Confiabilidad de una escala de valoración de resúmenes para congresos

Introducción: En 2013, desarrollamos una escala, para evaluar resúmenes de congresos de la Sociedad de Cirujanos de Chile (SOCICH). Objetivo: Determinar consistencia interna y confiabilidad interobservador de una escala para evaluar resúmenes de congresos. Material y Método: Estudio de confiabilidad. Doce cirujanos fueron capacitados de forma virtual durante 8 horas, para aplicar la escala. Una vez finalizado el entrenamiento, se les envió un cuestionario para evaluar contenidos de la capacitación, y varios resúmenescasos para ser evaluados con la escala antes señalada. Se aplicó estadística descriptiva, luego se estimó el grado de acuerdo entre observadores para cada ítem de la escala. Posteriormente, se evaluó el coeficiente de correlación (CCI), utilizando un modelo de dos factores mixtos en el que los efectos de los evaluadores son aleatorios y los ítems fijos; utilizando una definición de acuerdo absoluto. Además, se evaluó la consistencia interna de los ítems utilizando alfa de Cronbach, considerando intérvalos de confianza del 95% (IC 95%). Resultados: Luego de analizar las mediciones de los 9 ítems por los 12 observadores, se verificó que el CCI fue de 0,871; con un IC 95% de 0,700; 0,965. El valor de la consistencia interna fue de 0,7 considerando los 9 ítems, no se recomienda eliminar ningún ítem. Conclusión: La escala tiene buena confiabilidad interobservador y los ítems son consistentes entre sí; por lo que puede ser considerada como un instrumento confiable para la valoración de resúmenes de congresos.

Background: In 2013, we developed a scale to evaluate the abstracts of the congresses of the Society of Surgeons of Chile (SOCICH). Objective: To determine internal consistency and interobserver reliability of a scale to evaluate conference abstracts. Material and Methods: Reliability study. Twelve surgeons were trained virtually for 8 hours, to apply the scale. Once the training was finished, they were sent a questionnaire to evaluate the contents of the training, and several summaries-cases to be evaluated with the aforementioned scale. Descriptive statistics were applied, then the degree of agreement between observers was estimated for each item of the scale. Subsequently, intraclass correlation coefficient (ICC) was evaluated, using a mixed two-factor model where the effects of the evaluators are random and the items are fixed, using a definition of absolute agreement. In addition, the internal consistency of the items was evaluated using Cronbach's alpha, considering 95% confidence intervals (95% CI). Results: After analyzing the measurements of the 9 items by the 12 observers, it was verified that the ICC was 0.871; with a 95% CI of 0.700; 0.965. The internal consistency value was 0.7 considering the 9 items, it is not recommended to delete any item. Conclusions: The scale has good internal consistency and interobserver reliability. Therefore, it can be considered as reliable instrument to be used in the evaluation of abstracts for congresses.

Reproducibility Analysis of Iodine Concentrations of Abdominal Parenchymal Organs Based on Spectral CT / 中国医学科学院学报

Objective To investigate the intra-and inter-observer reproducibility of iodine concentrations of abdominal parenchymal organs based on spectral CT.Methods The water-free iodine images of the venous phase were retrospectively obtained from 50 patients with abdominal dynamic spectral CT scans.The iodine concentrations were measured in the left,right and caudate lobes of liver,spleen,pancreas and bilateral kidneys.Intraclass correlation coefficient(ICC)and Bland-Altman plot were employed to analyze the intra-and inter-observer reproducibility.Results The intra-observer ICCs of the left,right and caudate lobes of liver,spleen,pancreas,and left and right kidneys were 0.938(0.894,0.965),0.932(0.884,0.961),0.939(0.895,0.965),0.947(0.909,0.970),0.912(0.851,0.949),0.946(0.906,0.969)and 0.907(0.842,0.946),which indicated good intra-observer reproducibility.The inter-observer ICCs of the left,right and caudate lobes of liver,spleen,pancreas,and left and right kidneys were 0.947(0.909,0.970),0.927(0.875,0.958),0.943(0.902,0.968),0.956(0.924,0.975),0.934(0.887,0.962),0.927(0.875,0.958)and 0.892(0.818,0.937),which indicated good inter-observer reproducibility.Bland-Altman plots presented that more than 95% points of the intra-observer differences located within 95% CI of limits of agreement for the caudate lobe of liver,spleen,pancreas and bilateral kidneys,which was same as inter-observer differences of the caudate lobe of liver,spleen and right kidney.Conclusion The iodine concentration measurement based on the spectral CT presented good intra-and inter-observer reproducibility for the caudate lobe of liver and spleen.

Reliability of an isometric test for measuring the strength of the hip abductors and adductors / Confiabilidade de um teste isométrico para medir a força dos abdutores e adutores do quadril

This study aimed to measure the reliability of a test for measuring the strength and strength imbalance of the hip abductors and adductors, using isokinetic equipment adapted for isometric testing. Thirteen healthy, physically active male individuals took part in the research. Two unilateral isometric tests were undertaken using a load cell attached to an adapted abductor bench machine: a hip abduction test and hip adduction test. Tests consisted of two maximum voluntary isometric contractions made for six seconds with a break of one minute between each. The following dynamic variables were measured: maximum force, mean force, rate of force development for each limb (right and left), and the existence of asymmetries between the limbs. For statistical analysis, the t-test, intraclass correlation coefficient (ICC), and standard error of measurement (SEM) were applied. Results: The methodology utilized for the evaluation of the hip abductors and adductors did not show reliability in most of the parameters researched, with the ICC neither sufficient or low, and the retest performance higher than the test (p < 0.05). The applied test was not reliable for assessing strength and strength imbalances of hip abductors and adductors in most of the parameters investigated. These results indicate that the hip joints, more precisely, the abductor and adductor muscles, are complex structures to be assessed. They need to be previously familiarized with the proposed exercise, as their performance does not occur habitually. It is recommended to develop new tests in order to measure hip abduction and adduction strength adding a prior familiarization procedure

O presente estudo teve como objetivo avaliar a confiabilidade de um teste para avaliação da força e desequilíbrios de força de abdutores e adutores de quadril utilizando um equipamento isoinercial adaptado para isometria. Participaram do estudo 13 sujeitos saudáveis, do sexo masculino, fisicamente ativos. Foram realizados dois testes isométricos unilaterais utilizando uma célula de carga fixada em um banco abdutor adaptado: teste de Abdução de Quadril e Teste de Adução de Quadril. Os testes consistiram em duas contrações isométricas voluntárias máximas de seis segundos de duração com intervalo de um minuto entre elas. As seguintes variáveis dinâmicas foram avaliadas: Força Máxima, Força Média, Taxa de Produção de Força, para cada membro (direito e esquerdo), e a existência de assimetrias entre membros. Para análise estatística foram realizados teste t, coeficiente de correlação intraclasse (CCI) e erro padrão de medida. Resultados: A metodologia empregada para avaliação de adutores e abdutores de quadril não se mostrou confiável na maioria dos parâmetros investigados, com valores de CCI não significativos ou baixos, e o desempenho no reteste foi superior ao teste (p<0,05). O teste empregado não se mostrou confiável para avaliação da força e desequilíbrios de força de abdutores e adutores do quadril na maioria dos parâmetros investigados . Esses resultados demonstram que a articulação do quadril, mais precisamente os músculos abdutores e adutores, são estruturas complexas de se avaliarem, necessitando de uma familiarização prévia com o exercício proposto, por não serem movimentos realizados habitualmente. Recomenda-se novos testes para avaliação da força de adução e abdução de quadril adicionando um procedimento de familiarização prévio.

Reproducibility analysis of quantitative susceptibility mapping of cerebral subcortical nuclei in healthy adults / 南方医科大学学报

OBJECTIVE@#To investigate the intra- and inter-scanner reproducibility of quantitative susceptibility mapping (QSM) of cerebral subcortical nuclei in healthy adults.@*METHODS@#QSM was performed in 21 healthy adults on two different 3.0T MR scanners, and the region of interest (ROI) method was used to measure the magnetic susceptibility value of the left subcortical nuclei (the head of the caudate, putamen, globus pallidus, thalamus, substantia nigra and red nucleus). The intraclass correlation coefficient (ICC) and Bland-Altman method were used to evaluate the inter-scanner and intra-scanner reliability.@*RESULTS@#The ICCs of the susceptibility value ranged from 0.90 to 0.99 for all the subcortical gray nuclei except for the head of the caudate nucleus measured on the same MR scanner by the same observer. Bland-Altman analysis revealed that the points with susceptibility differences for all the subcortical gray nuclei except for substantia nigra located in the 95% CI of limits of agreement for the same MR scanner. The ICCs of the susceptibility value for the inter-scanner was 0.49 (0.08-0.75) for the head of the caudate nuleus, 0.80 (0.57-0.91) for the putamen, 0.77 (0.51-0.90) for the globus pallidus, 0.78 (0.54-0.91) for the thalamus, 0.80 (0.56-0.91) for the substantia nigra and 0.93 (0.83-0.97) for the red nucleus. The points with susceptibility difference (95.2%, 20/21) located in the 95% CI of limits of agreement for the putamen and the thalamus measured on two different MR scanners.@*CONCLUSIONS@#The intra-scanner reproducibility of QSM of the subcortical gray nuclei is superior to the inter-scanner reproducibility in healthy adults.

Reliability study in the measurement of the cusp inclination angle of a chairside digital model / 华西口腔医学杂志

OBJECTIVE@#This study aims to evaluate the reliability of the software Picpick in the measurement of the cusp inclination angle of a digital model.@*METHODS@#Twenty-one trimmed models were used as experimental objects. The chairside digital impression was then used for the acquisition of 3D digital models, and the software Picpick was employed for the measurement of the cusp inclination of these models. The measurements were repeated three times, and the results were compared with a gold standard, which was a manually measured experimental model cusp angle. The intraclass correlation coefficient (ICC) was calculated.@*RESULTS@#The paired t test value of the two measurement methods was 0.91. The ICCs between the two measurement methods and three repeated measurements were greater than 0.9. The digital model achieved a smaller coefficient of variation (9.9%).@*CONCLUSIONS@#The software Picpick is reliable in measuring the cusp inclination of a digital model.

Differential Diagnosis of Colorectal Polyps with Narrow Band Imaging Colonoscopy without Magnification / 대한소화기학회지

BACKGROUND/AIMS: Narrow band imaging (NBI) endoscopy can be used for gross differentiation between the types of colonic polyps. This study was conducted as a retrospective study for estimation of the interobserver and intra-observer agreement of the pit pattern of the mucosal surface and the accuracy of histology prediction. METHODS: A total of 159 patients underwent complete colonoscopy and 219 polyps examined by NBI endoscopy without magnification were assessed. Interobserver and intra-observer agreement were calculated by investigators in each group for determination of the surface pattern and prediction of histology based on the modified Kudo's classification using intraclass correlation coefficient. RESULTS: Interobserver agreement for the surface pit pattern and prediction of polyp type was 0.84 and 0.73 in experienced endoscopists, and 0.86 and 0.62 in trainees, respectively. Intra-observer agreement for the surface pit patterns and prediction of polyp type was 0.81, 0.83, 0.85, 0.83, 0.56, 0.84, 0.51, 0.83, and 0.71; and 0.71, 0.70, 0.82, 0.54, 0.72, 0.37, 0.51, 0.34, and 0.30, respectively. The diagnostic accuracy for prediction of polyp type was 69.4% for experienced endoscopists and 72.9% for trainees. CONCLUSIONS: NBI endoscopy without magnification showed fairly good inter and intra-observer agreement for the pit pattern of the mucosal surface and the accuracy of histology prediction; however, it had some limitation for differentiation of colon polyp histologic type. Training and experience with NBI is needed for improvement of accuracy.

Confiabilidade entre sessões de avaliação de equilíbrio com TOBtrainerMR / Inter-session confidence of balance assessment with TOBtrainerMR

INTRODUÇÃO: Um novo dispositivo para a avaliação e equilíbrio dinâmico de formação, o TOBtrainerMR, foi recentemente desenvolvido. OBJETIVO: Avaliar a confiabilidade entre sessões de avaliação de equilíbrio usando o TOBtrainerMR. O estudo também tem a finalidade de dar contagens de erro para que verdadeiras mudanças no desempenho possam ser identificadas. MÉTODOS: Trinta indivíduos sedentários saudáveis (nove homens, 21 mulheres com idade de 27,9 ± 2,9 anos) participaram deste estudo. O TOBtrainerMR foi usado para avaliar o equilíbrio no plano medial-lateral com os olhos abertos (MLOA) e com os olhos fechados (MLOF) e no plano anteroposterior com os olhos abertos (APOA) e com os olhos fechados (APOF). Os indivíduos foram instruídos para estar em posição ereta com braços ao longo do corpo e mãos lateralmente tentando manter a estabilidade da plataforma. Todos os dados foram registrados com o software TOBT. RESULTADOS: As amostras foram relacionadas, testes t avaliados, efeitos de aprendizagem e coeficientes de correlação intracIasse avaliados na sua confiabilidade. Erros padrão de medição e menores diferenças detectáveis foram calculadas para avaliar o erro de medição. Não foram encontradas diferenças significativas de medição entre a primeira e a segunda sessão. Os coeficientes de correlação intraclasse, os erros padrão de medição e as menores diferenças detectáveis para as quatro modalidades medidas variavam de 0,71 0,83, 0,32º a 0,80º e 0,90º a 2,22º, respectivamente. CONCLUSÕES: A confiabilidade entre sessões para avaliação de equilíbrio utilizando o TOBtrainerMR foi boa. Futuros investigadores têm agora dados de referência para avaliar se as diferenças de duas diferentes pontuações são reais ou se devem ao erro de medição e que mudanças são necessárias na pontuação do sujeito para se ter certeza de que ocorreu uma mudança real.

INTRODUCTION: A new device for assessing and training dynamic balance, the TOBtrainerMR, has been recently developed. OBJECTIVE: To asses the inter-session reliability of balance assessment using the TOBtrainerMR. The study has also the purpose of giving error scores so that true changes in performance can be identified. METHODS: Thirty healthy sedentary subjects (nine males, 21 females, age = 27.9 ± 2.9 years) participated in this study. The TOBtrainerMR was used to assess balance in the medial-lateral plane with eyes open (MLEO) and with eyes closed (MLEC), and in the anterior-posterior plane with eyes open (APEO) and with eyes closed (APEC). Subjects were instructed to be in a double-limb standing position with the hands at their sides trying to maintain platform stability. All the data were registered with the TOBT software. RESULTS: The samples were correlated, t-Tests assessed, learning effects and Intraclass Correlation Coefficients assessed in their reliability. Standard Errors of Measurement and Smallest Detectable Differences were calculated to assess measurement error. No significant differences between the first and the second session measurements were found. The Intraclass Correlation Coefficients, the Standard Errors of Measurement and the Smallest Detectable Differences for the four modalities measured ranged from 0.71 to 0.83, 0.32º to 0.80º and 0.90º to 2.22º, respectively. CONCLUSIONS: Inter-session reliability for balance assessment using the TOBtrainerMR was good. Future researchers have now reference data to evaluate whether differences in two different scores are real or due to measurement error and what changes are needed in a subject's score to be sure that a real change has occurred.

Validity of self-reported weight and stature in adolescents from Cuiabá, Central-Western Brazil / Validade de peso e estatura autorreferidos em adolescentes de Cuiabá, Região Centro-Oeste do Brasil

OBJECTIVE: This study assessed the agreement between self-reported and measured weight and stature in adolescents. METHODS: Ninety-seven students from public and private high schools of Cuiabá, in the state of Mato Grosso, Brazil (14 to 19 years old), were examined to assess the validity of self-reported weight and stature. The adolescents reported their weight and stature, which were subsequently measured by standard procedures. The body mass index was calculated from both self-reported and measured data. Weight status was classified according to body mass index Z-score and World Health Organization criteria. The differences between the self-reported and measured means were tested by the Student's paired t-test. Weighted Kappa's coefficient of agreement was used to assess the variations in weight status categorization using informed and measured data. Agreement between measurements was assessed by the Bland-Altman method and intraclass correlation coefficient. RESULTS: The means of self-reported and measured weights (p=0.30), statures (p=0.76) and body mass index (p=0.47) were not significantly different. There was high agreement between self-reported and measured measurements according to intraclass correlation coefficient (weight: r=0.99; stature: r=0.96; body mass index: r=0.97) and the mean agreements estimated by the Bland-Altman method were 99% for weight and 100% for stature. CONCLUSION: Given the excellent agreement with measured data, self-reported weight and stature are considered valid to be used in epidemiological studies on adolescents of Cuiabá, Mato Grosso, Brazil.

OBJETIVO: Avaliar a concordância entre as medidas de peso e estatura autorreferidas e aferidas em adolescentes. MÉTODOS: Noventa e sete estudantes de 14 a 19 anos de idade do ensino médio público e privado de Cuiabá, (Mato Grosso) foram examinados a fim de se avaliar a validade de medidas de peso e estatura autorreferidas. Os adolescentes referiram o peso e a estatura e, na sequência, as respectivas medidas foram aferidas com base em procedimentos padronizados. O índice de massa corporal foi determinado a partir das medidas estimadas e aferidas. O status de peso foi classificado com base no escore-Z do índice de massa corporal segundo proposta da Organização Mundial da Saúde. Utilizou-se o teste t de Student pareado para avaliar as diferenças entre as médias das medidas autorreferidas e aferidas. O coeficiente de concordância Kappa ponderado foi utilizado para se avaliarem as variações na categorização do status de peso estimado a partir de medidas informadas e aferidas. A concordância entre as medidas foi avaliada pelo método de Bland-Altman e pelo coeficiente de correlação intraclasse. RESULTADOS: Não se observaram diferenças entre as médias das medidas autorreferidas e aferidas de peso (p=0,30),: estatura (p=0,76) e índice de massa corporal (p=0,47). Houve elevada concordância entre as medidas autorreferidas e aferidas de acordo com o coeficiente de correlação intraclasse (peso: r=0,99; estatura: r=0,96; índice de massa corporal; r=0,97) e segundo o método de Bland-Altman (concordância média: peso=99%; estatura=100%). CONCLUSÃO: Dada a excelente concordância com as medidas aferidas, o peso e a estatura autorreferidos são considerados válidos para serem utilizados em estudos epidemiológicos com adolescentes de Cuiabá.

Non-parametric Bootstrap estimation on the intraclass correlation coefficient generated from quantitative hierarchical data / 中华流行病学杂志

This paper aims to achieve Bootstraping in hierarchical data and to provide a method for the estimation on confidence interval (CI) of intraclass correlation coefficient (ICC).First,we utilize the mixed-effects model to estimate data from ICC of repeated measurement and from the two-stage sampling.Then,we use Bootstrap method to estimate CI from related ICCs.Finally,the influences of different Bootstraping strategies to ICC' s CIs are compared.The repeated measurement instance show that the CI of cluster Bootsraping containing the true ICC value.However,when ignoring the hierarchy characteristics of data,the random Bootsraping method shows that it has the invalid CI.Result from the two-stage instance shows that bias obsered between cluster Bootstraping's ICC means while the ICC of the original sample is the smallest,but with wide CI.It is necessary to consider the structure of data as important,when hierarchical data is being resampled.Bootstrapping seems to be better on the higher than that on lower levels.

Pitfalls and Important Issues in Testing Reliability Using Intraclass Correlation Coefficients in Orthopaedic Research

BACKGROUND: Intra-class correlation coefficients (ICCs) provide a statistical means of testing the reliability. However, their interpretation is not well documented in the orthopedic field. The purpose of this study was to investigate the use of ICCs in the orthopedic literature and to demonstrate pitfalls regarding their use. METHODS: First, orthopedic articles that used ICCs were retrieved from the Pubmed database, and journal demography, ICC models and concurrent statistics used were evaluated. Second, reliability test was performed on three common physical examinations in cerebral palsy, namely, the Thomas test, the Staheli test, and popliteal angle measurement. Thirty patients were assessed by three orthopedic surgeons to explore the statistical methods testing reliability. Third, the factors affecting the ICC values were examined by simulating the data sets based on the physical examination data where the ranges, slopes, and interobserver variability were modified. RESULTS: Of the 92 orthopedic articles identified, 58 articles (63%) did not clarify the ICC model used, and only 5 articles (5%) described all models, types, and measures. In reliability testing, although the popliteal angle showed a larger mean absolute difference than the Thomas test and the Staheli test, the ICC of popliteal angle was higher, which was believed to be contrary to the context of measurement. In addition, the ICC values were affected by the model, type, and measures used. In simulated data sets, the ICC showed higher values when the range of data sets were larger, the slopes of the data sets were parallel, and the interobserver variability was smaller. CONCLUSIONS: Care should be taken when interpreting the absolute ICC values, i.e., a higher ICC does not necessarily mean less variability because the ICC values can also be affected by various factors. The authors recommend that researchers clarify ICC models used and ICC values are interpreted in the context of measurement.

Concordância de medidas antropométricas em estudo epidemiológico de base populacional: Ribeirão Preto, SP, 2006. Projeto OBEDIARP / Agreement of anthropometric measures in a population-based epidemiological study: Ribeirão Preto, SP, 2006. OBEDIARP Project

O objetivo do estudo foi avaliar o acordo de medidas antropométricas aferidas e referidas de peso e altura em 632 adultos. O acordo foi calculado por meio do coeficiente de correlação intraclasse, obtido por análise de variância com 01 critério de classificação, e pelas diferenças médias e limites de acordo, segundo Bland e Altman. O acordo intracategorias do estado nutricional foi avaliado pela estatística kappa. No sexo masculino, os CCIs foram 0,926 (IC95 por cento: 0,894-0,959) e 0,873 (IC95 por cento: 0,799-0,946), para medidas de peso e altura, respectivamente, sendo a diferença média e os limites de acordo para o IMC de 0,143kg/m² (-2,844-3,129). No sexo feminino, os respectivos CCIs foram 0,981 (IC95 por cento: 0,973-0,988) e 0,794 (IC95 por cento: 0,687-0,900), sendo a diferença e os limites de acordo para o IMC de 0,462kg/m² (-2,457-3,382). Os coeficientes kappa para o estado nutricional, no sexo masculino e feminino, foram, respectivamente, 0,777 (IC95 por cento: 0,683-0,872) e 0,793(IC95 por cento: 0,725-0,862). As medidas referidas são alternativas apropriadas para a classificação do estado nutricional em estudos epidemiológicos.

This study aimed to assess the agreement between measured and self-reported height and weight measures in 632 adults. The agreement was calculated using an intra-class correlation coefficient (estimated by ANOVA using one classification criterion), mean differences and agreement limits, according to Bland and Altman. The intra-category agreement of the nutritional status was assessed by Kappa statistics. In men, ICCs were 0.926 (95 percentCI: 0.894-0.959) and 0.873 (95 percentCI: 0.799-0.946), for weight and height measures, respectively, with the following mean difference and agreement limits for BMI: 0.143kg/m² (-2.844-3.129). In women, ICCs were 0.981 (95 percentCI: 0.973-0.988) and 0.794 (95 percentCI: 0.687-0.900) respectively, with the following mean difference and agreement limits for BMI: 0.462kg/m² (-2.457-3.382). Kappa coefficients for nutritional status in men and women were, respectively, 0.777 (95 percentCI: 0.683-0.872) and 0.793 (95 percentCI: 0.725-0.862). Self-reported measures are appropriate alternatives to classify nutritional status in epidemiological studies.

Intra-and interobserver reliability of analysis of lower limb alignment on digital images using AutoCAD / 中国基层医药

Objective To evaluate intra-and interobserver reliability of analysis of lower limb alignment on DR digital images using AutoCAD.Methods Angles on AP view and long leg view were measured three times by two trained observers separately using these two methods in 140 knees.The intra-and interobserver intraclass correlation coefficients with 95% CIs of two methods were calculated and compared with Fisher z transformation and Z test.Paired t test was used in comparing time consumption.Results For AutoCAD method,inter ICCs were 0.942? 0.993 ,intra ICCs were 0.937～0.999.For X-ray films method,inter ICCs were 0.736～0.981,intra ICCs were 0.759～0.951.Corresponding ICCs of AutoCAD method were higher than those of X-ray films method,most of which had significant differences(P<0.01).The consuming time of two observers in measuring one knee using AutoCAD method was 89.6 seconds and 94.3 seconds shorter than those using X-ray films method respectively.Both had significant differences(P<0.01).Conclusion It was a fast reliable method to assess lower limb alignment on DR digital images using AutoCAD.

Repeatability and Agreement of Macular Thickness Measurement Using Time and Spectral Domain OCT in Diabetic Macular Edema

PURPOSE: To evaluate the repeatability of macular thickness measurements using time domain (TD) OCT and spectral domain (SD) OCT in diabetic macular edema. METHODS: In 42 eyes of 42 patients with diabetic macular edema, three consecutive macular measurements were performed with TD OCT and SD OCT, and measurements for macular thickness and total macular volume obtained by the two OCTs were compared. The within-subject standard deviation (Sw), coefficient of variation (CVw), and intraclass correlation coefficient (ICC) were calculated to assess repeatability, with agreement between measurements assessed with Bland Altman plots. The correlations were also evaluated via the Pearson's correlation coefficient. RESULTS: The Sw of TD OCT and SD OCT for foveal thickness, total macular volume were 29.67 micrometer/16.44 micrometer, 1.26 mm3/0.23 mm3, respectively, and were significantly lower in SD OCT. The ranges of the respective CVw and ICC values were 1.10-2.78%, 0.78~0.96 for TD OCT, and 0.29~0.94%, 0.92~0.99 for SD OCT. The SD OCT showed better repeatability for macular thickness measurements (all p< or =0.001). The 95% limits of agreement for foveal and total macular volume were 88.9 micrometer, 2.4 mm3, respectively. The Pearson's correlation coefficients of macular thickness and total macular volume between the two OCT methods were statistically significant (p=0.88-0.99). CONCLUSIONS: Although both OCTs proved reliable for macular thickness measurements in diabetic macular edema, SD OCT shows better repeatability than TD OCT. Although macular thickness measurements obtained from the two OCTs cannot be used interchangeably, there were statistically significant correlations between measurements obtained using the two OCTs.

Repeatability and Agreement of Macular Thickness Measurement Using Time Domain OCT and Spectral Domain OCT in Normal Subjects

PURPOSE:To compare the repeatability and agreement of macular thickness measurements using time domain (TD) optical coherence tomography (OCT) and spectral domain (SD) OCT in normal subjects. METHODS: Thirty-four normal subjects were included. Three consecutive macular measurements were taken with TD OCT and SD OCT. Total and regional macular thickness and total macular volume obtained by the two OCTs were compared. Within-subject standard deviation (Sw), coefficient of variation (CVw), and the intraclass correlation coefficient (ICC) were calculated to evaluate repeatability. The agreement was examined with Bland Altman plots. The correlation was also evaluated with Pearson correlation coefficients and multiple regression analysis. RESULTS: Sw for foveal thickness, total macular thickness, and total macular volume were 11.53 microm, 7.58 microm, and 0.48 mm3 for TD OCT and 6.69 microm, 2.55 microm, and 0.09 mm3 for SD OCT, respectively. The values for SD OCT were consistently lower, and this result was statistically significant. The range of the respective CVw and ICC values were 1.10~2.78% and 0.78~0.96% for TD OCT, and 0.29~0.94% and 0.92~0.99% for SD OCT, respectively. The SD OCT showed better repeatability for macular thickness measurements(all with p< or =0.001). The spans of 95% limits of agreement for foveal thickness, total macular thickness, and total macular volume were 67.94 microm, 29.01 microm, and 0.98 mm3, respectively. The Pearson correlation coefficient of foveal thickness, total macular thickness, and total macular volume between the two OCT's was statistically significant. CONCLUSIONS: Although both OCTs are reliable for macular thickness measurements, SD OCT shows better repeatability compared with TD OCT. Although macular thickness measurements obtained from the two OCTs can not be used interchangeably due to low agreement by different standards of measurement, there was a statistically significant correlation between the two OCT's.

Comparison of Batch Assay and Random Assay Using Automatic Dispenser in Radioimmunoassay / 핵의학분자영상

PURPOSE: Radioimmunoassay (RIA) was usually performed by the batch assay. To improve the efficiency of RIA without increase of the cost and time, random assay could be a choice. We investigated the possibility of the random assay using automatic dispenser by assessing the agreement between batch assay and random assay. MATERIALS AND METHODS: The experiments were performed with four items; Triiodothyronine (T3), free thyroxine (fT4), Prostate specific antigen (PSA), Carcinoembryonic antigen (CEA). In each item, the sera of twenty patients, the standard, and the control samples were used. The measurements were done 4 times with 3 hour time intervals by random assay and batch assay. The coefficient of variation (CV) of the standard samples and patients' data in T3, fT4, PSA, and CEA were assessed. ICC (Intraclass correlation coefficient) and coefficient of correlation were measured to assessing the agreement between two methods. RESULTS: The CVs (%) of T3, fT4, PSA, and CEA measured by batch assay were 3.2+/-1.7%, 3.9+/-2.1%, 7.1+/-6.2%, 11.2+/-7.2%. The CVs by random assay were 2.1+/-1.7%, 4.8+/-3.1%, 3.6+/-4.8%, and 7.4+/-6.2%. The ICC between the batch assay and random assay were 0.9968 (T3), 0.9973 (fT4), 0.9996 (PSA), and 0.9901 (CEA). The coefficient of correlation between the batch assay and random assay were 0.9924(T3), 0.9974 (fT4), 0.9994 (PSA), and 0.9989 (CEA) (p<0.05). CONCLUSION: The results of random assay showed strong agreement with the batch assay in a day. These results suggest that random assay using automatic dispenser could be used in radioimmunoassay.

Variabilidade na aferição de medidas antropométricas: comparação de dois métodos estatísticos para avaliar a calibração de entrevistadores / Variability in the measurement of anthropometric measures: comparison between two statistical methods to assess interviewers, calibration

Estudos que incluem medidas antropométricas exigem, além da padronização de técnicas de aferição, o emprego de métodos estatísticos para a avaliação de erros de mensuração. OBJETIVO: Comparar duas técnicas estatísticas para avaliar a calibração de entrevistadores, em treinamento para a aferição de medidas antropométricas. METODOLOGIA: Treze entrevistadores participaram da fase de treinamento, que foi programado de modo que, em cada sessão, sub-grupos de entrevistadores realizassem duas aferições de medidas de peso e duas de altura em voluntários (em média, 10 voluntários/sessão). Ao todo, foram realizadas seis sessões para a aferição das medidas de peso e onze para a aferição das medidas de altura. Para as medidas de peso foram utilizadas balanças eletrônicas e, para as de altura, estadiômetros de parede. Para avaliar a calibração, dois métodos estatísticos foram comparados: a) o coeficiente de correlação intraclasse (CCI) e b) a precisão e a exatidão das aferições, segundo Habicht. RESULTADOS: Os entrevistadores foram submetidos, em média, a duas sessões para a calibração das medidas de peso e a três sessões para a calibração das medidas de altura, sendo a precisão atingida antes da exatidão. Os valores dos respectivos CCIs indicaram medições fortemente concordantes desde a primeira sessão. CONCLUSÃO: O método de Habicht apresentou melhor desempenho que o CCI, pois, além do cálculo da precisão, indicou a magnitude da divergência das aferições realizadas pelos entrevistadores, em relação às do supervisor (exatidão).