFD has the potential for predicting the effects of PVR in rTOF patients and improve the clinical indications guided by cMRI.

AIM Accurate and precise estimation of glomerular filtration rate (GFR) is essential in kidney disease. We evaluated the usefulness of the mean of creatinine clearance (CCr ) and urea clearance (CUN ) examined over a 1-h urine collection period (1-h (CCr + CUN )/2) in a retrospective, cross-sectional study across two centres, as a relatively simple method for estimating GFR in children. METHODS Children aged ≤18 years who underwent inulin clearance (CIn ) tests were eligible. Two clearance values were obtained during a 2-h test consisting of two periods of 1 h each. The mean clearance in two periods was defined as 1-h clearance. 1-h (CCr + CUN )/2, 1-h CCr , 1-h CUN and GFR estimated by Cr-based and cystatin C (CysC)-based formulas for Japanese children were compared with CIn . Bland-Altman plots were used to evaluate correlations. The primary outcome measure was the correlation between 1-h (CCr + CUN )/2 and CIn . RESULTS Fifty-three children were analysed. Their median age was 10.9 (interquartile range [IQR] 5.3-14.2) years, and median CIn and 1-h (CCr + CUN )/2 were 77.0 (IQR: 51.5-95.1) and 81.0 (IQR: 64.1-97.7) ml/min/1.73 m2 , respectively. Percentage difference of CIn and 1-h (CCr + CUN )/2 in the Bland-Altman plot was -11.2% (95% confidence interval - 15.3% - -7.1%), with 95% lower and upper limits of agreement of -40.3% and 18.0%, respectively. Thus, 1-h (CCr + CUN )/2 was 1.12 times CIn . CONCLUSION 1 h (CCr + CUN )/2 was almost concordant with CIn . 1-h (CCr + CUN )/2 can estimate GFR accurately and precisely, making it a simple and speedy test for use in clinical practice.

To compare keratometry data between the handheld Retinomax K-plus 3 and the table-mounted IOLMaster 700. Healthy adult volunteers were prospectively recruited to the study. All participants underwent 3 consecutive keratometry measurements using the Retinomax K-plus 3 and a single biometry assessment using the IOLMaster 700. Differences between the Retinomax K-plus 3 and the IOLMaster 700 were assessed using Wilcoxon test for paired samples, Spearman correlation, Bland–Altman and mountain plots. Twenty-eight healthy subjects with a median age of 37 years (interquartile range (IQR) 28–44 years) were included in the study. The median mean keratometry (mean K) reading was higher using the Retinomax K-plus 3 (44.04D; IQR 42.96–45.61D) compared to the IOLMaster 700 (43.78D; IQR 43.22–44.90D, p

Background Monitoring blood glucose concentrations is common in critically ill neonatal foals, especially septic foals and those receiving naso-esophageal feedings or IV parenteral nutrition. Glucose typically is measured using a point-of-care (POC) glucometer but requires repeated restraint and blood collections, which may cause irritation at venipuncture sites and increased demands on nursing staff. Continuous glucose monitoring systems (CGMS) may provide an accurate alternative for monitoring blood glucose concentration. Objectives To determine the correlation and accuracy of a CGMS to monitor neonatal foals' blood glucose concentrations as compared to a POC glucometer and laboratory chemistry analysis (CHEM). Animals Samples from 4 healthy and 4 ill neonatal foals. Methods A CGMS was placed on each foal, and glucose measurements acquired from this device were compared to simultaneous measurements of blood glucose concentration using a POC glucometer and CHEM. Results Two-hundred matched glucose measurements were collected from 8 neonatal foals. The mean bias (95% limits of agreement) between CGMS and CHEM, CGMS and POC glucometer, and POC glucometer and CHEM was 3.97 mg/dL (-32.5 to 40.4), 18.2 mg/dL (-28.8 to 65.2), and 22.18 mg/dL (-9.3 to 53.67), respectively. The Pearson's correlation coefficient (r) was significantly correlated among all devices: GCMS and CHEM (r = 0.81), CGMS and POC glucometer (r = 0.77) and POC glucometer-CHEM (r = 0.92). Conclusions and clinical importance Within the blood glucose concentration ranges in this study (78-212 mg/dL), CGMS measurements were significantly correlated with CHEM, suggesting that it is an acceptable method to provide meaningful, immediate, and continuous glucose concentration measurements in neonatal foals while eliminating the need for repeated restraint and blood collection.

Background Two previous reports from the same group concluded that the analytical reliability of Instrumentation Laboratory GEM4000 analyzers (GEM4K) deteriorated during a 24-hour period, based on results between samples from the same patient but collected at different times. Our routine blood gas Between-Laboratory Survey is done every 2 weeks using a freshly pooled heparinized blood sample taken to each analyzer location to verify comparability among our GEM4K and Radiometer ABL90 (Rad90) blood gas analyzers. Because another report found a few very large differences in glucose results between the GEM4K and central laboratory analyzers, we reviewed the glucose results on plasma from our Chemistry Between-Laboratory Surveys that includes comparisons between our central laboratory analyzers (Beckman DxC800; DxC800) and our GEM4K and Rad90 blood gas analyzers. Method Using data from our Blood Gas and Chemistry Surveys over a 55-week period, we calculated the mean, standard deviation (SD), and concentration intervals of the 27 sets of results by the GEM4K or Rad90 analyzers. Agreement in plasma glucose between DxC800 and blood gas analyzers was evaluated by the limits of agreement and intraclass correlation coefficient analysis. Results For each analyte, the Rad90 had lower average SD than the GEM4K for the 55-week period, although both brands of analyzers showed acceptable performance. For plasma glucose results on our Chemistry Survey, the GEM4K results agreed more closely with the DxC800 results than the Rad90 results. Conclusions Based on both our Blood Gas and Chemistry Surveys, we conclude that both brands of analyzers performed within analytically and clinically acceptable limits throughout the year, with no evidence for the type of errors reported previously.

To compare the self-assessment of surgical residents and observers (faculty members and nurses) during laparoscopic cholecystectomy (LC).A prospective observational study was conducted between February 2020 and July 2020 at a medical school hospital. Seventy-four LC surgeries were performed by surgical residents in the presence of faculty members. A self-assessment of the technical and nontechnical performance of the residents was requested. The self-assessment of residents was compared with observer evaluations using the Kruskal-Wallis test. Gwet AC2 fit coefficient was used to determine the consistency between the observers' and residents' assessments. Bland-Altman plots were generated with 95% limits of agreement to describe the agreement between the total scores of the observers.The self-assessment of residents had a statistically significant higher score when compared with observers (faculty and nurses) (P0.001). However, no significant difference was observed between the total scores given by the observers (faculty members and nurses) (P0.05). There was a moderate agreement between the resident versus faculty members [0.503; 95% confidence interval (CI), 0.430-0.576] and resident versus nurse (0.518; 95% CI, 0.432-0.605) when evaluating technical skills. However, there was substantial agreement between faculty members and nurses (0.736; 95% CI, 0.684-0.789). Postoperative pain was significantly correlated with resident self-assessment (P=0.022).The self-assessment scores of surgical residents in LC operations were overestimated compared with observer assessments.

4D phase contrast magnetic resonance imaging (PC-MRI) allows for the visualization and quantification of the cerebral blood flow. A drawback of software that is used to quantify the cerebral blood flow is that it oftentimes assumes a static arterial luminal area over the cardiac cycle. Quantifying the lumen area pulsatility index (aPI), i.e. the change in lumen area due to an increase in distending pressure over the cardiac cycle, can provide insight in the stiffness of the arteries. Arterial stiffness has received increased attention as a predictor in the development of cerebrovascular disease. In this study, we introduce software that allows for measurement of the aPI as well as the blood flow velocity pulsatility index (vPI) from 4D PC-MRI. The internal carotid arteries of seven volunteers were imaged using 7 T MRI. The aPI and vPI measurements from 4D PC-MRI were validated against measurements from 2D PC-MRI at two levels of the internal carotid arteries (C3 and C7). The aPI and vPI computed from 4D PC-MRI were comparable to those measured from 2D PC-MRI (aPI: mean difference: 0.03 (limits of agreement: −0.14 – 0.23); vPI: 0.03 (−0.17–0.23)). The measured blood flow rate for the C3 and C7 segments was similar, indicating that our proposed software correctly captures the variation in arterial lumen area and blood flow velocity that exists along the distal end of the carotid artery. Our software may potentially aid in identifying changes in arterial stiffness of the intracranial arteries caused by pathological changes to the vessel wall.

Tricuspid regurgitation is associated with a poor outcome and its quantification remains a challenge. Tricuspid annulus dilatation is one of the parameters that influences clinical decision-making. The aim of this study was to compare the use of 2D transoesophageal echocardiography with surgical assessment for the measurement of the tricuspid annulus. Sixty-one cardiac patients (median age 64 years) were included in the study. Echocardiographic tricuspid annulus measurements were obtained from four chamber and transgastric short axis views and compared with the surgical measurements of this valve. The study was approved by the Ethics Committee of our institution. The tricuspid annulus measurements were obtained from the four chamber and the short axis views in 57 and 49 patients, respectively, while surgical measurement was performed in all 61 patients. Bland–Altman analysis of 49 tricuspid annulus-matched dimensions of the short axis view and surgical values showed a mean bias of 0.223 mm/m2, with limits of agreement of −5.86 to 6.31 mm/m2. Echocardiographic measurements of the tricuspid annulus dimension were accurate (90% sensitivity and 90% specificity for a four chamber view cut-off value ≥ 24.5 mm/m2, and 89% sensitivity and 97% specificity for a short axis view cut-off value ≥ 37.6 mm/m2, P

BACKGROUND/OBJECTIVE: Visceral adipose tissue (VAT) is a key target of interventions for obesity-related diseases. Dual-energy x-ray absorptiometry (DXA) can estimate VAT, however its accuracy to measure longitudinal change in VAT compared to gold-standard techniques such as magnetic resonance imaging (MRI), has not been studied in adults. This study aimed to determine the accuracy of DXA compared with gold-standard MRI for cross-sectional VAT assessment, and for detecting longitudinal change in VAT. METHODS: Adults with coronary artery disease (64 ± 8 years; BMI 27.8 ± 3.5 kg/m2; 88% male) were assessed for VAT by DXA and MRI at baseline (n = 34) and during implementation of an exercise intervention study at 3- and 12-months (n = 29). To match the 5.2 cm DXA measurement site for Hologic software (InnerCoreTM), VAT cross-sectional area (CSA) was measured by MRI using a single slice at L4/L5 junction, and VAT volume measured by 10 × 5 mm slices over the L4/L5 junction. MRI slices were quantified for VAT using semi-automated specialised software. Relationships between DXA and MRI for cross-sectional VAT and longitudinal change in VAT were determined by linear regression. Accuracy between the methods was assessed by Bland-Altman analysis, with data presented as mean difference (95% confidence interval), lower and upper limits of agreement (LoA). RESULTS: Strong correlations were found between DXA-VAT and MRI-VAT at baseline (r = 0.90; p

Background Measuring blood pressure in patients with obesity is challenging. The ClearSight™ finger cuff (FC) uses the vascular unloading technique to provide continuous non-invasive blood pressure measurements. We aimed to test the agreement of the FC with invasive radial arterial monitoring (INV) in patients with obesity. Methods Participants had a body mass index (BMI) ≥45 kg/m2 and underwent laparoscopic bariatric surgery. FC and INV measurements were obtained simultaneously every 5 min on each patient, following induction of anesthesia. Agreement over time was assessed using modified Bland-Altman plots and error grid analysis permitted clinical interpretation of the results. Four-quadrant plots allowed assessment of concordance in blood pressure changes. Results The 30 participants had a median (IQR) BMI of 50.2 kg/m2 (IQR 48.3–55.3). The observed bias (SD, 95% limits of agreement) for systolic blood pressure (SBP) was 14.3 mmHg (14.1, -13.4 – 42.0), 5.2 mmHg (10.9, -16.0 – 26.5) for mean arterial pressure (MAP) and 2.6 mmHg (10.8, -18.6 – 23.8) for diastolic blood pressure (DBP). Error grid analysis showed that the proportion of readings in risk zones A-E were 90.8, 6.5, 2.7, 0 and 0% for SBP and 91.4, 4.3, 4.3, 0 and 0% for MAP, respectively. Discordance occurred in ≤8% of pairs for consecutive change in SBP, MAP and DBP. Conclusions The vascular unloading technique was not adequately in agreement with radial arterial monitoring. Evaluation in a larger sample is required before recommending this technique for intraoperative monitoring of patients with BMI ≥45 kg/m2.

Objective To compare values of haemoglobin concentration (SpHb), arterial haemoglobin saturation (SpO2) and calculated arterial oxygen content (SpOC), measured noninvasively with a pulse co-oximeter before and after in vivo adjustment (via calibration of the device using a measured haemoglobin concentration) with those measured invasively using a spectrophotometric-based blood gas analyser in anaesthetized dogs. Study design Prospective observational clinical study. Animals A group of 39 adult dogs. Methods In all dogs after standard instrumentation, the dorsal metatarsal artery was catheterised for blood sampling, and a pulse co-oximeter probe was applied to the tongue for noninvasive measurements. Paired data for SpHb, SpO2 and SpOC from the pulse co-oximeter and haemoglobin arterial oxygen saturation (SaO2) and arterial oxygen content (CaO2) from the blood gas analyser were obtained before and after in vivo adjustment. Bland–Altman analysis for repeated measurements was used to evaluate the bias, precision and agreement between the pulse co-oximeter and the blood gas analyser. Data are presented as mean differences and 95% limits of agreement (LoA). Results A total of 39 data pairs were obtained before in vivo adjustment. The mean invasively measured haemoglobin–SpHb difference was –2.7 g dL−1 with LoA of –4.9 to –0.5 g dL−1. After in vivo adjustment, 104 data pairs were obtained. The mean invasively measured haemoglobin–SpHb difference was –0.2 g dL−1 with LoA of –1.1 to 0.6 g dL−1. The mean SaO2–SpO2 difference was 0.86% with LoA of –0.8% to 2.5% and that between CaO2–SpOC was 0.66 mL dL–1 with LoA of –2.59 to 3.91 mL dL–1. Conclusions Before in vivo adjustment, pulse co-oximeter derived values overestimated the spectrophotometric-based blood gas analyser haemoglobin and CaO2 values. After in vivo adjustment, the accuracy, precision and LoA markedly improved. Therefore, in vivo adjustment is recommended when using this device to monitor SpHb in anaesthetised dogs.

Objective The rapid development of artificial intelligence technologies for medical imaging has recently enabled automatic identification of anatomical landmarks on radiographs. The purpose of this study was to compare the results of an automatic cephalometric analysis using convolutional neural network with those obtained by a conventional cephalometric approach. Material and methods Cephalometric measurements of lateral cephalograms from 35 patients were obtained using an automatic program and a conventional program. Fifteen skeletal cephalometric measurements, nine dental cephalometric measurements, and two soft tissue cephalometric measurements obtained by the two methods were compared using paired t test and Bland-Altman plots. Results A comparison between the measurements from the automatic and conventional cephalometric analyses in terms of the paired t test confirmed that the saddle angle, linear measurements of maxillary incisor to NA line, and mandibular incisor to NB line showed statistically significant differences. All measurements were within the limits of agreement based on the Bland-Altman plots. The widths of limits of agreement were wider in dental measurements than those in the skeletal measurements. Conclusions Automatic cephalometric analyses based on convolutional neural network may offer clinically acceptable diagnostic performance. Careful consideration and additional manual adjustment are needed for dental measurements regarding tooth structures for higher accuracy and better performance.

Objectives The main objective of this study was to determine the concurrent validity between a hand-held (HHD) and mounted hand-held dynamometer (MHHD) for assessing isometric neck strength. Design Observational design. Setting Semiprofessional rugby club Participants Nineteen semi-professional rugby players (age = 26 ± 5 years, stature = 186.5 ± 6.5 cm, body mass = 98.7 ± 12.8 kg). Main outcome measures Concurrent validity (limits of agreement, correlation) between HHD and MHHD, the intrarater reliability (intra-class correlation, ICC) and comparison between playing positions. Results Absolute peak and mean peak force were systematically lower when using the HHD compared to MHHD, with the mean bias ranging from -1.8 to -3.8 kgf (P < 0.05). Differences were not evident for flexion when applying the correction equations (-0.5 to 2.1 kgf, P > 0.05) but remained for extension. Correlations between methods were large-to-very large; the ICCs for both methods were good (ICC = 0.72-0.89), with no difference between positions (P < 0.05). Conclusion The concurrent validity of HHD was considered acceptable when compared to the MHHD and the correction equation applied. Both methods are reliable and useful for assessing neck strength in rugby players, though, caution is needed when determining strength during neck extension.

Compressed SENSE (C-SENSE) allows more rapid MRI acquisition through incoherent, pseudorandom k-space undersampling. The purpose of our study was to compare conventional sensitivity encoded imaging (SENSE) quantitative MR images to those obtained using C-SENSE for measurement of liver proton density fat fraction (PDFF), T2*, and stiffness. Clinical liver MRI examinations that included SENSE and C-SENSE quantitative MRI sequences were retrospectively identified. Patient age, gender, liver PDFF (%), T2* (ms), and stiffness (kPa) were recorded. Spearman’s rank-order correlation (r) was used to evaluate association between methods, and Bland–Altman analysis was used to determine the mean bias and 95% limits of agreement. Clinical liver MRI examinations that included SENSE and C-SENSE quantitative MRI sequences were retrospectively identified. Patient age, gender, liver PDFF (%), T2* (ms), and stiffness (kPa) were recorded. Spearman’s rank-order correlation (r) was used to evaluate association between methods, and Bland–Altman analysis was used to determine the mean bias and 95% limits of agreement. Thirty-six examinations met the inclusion criteria. Mean patient age was 15.7 ± 7.7 years; twelve exams (33%) were in female patients. Liver PDFF showed very strong positive correlation (r = 0.98) between sequences, with a mean bias of 0.28% (95% LOA: -0.85, 1.41%). T2* showed moderate positive correlation (r = 0.53), with a mean bias of − 3.0 ms (95% LOA: − 12.0, 6.0 ms). Stiffness showed very strong positive correlation (r = 0.97), with a mean bias of 0.13 kPa (95% LOA: − 0.37, 0.63 kPa) that increased with increasing liver stiffness. There were strong positive correlations between SENSE and C-SENSE MRI measurements of liver PDFF and stiffness, with no to minimal bias. However, there was moderate correlation and greater negative mean bias between T2* measurements. Our results demonstrate the potential of compressed sensing to reliably measure PDFF and stiffness in the clinic.

AIM: To compare the results of visual acuity (VA) measured by Early Treatment Diabetic Retinopathy Study (ETDRS) chart, 5 m Standard Logarithm Visual Acuity (5SL) chart, and 2.5 m Standard Logarithm Visual Acuity (2.5SL) chart in outpatients of age 12-80y. METHODS: Each patient (totally 2000 outpatients) had both eyes tested with ETDRS chart at 4 m, 5SL chart at 5 m, and 2.5SL chart at 2.5 m in random order. The VA values of outpatients were categorized by ages. VA values were expressed by logMAR recording method. RESULTS: The mean VA results of ETDRS charts, 5SL, and 2.5SL chart were 0.52±0.28, 0.50±0.30, and 0.46±0.28 logMAR, respectively. There was a statistically significant difference in the three eye charts in the whole group (P

AIM To assess different techniques to measure body composition in paediatric patients with inflammatory bowel disease using dual energy X-ray absorptiometry as a reference method. We hypothesised that a three-compartment model may demonstrate superiority over other methods as skinfold thickness equations and bioelectrical impedance analysis. METHODS Body composition was assessed using skinfold thickness equations, bioelectrical impedance analysis and the three-compartment model. Data obtained with these methods were compared to the results obtained by dual energy X-ray absorptiometry. Statistical analysis was performed using Spearman's correlation and Bland-Altman's limits of agreement method. RESULTS Twenty-one paediatric patients with inflammatory bowel disease were included: 11 females and 10 males; mean age for the entire group: 14.3 years, range 12-16 years. In children with inflammatory bowel disease, skinfold thickness equations, bioelectrical impedance analysis and the three-compartment model showed reliable measurements with small differences in the percentage of total body fat and good limits of agreements. CONCLUSION The assessment of body composition using bioelectrical impedance analysis provides a valid and accurate method in children with inflammatory bowel disease as compared to dual energy X-ray absorptiometry. In the future, superiority of 3-compartment model in research and clinical settings of nutritional intervention and disease status in children with inflammatory bowel disease remains to be demonstrated.

PURPOSE To evaluate the agreement between different parameters obtained with 2 swept-source optical coherence tomography (SS-OCT)-based biometers and 1 Scheimpflug camera with partial coherence interferometry (PCI). SETTING Single center, Oftalvist, Alicante, Spain. DESIGN Prospective case series. METHODS Biometry was performed in 49 eyes using 3 optical biometers: ANTERION SS-OCT, IOLMaster 700 SS-OCT, and Pentacam AXL PCI. Keratometry (K), J0 and J45 vectors, anterior chamber depth (ACD), central corneal thickness (CCT), white-to-white (WTW), lens thickness (LT), and axial length (AL) were measured with each device. Bland-Altman analysis was applied. RESULTS This study comprises 49 eyes of 49 patients. There were no statistically significant differences for K1, K2, J0 and J45 between the 3 devices (P > .9). In contrast, there was a statistically significant difference in the ACD, CCT, WTW, LT, and AL between the biometers (P < .001). Specifically, there was a statistically significant difference between ACD, CCT, and WTW values for all-pairwise comparisons. IOLMaster showed the shortest ACD value and ANTERION showed the largest ACD. IOLMaster showed the highest CCT and Pentacam showed the lowest CCT. IOLMaster showed the largest WTW and Pentacam showed the shortest WTW. The LT measured with IOLMaster was thicker than that measured with ANTERION. There was a statistically significant difference in the AL between IOLMaster and Pentacam, with a shorter AL measured with IOLMaster (P < .001), but no differences were found between ANTERION and IOLMaster (P = .599) and between ANTERION and Pentacam (P = .054). CONCLUSIONS Mean differences and the limits of agreement obtained in all-pairwise comparisons of the different parameters should be judged clinically to consider the interchangeability of these devices.

Comparing the diagnostic utility of salivary specimen samples with conventional nasopharynx-oropharynx (NP-OP) specimen samples to identify COVID-19 cases by reverse transcription-polymerase chain reaction (RT-PCR). Eighty COVID-19 suspects enrolled for the paired sampling. In addition to conventional sampling, suspects were asked to follow stepwise pictorial instructions for self salivary sampling. Separate nylon swab stick was used for taking the samples from NP-OP and the floor of the oral cavity. The data were analyzed for sensitivity, specificity, concordance of COVID-19 status, and limits of agreement for cycle threshold (ct) values by either method. Forty-nine suspects (61.3%) were males, the mean age was 36.4 years. To determine the diagnostic test performance of the saliva, RT-PCR results of the NP-OP samples were used as the reference standard. Out of 80 suspects, 41 showed positivity by NP-OP swabs and 12 by salivary samples. The salivary samples showed significantly lesser positivity rate. The sensitivity and specificity of salivary samples against conventional reference standards are 24.4%, 94.9% respectively. Concordance of these two types of samples in terms of agreement kappa statistics is estimated as K = 0.252 (0.09–0.42). Median ct values of both the E and ORF1ab gene for the salivary samples were higher compared to the corresponding NP-OP sample. This study showed lesser sensitivity with salivary swab samples as compared to conventional NP-OP sampling for RT-PCR, COVID-19 detection. Hence, we are of opinion that more studies are required to establish the utility of salivary sampling in COVID-19 diagnostics.

Background The solid portion size of lung cancer lesions manifesting as subsolid lesions is key in their management, but the automatic measurement of such lesions by means of a deep learning (DL) algorithm needs evaluation. Purpose To evaluate the performance of a commercially available DL algorithm for automatic measurement of the solid portion of surgically proven lung adenocarcinomas manifesting as subsolid lesions. Materials and Methods Surgically proven lung adenocarcinomas manifesting as subsolid lesions on CT images between January 2018 and December 2018 were retrospectively included. Five radiologists independently measured the maximal axial diameter of the solid portion of lesions. The DL algorithm automatically segmented and measured the maximal axial diameter of the solid portion. Reader measurements, software measurements, and invasive component size at pathologic examination were compared by using intraclass correlation coefficient (ICC) and Bland-Altman plots. Results A total of 448 patients (mean age, 63 years ± 10 [standard deviation]; 264 women) with 448 lesions were evaluated (invasive component size, 3-65 mm). The measurement agreements between each radiologist and the DL algorithm were very good (ICC range, 0.82-0.89). When a radiologist was replaced with the DL algorithm, the ICCs ranged from 0.87 to 0.90, with an ICC of 0.90 among five radiologists. The mean difference between the DL algorithm and each radiologist ranged from -3.7 to 1.5 mm. The widest 95% limit of agreement between the DL algorithm and each radiologist (-15.7 to 8.3 mm) was wider than pairwise comparisons of radiologists (-7.7 to 13.0 mm). The agreement between the DL algorithm and invasive component size at pathologic evaluation was good, with an ICC of 0.67. Measurements by the DL algorithm (mean difference, -6.0 mm) and radiologists (mean difference, -7.5 to -2.3 mm) both underestimated invasive component size. Conclusion Automatic measurements of solid portions of lung cancer manifesting as subsolid lesions by the deep learning algorithm were comparable with manual measurements and showed good agreement with invasive component size at pathologic evaluation. © RSNA, 2021 Online supplemental material is available for this article.

Refereed/Peer-reviewed Objectives: Maximal aerobic speed (MAS) may be predicted from 2.0 km time trial (TT) running speed in male Australian Rules football (AF) players. Given the between-sex differences in physiological variables precursory to endurance performance, and the impact of this on MAS distance limit, this study determined running speed across various TT distances best approximating MAS in female AF players. Method: 33 female AF players completed assessments of MAS and TT performance separated by at least 48 h. In a randomised order, half of the athletes completed TT distances of 1.2, 1.6 and 2.0 km, and the other half completed distances of 1.4, 1.8 and 2.2 km. Bias, limits of agreement (LOA) and linear mixed modelling determined agreement between TT-derived running speed and MAS. Results: Average speed for all TT distances were different to MAS (bias≥0.59 ± 0.45 km·h−1; p ≤ 0.015) with the exception of the 1.4 km TT (bias = −0.12 ± 0.26 km·h−1; p = 0.34). LOA was narrowest for the 1.4 km TT(±0.76 km·h−1; ±6.1%) compared to other TT distances (±0.82–1.67 km·h−1; ±6.7–12.9%). A significant linear association between bias and TT distance (r = −0.73; p < 0.001) indicated TT speed would be equal to MAS when a 1.4–1.5 km TT was completed, and that MAS may be predicted from any distance between 1.2 and 2.2 km. Conclusions: MAS was best approximated by a 1.4–1.5 km TT in female AF players, but may be predicted from TT speed for any distance between 1.2 and 2.2 km. TT-derived MAS provides a time and resource efficient method for the quantification of aerobic fitness and prescription of future training intensities.

BackgroundABG samples are often obtained in trauma patients to assess shock severity. Venous blood gas (VBG) sampling, which is less invasive, has been widely used to assess other forms of shock. The study aim was to determine the agreement between VBG and ABG measurements in trauma.MethodsPatients were enrolled at an Australian trauma centre between October 2016 and October 2018. Bland-Altman limits of agreement (LOA) between paired blood gas samples taken ResultsDuring the study period 176 major trauma patients had valid paired blood gas samples available for analysis. The median time difference between paired measurements was 11 min (IQR 6–17). There was a predominance of men (81.8%) and blunt trauma (92.0%). Median Injury Severity Score was 13 (range 1–75) and inpatient mortality was 6.3%. Mean difference (ABG−VBG) and LOA between paired arterial and venous measurements were 0.036 (LOA −0.048 to 0.120) for pH, −1.27 mmol/L (LOA −4.35 to 1.81) for BD, −0.64 mmol/L (LOA −1.86 to 0.57) for lactate and −1.97 mmol/L (LOA −5.49 to 1.55) for bicarbonate. Independent assessment of the VBG ‘false negative’ cases (n=20) suggested an ABG would change circulatory management in two cases.ConclusionsIn trauma patients VBG and ABG parameters displayed suboptimal agreement. However, in cases flagged as VBG ‘false negative’ independent review indicated that the availability of an ABG was unlikely to change management.

PURPOSE To analyze the agreement of corrected intraocular pressure (IOP) values between Corvis ST (ΔIOP1) and Pentacam (ΔIOP2) in patients with keratoconus (KC), subclinical KC (sub-KC), and normal cornea. METHODS In total, 235 eyes were divided into KC, sub-KC, and control groups. Differences in ΔIOP1 (biomechanically corrected IOP minus uncorrected IOP) and ΔIOP2 (central corneal thickness-corrected amounts of IOP) were analyzed within and among groups. Topographical and biomechanical differences were compared among the 3 groups. Factors affecting differences between ΔIOP1 and ΔIOP2 were analyzed. Agreement analysis of ΔIOP2 and ΔIOP1 was performed by Bland-Altman plots for all 3 groups. RESULTS Mean ΔIOP1 was highest in the KC group (1.23 ± 0.84 mm Hg), followed by sub-KC and control groups (all P < 0.05). Deformation amplitude ratio at 2 mm (DA-2 mm), integrated radius, stiffness parameter at first applanation, and Corvis biomechanical index values significantly differed between sub-KC and control groups. The differences between ΔIOP1 and ΔIOP2 were affected by stiffness parameter at first applanation, after adjusting for central corneal thickness and age, in all 3 groups. The lowest agreement between ΔIOP2 and ΔIOP1 was observed in the KC group (mean difference: 1.90 mm Hg; 95% limit of agreement ranged from -0.2 to 3.9 mm Hg). CONCLUSIONS Among the 3 groups in this study, the KC group exhibited the worst consistency between ΔIOP2 and ΔIOP1. For the sub-KC and control groups, corrected IOP values derived by Pentacam were similar to Corvis ST. Ophthalmologists should carefully consider the mechanical properties of eyes with KC during IOP management.

BACKGROUND: This study assessed the measurement properties of two commonly used self-report physical activity (PA) measures: the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and the Physical Activity Scale for the elderly (PASE) in adults with osteoarthritis. METHODS: Secondary analysis of the MOSAICS cluster randomised controlled trial baseline and 3-month follow-up questionnaires, total scores and subdomains of the IPAQ-SF and PASE were compared. Intra-class correlations (ICC) were used to assess test-retest reliability, measurement error was assessed using standard error of measurement (SEM), smallest detectable change (SDC) and 95% limits of agreement (LoA). Responsiveness was assessed using effect size (ES), standard responsive measurement (SRM) and response ratio (RR). RESULTS: There was moderate correlation (r = 0.56) between the total IPAQ-SF scores (score ranges 0-16,398) and the total PASE scores (score ranges 0-400). Subdomain correlations were also moderate (ranges 0.39-0.57). The PASE showed greater reliability compared to the IPAQ-SF (ICC = 0.68; 0.61-0.74 95% CI and ICC = 0.64; 0.55-0.72, respectively). Measurement errors in both measures were large: PASE SEM = 46.7, SDC = 129.6 and 95% LoA ranges = -117 to 136, the IPAQ-SF SEM = 3532.2 METS-1 min-1 week , SDC = 9790.8 and 95% LoA ranges = -5222 to 5597. Responsiveness was poor: ES -0.14 and -0.16, SRM -0.21 and -0.21, and RR 0.12 and 0.09 for the IPAQ-SF and PASE, respectively. DISCUSSION: The IPAQ-SF and PASE appear limited in reliability, measurement error and responsiveness. Researchers and clinicians should be aware of these limitations, particularly when comparing different levels of PA and monitoring PA levels changes over time in those with osteoarthritis.

This study aimed to evaluate the agreement and reliability of the Feline Grimace Scale (FGS) among cat owners, veterinarians, veterinary students and nurses/technicians. Raters (n = 5/group) scored 100 images using the FGS (ear position, orbital tightening, muzzle tension, whiskers position and head position). Intra-class correlation coefficients (ICC) were used to assess inter- and intra-rater reliability. Agreement between each group and the veterinarian group (gold-standard) was calculated using the Bland–Altman method. Effects of gender, age and number of cats owned on FGS scores were assessed using linear mixed models. Inter-rater reliability was good for FGS final scores (ICC > 0.8). The muzzle and whiskers yielded lower reliability (ICC = 0.39 to 0.74). Intra-rater reliability was excellent for students and veterinarians (ICC = 0.91), and good for owners and nurses (ICC = 0.87 and 0.81, respectively). A very good agreement between all groups and veterinarians (bias p = 0.006); however, male raters were underrepresented in this study. Scores were not affected by age or number of cats owned. The FGS is reliable for feline acute pain assessment when used by individuals with different experience.

Clinical relevance: Accuracy of tonometers is of vital importance in the detection and treatment of glaucoma.Background: This study investigates: agreement in intraocular pressure measurements between three tonometers and Goldmann applanation tonometry (GAT); inter-optometrist agreement for each tonometer; intra-optometrist agreement for GAT; association between central corneal thickness (CCT) and IOP measurements with each tonometer.Methods: IOP was measured using: CT-1P Non-Contact Tonometer (NCT) (Topcon Corporation, Tokyo, Japan), Pulsair IntelliPuff (Keeler Ltd., Windsor, UK) and Icare rebound tonometer (Icare, Helsinki, Finland) by two optometrists in a random order. Two GAT readings were obtained by each optometrist in a randomised masked manner. Mean differences, and 95% limits of agreement (LoA) for each measurement were calculated. CCT was measured by CT-1P pachymeter.Results: Forty-one participants' IOPs were measured. Mean differences (95% LoA) between NCT, Pulsair, Icare compared to GAT for one optometrist were: 0.8 (-5.4 to 6.9) mmHg, -1.7 (-8.2 to 4.8) mmHg, -1.6 (-9.0 to 5.9) mmHg. Mean differences (95% LoA) in inter-optometrist agreement for GAT, NCT, Pulsair and Icare were: 0.3 (-6.7 to 7.3) mmHg, 0.4 (-2.1 to 2.9) mmHg, -0.9 (-3.6 to 1.9) mmHg and -0.2 (-4.9 to 4.5) mmHg, respectively. Mean differences (95% LoA) for intra-optometrist agreement for GAT were 0.2 (4.3 to -4.7) mmHg and 0.1 (3.6 to -3.9) mmHg for each optometrist, respectively. There was a weak positive association between CCT and both GAT (r2 = 0.11) and NCT (r2 = 0.12).Conclusion: Pulsair and Icare may measure IOP lower than GAT. Mean differences for inter-optometrist agreement for all tonometers were < 1 mmHg; Pulsair showed a statistically significant difference. Intra-optometrist agreement for GAT was good. IOP measurements taken by two community optometrists are comparable using tonometers used in community practice.

Objectives: VO2max is globally considered as the gold standard to evaluate the cardiorespiratory fitness that is an essential component to judge one’s aerobic fitness level. The present study was aimed to enumerate the validity for application of Cooper’s 12 min run test (CRT) in predicting VO2max among Indian swimmers and volleyball players. Materials and Methods: Swimmers (male = 66, female = 70) and volleyball players (male = 88, female = 81) were recruited by simple random sampling from reputed clubs of Kolkata. They were segregated into study and confirmatory groups. VO2max was determined by graded incremental cycle ergometer test followed by expired gas analysis and indirect CRT method. Results: Predicted VO2max (PVO2max) showed significant difference with the directly measured VO2max (VO2max) in study groups of both sports. Limits of agreement between PVO2max and VO2max proved inapplicability of current CRT protocol in studied populations. Modified population specific equations were computed from significant correlation of VO2max with distance covered in Cooper run test. Application of these norms in confirmatory groups revealed insignificant difference between PVO2max and VO2max in both genders. Conclusion: Modified equations are validated for application of CRT in evaluating VO2max in swimmers and volleyball players of both genders of Kolkata, India.

Clinical relevance: Refracting low vision patients require special procedures and strategies. A device-taking the reduced visual acuity and higher blur tolerance into account-is designed to measure refraction in this group.Background: Instant Vision Assessment Device (IVAD) is a stenopaeic slit refraction system in a binocular telescopic optometer calibrated to measure refraction. This study aims to validate IVAD in measuring refraction of low vision patients.Methods: Refractions were measured with IVAD on the right eyes of 35 normal subjects (ages nine to 69) and on the better eyes of 20 low vision subjects (ages 60 to 90) and compared with subjective refraction (SR). The visual acuities were compared in the low vision group. Paired Student t-test and Bland-Altman analysis were used to test the significance of difference and limits of agreement between methods, respectively.Results: In normal subjects, mean spherical equivalent refraction (M) measured by IVAD and SR was -2.88 ± 2.51 D and -2.72 ± 2.29 D, respectively, and the difference of -0.16 ± 0.47 D was not statistically significant (p = 0.05, t = 2.03). In low vision subjects, M measured by IVAD and SR was-0.66 ± 2.64 D and -0.55 ± 2.61 D, respectively, and the difference of -0.11 ± 0.59 D was also not statistically significant (p = 0.43, t = 2.09). Only the astigmatism J0 in the normal subject group of -0.03 ± 0.24 D by IVAD and 0.07 ± 0.17 D by SR showed a statistically significant difference of -0.10 ± 0.25 D (p = 0.04, t = 2.03). In low vision subjects, mean visual acuities with refraction from IVAD and SR were 0.52 ± 0.32 logMAR and 0.53 ± 0.32 logMAR, respectively, and the difference of 0.01 ± 0.07 logMAR was not statistically significant (p = 0.51, t = 2.09). At least 80% of the IVAD measure of refraction components (M, J0, J45) were within ±0.50 D of SR measure.Conclusion: IVAD is a practical and valid refraction method for low vision patients.

To evaluate the reliability and agreement between Fully Refocused Steady-State magnetic resonance sequences (FRSS) and the IOLMaster® 500 optical biometer for measuring anterior chamber depth (ACD) and axial length (AL). In a sample of 32 healthy volunteers, separate observers measured the ACD and AL of both eyes using both techniques (inter-method) and through repeated FRSS measurements (interobserver) and by the same observer (intraobserver). We employed the Bland–Altman method to determine the agreement between FRSS and partial coherence interferometry (using the IOLMaster®) and the interobserver and intraobserver variability, providing the limits of agreement (LoA, or mean difference ± 1.96 SD). Correlation coefficients and intraclass correlation coefficients were also provided. For ACD measurements with FRSS in pseudo-color scale, we obtained an LoA of 0.016 ± 0.266 mm compared with partial coherence interferometry. For AL with FRSS in greyscale, the LoA was 0.019 ± 0.383 mm. Maximum interobserver variability showed a − 0.036 ± 0.247 mm LoA for ACD with FRSS in pseudo-color scale. Maximum intraobserver variability was 0.000 ± 0.157 mm LoA for AL with FRSS in greyscale. ACD and AL measurements using FRSS sequencing present high LoA and reliability when compared with partial coherence interferometry using the IOLMaster® 500. The results were better for FRSS in pseudo-color scale in ACD determination and for FRSS in greyscale in AL determination. FRSS would not be recommended for IOL power calculation due to variability of AL measurement.

Collecting real-world evidence via ‘at home’ assessments in ambulatory patients or healthy volunteers is becoming increasingly important, both for research purposes and in clinical practice. However, given the mobile technology that is frequently used for these assessments, concise assessments are preferred. The current study compared single-item ratings with multiple-item subscale scores of the same construct, by calculating the corresponding Bland and Altman 95% limits of agreement interval. The analysis showed that single-item ratings are usually in good agreement with assessments of their corresponding subscale. In the case of more complex multimodal constructs, single-item assessments were much less often in agreement with multiple-item questionnaire outcomes. The use of single-item assessments is advocated as they more often incorporate assessments of all aspects of a certain construct (including the presence, severity, and impact of the construct under investigation) compared to composite symptom scores.

Context: An accurate assessment of lumbar spine active range of motion (AROM) is clinically important. Dual inclinometry is recommended as the optimal technique for measuring lumbar flexion AROM; however, the procedures differ in the literature. Objective: To compare 2 different handheld digital dual inclinometry (HDDI) techniques for evaluating lumbar flexion AROM. Design: The study was a repeated-measures design consisting of 2 trials. Setting: Laboratory. Participants: A sample of 69 adult volunteers (28 men and 41 women; mean age 23.8 [2.4] y) without pain or injury to their back, hips, or abdomen for at least 3 months participated in the study. Intervention: Using standardized methods, 1 trained tester performed 2 different HDDI measurements of standing lumbar flexion AROM on each subject. Each subject performed one repetition of AROM lumbar flexion per HDDI measurement. The HDDI measures differed in the process for placing the upper inclinometer, with one technique identifying the upper landmark by skilled palpation of the T12 spinous process and the other technique by measuring 15-cm cephalad to the S2 region landmark to approximate the location of the T12 spinous process. Main Outcome Measures: A dependent t test, Pearson correlation coefficient (r), the 95% limits of agreement, and Bland–Altman plots were used to examine agreement between the techniques. Results: Dependent t testing showed no significant differences between the techniques (mean difference = 1.2°, P = .11). A strong correlation existed between the 2 HDDI techniques (r = .80, P Conclusions: The findings suggest that HDDI measurements of lumbar flexion AROM are comparable when using either of the 2 HDDI techniques described. Clinicians can make an evidence-based choice for using either method of measuring lumbar flexion AROM.

Objectives To establish agreement between self-reported and actigraphy-based total sleep time (TST). To determine the impact of self-reported sleep problems on these measurements. Design Cross-sectional study using data from Wave 3 of The Irish Longitudinal Study on Ageing (2014–2015). Participants Community-dwelling older adults, aged ≥50 years, with self-reported sleep information and ≥4 days of actigraphy-based TST (n = 1520). Measurement Self-reported total sleep time, daytime sleepiness, insomnia symptoms (trouble falling asleep, trouble waking too early) measured during a structured self-interview. Actigraphy-based total TST was collected using GENEactiv wrist-worn accelerometers. Demographic characteristics and health information were controlled for. Analyses included descriptive statistics, reliability and agreement analysis using paired t-tests, intra-class correlations and Bland-Altman analysis. Linear regression was used to model associations with measurement discrepancies. Results Participants reported that they slept 7.0 hours (SD: 1.4, Range: 2.0–13.0 hours) on average, compared to 7.7 hours (SD: 1.2 hours, Range: 3.0–13.0 hours) recorded by accelerometry. Trouble falling asleep or waking too early “most of the time” were associated with under-reporting of sleep by 2.3, and 2.2 hours respectively. Agreement between measurements had an intra-class correlation of 0.18 and wide 95% limits of agreement (-3.90 to 2.55 hours). Under-reporting of sleep was independently associated with insomnia symptoms. Conclusion The agreement between self-reported and actigraphy-based TST in community dwelling older adults was low. Self-reported insomnia symptoms were independently associated with under-reporting of sleep. Studies seeking to measure sleep duration should consider inclusion of questions measuring experience of insomnia symptoms to account for potential influence on measurements.

Although virtual non-contrast (VNC) successfully removes iodinated contrast, uncertainty exists regarding the feasibility of VNC to suppress iodine for detecting thyroid calcification. Therefore, we evaluated whether both intrinsic and extrinsic iodine attenuation were suppressed on VNC images. We enrolled 128 patients (male: female 17:111; age 48.0 ± 10.4 years) who underwent dual-layer dual-energy CT (DL-DECT) examination before their thyroid cancer surgeries. Two additional sets of VNC (VNCu, VNCc) images were retrospectively generated from their true unenhanced (TUE) and true contrast-enhanced (TCE) series. We compared CT attenuation values measured on the VNCu and VNCc images by drawing identical regions of interest encompassing thyroid parenchyma, then subjectively determined the concordance of calcification. Although CT attenuation discrepancies between the VNCu and VNCc were significant (2.0 ± 5.7HU, p

Left ventricular longitudinal strain (LVLS) performed using subcostal windows is a novel alternative for patients who require strain imaging but have poor apical windows. We investigated the reproducibility and inter-vendor variability of subcostal LVLS. One hundred and twenty-four echocardiographic studies were analysed from 73 women with early stage HER2-positive breast cancer. Speckle tracking strain was performed offline using EchoPAC and TomTec on subcostal 4-chamber and 3-chamber views to obtain subcostal 4-chamber (SC4_LS) and 3-chamber (SC3_LS) LVLS which was then averaged (SCav_LS). Reproducibility of subcostal single chamber and averaged LVLS were assessed. Measurements between platforms were compared. Strain was reported in absolute magnitude. EchoPAC measurements of SC3_LS (20.5 ± 2.4% vs. 21.2 ± 2.5%, p = 0.002) and SCav_LS (20.9 ± 2.1% vs. 21.2 ± 2.1%, p = 0.02) were lower than TomTec measurements while SC4_LS was similar (21.3 ± 2.7% vs. 21.3 ± 2.5%, p = 0.94). Mean differences between EchoPAC and TomTec were ≤ 0.6% strain units for all subcostal LVLS measurements; SCav_LS showed the narrowest limits of agreement (LOA) (mean difference − 0.3%, LOA − 3.2 to 2.6%). EchoPAC and TomTec measurements of SCav_LS showed good correlation (r = 0.76, p

To assess the feasibility of a CNN-based liver registration algorithm to generate difference maps for visual display of spatiotemporal changes in liver PDFF, without needing manual annotations. This retrospective exploratory study included 25 patients with suspected or confirmed NAFLD, who underwent PDFF-MRI at two time points at our institution. PDFF difference maps were generated by applying a CNN-based liver registration algorithm, then subtracting follow-up from baseline PDFF maps. The difference maps were post-processed by smoothing (5 cm2 round kernel) and applying a categorical color scale. Two fellowship-trained abdominal radiologists and one radiology resident independently reviewed difference maps to visually determine segmental PDFF change. Their visual assessment was compared with manual ROI-based measurements of each Couinaud segment and whole liver PDFF using intraclass correlation (ICC) and Bland-Altman analysis. Inter-reader agreement for visual assessment was calculated (ICC). The mean patient age was 49 years (12 males). Baseline and follow-up PDFF ranged from 2.0 to 35.3% and 3.5 to 32.0%, respectively. PDFF changes ranged from - 20.4 to 14.1%. ICCs against the manual reference exceeded 0.95 for each reader, except for segment 2 (2 readers ICC = 0.86–0.91) and segment 4a (reader 3 ICC = 0.94). Bland-Altman limits of agreement were within 5% across all three readers. Inter-reader agreement for visually assessed PDFF change (whole liver and segmental) was excellent (ICCs > 0.96), except for segment 2 (ICC = 0.93). Visual assessment of liver segmental PDFF changes using a CNN-generated difference map strongly agreed with manual estimates performed by an expert reader and yielded high inter-reader agreement. • Visual assessment of longitudinal changes in quantitative liver MRI can be performed using a CNN-generated difference map and yields strong agreement with manual estimates performed by expert readers.

Background There are currently no validated methods for energy intake assessment in adolescents with intellectual and developmental disabilities (IDD). The purpose of this study was to determine the feasibility of collecting 3-day image-assisted food records (IARs) and doubly labelled water (TDEEDLW ) data in adolescents with IDD and to obtain preliminary estimates of validity and reliability for energy intake estimated by IAR. Methods Adolescents with IDD completed a 14-day assessment of mean daily energy expenditure using doubly labelled water. Participants were asked to complete 3-day IARs twice during the 14-day period. To complete the IAR, participants were asked to fill out a hard copy food record over three consecutive days (two weekdays/one weekend day) and to take before and after digital images of all foods and beverages consumed using an iPad tablet provided by the study. Energy intake from the IAR was calculated using Nutrition Data System for Research. Mean differences, intraclass correlations and Bland-Altman limits of agreement were performed. Results Nineteen adolescents with IDD, mean age 15.1 years, n = 6 (31.6%) female and n = 6 (31.6%) ethnic/racial minorities, enrolled in the trial. Participants successfully completed their 3-day food records and self-collected doubly labelled water urine samples for 100% of required days. Images were captured for 67.4 ± 30.1% of all meals recorded at assessment 1 and 72.3 ± 29.5% at assessment 2. The energy intake measured by IAR demonstrated acceptable test-retest reliability (intraclass correlation = 0.70). On average, IAR underestimated total energy intake by -299 ± 633 kcal/day (mean per cent error = -9.6 ± 22.2%); however, there was a large amount of individual variability in differences between the IAR and TDEEDLW (range = -1703 to 430). Conclusions The collection of IAR and TDEEDLW is feasible in adolescents with IDD. While future validation studies are needed, the preliminary estimates obtained by this study suggest that in adolescents with IDD, the IAR method has acceptable reliability and may underestimate energy intake by ~9%.

The Language ENvironment Analysis system (LENA) records children’s language environment and provides an automatic estimate of adult–child conversational turn count (CTC). The present study compares LENA’s CTC estimate to manually coded CTC on a sample of 70 English‐speaking infants recorded longitudinally at 6, 10, 14, 18, and 24 months of age. At each age, LENA’s CTC was significantly higher than manually coded CTC (all ps

Icare tonometer overestimated intraocular pressure (IOP) as compared with Perkins and this variation was higher in IOP19 mm Hg and corneal opacity in patients with pediatric glaucoma.To compare the IOP measured by Icare ic200 with Perkins tonometer in pediatric glaucoma with different corneal characteristics.Patients of pediatric glaucoma posted for routine examination under anesthesia, age below 12 years were enrolled. All patients underwent IOP measurement with Perkins and Icare ic200 tonometer by the same observer. Basic demographic data and other relevant clinical data were recorded. Central corneal thickness (CCT), horizontal corneal diameter, and corneal characteristics such as cornea clarity was recorded.A total of 194 eyes of 105 patients were analyzed. The difference between Perkins and Icare IOP was -0.816 mm Hg with the Bland-Altman plot 95% limits of agreement (LoA) from -11.194 to 9.562 mm Hg and 5.1% (10) values lying outside LoA. At IOP19 mm Hg, the difference was -0.65 mm Hg and IOP ≥19 mm Hg, the difference was higher, -1.12 mm Hg. In the clear cornea group (123 eyes), the difference in IOP by 2 tonometers was -0.776 mm Hg with the Bland-Altman plot 95% LoA between -10.679 and 9.128 mm Hg. In hazy corneas (36 eyes), the difference in IOP was 0.531 mm Hg. The Bland-Altman plot showed 95% LoA between -6.242 and 7.303 mm Hg. In the scarred cornea group (35 eyes), the difference in IOP between the 2 was -2.343 mm Hg and the Bland-Altman plot showed wide 95% LoA from -16.302 to 11.616 mm Hg.Icare tonometer overestimated IOP as compared with Perkins and this variation was higher in eyes with IOP≥19 mm Hg, CCT615 μm, and scarred corneas. A moderate correlation between IOP and CCT for both tonometers was noted.

Left atrial strain (LAS) on transthoracic echocardiogram (TTE) is increasingly recognised to have clinical utility in cardiovascular disease. Differences in LAS measurements between vendors remains a barrier for clinical use. We sought to compare LAS between two commonly used software platforms; the layer-specific endocardial and mid-myocardial measurements of LAS on General Electric (GE) Echopac were compared to TomTec strain. LAS was measured in 88 individuals with no previous cardiac history and 40 paroxysmal AF (PAF) patients, in sinus rhythm at TTE. Conventionally, LAS measured using GE Echopac is mid-myocardial strain (GE-mid); additionally, endocardial (GE-endo) LAS was evaluated. Both LAS measurements by GE were compared to TomTec-Arena (v2.30.02) measurements. Reservoir (ƐR), contractile (ƐCT) and conduit (ƐCD) phasic strain were evaluated. Both GE-mid and GE-endo LAS correlated well with TomTec LAS. On Bland–Altman analysis, GE-mid LAS measurements were systematically lower than TomTec LAS (ƐR: mean difference (MD) − 6.08%, limits of agreement (LOA) − 12%, 0%, ƐCT: MD − 0.8%, LOA − 7%, 5%, ƐCD: MD − 5.2% LOA − 12%, 1%). GE-endo LAS demonstrated no systematic difference from TomTec LAS, but had wider limits of agreement (ƐR: MD 0.41%, LOA − 7%, 8%, ƐCT: MD 0.50%, LOA − 6%, 7%, ƐCD: MD − 0.08%, LOA − 7%, 7%). ƐR had the best reproducibility. Mid-myocardial LAS, routinely evaluated by GE Echopac software, systematically underestimates LAS compared to TomTec. Using GE endocardial LAS eliminated this bias, but introduced greater variation between measurements. Serial measurements of LAS should therefore be performed on the same vendor system.

PurposeA new amblyopia tracker app has been designed to provide parents with a method of monitoring a child's vision by presenting a single optotype size that the tester moves to identify the furthest distance the optotypes can be seen. The aim of this study is to evaluate this methodology in adults, comparing the findings to visual acuity (VA) measured with the iSight app and to determine the test retest variability.MethodsAdults, aged 18-39 years, with no known eye condition and VA ≤ 0.7 logMAR were recruited. Bangerter filters were used to simulate amblyopia, where VA was reduced below 0.0 with an interocular difference of at least 0.2 logMAR. Testing for both apps was performed monocularly, with the test order being randomised.ResultsData from 32 subjects were analysed. For the test retest variability analysis, paired t-tests showed no statistically significant difference between the tests for either eye, either app or the interocular acuity difference (p > 0.3 in all cases). Bland Altman plots showed similar limits of agreement between the two apps. When comparing measurements between the apps there was no statistically significant difference on the first or second test, either eye or the interocular acuity difference (p > 0.5 in all cases).ConclusionThe results support the theory that changing distance is a valid method of assessing VA as the measurements agree well with the standard approach of reducing optotype size. Test retest variability is similar between the two apps and there is good agreement between the measurements.

Background: Cardiac output determination is essential in precapillary pulmonary hypertension. While direct Fick is the gold standard, thermodilution is commonly used as the reference method. Moving to noninvasive methods would be highly beneficial for patients, avoiding repetitive invasive assessments. This systematic review followed 3 objectives: (1) assessing the validity of indirect Fick and thermodilution in precapillary pulmonary hypertension, (2) assessing the interchangeability of noninvasive cardiac output measurement methods against reference methods in precapillary pulmonary hypertension, and (3) detecting methodological heterogeneity in the included studies. Methods: We systematically reviewed the literature using medical databases and following PRISMA guidelines. We included articles comparing an invasive or noninvasive cardiac output measurement method with thermodilution or direct Fick in precapillary pulmonary hypertension patients. Cutoffs of limits of agreement and percentage error derived from the Bland and Altman graph were used to accept interchangeability. To study methodological heterogeneity, we extracted 9 quality criteria from all studies. Results: Eleven studies were included. None reached the suggested interchangeability criteria. The median number of the 9 assessed quality criteria was 2 with interquartile range (0–4). Conclusions: Further studies evaluating the reliability of thermodilution and the consequences of its use in precapillary pulmonary hypertension patients are necessary. No evidence supports the use of indirect Fick in precapillary pulmonary hypertension. The studied noninvasive methods could not be considered interchangeable with invasive methods. A robust methodology should be used to draw sensible conclusions.