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Abstract Background The evaluation of inter-rater reliability (IRR) is integral to research designs involving the assessment of observational ratings by two raters. However, existing literature is often heterogeneous in reporting statistical procedures and the evaluation of IRR, although such information can impact subsequent hypothesis testing analyses. Methods This paper evaluates a recent publication by Chen et al., featured in BMC Nephrology, aiming to introduce an alternative statistical approach to assessing IRR and discuss its statistical properties. The study underscores the crucial need for selecting appropriate Kappa statistics, emphasizing the accurate computation, interpretation, and reporting of commonly used IRR statistics between two raters. Results The Cohen’s Kappa statistic is typically used for two raters dealing with two categories or for unordered categorical variables having three or more categories. On the other hand, when assessing the concordance between two raters for ordered categorical variables with three or more categories, the commonly employed measure is the weighted Kappa. Conclusion Chen and colleagues might have underestimated the agreement between AU5800 and UN2000. Although the statistical approach adopted in Chen et al.’s research did not alter their findings, it is important to underscore the importance of researchers being discerning in their choice of statistical techniques to address their specific research inquiries.

The spatial assessment criteria system for hybridizing renewable energy sources, such as hybrid solar-wind farms, is critical in selecting ideal installation sites that maximize benefits, reduce costs, protect the environment, and serve the community. However, a systematic approach to designing indicator systems is rarely used in relevant site selection studies. Therefore, the current paper attempts to present an inclusive framework based on content validity to create an effective criteria system for siting wind-solar plants. To this end, the criteria considered in the related literature are captured, and the top 10 frequent indicators are identified. The Delphi technique is used to subject commonly used factors to expert judgments. Other factors are considered according to expert recommendations. In this context, the assessment tool was a combination of questionnaires and interviews with experts from scientific backgrounds that reflect the measurement target. The item-level content validity index (I-CVI) is applied along with the modified Kappa statistic (k*) to analyze expert ratings and suggestions. The results demonstrate the superiority of 9 and 4 commonly used factors and the suggested factors, respectively. The 13 criteria have achieved high agreement among experts at I-CVIs ≥ 0.78 and k*s > 0.76. The conclusion can be drawn that the modified Kappa statistic used in this analysis has a more significant effect on eliminating irrelevant factors. The current methodology and consequences might pave the way for making informed decisions to locate wind and solar farms. [ABSTRACT FROM AUTHOR]

Abstract Background In research designs that rely on observational ratings provided by two raters, assessing inter-rater reliability (IRR) is a frequently required task. However, some studies fall short in properly utilizing statistical procedures, omitting essential information necessary for interpreting their findings, or inadequately addressing the impact of IRR on subsequent analyses’ statistical power for hypothesis testing. Methods This article delves into the recent publication by Liu et al. in BMC Cancer, analyzing the controversy surrounding the Kappa statistic and methodological issues concerning the assessment of IRR. The primary focus is on the appropriate selection of Kappa statistics, as well as the computation, interpretation, and reporting of two frequently used IRR statistics when there are two raters involved. Results The Cohen’s Kappa statistic is typically utilized to assess the level of agreement between two raters when there are two categories or for unordered categorical variables with three or more categories. On the other hand, when it comes to evaluating the degree of agreement between two raters for ordered categorical variables comprising three or more categories, the weighted Kappa is a widely used measure. Conclusion Despite not substantially affecting the findings of Liu et al.?s study, the statistical dispute underscores the significance of employing suitable statistical methods. Rigorous and accurate statistical results are crucial for producing trustworthy research.

Background: In research designs that rely on observational ratings provided by two raters, assessing inter-rater reliability (IRR) is a frequently required task. However, some studies fall short in properly utilizing statistical procedures, omitting essential information necessary for interpreting their findings, or inadequately addressing the impact of IRR on subsequent analyses' statistical power for hypothesis testing. Methods: This article delves into the recent publication by Liu et al. in BMC Cancer, analyzing the controversy surrounding the Kappa statistic and methodological issues concerning the assessment of IRR. The primary focus is on the appropriate selection of Kappa statistics, as well as the computation, interpretation, and reporting of two frequently used IRR statistics when there are two raters involved. Results: The Cohen's Kappa statistic is typically utilized to assess the level of agreement between two raters when there are two categories or for unordered categorical variables with three or more categories. On the other hand, when it comes to evaluating the degree of agreement between two raters for ordered categorical variables comprising three or more categories, the weighted Kappa is a widely used measure. Conclusion: Despite not substantially affecting the findings of Liu et al.?s study, the statistical dispute underscores the significance of employing suitable statistical methods. Rigorous and accurate statistical results are crucial for producing trustworthy research. [ABSTRACT FROM AUTHOR]

ABSTRACTThe aim of this study was to assess whether there was agreement between self-reported data in a survey and medical records regarding diagnoses and symptoms at COVID-19 onset. The impact of sociodemographic factors on agreement between the two data sources was also assessed. Cross-sectional data were extracted from a Swedish longitudinal cohort study. In total, 401 non-hospitalized patients with a polymerase chain reaction-confirmed COVID-19 infection responded to a survey and agreed to a review of their electronic medical records. Agreement, estimated using the kappa statistic, sensitivity, and specificity were calculated for nine diagnoses and eleven symptoms. Differences between subgroups based on sociodemographic factors were assessed. The agreement between the self-reported data and medical records was at a substantial to moderate level for diagnoses such as diabetes mellitus (kappa 0.65, sensitivity 86%) and hypertension (kappa 0.59, sensitivity 56%) and at a fair level for more difficult-to-define conditions such as ongoing immunosuppressive treatment (kappa 0.27, sensitivity 25%). The agreement between the two data sources on symptoms was between fair and poor (kappa 0.36 for fever; kappa 0.05 for fatigue). Agreement for some diagnoses and symptoms varied across some sociodemographic subgroups, e.g. agreement in diabetes mellitus was significantly better in males (kappa 1.0) than females (kappa 0.52, homogeneity tests p = 0.02). In general, kappa values were lower for symptoms than diagnoses. The agreement between the two sources varied with diagnoses and symptoms and was also influenced by sociodemographic factors. This study illustrates that it is important to consider type of data used in the epidemiological studies as different information sources differ with quality and accuracy.

Predictive modeling and land use/land cover change studies in complex systems are well advanced. Cellular automata (CA)-Markov chain (MC) can be defined as one frequently preferred method for this purpose. This paper aims to adapt the CA-MC model to the simulation of residential areas in the city. The proposed method was tested in the city center of Kastamonu, Türkiye, using four time periods: 1985, 2011, 2015, and 2021. Spatio-temporal change maps were produced using ArcGIS 10.0 software. Land use simulation of the urban center, including residence units for 2031 and 2057, was performed using the integrated CA-MC technique. The method's suitability was demonstrated with the Kappa index of agreement values (Kstandart: 0.93; Klocation: 0.98; Kno: 0.98; and KlocationStrata: 0.95). Within the scope of the study, two different scenarios were designed as short term (S1) and long term (S2). According to the predictions for 2031, there was a residential area increase of 15% in S1 and 29% in S2. When we reach 2057, these growth values were measured as 50% according to S1 and 72% according to S2. [ABSTRACT FROM AUTHOR]

Land use and land cover transition is continue process due to various anthropogenic activities and altering the landscape pattern of the metropolitan area of Lahore over the last two decade. LULC has been emerging masses of environmental problems including land use issues for the inhabitants, city planners, and managers. This research has been focused on the LULC change from 1998 to 2018 and their impact to forecast the landscape pattern of 2023 and 2028 in metropolitan area of Lahore. Numerous satellite imageries including land sat 5 TM and landsat 8 OLI has been undergone by supervised classification for the preparation of LULC map, land change moderler MCL to calculate the transition in LULC and CA-Markov model for predicting upcoming transitions. Results have validated by transition matrix, Google Earth data and kappa statistics. Derived results has depicted the decreased in water bodies 2.70% to 0.60%, vegetation 24.90% to 22.60% and barren land 42.50% to 35.70% and increased in built up area 29.80 % to 41% between 1998 to 2018. Finding clearly represents the loss of ecological and barren landscape over the last two decade and therefore urban expansion will likely to continue the change in landscape. This study will provide a baseline reference to urban planners and policymakers to make informed decision for management of land resources, urban land planning and for maintain sustainable land development.

Introduction: Automated blood pressure (BP) monitor is widely used to assess the blood pressure (BP) of the study subjects in community-based researches. This study aims at the detection of hypertension by automated BP device and examines the concordance and validity between automated and mercury-free LED BP devices. Materials and Methods: This cross-sectional study was conducted in the tribal state of Jharkhand in India from January 2017 to June 2017. A total of 300 study participants aged more than 18 years were enrolled in this study. BP of the patients in the sitting position was measured three times each by automated device and mercury-free LED BP device. The different sets of readings were assessed by concordance correlation coefficient (CCC) and other validity measures. Results: The CCC for systolic and diastolic BP measured by automated and mercury-free LED BP is 0.88 and 0.85, respectively. The mean difference between systolic and diastolic BP by both the instruments is statistically insignificant (P > 0.05). The sensitivity, specificity, PPV, NPV, and accuracy of automated BP devices to predict hypertension is 96.61%, 92.21%, 75%, 99%, and 93%. The area under ROC for systolic and diastolic BP is 0.984 and 0.97, respectively with P values < 0.0001 in both the cases. Conclusions: This study concluded that the overall automated BP machine has fair degree of agreement (CCC) with a manual BP device. The validity of this monitor to screen hypertension may also be considered in field settings.

Objectives. This is a diagnostic test research study to evaluate the various existing methods of thyroid examination and their comparison with the novel modified Rose method. It also aims to measure inter-examiner variation in clinical findings based on the level of education and training, as compared to ultrasonography. Methodology. This cross-sectional study was conducted at a tertiary care hospital with eighty-three patients presenting to surgery OPD with neck swelling. Each patient was examined by one trained Junior Resident and a Surgery Consultant with all the four methods and with ultrasonography. Data was analysed by Stata-14, agreement between the two categorical variables was assessed by Kappa. In case of continuous variable agreement was assessed by Intra class correlation and Bland-Altman plot. Results. Modified Rose method by the consultant has the highest sensitivity (98%) and diagnostic odds (210) as compared to others but its specificity ranges from 46.7- 91.1% to diagnose retro-sternal extension of a goiter. It has 93.98% agreement for identification of nodules. It has a high specificity (Consultant -100%, Resident – 95.5%) with relatively lower sensitivity (Consultant -94%, Resident – 86.8%) to diagnose solitary thyroid nodule (STN) but the sensitivity and specificity for diagnosing a multinodular goitre (MNG) was high. However, the highest sensitivity to diagnose STN was highest with Crile’s method, but specificity was low. Lahey’s method was a better clinical method to palpate lymph nodes compared to the other three. Conclusion. Examination in modified Rose’s position is a better method of clinical examination of thyroid especially in patients with occult substernal extension. Lahey’s method is a better method to examine cervical lymph nodes.

Purpose: The present study was aimed to evaluate the agreement on grading normal clivus on MRI among radiologists. Methods: A retrospective study included patients who underwent MRI brain during January 1, 2015 to October 31, 2019. Two hundred forty-four patients who had no marrow pathology on MRI were included and divided into 8 age groups by decades. Three radiologists independently reviewed the signal intensity of clivus in mid sagittal T1-weighted image. The signal intensity was classified into three grades (Grade I-III). Fleiss’ kappa coefficients (k) were calculated to assess interrater agreement. Results: Of 244 patients, there were 123 (50.4%) males and 121 (49.6%) females. Age ranged from 1 to 79 years old. Clivus Grade II was more frequently reported (> 50%) by radiologists. The agreement (kappa) among all three radiologists on evaluation of clivus irrespective of the grading equals to 0.67 (95%CI: 0.60–0.74). In stratified analyses by the grade of clivus, the kappa values for Grade I to III and were 0.73, 0.62, and 0.69 respectively. Conclusion: Interrater agreement of MRI evaluation of normal clivus among radiologists was good. The visual grading criteria to classify the clivus is sufficient to distinguish the marrow maturation. However, the consensus reading should be made whenever normal clivus Grade II is read.

In this paper we evaluated the performance of four species distribution models: generalized linear (GLM), maximum entropy (MAXENT), random forest (RF) and support vector machines (SVM) model, using the distribution of the dragonfly Blue-tailed Green Darner Anax guttatus in the Gangetic riparian zone between Bijnor and Kanpur barrage, Uttar Pradesh, India. We used forest cover type, land use, land cover and five bioclimatic variable layers: annual mean temperature, isothermality, temperature seasonality, mean temperature of driest quarter, and precipitation seasonality to build the models. We found that the GLM generated the highest values for AUC, Kappa statistic, TSS, specificity and sensitivity, and the lowest values for omission error and commission error, while the MAXENT model generated the lowest variance in variable importance. We suggest that researchers should not rely on any single algorithm, instead, they should test performance of all available models for their species and area of interest, and choose the best one to build a species distribution model. [ABSTRACT FROM AUTHOR]

Introduction: Automated blood pressure (BP) monitor is widely used to assess the blood pressure (BP) of the study subjects in community-based researches. This study aims at the detection of hypertension by automated BP device and examines the concordance and validity between automated and mercury-free LED BP devices. Materials and Methods: This cross-sectional study was conducted in the tribal state of Jharkhand in India from January 2017 to June 2017. A total of 300 study participants aged more than 18 years were enrolled in this study. BP of the patients in the sitting position was measured three times each by automated device and mercury-free LED BP device. The different sets of readings were assessed by concordance correlation coefficient (CCC) and other validity measures. Results: The CCC for systolic and diastolic BP measured by automated and mercury-free LED BP is 0.88 and 0.85, respectively. The mean difference between systolic and diastolic BP by both the instruments is statistically insignificant (P > 0.05). The sensitivity, specificity, PPV, NPV, and accuracy of automated BP devices to predict hypertension is 96.61%, 92.21%, 75%, 99%, and 93%. The area under ROC for systolic and diastolic BP is 0.984 and 0.97, respectively with P values < 0.0001 in both the cases. Conclusions: This study concluded that the overall automated BP machine has fair degree of agreement (CCC) with a manual BP device. The validity of this monitor to screen hypertension may also be considered in field settings. [ABSTRACT FROM AUTHOR]

Crucial therapeutic decisions are based on diagnostic tests. Therefore, it is important to evaluate such tests before adopting them for routine use. Although things such as blood tests, cultures, biopsies, and radiological imaging are obvious diagnostic tests, it is not to be forgotten that specific clinical examination procedures, scoring systems based on physiological or psychological evaluation, and ratings based on questionnaires are also diagnostic tests and therefore merit similar evaluation. In the simplest scenario, a diagnostic test will give either a positive (disease likely) or negative (disease unlikely) result. Ideally, all those with the disease should be classified by a test as positive and all those without the disease as negative. Unfortunately, practically no test gives 100% accurate results. Therefore, leaving aside the economic question, the performance of diagnostic tests is evaluated on the basis of certain indices such as sensitivity, specificity, positive predictive value, and negative predictive value. Likelihood ratios combine information on specificity and sensitivity to expresses the likelihood that a given test result would occur in a subject with a disorder compared to the probability that the same result would occur in a subject without the disorder. Not all test can be categorized simply as “positive” or “negative.” Physicians are frequently exposed to test results on a numerical scale, and in such cases, judgment is required in choosing a cutoff point to distinguish normal from abnormal. Naturally, a cutoff value should provide the greatest predictive accuracy, but there is a trade-off between sensitivity and specificity here - if the cutoff is too low, it will identify most patients who have the disease (high sensitivity) but will also incorrectly identify many who do not (low specificity). A receiver operating characteristic curve plots pairs of sensitivity versus (1 − specificity) values and helps in selecting an optimum cutoff – the one lying on the “elbow” of the curve. Cohen's kappa (κ) statistic is a measure of inter-rater agreement for categorical variables. It can also be applied to assess how far two tests agree with respect to diagnostic categorization. It is generally thought to be a more robust measure than simple percent agreement calculation since kappa takes into account the agreement occurring by chance.

Introduction: In the last two decades, percentage of underweight has been not much changed while prevalence of obesity is increased by four to eight folds.(1)(2)(3) Having an incorrect perception about one’s body weight could make one unlikely to seek intervention. This study was aimed to assess nutritional status of the young girls, the agreement between the perceived and actual weight category and to identify how the socio-demographic determinants affect nutritional status and its perceptions. Methodology: This was a cross sectional study conducted between December 2013 to July 2014 among 660 young girls (15-25 years) living in the slums of Surat. Study tools were a pretested, semi-structured questionnaire, weighing machine and stadiometer. Results: Thirty two percent were under weight. 7.9% were overweight and 0.8% was obese. Correct perception about body weight was seen among 56.14%. When person agreement was done for perception and reality towards their weight, observed kappa is 0.21 with CI 0.14-0.28. This showed very poor agreement between the reality of their BMI and their perception towards their weight. Pallor was present among 44.4% participants Conclusion: Awareness drive is needed to correct their perception by about BMI, healthy body and healthy diet to prevent malnutrition.

Purpose: Laryngeal electromyography (LEMG) has been considered as gold standard in diagnostics of vocal fold movement impairment, but is still not commonly implemented in clinical routine. Since the signal interpretation of LEMG signals (LEMGs) is often a subjective and semi-quantitative matter, the goal of this study was to evaluate the inter-rater reliability of neurolaryngologists on LEMGs of volitional muscle activity. Methods: For this study, 52 representative LEMGs of 371 LEMG datasets were selected from a multicenter registry for a blinded evaluation by 7 experienced members of the neurolaryngology working group of the European Laryngological Society (ELS). For the measurement of the observer agreement between two raters, Cohen's Kappa statistic was calculated. For the interpretation of agreements of diagnoses among the seven examiners, we used the Fleiss' Kappa statistic. Result: When focusing on the categories "no activity", "single fiber pattern", and "strongly decreased recruitment pattern", the inter-rater agreement varied from Cohen's Kappa values between 0.48 and 0.84, indicating moderate to near-perfect agreement between the rater pairs. Calculating with Fleiss' Kappa, a value of 0.61 showed good agreement among the seven raters. For the rating categories, the Fleiss' Kappa value ranged from 0.52 to 0.74, which also showed a good agreement. Conclusion: A good inter-rater agreement between the participating neurolaryngologists was achieved in the interpretation of LEMGs. More instructional courses should be offered to broadly implement LEMG as a reliable diagnostic tool in evaluating vocal fold movement disorders in clinical routine and to develop future algorithms for therapy and computer-assisted examination. [ABSTRACT FROM AUTHOR]

Tennis is a very popular sport in the world. Many researchers have worked in the fields of forecasting the outcome of tennis matches using past statistical data records. This paper mainly investigates the comparison between three different classifiers namely decision tree, learning vector quantization and support vector machine. The research study aims to predict the result of tennis singles matches using eight UCI databases of grand slam tennis tournaments and evaluate the classification performance using various measures such as the root-mean-square error, accuracy, false positive rate, true positive rate, kappa statistic, recall, precision, and f-measure. All these performance measures confirm the supremacy of the decision tree classification algorithm compared to the others. [ABSTRACT FROM AUTHOR]

In this article, some misuses of Kappa statistic in the original paper [Chemosphere, 307, 135831] are discussed. By using DRASTIC and Analytic Hierarchy Process (AHP) models, the authors have assessed the groundwater vulnerability of Totko, India. High nitrate concentrations in groundwater have been found in highly vulnerable areas, and the accuracy of the models has been assessed through Pearson's correlation coefficient and Kappa coefficient. However, using Cohen's Kappa to estimate the intra-rater reliabilities (IRRs) of the two models is not appropriate on the condition of ordinal categorical variables in five categories in the original paper. We briefly introduce the Kappa statistic and propose to use weighted Kappa to compute IRRs under such conditions. To conclude, we recognize that this does not significantly alter the conclusions of the original paper, but it is necessary to ensure that the appropriate statistical tools are used. [Display omitted] • Cohen's Kappa assesses IRR for 2 or ≥3 unordered categorical variables categories. • Weighted Kappa measures IRR for ordered categorical variables with ≥3 categories. • Fleiss' Kappa evaluates IRR for three or more raters. [ABSTRACT FROM AUTHOR]

ABSTRACT Multi-model ensembles ( MMEs) have been demonstrated to be useful for improving the results of models. Furthermore, previous research suggests that weighted MMEs outperform unweighted multi-model results in climatological simulations, with the degree of difference in model performance dependent on the suitability of the weighting scheme. The goal of this research is to improve the results of MMEs by optimizing the weighting for each model for predicting the distribution of Köppen-Geiger climatic types. Results suggest that the correspondence between general circulation model- ( GCM-) based and Climate Research Unit- ( CRU-) based output of the geographic distribution of the Köppen-Geiger climatic types is inadequate for nine GCMs simulations, with only 40-52% of the total land area having agreement for the Köppen climatic type. An unweighted ensemble average GCM-based simulation produced only marginally improved model performance. However, the terrestrial area with disagreement between the MMEs and CRU was reduced to about 35% by using the nonlinear-weighted ensemble average. Inconsistent regions between the MMEs and CRU are concentrated along the climatic boundaries, confirming that ecotones are simulated poorly by these models. Because, the Köppen classification is designed so that climatic regions correspond to biomes, this research may have implications for improving simulation of agricultural, forestry, and other biotic realms under past and future climatic conditions. [ABSTRACT FROM AUTHOR]

Dichotomization of continuous variables to discriminate a dichotomous outcome is often useful in statistical applications. If a true threshold for a continuous variable exists, the challenge is identifying it. This paper examines common methods for dichotomization to identify which ones recover a true threshold. We provide mathematical and numeric proofs demonstrating that maximizing the odds ratio, Youden’s statistic, Gini Index, chi-square statistic, relative risk and kappa statistic all theoretically recover a true threshold. A simulation study evaluating the ability of these statistics to recover a threshold when sampling from a population indicates that maximizing the chi-square statistic and Gini Index have the smallest bias and variability when the probability of being larger than the threshold is small while maximizing Kappa or Youden’s statistics is best when this probability is larger. Maximizing odds ratio is the most variable and biased of the methods. [ABSTRACT FROM PUBLISHER]

Background: The management of plantar corns and callus has a low cost-benefit with reduced prioritisation in healthcare. The distinction between types of keratin lesions that forms corns and callus has attracted limited interest. Observation is imperative to improving diagnostic predictions and a number of studies point to some confusion as to how best to achieve this. The use of photographic observation has been proposed to improve our understanding of intractable keratin lesions. Methods: Students from a podiatry school reviewed photographs where plantar keratin lesions were divided into four nominal groups; light callus (Grade 1), heavy defined callus (Grade 2), concentric keratin plugs (Grade 3) and callus with deeper density changes under the forefoot (Grade 4). A group of 'experts' assigned from qualified podiatrists validated the observer rated responses by the students. Results: Cohen's weighted statistic (k) was used to measure inter-observer reliability. First year students (unskilled) performed less well when viewing photographs (k = 0.33) compared to third year students (semi-skilled, k = 0.62). The experts performed better than students (k = 0.88) providing consistency with wound care models in other studies. Conclusions: Improved clinical annotation of clinical features, supported by classification of keratin-based lesions, combined with patient outcome tools, could improve the scientific rationale to prioritise patient care. Problems associated with photographic assessment involves trying to differentiate similar lesions without the benefit of direct palpation. Direct observation of callus with and without debridement requires further investigation alongside the model proposed in this paper. [ABSTRACT FROM AUTHOR]

Background Management of children with necrotizing enterocolitis (NEC) remains challenging. Various scores try to facilitate therapeutic decision-making. We aim to assess the agreement of three scores intending to predict the need for surgery and/or mortality in our patient cohort, and analyze agreement between the different scores. Methods This study is a retrospective analysis of patients with NEC Bell's stage II and III, managed in a single institution (1991-2011). Three existing scores (Metabolic Derangement Acuity score, NEC score, Detroit score) were calculated individually for each patient. The agreement between predicted outcome by scores and real outcome was evaluated with kappa statistic. Results Of 57 children, 46% presented with NEC stage II, 54% with stage III, 46% were treated with surgery, 54% conservatively, and survival was 58%. The kappa indexes for "need for surgery" were 0.41, 0.13, and 0.12 and kappa indexes for "mortality" were 0.27, 0.04, and 0.1 for the Metabolic Derangement Acuity score, the NEC score, and the Detroit score, respectively. Conclusion In our cohort, the agreement between the predicted outcomes by scores and the real need for surgery and/or mortality was poor. There was a lack of clinical usefulness of the tested scores. We must continue to better identify parameters to help guide the management of these patients. [ABSTRACT FROM AUTHOR]

N95 filtering facepiece respirators are used by healthcare workers when there is a risk of exposure to airborne hazards during aerosol-generating procedures. Respirator fit-testing is required prior to use to ensure that the selected respirator provides an adequate face seal. Two common fit-test methods can be employed: qualitative fit-test (QLFT) or quantitative fit-test (QNFT). Respiratory protection standards deem both fit-tests to be acceptable. However, previous studies have indicated that fit-test results may differ between QLFT and QNFT and that the outcomes may also be influenced by the type of respirator model. The aim of this study was to determine if there is a difference in fit-test outcomes with our suite of respirators, 3M - 1860S, 1860, AND 1870, and whether the model impacts the fit-test results. Subjects were recruited from residential care facilities. Each participant was assigned a respirator and underwent sequential QLFT and QNFT fit-tests and the results (either pass or fail) were recorded. To ascertain the degree of agreement between the two fit-tests, a Kappa (Κ) statistic was conducted as per the American National Standards Institute (ANSI) respiratory protection standard. The pass-fail rates were stratified by respirator model and a Kappa statistic was calculated for each to determine effect of model on fit-test outcomes. We had 619 participants and the aggregate Κ statistic for all respirators was 0.63 which is below the suggested ANSI threshold of 0.70. There was no statistically significant difference in results when stratified by respirator model. QNFT and QLFT produced different fit-test outcomes for the three respirator models examined. The disagreement in outcomes between the two fit-test methods with our suite of N95 filtering facepiece respirators was approximately 12%. Our findings may benefit other healthcare organizations that use these three respirators. [ABSTRACT FROM PUBLISHER]

This study aims to determine the Type I error rates and power of S1, S2 indices and kappa statistic at detecting copying on multiple-choice tests under various conditions. It also aims to determine how copying groups are created in order to calculate how kappa statistics affect Type I error rates and power. In this study, option-matrices were obtained by using five choices of multiple choice test data generation. R-3.0 software was used for data generation and analysis. The effects of sample size, test length, and source ability level on Type I error rates and also amount of copying on power according to nominal α-levels were investigated. The findings indicated that Type I error rates for S1 and S2 indices were lower in all conditions, while the same error rates were relatively higher for copy detection using kappa statistics. Kappa statistics were seen to be more powerful than S1 and S2 indices under all conditions. As sample size, test length, and amount of copying increased, the S2 index was also revealed to be more sensitive than the S1 index. Type I error rates and power results of the kappa statistics were similar to each other. [ABSTRACT FROM AUTHOR]

Background Context: Accurately evaluating the extent of trunk imbalance in the coronal plane is significant for patients before and after treatment. We preliminarily practiced a new method, axis-line-angle technique (ALAT), for evaluating coronal trunk imbalance with excellent intra-observer and interobserver reliability. Radiologists and surgeons were encouraged to use this method in clinical practice. However, the optimal cutoff value of the ALAT for determination of the extent of coronal trunk imbalance has not been calculated up to now.Purpose: The purpose of this study was to identify the cutoff value of the ALAT that best predicts a positive measurement point to assess coronal balance or imbalance.Study Design/setting: A retrospective study at a university affiliated hospital was carried out.Patient Sample: A total of 130 patients with C7-central sacral vertical line (CSVL) >0 mm and aged 10-18 years were recruited in this study from September 2013 to December 2014.Outcome Measures: Data were analyzed to determine the optimal cutoff value of the ALAT measurement.Methods: The C7-CSVL and ALAT measurements were conducted respectively twice on plain film within a 2-week interval by two radiologists. The optimal cutoff value of the ALAT was analyzed via receiver operating characteristic (ROC) curve. Comparison variables were performed with chi-square test between the C7-CSVL and ALAT measurements for evaluating trunk imbalance. Kappa agreement coefficient method was used to test the intra-observer and interobserver agreement of C7-CSVL and ALAT.Results: The ROC curve area for the ALAT was 0.82 (95% confidence interval: 0.753-0.894, p<.001). The maximum Youden index was 0.51, and the corresponding cutoff point was 2.59°. No statistical difference was found between the C7-CSVL and ALAT measurements for evaluating trunk imbalance (p>.05). Intra-observer agreement values for the C7-CSVL measurements by observers 1 and 2 were 0.79 and 0.91 (p<.001), respectively, whereas intra-observer agreement values for the ALAT measurements were both 0.89 by observers 1 and 2 (p<.001). The interobserver agreement values for the first and second measurements with the C7-CSVL were 0.78 and 0.85 (p<.001), respectively, whereas the interobserver agreement values for the first and second measurements with the ALAT were 0.91 and 0.88 (p<.001), respectively.Conclusions: The newly developed ALAT provided an acceptable optimal cutoff value for evaluating trunk imbalance in the coronal plane with a high level of intra-observer and interobserver agreement, which suggests that the ALAT is suitable for clinical use. [ABSTRACT FROM AUTHOR]

Crucial therapeutic decisions are based on diagnostic tests. Therefore, it is important to evaluate such tests before adopting them for routine use. Although things such as blood tests, cultures, biopsies, and radiological imaging are obvious diagnostic tests, it is not to be forgotten that specific clinical examination procedures, scoring systems based on physiological or psychological evaluation, and ratings based on questionnaires are also diagnostic tests and therefore merit similar evaluation. In the simplest scenario, a diagnostic test will give either a positive (disease likely) or negative (disease unlikely) result. Ideally, all those with the disease should be classified by a test as positive and all those without the disease as negative. Unfortunately, practically no test gives 100% accurate results. Therefore, leaving aside the economic question, the performance of diagnostic tests is evaluated on the basis of certain indices such as sensitivity, specificity, positive predictive value, and negative predictive value. Likelihood ratios combine information on specificity and sensitivity to expresses the likelihood that a given test result would occur in a subject with a disorder compared to the probability that the same result would occur in a subject without the disorder. Not all test can be categorized simply as "positive" or "negative." Physicians are frequently exposed to test results on a numerical scale, and in such cases, judgment is required in choosing a cutoff point to distinguish normal from abnormal. Naturally, a cutoff value should provide the greatest predictive accuracy, but there is a trade-off between sensitivity and specificity here - if the cutoff is too low, it will identify most patients who have the disease (high sensitivity) but will also incorrectly identify many who do not (low specificity). A receiver operating characteristic curve plots pairs of sensitivity versus (1 - specificity) values and helps in selecting an optimum cutoff -- the one lying on the "elbow" of the curve. Cohen's kappa (κ) statistic is a measure of inter-rater agreement for categorical variables. It can also be applied to assess how far two tests agree with respect to diagnostic categorization. It is generally thought to be a more robust measure than simple percent agreement calculation since kappa takes into account the agreement occurring by chance. [ABSTRACT FROM AUTHOR]

dos Santos Teixeira et al. evaluated the effectiveness of three different sensors, portable X-ray fluorescence (pXRF) spectrometry, visible near-infrared (Vis-NIR), and NixPro TM color sensor, in predicting six soil properties including sum of bases (SB), effective cation exchange capacity (eCEC), potential cation exchange capacity (CEC), base saturation (BS), soil organic matter (SOM) content, and soil pH, and compared their performance when used alone or in combination. Preprocessing methods and other variables were also analyzed. In this comment paper, some misuses of Kappa statistic in the original paper by dos Santos Teixeira et al. are discussed. The authors calculated Cohen's kappa coefficient to make categorical predictions for soil fertility classes. However, using Cohen's Kappa to estimate the intra-rater reliabilities (IRRs) is not appropriate on the condition of ordinal categorical variables in four or five categories in the original paper. We briefly introduce the Kappa statistic for evaluation of IRR between two raters and propose to use weighted Kappa to compute IRRs under such conditions. To conclude, we recognize that this does not significantly alter the conclusions of this paper, but it is necessary to ensure that the appropriate statistical tools are used. • Cohen's Kappa assesses IRR for 2 or ≥3 unordered categorical variables categories. • Weighted Kappa measures IRR for ordered categorical variables with ≥3 categories. • QWK reveals more inconsistencies than LWK. [ABSTRACT FROM AUTHOR]

Background and Objectives: Antibacterial susceptibility testing of clinical bacterial isolates through disk diffusion method plays a major role in antibacterial treatment. One of the main factors affecting the result of these tests is the type, structure and quality of the disks. The main objective of this study was to compare the agreement of antibiotic disks originated from three companies on Quicolor and Mueller-Hinton agar. Materials and Methods: Quicolor and Mueller-Hinton agar media were used in disk diffusion method. Seventy clinical isolates from Enterobacteriaceae family (21 Klebsiella spp., 36 Escherichia coli, 1 Enterobacter spp. and 12 Shigella spp.) were investigated in the study. After obtaining data, the results were interpreted as resistant, sensitive or intermediate. Kappa coefficient measured the agreement of two media. Coefficient of variation (CV) was also calculated for antibiotic disks. Results: The kappa agreement values for three types of antibiotic disks on Quicolor and Mueller-Hinton agar plates were good or excellent for all the examined antibiotics. CV values were also very satisfactory in the majority of cases. Conclusion: Antibiotic disks from three manufacturers can successfully be used on both Quicolor and Mueller-Hinton agar plates.

The importance of understanding spatial variability of soils is connected to crop management planning. This understanding makes it possible to treat soil not as a uniform, but a variable entity, and it enables site-specific management to increase production efficiency, which is the target of precision agriculture. Questions remain as the optimum soil sampling interval needed to make site-specific fertilizer recommendations in Brazil. The objectives of this study were: i) to evaluate the spatial variability of the main attributes that influence fertilization recommendations, using georeferenced soil samples arranged in grid patterns of different resolutions; ii) to compare the spatial maps generated with those obtained with the standard sampling of 1 sample ha-1, in order to verify the appropriateness of the spatial resolution. The attributes evaluated were phosphorus (P), potassium (K), organic matter (OM), base saturation (V%) and clay. Soil samples were collected in a 100 × 100 m georeferenced grid. Thinning was performed in order to create a grid with one sample every 2.07, 2.88, 3.75 and 7.20 ha. Geostatistical techniques, such as semivariogram and interpolation using kriging, were used to analyze the attributes at the different grid resolutions. This analysis was performed with the Vesper software package. The maps created by this method were compared using the kappa statistics. Additionally, correlation graphs were drawn by plotting the observed values against the estimated values using cross-validation. P, K and V%, a finer sampling resolution than the one using 1 sample ha-1 is required, while for OM and clay coarser resolutions of one sample every two and three hectares, respectively, may be acceptable.A importância de compreender a variabilidade espacial do solo está conectada ao planejamento do manejo das culturas. Este entendimento faz com que seja possível tratar o solo não como uma entidade uniforme, mas variável, e permite o gerenciamento de sítios específicos para aumentar a eficiência de produção, que é o objetivo da agricultura de precisão. Questões relacionadas com a otimização do intervalo de amostragem do solo se faz necessário para a realização das recomendações de adubações no Brasil. Os objetivos deste estudo foram: i) avaliar a variabilidade espacial dos principais atributos que influenciam as recomendações de adubação, usando amostras de solos georreferenciadas dispostas em padrões de grades de diferentes resoluções; ii) comparar os mapas espaciais gerados com o mapa padrão obtido com amostragem de 1 amostra ha-1, a fim de verificar a adequação da resolução espacial. Os atributos avaliados foram fósforo (P), potássio (K), matéria orgânica (MO), saturação por bases (V%) e argila. As amostras de solos foram coletadas numa grade de 100 × 100 m e georreferenciadas. Um desbaste foi realizado, criando-se uma grade com 1 amostra a cada 2,07, 2,88, 3,75 e 7,20 ha. Técnicas de geoestatística, como semivariograma e interpolação usando krigagem, foram utilizadas para analisar os atributos nas grades com diferentes resoluções. Esta análise foi realizada com o programa computacional Vesper. Os mapas criados por este método foram comparados utilizando-se a estatística kappa. Além disso, gráficos de correlação foram construídos plotando-se os valores observados pelos valores estimados utilizando-se a validação cruzada. Para P, K e V%, uma amostragem de resolução mais fina do que aquela usando 1 amostra ha-1 foi necessária, enquanto que para MO e argila, resoluções mais grosseiras de uma amostra ou dois em dois e três hectares, respectivamente, pode ser aceitável.

Objective: To assess whether adolescents could be relied on as proxies to provide accurate information about their parental socio-economic status. Methodology: A descriptive cross-sectional study was conducted among 1225, 15-year-olds selected from 42 schools in the Colombo district using a stratified cluster sampling technique. Data were collected by means of self-administered questionnaires to both adolescents and their parents. Results: Response rates of adolescents regarding their parents' occupation status were very high. The strength of agreement between parental and adolescents reports was assessed using the Kappa statistic. The respective kappa statistics (95% CI) were 0.84 (0.82-0.86) for fathers occupation and 0.85 (0.82- 0.88) for mother's occupation. Conclusion: the results indicated that 15-year-old adolescents could be considered as proxies to provide accurate information about their parents' occupational status. Key words: occupation; questionnaires; Kappa statistic; adolescentsDOI: 10.4038/jccpsl.v14i1.2942Journal of the College of Community Physicians of Sri Lanka Vol.14(1) 2009 9-13

We propose adjusted inference procedures for evaluating the agreement/disagreement of two raters in a clustered setting involving twins or paired body parts. These procedures include the construction of a confidence interval for the kappa statistic, a related test of statistical significance and a formula that facilitates sample size estimation. The results of a simulation study suggest that a simple adjustment using an estimated design effect will provide valid inferences. The methods proposed are illustrated using an example from the literature. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Evaluation of inter and intraobserver reproducibility of by the visual method interpretation of cineangiogram in a clinically based context. METHODS: Five interventional cardiologists analyzed 11 segments of 8 coronary cineangiograms at a two month apart sessions. The percent luminal reduction by the lesions were analyzed by two different classifications: in one (A) the lesions were graded in 0% = absent, 1-50% = mild, 51 - 69 = moderate, and > or = 70% = severe; the other classification (B) was a dichotomic one : or = 70%=significant lesions. The agreement were measured by the kappa (k) index. RESULTS: Interobserver agreement was moderate for classification A (1st measurement, k = 0.36 -- 0.63, k m = 0.49; 2nd measurement, k = 0.39-0.68, k m = 0.52) and good for classification B (1st measurement, k = 0.55-0.73, k m = 0.63; 2nd measurement, k = 0.37-0.82, k m = 0.61). Intraobserver levels of agreement were k = 0.57-0.95 for classification A and 0.62-1.0 for classification B. CONCLUSION: The higher level of reproducibility obtained by adopting the dichotomous criteria usually considered for ischemic limits demonstrates that in the present clinical context, the reliability of the simple visual method is adequate for the identification of patients with clinically significant lesions and candidates for myocardial revascularization procedures.