validated correlation coefficient: Topics by Science.gov

Sample records for validated correlation coefficient

What to Do With "Moderate" Reliability and Validity Coefficients?

PubMed

Post, Marcel W

2016-07-01

Clinimetric studies may use criteria for test-retest reliability and convergent validity such that correlation coefficients as low as .40 are supportive of reliability and validity. It can be argued that moderate (.40-.60) correlations should not be interpreted in this way and that reliability coefficients <.70 should be considered as indicative of unreliability. Convergent validity coefficients in the .40 to .60 or .40 to .70 range should be considered as indications of validity problems, or as inconclusive at best. Studies on reliability and convergent should be designed in such a way that it is realistic to expect high reliability and validity coefficients. Multitrait multimethod approaches are preferred to study construct (convergent-divergent) validity. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Tests of Hypotheses Arising In the Correlated Random Coefficient Model*

PubMed Central

Heckman, James J.; Schmierer, Daniel

2010-01-01

This paper examines the correlated random coefficient model. It extends the analysis of Swamy (1971), who pioneered the uncorrelated random coefficient model in economics. We develop the properties of the correlated random coefficient model and derive a new representation of the variance of the instrumental variable estimator for that model. We develop tests of the validity of the correlated random coefficient model against the null hypothesis of the uncorrelated random coefficient model. PMID:21170148
Real external predictivity of QSAR models: how to evaluate it? Comparison of different validation criteria and proposal of using the concordance correlation coefficient.

PubMed

Chirico, Nicola; Gramatica, Paola

2011-09-26

The main utility of QSAR models is their ability to predict activities/properties for new chemicals, and this external prediction ability is evaluated by means of various validation criteria. As a measure for such evaluation the OECD guidelines have proposed the predictive squared correlation coefficient Q(2)(F1) (Shi et al.). However, other validation criteria have been proposed by other authors: the Golbraikh-Tropsha method, r(2)(m) (Roy), Q(2)(F2) (Schüürmann et al.), Q(2)(F3) (Consonni et al.). In QSAR studies these measures are usually in accordance, though this is not always the case, thus doubts can arise when contradictory results are obtained. It is likely that none of the aforementioned criteria is the best in every situation, so a comparative study using simulated data sets is proposed here, using threshold values suggested by the proponents or those widely used in QSAR modeling. In addition, a different and simple external validation measure, the concordance correlation coefficient (CCC), is proposed and compared with other criteria. Huge data sets were used to study the general behavior of validation measures, and the concordance correlation coefficient was shown to be the most restrictive. On using simulated data sets of a more realistic size, it was found that CCC was broadly in agreement, about 96% of the time, with other validation measures in accepting models as predictive, and in almost all the examples it was the most precautionary. The proposed concordance correlation coefficient also works well on real data sets, where it seems to be more stable, and helps in making decisions when the validation measures are in conflict. Since it is conceptually simple, and given its stability and restrictiveness, we propose the concordance correlation coefficient as a complementary, or alternative, more prudent measure of a QSAR model to be externally predictive.
Clustering Coefficients for Correlation Networks.

PubMed

Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu

2018-01-01

Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly
Clustering Coefficients for Correlation Networks

PubMed Central

Masuda, Naoki; Sakaki, Michiko; Ezaki, Takahiro; Watanabe, Takamitsu

2018-01-01

Graph theory is a useful tool for deciphering structural and functional networks of the brain on various spatial and temporal scales. The clustering coefficient quantifies the abundance of connected triangles in a network and is a major descriptive statistics of networks. For example, it finds an application in the assessment of small-worldness of brain networks, which is affected by attentional and cognitive conditions, age, psychiatric disorders and so forth. However, it remains unclear how the clustering coefficient should be measured in a correlation-based network, which is among major representations of brain networks. In the present article, we propose clustering coefficients tailored to correlation matrices. The key idea is to use three-way partial correlation or partial mutual information to measure the strength of the association between the two neighboring nodes of a focal node relative to the amount of pseudo-correlation expected from indirect paths between the nodes. Our method avoids the difficulties of previous applications of clustering coefficient (and other) measures in defining correlational networks, i.e., thresholding on the correlation value, discarding of negative correlation values, the pseudo-correlation problem and full partial correlation matrices whose estimation is computationally difficult. For proof of concept, we apply the proposed clustering coefficient measures to functional magnetic resonance imaging data obtained from healthy participants of various ages and compare them with conventional clustering coefficients. We show that the clustering coefficients decline with the age. The proposed clustering coefficients are more strongly correlated with age than the conventional ones are. We also show that the local variants of the proposed clustering coefficients (i.e., abundance of triangles around a focal node) are useful in characterizing individual nodes. In contrast, the conventional local clustering coefficients were strongly
Estimation of the simple correlation coefficient.

PubMed

Shieh, Gwowen

2010-11-01

This article investigates some unfamiliar properties of the Pearson product-moment correlation coefficient for the estimation of simple correlation coefficient. Although Pearson's r is biased, except for limited situations, and the minimum variance unbiased estimator has been proposed in the literature, researchers routinely employ the sample correlation coefficient in their practical applications, because of its simplicity and popularity. In order to support such practice, this study examines the mean squared errors of r and several prominent formulas. The results reveal specific situations in which the sample correlation coefficient performs better than the unbiased and nearly unbiased estimators, facilitating recommendation of r as an effect size index for the strength of linear association between two variables. In addition, related issues of estimating the squared simple correlation coefficient are also considered.
Identifying presence of correlated errors in GRACE monthly harmonic coefficients using machine learning algorithms

NASA Astrophysics Data System (ADS)

Piretzidis, Dimitrios; Sra, Gurveer; Karantaidis, George; Sideris, Michael G.

2017-04-01

A new method for identifying correlated errors in Gravity Recovery and Climate Experiment (GRACE) monthly harmonic coefficients has been developed and tested. Correlated errors are present in the differences between monthly GRACE solutions, and can be suppressed using a de-correlation filter. In principle, the de-correlation filter should be implemented only on coefficient series with correlated errors to avoid losing useful geophysical information. In previous studies, two main methods of implementing the de-correlation filter have been utilized. In the first one, the de-correlation filter is implemented starting from a specific minimum order until the maximum order of the monthly solution examined. In the second one, the de-correlation filter is implemented only on specific coefficient series, the selection of which is based on statistical testing. The method proposed in the present study exploits the capabilities of supervised machine learning algorithms such as neural networks and support vector machines (SVMs). The pattern of correlated errors can be described by several numerical and geometric features of the harmonic coefficient series. The features of extreme cases of both correlated and uncorrelated coefficients are extracted and used for the training of the machine learning algorithms. The trained machine learning algorithms are later used to identify correlated errors and provide the probability of a coefficient series to be correlated. Regarding SVMs algorithms, an extensive study is performed with various kernel functions in order to find the optimal training model for prediction. The selection of the optimal training model is based on the classification accuracy of the trained SVM algorithm on the same samples used for training. Results show excellent performance of all algorithms with a classification accuracy of 97% - 100% on a pre-selected set of training samples, both in the validation stage of the training procedure and in the subsequent use of
Quantifying colocalization by correlation: the Pearson correlation coefficient is superior to the Mander's overlap coefficient.

PubMed

Adler, Jeremy; Parmryd, Ingela

2010-08-01

The Pearson correlation coefficient (PCC) and the Mander's overlap coefficient (MOC) are used to quantify the degree of colocalization between fluorophores. The MOC was introduced to overcome perceived problems with the PCC. The two coefficients are mathematically similar, differing in the use of either the absolute intensities (MOC) or of the deviation from the mean (PCC). A range of correlated datasets, which extend to the limits of the PCC, only evoked a limited response from the MOC. The PCC is unaffected by changes to the offset while the MOC increases when the offset is positive. Both coefficients are independent of gain. The MOC is a confusing hybrid measurement, that combines correlation with a heavily weighted form of co-occurrence, favors high intensity combinations, downplays combinations in which either or both intensities are low and ignores blank pixels. The PCC only measures correlation. A surprising finding was that the addition of a second uncorrelated population can substantially increase the measured correlation, demonstrating the importance of excluding background pixels. Overall, since the MOC is unresponsive to substantial changes in the data and is hard to interpret, it is neither an alternative to nor a useful substitute for the PCC. The MOC is not suitable for making measurements of colocalization either by correlation or co-occurrence.
Identification of Correlated GRACE Monthly Harmonic Coefficients Using Pattern Recognition and Neural Networks

NASA Astrophysics Data System (ADS)

Piretzidis, D.; Sra, G.; Sideris, M. G.

2016-12-01

This study explores new methods for identifying correlation errors in harmonic coefficients derived from monthly solutions of the Gravity Recovery and Climate Experiment (GRACE) satellite mission using pattern recognition and neural network algorithms. These correlation errors are evidenced in the differences between monthly solutions and can be suppressed using a de-correlation filter. In all studies so far, the implementation of the de-correlation filter starts from a specific minimum order (i.e., 11 for RL04 and 38 for RL05) until the maximum order of the monthly solution examined. This implementation method has two disadvantages, namely, the omission of filtering correlated coefficients of order less than the minimum order and the filtering of uncorrelated coefficients of order higher than the minimum order. In the first case, the filtered solution is not completely free of correlated errors, whereas the second case results in a monthly solution that suffers from loss of geophysical signal. In the present study, a new method of implementing the de-correlation filter is suggested, by identifying and filtering only the coefficients that show indications of high correlation. Several numerical and geometric properties of the harmonic coefficient series of all orders are examined. Extreme cases of both correlated and uncorrelated coefficients are selected, and their corresponding properties are used to train a two-layer feed-forward neural network. The objective of the neural network is to identify and quantify the correlation by providing the probability of an order of coefficients to be correlated. Results show good performance of the neural network, both in the validation stage of the training procedure and in the subsequent use of the trained network to classify independent coefficients. The neural network is also capable of identifying correlated coefficients even when a small number of training samples and neurons are used (e.g.,100 and 10, respectively).
Correlation Coefficients: Appropriate Use and Interpretation.

PubMed

Schober, Patrick; Boer, Christa; Schwarte, Lothar A

2018-05-01

Correlation in the broadest sense is a measure of an association between variables. In correlated data, the change in the magnitude of 1 variable is associated with a change in the magnitude of another variable, either in the same (positive correlation) or in the opposite (negative correlation) direction. Most often, the term correlation is used in the context of a linear relationship between 2 continuous variables and expressed as Pearson product-moment correlation. The Pearson correlation coefficient is typically used for jointly normally distributed data (data that follow a bivariate normal distribution). For nonnormally distributed continuous data, for ordinal data, or for data with relevant outliers, a Spearman rank correlation can be used as a measure of a monotonic association. Both correlation coefficients are scaled such that they range from -1 to +1, where 0 indicates that there is no linear or monotonic association, and the relationship gets stronger and ultimately approaches a straight line (Pearson correlation) or a constantly increasing or decreasing curve (Spearman correlation) as the coefficient approaches an absolute value of 1. Hypothesis tests and confidence intervals can be used to address the statistical significance of the results and to estimate the strength of the relationship in the population from which the data were sampled. The aim of this tutorial is to guide researchers and clinicians in the appropriate use and interpretation of correlation coefficients.
Feature Genes Selection Using Supervised Locally Linear Embedding and Correlation Coefficient for Microarray Classification

PubMed Central

Wang, Yun; Huang, Fangzhou

2018-01-01

The selection of feature genes with high recognition ability from the gene expression profiles has gained great significance in biology. However, most of the existing methods have a high time complexity and poor classification performance. Motivated by this, an effective feature selection method, called supervised locally linear embedding and Spearman's rank correlation coefficient (SLLE-SC2), is proposed which is based on the concept of locally linear embedding and correlation coefficient algorithms. Supervised locally linear embedding takes into account class label information and improves the classification performance. Furthermore, Spearman's rank correlation coefficient is used to remove the coexpression genes. The experiment results obtained on four public tumor microarray datasets illustrate that our method is valid and feasible. PMID:29666661
Feature Genes Selection Using Supervised Locally Linear Embedding and Correlation Coefficient for Microarray Classification.

PubMed

Xu, Jiucheng; Mu, Huiyu; Wang, Yun; Huang, Fangzhou

2018-01-01

The selection of feature genes with high recognition ability from the gene expression profiles has gained great significance in biology. However, most of the existing methods have a high time complexity and poor classification performance. Motivated by this, an effective feature selection method, called supervised locally linear embedding and Spearman's rank correlation coefficient (SLLE-SC 2 ), is proposed which is based on the concept of locally linear embedding and correlation coefficient algorithms. Supervised locally linear embedding takes into account class label information and improves the classification performance. Furthermore, Spearman's rank correlation coefficient is used to remove the coexpression genes. The experiment results obtained on four public tumor microarray datasets illustrate that our method is valid and feasible.
Random matrix theory analysis of cross-correlations in the US stock market: Evidence from Pearson’s correlation coefficient and detrended cross-correlation coefficient

NASA Astrophysics Data System (ADS)

Wang, Gang-Jin; Xie, Chi; Chen, Shou; Yang, Jiao-Jiao; Yang, Ming-Yan

2013-09-01

In this study, we first build two empirical cross-correlation matrices in the US stock market by two different methods, namely the Pearson’s correlation coefficient and the detrended cross-correlation coefficient (DCCA coefficient). Then, combining the two matrices with the method of random matrix theory (RMT), we mainly investigate the statistical properties of cross-correlations in the US stock market. We choose the daily closing prices of 462 constituent stocks of S&P 500 index as the research objects and select the sample data from January 3, 2005 to August 31, 2012. In the empirical analysis, we examine the statistical properties of cross-correlation coefficients, the distribution of eigenvalues, the distribution of eigenvector components, and the inverse participation ratio. From the two methods, we find some new results of the cross-correlations in the US stock market in our study, which are different from the conclusions reached by previous studies. The empirical cross-correlation matrices constructed by the DCCA coefficient show several interesting properties at different time scales in the US stock market, which are useful to the risk management and optimal portfolio selection, especially to the diversity of the asset portfolio. It will be an interesting and meaningful work to find the theoretical eigenvalue distribution of a completely random matrix R for the DCCA coefficient because it does not obey the Marčenko-Pastur distribution.
Temporal correlation coefficient for directed networks.

PubMed

Büttner, Kathrin; Salau, Jennifer; Krieter, Joachim

2016-01-01

Previous studies dealing with network theory focused mainly on the static aggregation of edges over specific time window lengths. Thus, most of the dynamic information gets lost. To assess the quality of such a static aggregation the temporal correlation coefficient can be calculated. It measures the overall possibility for an edge to persist between two consecutive snapshots. Up to now, this measure is only defined for undirected networks. Therefore, we introduce the adaption of the temporal correlation coefficient to directed networks. This new methodology enables the distinction between ingoing and outgoing edges. Besides a small example network presenting the single calculation steps, we also calculated the proposed measurements for a real pig trade network to emphasize the importance of considering the edge direction. The farm types at the beginning of the pork supply chain showed clearly higher values for the outgoing temporal correlation coefficient compared to the farm types at the end of the pork supply chain. These farm types showed higher values for the ingoing temporal correlation coefficient. The temporal correlation coefficient is a valuable tool to understand the structural dynamics of these systems, as it assesses the consistency of the edge configuration. The adaption of this measure for directed networks may help to preserve meaningful additional information about the investigated network that might get lost if the edge directions are ignored.
Modified Regression Correlation Coefficient for Poisson Regression Model

NASA Astrophysics Data System (ADS)

Kaengthong, Nattacha; Domthong, Uthumporn

2017-09-01

This study gives attention to indicators in predictive power of the Generalized Linear Model (GLM) which are widely used; however, often having some restrictions. We are interested in regression correlation coefficient for a Poisson regression model. This is a measure of predictive power, and defined by the relationship between the dependent variable (Y) and the expected value of the dependent variable given the independent variables [E(Y|X)] for the Poisson regression model. The dependent variable is distributed as Poisson. The purpose of this research was modifying regression correlation coefficient for Poisson regression model. We also compare the proposed modified regression correlation coefficient with the traditional regression correlation coefficient in the case of two or more independent variables, and having multicollinearity in independent variables. The result shows that the proposed regression correlation coefficient is better than the traditional regression correlation coefficient based on Bias and the Root Mean Square Error (RMSE).
A new correlation coefficient for bivariate time-series data

NASA Astrophysics Data System (ADS)

Erdem, Orhan; Ceyhan, Elvan; Varli, Yusuf

2014-11-01

The correlation in time series has received considerable attention in the literature. Its use has attained an important role in the social sciences and finance. For example, pair trading in finance is concerned with the correlation between stock prices, returns, etc. In general, Pearson’s correlation coefficient is employed in these areas although it has many underlying assumptions which restrict its use. Here, we introduce a new correlation coefficient which takes into account the lag difference of data points. We investigate the properties of this new correlation coefficient. We demonstrate that it is more appropriate for showing the direction of the covariation of the two variables over time. We also compare the performance of the new correlation coefficient with Pearson’s correlation coefficient and Detrended Cross-Correlation Analysis (DCCA) via simulated examples.
A short note on jackknifing the concordance correlation coefficient.

PubMed

Feng, Dai; Baumgartner, Richard; Svetnik, Vladimir

2014-02-10

Lin's concordance correlation coefficient (CCC) is a very popular scaled index of agreement used in applied statistics. To obtain a confidence interval (CI) for the estimate of CCC, jackknifing was proposed and shown to perform well in simulation as well as in applications. However, a theoretical proof of the validity of the jackknife CI for the CCC has not been presented yet. In this note, we establish a sufficient condition for using the jackknife method to construct the CI for the CCC. Copyright © 2013 John Wiley & Sons, Ltd.
Correlation coefficient based supervised locally linear embedding for pulmonary nodule recognition.

PubMed

Wu, Panpan; Xia, Kewen; Yu, Hengyong

2016-11-01

Dimensionality reduction techniques are developed to suppress the negative effects of high dimensional feature space of lung CT images on classification performance in computer aided detection (CAD) systems for pulmonary nodule detection. An improved supervised locally linear embedding (SLLE) algorithm is proposed based on the concept of correlation coefficient. The Spearman's rank correlation coefficient is introduced to adjust the distance metric in the SLLE algorithm to ensure that more suitable neighborhood points could be identified, and thus to enhance the discriminating power of embedded data. The proposed Spearman's rank correlation coefficient based SLLE (SC(2)SLLE) is implemented and validated in our pilot CAD system using a clinical dataset collected from the publicly available lung image database consortium and image database resource initiative (LICD-IDRI). Particularly, a representative CAD system for solitary pulmonary nodule detection is designed and implemented. After a sequential medical image processing steps, 64 nodules and 140 non-nodules are extracted, and 34 representative features are calculated. The SC(2)SLLE, as well as SLLE and LLE algorithm, are applied to reduce the dimensionality. Several quantitative measurements are also used to evaluate and compare the performances. Using a 5-fold cross-validation methodology, the proposed algorithm achieves 87.65% accuracy, 79.23% sensitivity, 91.43% specificity, and 8.57% false positive rate, on average. Experimental results indicate that the proposed algorithm outperforms the original locally linear embedding and SLLE coupled with the support vector machine (SVM) classifier. Based on the preliminary results from a limited number of nodules in our dataset, this study demonstrates the great potential to improve the performance of a CAD system for nodule detection using the proposed SC(2)SLLE. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
[Electroencephalogram Feature Selection Based on Correlation Coefficient Analysis].

PubMed

Zhou, Jinzhi; Tang, Xiaofang

2015-08-01

In order to improve the accuracy of classification with small amount of motor imagery training data on the development of brain-computer interface (BCD systems, we proposed an analyzing method to automatically select the characteristic parameters based on correlation coefficient analysis. Throughout the five sample data of dataset IV a from 2005 BCI Competition, we utilized short-time Fourier transform (STFT) and correlation coefficient calculation to reduce the number of primitive electroencephalogram dimension, then introduced feature extraction based on common spatial pattern (CSP) and classified by linear discriminant analysis (LDA). Simulation results showed that the average rate of classification accuracy could be improved by using correlation coefficient feature selection method than those without using this algorithm. Comparing with support vector machine (SVM) optimization features algorithm, the correlation coefficient analysis can lead better selection parameters to improve the accuracy of classification.
The Attenuation of Correlation Coefficients: A Statistical Literacy Issue

ERIC Educational Resources Information Center

Trafimow, David

2016-01-01

Much of the science reported in the media depends on correlation coefficients. But the size of correlation coefficients depends, in part, on the reliability with which the correlated variables are measured. Understanding this is a statistical literacy issue.

Similarity analysis between chromosomes of Homo sapiens and monkeys with correlation coefficient, rank correlation coefficient and cosine similarity measures

PubMed Central

Someswara Rao, Chinta; Viswanadha Raju, S.

2016-01-01

In this paper, we consider correlation coefficient, rank correlation coefficient and cosine similarity measures for evaluating similarity between Homo sapiens and monkeys. We used DNA chromosomes of genome wide genes to determine the correlation between the chromosomal content and evolutionary relationship. The similarity among the H. sapiens and monkeys is measured for a total of 210 chromosomes related to 10 species. The similarity measures of these different species show the relationship between the H. sapiens and monkey. This similarity will be helpful at theft identification, maternity identification, disease identification, etc. PMID:26981409
Similarity analysis between chromosomes of Homo sapiens and monkeys with correlation coefficient, rank correlation coefficient and cosine similarity measures.

PubMed

Someswara Rao, Chinta; Viswanadha Raju, S

2016-03-01

In this paper, we consider correlation coefficient, rank correlation coefficient and cosine similarity measures for evaluating similarity between Homo sapiens and monkeys. We used DNA chromosomes of genome wide genes to determine the correlation between the chromosomal content and evolutionary relationship. The similarity among the H. sapiens and monkeys is measured for a total of 210 chromosomes related to 10 species. The similarity measures of these different species show the relationship between the H. sapiens and monkey. This similarity will be helpful at theft identification, maternity identification, disease identification, etc.
Genome-scale cluster analysis of replicated microarrays using shrinkage correlation coefficient.

PubMed

Yao, Jianchao; Chang, Chunqi; Salmi, Mari L; Hung, Yeung Sam; Loraine, Ann; Roux, Stanley J

2008-06-18

Currently, clustering with some form of correlation coefficient as the gene similarity metric has become a popular method for profiling genomic data. The Pearson correlation coefficient and the standard deviation (SD)-weighted correlation coefficient are the two most widely-used correlations as the similarity metrics in clustering microarray data. However, these two correlations are not optimal for analyzing replicated microarray data generated by most laboratories. An effective correlation coefficient is needed to provide statistically sufficient analysis of replicated microarray data. In this study, we describe a novel correlation coefficient, shrinkage correlation coefficient (SCC), that fully exploits the similarity between the replicated microarray experimental samples. The methodology considers both the number of replicates and the variance within each experimental group in clustering expression data, and provides a robust statistical estimation of the error of replicated microarray data. The value of SCC is revealed by its comparison with two other correlation coefficients that are currently the most widely-used (Pearson correlation coefficient and SD-weighted correlation coefficient) using statistical measures on both synthetic expression data as well as real gene expression data from Saccharomyces cerevisiae. Two leading clustering methods, hierarchical and k-means clustering were applied for the comparison. The comparison indicated that using SCC achieves better clustering performance. Applying SCC-based hierarchical clustering to the replicated microarray data obtained from germinating spores of the fern Ceratopteris richardii, we discovered two clusters of genes with shared expression patterns during spore germination. Functional analysis suggested that some of the genetic mechanisms that control germination in such diverse plant lineages as mosses and angiosperms are also conserved among ferns. This study shows that SCC is an alternative to the Pearson
Statistical Study of Turbulence: Spectral Functions and Correlation Coefficients

NASA Technical Reports Server (NTRS)

Frenkiel, Francois N.

1958-01-01

In reading the publications on turbulence of different authors, one often runs the risk of confusing the various correlation coefficients and turbulence spectra. We have made a point of defining, by appropriate concepts, the differences which exist between these functions. Besides, we introduce in the symbols a few new characteristics of turbulence. In the first chapter, we study some relations between the correlation coefficients and the different turbulence spectra. Certain relations are given by means of demonstrations which could be called intuitive rather than mathematical. In this way we demonstrate that the correlation coefficients between the simultaneous turbulent velocities at two points are identical, whether studied in Lagrange's or in Euler's systems. We then consider new spectra of turbulence, obtained by study of the simultaneous velocities along a straight line of given direction. We determine some relations between these spectra and the correlation coefficients. Examining the relation between the spectrum of the turbulence measured at a fixed point and the longitudinal-correlation curve given by G. I. Taylor, we find that this equation is exact only when the coefficient is very small.
Factors That Attenuate the Correlation Coefficient and Its Analogs.

ERIC Educational Resources Information Center

Dolenz, Beverly

The correlation coefficient is an integral part of many other statistical techniques (analysis of variance, t-tests, etc.), since all analytic methods are actually correlational (G. V. Glass and K. D. Hopkins, 1984). The correlation coefficient is a statistical summary that represents the degree and direction of relationship between two variables.…
Limits of the memory coefficient in measuring correlated bursts

NASA Astrophysics Data System (ADS)

Jo, Hang-Hyun; Hiraoka, Takayuki

2018-03-01

Temporal inhomogeneities in event sequences of natural and social phenomena have been characterized in terms of interevent times and correlations between interevent times. The inhomogeneities of interevent times have been extensively studied, while the correlations between interevent times, often called correlated bursts, are far from being fully understood. For measuring the correlated bursts, two relevant approaches were suggested, i.e., memory coefficient and burst size distribution. Here a burst size denotes the number of events in a bursty train detected for a given time window. Empirical analyses have revealed that the larger memory coefficient tends to be associated with the heavier tail of the burst size distribution. In particular, empirical findings in human activities appear inconsistent, such that the memory coefficient is close to 0, while burst size distributions follow a power law. In order to comprehend these observations, by assuming the conditional independence between consecutive interevent times, we derive the analytical form of the memory coefficient as a function of parameters describing interevent time and burst size distributions. Our analytical result can explain the general tendency of the larger memory coefficient being associated with the heavier tail of burst size distribution. We also find that the apparently inconsistent observations in human activities are compatible with each other, indicating that the memory coefficient has limits to measure the correlated bursts.
Dynamics analysis of SIR epidemic model with correlation coefficients and clustering coefficient in networks.

PubMed

Zhang, Juping; Yang, Chan; Jin, Zhen; Li, Jia

2018-07-14

In this paper, the correlation coefficients between nodes in states are used as dynamic variables, and we construct SIR epidemic dynamic models with correlation coefficients by using the pair approximation method in static networks and dynamic networks, respectively. Considering the clustering coefficient of the network, we analytically investigate the existence and the local asymptotic stability of each equilibrium of these models and derive threshold values for the prevalence of diseases. Additionally, we obtain two equivalent epidemic thresholds in dynamic networks, which are compared with the results of the mean field equations. Copyright © 2018 Elsevier Ltd. All rights reserved.
Ground reaction force analysed with correlation coefficient matrix in group of stroke patients.

PubMed

Szczerbik, Ewa; Krawczyk, Maciej; Syczewska, Małgorzata

2014-01-01

Stroke is the third cause of death in contemporary society and causes many disorders. Clinical scales, ground reaction force (GRF) and objective gait analysis are used for assessment of patient's rehabilitation progress during treatment. The goal of this paper is to assess whether signal correlation coefficient matrix applied to GRF can be used for evaluation of the status of post-stroke patients. A group of patients underwent clinical assessment and instrumented gait analysis simultaneously three times. The difference between components of patient's GRF (vertical, fore/aft, med/lat) and normal ones (reference GRF of healthy subjects) was calculated as correlation coefficient. Patients were divided into two groups ("worse" and "better") based on the clinical functional scale tests done at the beginning of rehabilitation process. The results obtained by these two groups were compared using statistical analysis. An increase of median value of correlation coefficient is observed in all components of GRF, but only in non-paretic leg. Analysis of GRF signal can be helpful in assessment of post-stroke patients during rehabilitation. Improvement in stroke patients was observed in non-paretic leg of the "worse" group. GRF analysis should not be the only tool for objective validation of patient's improvement, but could be used as additional source of information.
Diagnosing cysts with correlation coefficient images from 2-dimensional freehand elastography.

PubMed

Booi, Rebecca C; Carson, Paul L; O'Donnell, Matthew; Richards, Michael S; Rubin, Jonathan M

2007-09-01

We compared the diagnostic potential of using correlation coefficient images versus elastograms from 2-dimensional (2D) freehand elastography to characterize breast cysts. In this preliminary study, which was approved by the Institutional Review Board and compliant with the Health Insurance Portability and Accountability Act, we imaged 4 consecutive human subjects (4 cysts, 1 biopsy-verified benign breast parenchyma) with freehand 2D elastography. Data were processed offline with conventional 2D phase-sensitive speckle-tracking algorithms. The correlation coefficient in the cyst and surrounding tissue was calculated, and appearances of the cysts in the correlation coefficient images and elastograms were compared. The correlation coefficient in the cysts was considerably lower (14%-37%) than in the surrounding tissue because of the lack of sufficient speckle in the cysts, as well as the prominence of random noise, reverberations, and clutter, which decorrelated quickly. Thus, the cysts were visible in all correlation coefficient images. In contrast, the elastograms associated with these cysts each had different elastographic patterns. The solid mass in this study did not have the same high decorrelation rate as the cysts, having a correlation coefficient only 2.1% lower than that of surrounding tissue. Correlation coefficient images may produce a more direct, reliable, and consistent method for characterizing cysts than elastograms.
Uses and Misuses of the Correlation Coefficient.

ERIC Educational Resources Information Center

Onwuegbuzie, Anthony J.; Daniel, Larry G.

The purpose of this paper is to provide an in-depth critical analysis of the use and misuse of correlation coefficients. Various analytical and interpretational misconceptions are reviewed, beginning with the egregious assumption that correlational statistics may be useful in inferring causality. Additional misconceptions, stemming from…
A robust bayesian estimate of the concordance correlation coefficient.

PubMed

Feng, Dai; Baumgartner, Richard; Svetnik, Vladimir

2015-01-01

A need for assessment of agreement arises in many situations including statistical biomarker qualification or assay or method validation. Concordance correlation coefficient (CCC) is one of the most popular scaled indices reported in evaluation of agreement. Robust methods for CCC estimation currently present an important statistical challenge. Here, we propose a novel Bayesian method of robust estimation of CCC based on multivariate Student's t-distribution and compare it with its alternatives. Furthermore, we extend the method to practically relevant settings, enabling incorporation of confounding covariates and replications. The superiority of the new approach is demonstrated using simulation as well as real datasets from biomarker application in electroencephalography (EEG). This biomarker is relevant in neuroscience for development of treatments for insomnia.
Supersymmetric contributions to weak decay correlation coefficients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Profumo, S.; Ramsey-Musolf, M. J.; Tulin, S.

2007-04-01

We study supersymmetric contributions to correlation coefficients that characterize the spectral shape and angular distribution for polarized {mu}- and {beta}-decays. In the minimal supersymmetric standard model (MSSM), one-loop box graphs containing superpartners can give rise to non-(V-Ax(V-A) four-fermion operators in the presence of left-right or flavor mixing between sfermions. We analyze the present phenomenological constraints on such mixing and determine the range of allowed contributions to the weak decay correlation coefficients. We discuss the prospective implications for future {mu}- and {beta}-decay experiments, and argue that they may provide unique probes of left-right mixing in the first generation scalar fermion sector.
Analytic posteriors for Pearson's correlation coefficient.

PubMed

Ly, Alexander; Marsman, Maarten; Wagenmakers, Eric-Jan

2018-02-01

Pearson's correlation is one of the most common measures of linear dependence. Recently, Bernardo (11th International Workshop on Objective Bayes Methodology, 2015) introduced a flexible class of priors to study this measure in a Bayesian setting. For this large class of priors, we show that the (marginal) posterior for Pearson's correlation coefficient and all of the posterior moments are analytic. Our results are available in the open-source software package JASP.
Systematic bias of correlation coefficient may explain negative accuracy of genomic prediction.

PubMed

Zhou, Yao; Vales, M Isabel; Wang, Aoxue; Zhang, Zhiwu

2017-09-01

Accuracy of genomic prediction is commonly calculated as the Pearson correlation coefficient between the predicted and observed phenotypes in the inference population by using cross-validation analysis. More frequently than expected, significant negative accuracies of genomic prediction have been reported in genomic selection studies. These negative values are surprising, given that the minimum value for prediction accuracy should hover around zero when randomly permuted data sets are analyzed. We reviewed the two common approaches for calculating the Pearson correlation and hypothesized that these negative accuracy values reflect potential bias owing to artifacts caused by the mathematical formulas used to calculate prediction accuracy. The first approach, Instant accuracy, calculates correlations for each fold and reports prediction accuracy as the mean of correlations across fold. The other approach, Hold accuracy, predicts all phenotypes in all fold and calculates correlation between the observed and predicted phenotypes at the end of the cross-validation process. Using simulated and real data, we demonstrated that our hypothesis is true. Both approaches are biased downward under certain conditions. The biases become larger when more fold are employed and when the expected accuracy is low. The bias of Instant accuracy can be corrected using a modified formula. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Meta-Analysis of the Correlation between Apparent Diffusion Coefficient and Standardized Uptake Value in Malignant Disease

PubMed Central

Deng, Shengming; Wu, Zhifang; Wu, Yiwei; Zhang, Wei; Li, Jihui; Dai, Na

2017-01-01

The objective of this meta-analysis is to explore the correlation between the apparent diffusion coefficient (ADC) on diffusion-weighted MR and the standard uptake value (SUV) of 18F-FDG on PET/CT in patients with cancer. Databases such as PubMed (MEDLINE included), EMBASE, and Cochrane Database of Systematic Review were searched for relevant original articles that explored the correlation between SUV and ADC in English. After applying Fisher's r-to-z transformation, correlation coefficient (r) values were extracted from each study and 95% confidence intervals (CIs) were calculated. Sensitivity and subgroup analyses based on tumor type were performed to investigate the potential heterogeneity. Forty-nine studies were eligible for the meta-analysis, comprising 1927 patients. Pooled r for all studies was −0.35 (95% CI: −0.42–0.28) and exhibited a notable heterogeneity (I2 = 78.4%; P < 0.01). In terms of the cancer type subgroup analysis, combined correlation coefficients of ADC/SUV range from −0.12 (lymphoma, n = 5) to −0.59 (pancreatic cancer, n = 2). We concluded that there is an average negative correlation between ADC and SUV in patients with cancer. Higher correlations were found in the brain tumor, cervix carcinoma, and pancreas cancer. However, a larger, prospective study is warranted to validate these findings in different cancer types. PMID:29097924
Meta-Analysis of the Correlation between Apparent Diffusion Coefficient and Standardized Uptake Value in Malignant Disease.

PubMed

Deng, Shengming; Wu, Zhifang; Wu, Yiwei; Zhang, Wei; Li, Jihui; Dai, Na; Zhang, Bin; Yan, Jianhua

2017-01-01

The objective of this meta-analysis is to explore the correlation between the apparent diffusion coefficient (ADC) on diffusion-weighted MR and the standard uptake value (SUV) of 18 F-FDG on PET/CT in patients with cancer. Databases such as PubMed (MEDLINE included), EMBASE, and Cochrane Database of Systematic Review were searched for relevant original articles that explored the correlation between SUV and ADC in English. After applying Fisher's r -to- z transformation, correlation coefficient ( r ) values were extracted from each study and 95% confidence intervals (CIs) were calculated. Sensitivity and subgroup analyses based on tumor type were performed to investigate the potential heterogeneity. Forty-nine studies were eligible for the meta-analysis, comprising 1927 patients. Pooled r for all studies was -0.35 (95% CI: -0.42-0.28) and exhibited a notable heterogeneity ( I 2 = 78.4%; P < 0.01). In terms of the cancer type subgroup analysis, combined correlation coefficients of ADC/SUV range from -0.12 (lymphoma, n = 5) to -0.59 (pancreatic cancer, n = 2). We concluded that there is an average negative correlation between ADC and SUV in patients with cancer. Higher correlations were found in the brain tumor, cervix carcinoma, and pancreas cancer. However, a larger, prospective study is warranted to validate these findings in different cancer types.
Testing the Difference of Correlated Agreement Coefficients for Statistical Significance

ERIC Educational Resources Information Center

Gwet, Kilem L.

2016-01-01

This article addresses the problem of testing the difference between two correlated agreement coefficients for statistical significance. A number of authors have proposed methods for testing the difference between two correlated kappa coefficients, which require either the use of resampling methods or the use of advanced statistical modeling…
The correlation between apparent diffusion coefficient and tumor cellularity in patients: a meta-analysis.

PubMed

Chen, Lihua; Liu, Min; Bao, Jing; Xia, Yunbao; Zhang, Jiuquan; Zhang, Lin; Huang, Xuequan; Wang, Jian

2013-01-01

To perform a meta-analysis exploring the correlation between the apparent diffusion coefficient (ADC) and tumor cellularity in patients. We searched medical and scientific literature databases for studies discussing the correlation between the ADC and tumor cellularity in patients. Only studies that were published in English or Chinese prior to November 2012 were considered for inclusion. Summary correlation coefficient (r) values were extracted from each study, and 95% confidence intervals (CIs) were calculated. Sensitivity and subgroup analyses were performed to investigate potential heterogeneity. Of 189 studies, 28 were included in the meta-analysis, comprising 729 patients. The pooled r for all studies was -0.57 (95% CI: -0.62, -0.52), indicating notable heterogeneity (P<0.001). After the sensitivity analysis, two studies were excluded, and the pooled r was -0.61 (95% CI: -0.66, -0.56) and was not significantly heterogeneous (P = 0.127). Regarding tumor type subgroup analysis, there were sufficient data to support a strong negative correlation between the ADC and cellularity for brain tumors. There was no notable evidence of publication bias. There is a strong negative correlation between the ADC and tumor cellularity in patients, particularly in the brain. However, larger, prospective studies are warranted to validate these findings in other cancer types.
Detecting PM2.5's Correlations between Neighboring Cities Using a Time-Lagged Cross-Correlation Coefficient.

PubMed

Wang, Fang; Wang, Lin; Chen, Yuming

2017-08-31

In order to investigate the time-dependent cross-correlations of fine particulate (PM2.5) series among neighboring cities in Northern China, in this paper, we propose a new cross-correlation coefficient, the time-lagged q-L dependent height crosscorrelation coefficient (denoted by p q (τ, L)), which incorporates the time-lag factor and the fluctuation amplitude information into the analogous height cross-correlation analysis coefficient. Numerical tests are performed to illustrate that the newly proposed coefficient ρ q (τ, L) can be used to detect cross-correlations between two series with time lags and to identify different range of fluctuations at which two series possess cross-correlations. Applying the new coefficient to analyze the time-dependent cross-correlations of PM2.5 series between Beijing and the three neighboring cities of Tianjin, Zhangjiakou, and Baoding, we find that time lags between the PM2.5 series with larger fluctuations are longer than those between PM2.5 series withsmaller fluctuations. Our analysis also shows that cross-correlations between the PM2.5 series of two neighboring cities are significant and the time lags between two PM2.5 series of neighboring cities are significantly non-zero. These findings providenew scientific support on the view that air pollution in neighboring cities can affect one another not simultaneously but with a time lag.
Correlation and prediction of gaseous diffusion coefficients.

NASA Technical Reports Server (NTRS)

Marrero, T. R.; Mason, E. A.

1973-01-01

A new correlation method for binary gaseous diffusion coefficients from very low temperatures to 10,000 K is proposed based on an extended principle of corresponding states, and having greater range and accuracy than previous correlations. There are two correlation parameters that are related to other physical quantities and that are predictable in the absence of diffusion measurements. Quantum effects and composition dependence are included, but high-pressure effects are not. The results are directly applicable to multicomponent mixtures.

The Evolution of Pearson's Correlation Coefficient

ERIC Educational Resources Information Center

Kader, Gary D.; Franklin, Christine A.

2008-01-01

This article describes an activity for developing the notion of association between two quantitative variables. By exploring a collection of scatter plots, the authors propose a nonstandard "intuitive" measure of association; and by examining properties of this measure, they develop the more standard measure, Pearson's Correlation Coefficient. The…
An efficient sensitivity analysis method for modified geometry of Macpherson suspension based on Pearson correlation coefficient

NASA Astrophysics Data System (ADS)

Shojaeefard, Mohammad Hasan; Khalkhali, Abolfazl; Yarmohammadisatri, Sadegh

2017-06-01

The main purpose of this paper is to propose a new method for designing Macpherson suspension, based on the Sobol indices in terms of Pearson correlation which determines the importance of each member on the behaviour of vehicle suspension. The formulation of dynamic analysis of Macpherson suspension system is developed using the suspension members as the modified links in order to achieve the desired kinematic behaviour. The mechanical system is replaced with an equivalent constrained links and then kinematic laws are utilised to obtain a new modified geometry of Macpherson suspension. The equivalent mechanism of Macpherson suspension increased the speed of analysis and reduced its complexity. The ADAMS/CAR software is utilised to simulate a full vehicle, Renault Logan car, in order to analyse the accuracy of modified geometry model. An experimental 4-poster test rig is considered for validating both ADAMS/CAR simulation and analytical geometry model. Pearson correlation coefficient is applied to analyse the sensitivity of each suspension member according to vehicle objective functions such as sprung mass acceleration, etc. Besides this matter, the estimation of Pearson correlation coefficient between variables is analysed in this method. It is understood that the Pearson correlation coefficient is an efficient method for analysing the vehicle suspension which leads to a better design of Macpherson suspension system.
Clustering stocks using partial correlation coefficients

NASA Astrophysics Data System (ADS)

Jung, Sean S.; Chang, Woojin

2016-11-01

A partial correlation analysis is performed on the Korean stock market (KOSPI). The difference between Pearson correlation and the partial correlation is analyzed and it is found that when conditioned on the market return, Pearson correlation coefficients are generally greater than those of the partial correlation, which implies that the market return tends to drive up the correlation between stock returns. A clustering analysis is then performed to study the market structure given by the partial correlation analysis and the members of the clusters are compared with the Global Industry Classification Standard (GICS). The initial hypothesis is that the firms in the same GICS sector are clustered together since they are in a similar business and environment. However, the result is inconsistent with the hypothesis and most clusters are a mix of multiple sectors suggesting that the traditional approach of using sectors to determine the proximity between stocks may not be sufficient enough to diversify a portfolio.
Zero Pearson coefficient for strongly correlated growing trees

NASA Astrophysics Data System (ADS)

Dorogovtsev, S. N.; Ferreira, A. L.; Goltsev, A. V.; Mendes, J. F. F.

2010-03-01

We obtained Pearson’s coefficient of strongly correlated recursive networks growing by preferential attachment of every new vertex by m edges. We found that the Pearson coefficient is exactly zero in the infinite network limit for the recursive trees (m=1) . If the number of connections of new vertices exceeds one (m>1) , then the Pearson coefficient in the infinite networks equals zero only when the degree distribution exponent γ does not exceed 4. We calculated the Pearson coefficient for finite networks and observed a slow power-law-like approach to an infinite network limit. Our findings indicate that Pearson’s coefficient strongly depends on size and details of networks, which makes this characteristic virtually useless for quantitative comparison of different networks.
Zero Pearson coefficient for strongly correlated growing trees.

PubMed

Dorogovtsev, S N; Ferreira, A L; Goltsev, A V; Mendes, J F F

2010-03-01

We obtained Pearson's coefficient of strongly correlated recursive networks growing by preferential attachment of every new vertex by m edges. We found that the Pearson coefficient is exactly zero in the infinite network limit for the recursive trees (m=1). If the number of connections of new vertices exceeds one (m>1), then the Pearson coefficient in the infinite networks equals zero only when the degree distribution exponent gamma does not exceed 4. We calculated the Pearson coefficient for finite networks and observed a slow power-law-like approach to an infinite network limit. Our findings indicate that Pearson's coefficient strongly depends on size and details of networks, which makes this characteristic virtually useless for quantitative comparison of different networks.
Correlation tests of the engine performance parameter by using the detrended cross-correlation coefficient

NASA Astrophysics Data System (ADS)

Dong, Keqiang; Gao, You; Jing, Liming

2015-02-01

The presence of cross-correlation in complex systems has long been noted and studied in a broad range of physical applications. We here focus on an aero-engine system as an example of a complex system. By applying the detrended cross-correlation (DCCA) coefficient method to aero-engine time series, we investigate the effects of the data length and the time scale on the detrended cross-correlation coefficients ρ DCCA ( T, s). We then show, for a twin-engine aircraft, that the engine fuel flow time series derived from the left engine and the right engine exhibit much stronger cross-correlations than the engine exhaust-gas temperature series derived from the left engine and the right engine do.
A comparison of two indices for the intraclass correlation coefficient.

PubMed

Shieh, Gwowen

2012-12-01

In the present study, we examined the behavior of two indices for measuring the intraclass correlation in the one-way random effects model: the prevailing ICC(1) (Fisher, 1938) and the corrected eta-squared (Bliese & Halverson, 1998). These two procedures differ both in their methods of estimating the variance components that define the intraclass correlation coefficient and in their performance of bias and mean squared error in the estimation of the intraclass correlation coefficient. In contrast with the natural unbiased principle used to construct ICC(1), in the present study it was analytically shown that the corrected eta-squared estimator is identical to the maximum likelihood estimator and the pairwise estimator under equal group sizes. Moreover, the empirical results obtained from the present Monte Carlo simulation study across various group structures revealed the mutual dominance relationship between their truncated versions for negative values. The corrected eta-squared estimator performs better than the ICC(1) estimator when the underlying population intraclass correlation coefficient is small. Conversely, ICC(1) has a clear advantage over the corrected eta-squared for medium and large magnitudes of population intraclass correlation coefficient. The conceptual description and numerical investigation provide guidelines to help researchers choose between the two indices for more accurate reliability analysis in multilevel research.
Evaluation of the Correlation Coefficient of Polyethylene Glycol Treated and Direct Prolactin Results and Comparability with Different Assay System Results.

PubMed

Pal, Shyamali

2017-12-01

The presence of Macro prolactin is a significant cause of elevated prolactin resulting in misdiagnosis in all automated systems. Poly ethylene glycol (PEG) pretreatment is the preventive process but such process includes the probability of loss of a fraction of bioactive prolactin. Surprisingly, PEG treated EQAS & IQAS samples in Cobas e 411 are found out to be correlating with direct results of at least 3 immunoassay systems and treated and untreated Cobas e 411 results are comparable by a correlation coefficient. Comparison of EQAS, IQAS and patient samples were done to find out the trueness of such correlation factor. Study with patient's results have established the correlation coefficient is valid for very small concentration of prolactin also. EQAS, IQAS and 150 patient samples were treated with PEG and prolactin results of treated and untreated samples obtained from Roche Cobas e 411. 25 patient's results (treated) were compared with direct results in Advia Centaur, Architect I & Access2 systems. Correlation coefficient was obtained from trend line of the treated and untreated results. Two tailed p-value obtained from regression coefficient(r) and sample size. The correlation coefficient is in the range (0.761-0.771). Reverse correlation range is (1.289-1.301). r value of two sets of calculated results were 0.995. Two tailed p- value is zero approving dismissal of null hypothesis. The z-score of EQAS does not always assure authenticity of resultsPEG precipitation is correlated by the factor 0.761 even in very small concentrationsAbbreviationsGFCgel filtration chromatographyPEGpolyethylene glycolEQASexternal quality assurance systemM-PRLmacro prolactinPRLprolactinECLIAelectro-chemiluminescence immunoassayCLIAclinical laboratory improvement amendmentsIQASinternal quality assurance systemrregression coefficient.
Quantized correlation coefficient for measuring reproducibility of ChIP-chip data.

PubMed

Peng, Shouyong; Kuroda, Mitzi I; Park, Peter J

2010-07-27

Chromatin immunoprecipitation followed by microarray hybridization (ChIP-chip) is used to study protein-DNA interactions and histone modifications on a genome-scale. To ensure data quality, these experiments are usually performed in replicates, and a correlation coefficient between replicates is used often to assess reproducibility. However, the correlation coefficient can be misleading because it is affected not only by the reproducibility of the signal but also by the amount of binding signal present in the data. We develop the Quantized correlation coefficient (QCC) that is much less dependent on the amount of signal. This involves discretization of data into set of quantiles (quantization), a merging procedure to group the background probes, and recalculation of the Pearson correlation coefficient. This procedure reduces the influence of the background noise on the statistic, which then properly focuses more on the reproducibility of the signal. The performance of this procedure is tested in both simulated and real ChIP-chip data. For replicates with different levels of enrichment over background and coverage, we find that QCC reflects reproducibility more accurately and is more robust than the standard Pearson or Spearman correlation coefficients. The quantization and the merging procedure can also suggest a proper quantile threshold for separating signal from background for further analysis. To measure reproducibility of ChIP-chip data correctly, a correlation coefficient that is robust to the amount of signal present should be used. QCC is one such measure. The QCC statistic can also be applied in a variety of other contexts for measuring reproducibility, including analysis of array CGH data for DNA copy number and gene expression data.
Generalization of Clustering Coefficients to Signed Correlation Networks

PubMed Central

Costantini, Giulio; Perugini, Marco

2014-01-01

The recent interest in network analysis applications in personality psychology and psychopathology has put forward new methodological challenges. Personality and psychopathology networks are typically based on correlation matrices and therefore include both positive and negative edge signs. However, some applications of network analysis disregard negative edges, such as computing clustering coefficients. In this contribution, we illustrate the importance of the distinction between positive and negative edges in networks based on correlation matrices. The clustering coefficient is generalized to signed correlation networks: three new indices are introduced that take edge signs into account, each derived from an existing and widely used formula. The performances of the new indices are illustrated and compared with the performances of the unsigned indices, both on a signed simulated network and on a signed network based on actual personality psychology data. The results show that the new indices are more resistant to sample variations in correlation networks and therefore have higher convergence compared with the unsigned indices both in simulated networks and with real data. PMID:24586367
Correlation between mass transfer coefficient kLa and relevant operating parameters in cylindrical disposable shaken bioreactors on a bench-to-pilot scale.

PubMed

Klöckner, Wolf; Gacem, Riad; Anderlei, Tibor; Raven, Nicole; Schillberg, Stefan; Lattermann, Clemens; Büchs, Jochen

2013-12-02

Among disposable bioreactor systems, cylindrical orbitally shaken bioreactors show important advantages. They provide a well-defined hydrodynamic flow combined with excellent mixing and oxygen transfer for mammalian and plant cell cultivations. Since there is no known universal correlation between the volumetric mass transfer coefficient for oxygen kLa and relevant operating parameters in such bioreactor systems, the aim of this current study is to experimentally determine a universal kLa correlation. A Respiration Activity Monitoring System (RAMOS) was used to measure kLa values in cylindrical disposable shaken bioreactors and Buckingham's π-Theorem was applied to define a dimensionless equation for kLa. In this way, a scale- and volume-independent kLa correlation was developed and validated in bioreactors with volumes from 2 L to 200 L. The final correlation was used to calculate cultivation parameters at different scales to allow a sufficient oxygen supply of tobacco BY-2 cell suspension cultures. The resulting equation can be universally applied to calculate the mass transfer coefficient for any of seven relevant cultivation parameters such as the reactor diameter, the shaking frequency, the filling volume, the viscosity, the oxygen diffusion coefficient, the gravitational acceleration or the shaking diameter within an accuracy range of +/- 30%. To our knowledge, this is the first kLa correlation that has been defined and validated for the cited bioreactor system on a bench-to-pilot scale.
An improved method based on wavelet coefficient correlation to filter noise in Doppler ultrasound blood flow signals

NASA Astrophysics Data System (ADS)

Wan, Renzhi; Zu, Yunxiao; Shao, Lin

2018-04-01

The blood echo signal maintained through Medical ultrasound Doppler devices would always include vascular wall pulsation signal .The traditional method to de-noise wall signal is using high-pass filter, which will also remove the lowfrequency part of the blood flow signal. Some scholars put forward a method based on region selective reduction, which at first estimates of the wall pulsation signals and then removes the wall signal from the mixed signal. Apparently, this method uses the correlation between wavelet coefficients to distinguish blood signal from wall signal, but in fact it is a kind of wavelet threshold de-noising method, whose effect is not so much ideal. In order to maintain a better effect, this paper proposes an improved method based on wavelet coefficient correlation to separate blood signal and wall signal, and simulates the algorithm by computer to verify its validity.
Correlation Between Minimum Apparent Diffusion Coefficient (ADCmin) and Tumor Cellularity: A Meta-analysis.

PubMed

Surov, Alexey; Meyer, Hans Jonas; Wienke, Andreas

2017-07-01

Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) technique based on measure of water diffusion that can provide information about tissue microstructure, especially about cell count. Increase of cell density induces restriction of water diffusion and decreases apparent diffusion coefficient (ADC). ADC can be divided into three sub-parameters: ADC minimum or ADC min , mean ADC or ADC mean and ADC maximum or ADC max Some studies have suggested that ADC min shows stronger correlations with cell count in comparison to other ADC fractions and may be used as a parameter for estimation of tumor cellularity. The aim of the present meta-analysis was to summarize correlation coefficients between ADC min and cellularity in different tumors based on large patient data. For this analysis, MEDLINE database was screened for associations between ADC and cell count in different tumors up to September 2016. For this work, only data regarding ADC min were included. Overall, 12 publications with 317 patients were identified. Spearman's correlation coefficient was used to analyze associations between ADC min and cellularity. The reported Pearson correlation coefficients in some publications were converted into Spearman correlation coefficients. The pooled correlation coefficient for all included studies was ρ=-0.59 (95% confidence interval (CI)=-0.72 to -0.45), heterogeneity Tau 2 =0.04 (p<0.0001), I 2 =73%, test for overall effect Z=8.67 (p<0.00001). ADC min correlated moderately with tumor cellularity. The calculated correlation coefficient is not stronger in comparison to the reported coefficient for ADC mean and, therefore, ADC min does not represent a better means to reflect cellularity. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.
ppcor: An R Package for a Fast Calculation to Semi-partial Correlation Coefficients.

PubMed

Kim, Seongho

2015-11-01

Lack of a general matrix formula hampers implementation of the semi-partial correlation, also known as part correlation, to the higher-order coefficient. This is because the higher-order semi-partial correlation calculation using a recursive formula requires an enormous number of recursive calculations to obtain the correlation coefficients. To resolve this difficulty, we derive a general matrix formula of the semi-partial correlation for fast computation. The semi-partial correlations are then implemented on an R package ppcor along with the partial correlation. Owing to the general matrix formulas, users can readily calculate the coefficients of both partial and semi-partial correlations without computational burden. The package ppcor further provides users with the level of the statistical significance with its test statistic.
Correlation between mass transfer coefficient kLa and relevant operating parameters in cylindrical disposable shaken bioreactors on a bench-to-pilot scale

PubMed Central

2013-01-01

Background Among disposable bioreactor systems, cylindrical orbitally shaken bioreactors show important advantages. They provide a well-defined hydrodynamic flow combined with excellent mixing and oxygen transfer for mammalian and plant cell cultivations. Since there is no known universal correlation between the volumetric mass transfer coefficient for oxygen kLa and relevant operating parameters in such bioreactor systems, the aim of this current study is to experimentally determine a universal kLa correlation. Results A Respiration Activity Monitoring System (RAMOS) was used to measure kLa values in cylindrical disposable shaken bioreactors and Buckingham’s π-Theorem was applied to define a dimensionless equation for kLa. In this way, a scale- and volume-independent kLa correlation was developed and validated in bioreactors with volumes from 2 L to 200 L. The final correlation was used to calculate cultivation parameters at different scales to allow a sufficient oxygen supply of tobacco BY-2 cell suspension cultures. Conclusion The resulting equation can be universally applied to calculate the mass transfer coefficient for any of seven relevant cultivation parameters such as the reactor diameter, the shaking frequency, the filling volume, the viscosity, the oxygen diffusion coefficient, the gravitational acceleration or the shaking diameter within an accuracy range of +/− 30%. To our knowledge, this is the first kLa correlation that has been defined and validated for the cited bioreactor system on a bench-to-pilot scale. PMID:24289110
[Correlation coefficient-based classification method of hydrological dependence variability: With auto-regression model as example].

PubMed

Zhao, Yu Xi; Xie, Ping; Sang, Yan Fang; Wu, Zi Yi

2018-04-01

Hydrological process evaluation is temporal dependent. Hydrological time series including dependence components do not meet the data consistency assumption for hydrological computation. Both of those factors cause great difficulty for water researches. Given the existence of hydrological dependence variability, we proposed a correlationcoefficient-based method for significance evaluation of hydrological dependence based on auto-regression model. By calculating the correlation coefficient between the original series and its dependence component and selecting reasonable thresholds of correlation coefficient, this method divided significance degree of dependence into no variability, weak variability, mid variability, strong variability, and drastic variability. By deducing the relationship between correlation coefficient and auto-correlation coefficient in each order of series, we found that the correlation coefficient was mainly determined by the magnitude of auto-correlation coefficient from the 1 order to p order, which clarified the theoretical basis of this method. With the first-order and second-order auto-regression models as examples, the reasonability of the deduced formula was verified through Monte-Carlo experiments to classify the relationship between correlation coefficient and auto-correlation coefficient. This method was used to analyze three observed hydrological time series. The results indicated the coexistence of stochastic and dependence characteristics in hydrological process.
Empirical correlations for axial dispersion coefficient and Peclet number in fixed-bed columns.

PubMed

Rastegar, Seyed Omid; Gu, Tingyue

2017-03-24

In this work, a new correlation for the axial dispersion coefficient was obtained using experimental data in the literature for axial dispersion in fixed-bed columns packed with particles. The Chung and Wen correlation, the De Ligny correlation are two popular empirical correlations. However, the former lacks the molecular diffusion term and the latter does not consider bed voidage. The new axial dispersion coefficient correlation in this work was based on additional experimental data in the literature by considering both molecular diffusion and bed voidage. It is more comprehensive and accurate. The Peclet number correlation from the new axial dispersion coefficient correlation on the average leads to 12% lower Peclet number values compared to the values from the Chung and Wen correlation, and in many cases much smaller than those from the De Ligny correlation. Copyright © 2017 Elsevier B.V. All rights reserved.
A Method for Approximating the Bivariate Normal Correlation Coefficient.

ERIC Educational Resources Information Center

Kirk, David B.

Improvements of the Gaussian quadrature in conjunction with the Newton-Raphson iteration technique (TM 000 789) are discussed as effective methods of calculating the bivariate normal correlation coefficient. (CK)
Comprehensive analysis of correlation coefficients estimated from pooling heterogeneous microarray data

PubMed Central

2013-01-01

Background The synthesis of information across microarray studies has been performed by combining statistical results of individual studies (as in a mosaic), or by combining data from multiple studies into a large pool to be analyzed as a single data set (as in a melting pot of data). Specific issues relating to data heterogeneity across microarray studies, such as differences within and between labs or differences among experimental conditions, could lead to equivocal results in a melting pot approach. Results We applied statistical theory to determine the specific effect of different means and heteroskedasticity across 19 groups of microarray data on the sign and magnitude of gene-to-gene Pearson correlation coefficients obtained from the pool of 19 groups. We quantified the biases of the pooled coefficients and compared them to the biases of correlations estimated by an effect-size model. Mean differences across the 19 groups were the main factor determining the magnitude and sign of the pooled coefficients, which showed largest values of bias as they approached ±1. Only heteroskedasticity across the pool of 19 groups resulted in less efficient estimations of correlations than did a classical meta-analysis approach of combining correlation coefficients. These results were corroborated by simulation studies involving either mean differences or heteroskedasticity across a pool of N > 2 groups. Conclusions The combination of statistical results is best suited for synthesizing the correlation between expression profiles of a gene pair across several microarray studies. PMID:23822712
Correlation coefficient measurement of the mode-locked laser tones using four-wave mixing.

PubMed

Anthur, Aravind P; Panapakkam, Vivek; Vujicic, Vidak; Merghem, Kamel; Lelarge, Francois; Ramdane, Abderrahim; Barry, Liam P

2016-06-01

We use four-wave mixing to measure the correlation coefficient of comb tones in a quantum-dash mode-locked laser under passive and active locked regimes. We study the uncertainty in the measurement of the correlation coefficient of the proposed method.

Evaluation of icing drag coefficient correlations applied to iced propeller performance prediction

NASA Technical Reports Server (NTRS)

Miller, Thomas L.; Shaw, R. J.; Korkan, K. D.

1987-01-01

Evaluation of three empirical icing drag coefficient correlations is accomplished through application to a set of propeller icing data. The various correlations represent the best means currently available for relating drag rise to various flight and atmospheric conditions for both fixed-wing and rotating airfoils, and the work presented here ilustrates and evaluates one such application of the latter case. The origins of each of the correlations are discussed, and their apparent capabilities and limitations are summarized. These correlations have been made to be an integral part of a computer code, ICEPERF, which has been designed to calculate iced propeller performance. Comparison with experimental propeller icing data shows generally good agreement, with the quality of the predicted results seen to be directly related to the radial icing extent of each case. The code's capability to properly predict thrust coefficient, power coefficient, and propeller efficiency is shown to be strongly dependent on the choice of correlation selected, as well as upon proper specificatioon of radial icing extent.
Modeling Concordance Correlation Coefficient for Longitudinal Study Data

ERIC Educational Resources Information Center

Ma, Yan; Tang, Wan; Yu, Qin; Tu, X. M.

2010-01-01

Measures of agreement are used in a wide range of behavioral, biomedical, psychosocial, and health-care related research to assess reliability of diagnostic test, psychometric properties of instrument, fidelity of psychosocial intervention, and accuracy of proxy outcome. The concordance correlation coefficient (CCC) is a popular measure of…
Inferential Procedures for Correlation Coefficients Corrected for Attenuation.

ERIC Educational Resources Information Center

Hakstian, A. Ralph; And Others

1988-01-01

A model and computation procedure based on classical test score theory are presented for determination of a correlation coefficient corrected for attenuation due to unreliability. Delta and Monte Carlo method applications are discussed. A power analysis revealed no serious loss in efficiency resulting from correction for attentuation. (TJH)
Quantifying the range of cross-correlated fluctuations using a q- L dependent AHXA coefficient

NASA Astrophysics Data System (ADS)

Wang, Fang; Wang, Lin; Chen, Yuming

2018-03-01

Recently, based on analogous height cross-correlation analysis (AHXA), a cross-correlation coefficient ρ×(L) has been proposed to quantify the levels of cross-correlation on different temporal scales for bivariate series. A limitation of this coefficient is that it cannot capture the full information of cross-correlations on amplitude of fluctuations. In fact, it only detects the cross-correlation at a specific order fluctuation, which might neglect some important information inherited from other order fluctuations. To overcome this disadvantage, in this work, based on the scaling of the qth order covariance and time delay L, we define a two-parameter dependent cross-correlation coefficient ρq(L) to detect and quantify the range and level of cross-correlations. This new version of ρq(L) coefficient leads to the formation of a ρq(L) surface, which not only is able to quantify the level of cross-correlations, but also allows us to identify the range of fluctuation amplitudes that are correlated in two given signals. Applications to the classical ARFIMA models and the binomial multifractal series illustrate the feasibility of this new coefficient ρq(L) . In addition, a statistical test is proposed to quantify the existence of cross-correlations between two given series. Applying our method to the real life empirical data from the 1999-2000 California electricity market, we find that the California power crisis in 2000 destroys the cross-correlation between the price and the load series but does not affect the correlation of the load series during and before the crisis.
Attenuation of the Squared Canonical Correlation Coefficient under Varying Estimates of Score Reliability

ERIC Educational Resources Information Center

Wilson, Celia M.

2010-01-01

Research pertaining to the distortion of the squared canonical correlation coefficient has traditionally been limited to the effects of sampling error and associated correction formulas. The purpose of this study was to compare the degree of attenuation of the squared canonical correlation coefficient under varying conditions of score reliability.…
Reducing Bias and Error in the Correlation Coefficient Due to Nonnormality.

PubMed

Bishara, Anthony J; Hittner, James B

2015-10-01

It is more common for educational and psychological data to be nonnormal than to be approximately normal. This tendency may lead to bias and error in point estimates of the Pearson correlation coefficient. In a series of Monte Carlo simulations, the Pearson correlation was examined under conditions of normal and nonnormal data, and it was compared with its major alternatives, including the Spearman rank-order correlation, the bootstrap estimate, the Box-Cox transformation family, and a general normalizing transformation (i.e., rankit), as well as to various bias adjustments. Nonnormality caused the correlation coefficient to be inflated by up to +.14, particularly when the nonnormality involved heavy-tailed distributions. Traditional bias adjustments worsened this problem, further inflating the estimate. The Spearman and rankit correlations eliminated this inflation and provided conservative estimates. Rankit also minimized random error for most sample sizes, except for the smallest samples ( n = 10), where bootstrapping was more effective. Overall, results justify the use of carefully chosen alternatives to the Pearson correlation when normality is violated.
Reducing Bias and Error in the Correlation Coefficient Due to Nonnormality

PubMed Central

Hittner, James B.

2014-01-01

It is more common for educational and psychological data to be nonnormal than to be approximately normal. This tendency may lead to bias and error in point estimates of the Pearson correlation coefficient. In a series of Monte Carlo simulations, the Pearson correlation was examined under conditions of normal and nonnormal data, and it was compared with its major alternatives, including the Spearman rank-order correlation, the bootstrap estimate, the Box–Cox transformation family, and a general normalizing transformation (i.e., rankit), as well as to various bias adjustments. Nonnormality caused the correlation coefficient to be inflated by up to +.14, particularly when the nonnormality involved heavy-tailed distributions. Traditional bias adjustments worsened this problem, further inflating the estimate. The Spearman and rankit correlations eliminated this inflation and provided conservative estimates. Rankit also minimized random error for most sample sizes, except for the smallest samples (n = 10), where bootstrapping was more effective. Overall, results justify the use of carefully chosen alternatives to the Pearson correlation when normality is violated. PMID:29795841
QSPR modeling of octanol/water partition coefficient of antineoplastic agents by balance of correlations.

PubMed

Toropov, Andrey A; Toropova, Alla P; Raska, Ivan; Benfenati, Emilio

2010-04-01

Three different splits into the subtraining set (n = 22), the set of calibration (n = 21), and the test set (n = 12) of 55 antineoplastic agents have been examined. By the correlation balance of SMILES-based optimal descriptors quite satisfactory models for the octanol/water partition coefficient have been obtained on all three splits. The correlation balance is the optimization of a one-variable model with a target function that provides both the maximal values of the correlation coefficient for the subtraining and calibration set and the minimum of the difference between the above-mentioned correlation coefficients. Thus, the calibration set is a preliminary test set. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.
Statistics corner: A guide to appropriate use of correlation coefficient in medical research.

PubMed

Mukaka, M M

2012-09-01

Correlation is a statistical method used to assess a possible linear association between two continuous variables. It is simple both to calculate and to interpret. However, misuse of correlation is so common among researchers that some statisticians have wished that the method had never been devised at all. The aim of this article is to provide a guide to appropriate use of correlation in medical research and to highlight some misuse. Examples of the applications of the correlation coefficient have been provided using data from statistical simulations as well as real data. Rule of thumb for interpreting size of a correlation coefficient has been provided.
Observations of copolar correlation coefficient through a bright band at vertical incidence

NASA Technical Reports Server (NTRS)

Zrnic, D. S.; Raghavan, R.; Chandrasekar, V.

1994-01-01

This paper discusses an application of polarimetric measurements at vertical incidence. In particular, the correlation coefficients between linear copolar components are examined, and measurements obtained with the National Severe Storms Laboratory (NSSL)'s and National Center for Atmospheric Research (NCAR)'s polarimetric radars are presented. The data are from two well-defined bright bands. A sharp decrease of the correlation coefficient, confined to a height interval of a few hundred meters, marks the bottom of the bright band.
Robust spectral-domain optical coherence tomography speckle model and its cross-correlation coefficient analysis

PubMed Central

Liu, Xuan; Ramella-Roman, Jessica C.; Huang, Yong; Guo, Yuan; Kang, Jin U.

2013-01-01

In this study, we proposed a generic speckle simulation for optical coherence tomography (OCT) signal, by convolving the point spread function (PSF) of the OCT system with the numerically synthesized random sample field. We validated our model and used the simulation method to study the statistical properties of cross-correlation coefficients (XCC) between Ascans which have been recently applied in transverse motion analysis by our group. The results of simulation show that over sampling is essential for accurate motion tracking; exponential decay of OCT signal leads to an under estimate of motion which can be corrected; lateral heterogeneity of sample leads to an over estimate of motion for a few pixels corresponding to the structural boundary. PMID:23456001
Detrended cross-correlation coefficient: Application to predict apoptosis protein subcellular localization.

PubMed

Liang, Yunyun; Liu, Sanyang; Zhang, Shengli

2016-12-01

Apoptosis, or programed cell death, plays a central role in the development and homeostasis of an organism. Obtaining information on subcellular location of apoptosis proteins is very helpful for understanding the apoptosis mechanism. The prediction of subcellular localization of an apoptosis protein is still a challenging task, and existing methods mainly based on protein primary sequences. In this paper, we introduce a new position-specific scoring matrix (PSSM)-based method by using detrended cross-correlation (DCCA) coefficient of non-overlapping windows. Then a 190-dimensional (190D) feature vector is constructed on two widely used datasets: CL317 and ZD98, and support vector machine is adopted as classifier. To evaluate the proposed method, objective and rigorous jackknife cross-validation tests are performed on the two datasets. The results show that our approach offers a novel and reliable PSSM-based tool for prediction of apoptosis protein subcellular localization. Copyright © 2016 Elsevier Inc. All rights reserved.
Online physician review websites poorly correlate to a validated metric of patient satisfaction.

PubMed

Chen, Jennwood; Presson, Angela; Zhang, Chong; Ray, David; Finlayson, Samuel; Glasgow, Robert

2018-07-01

Physician review websites such as Vitals and Healthgrades are becoming an increasingly popular tool for patients to choose providers. We hypothesized that the scores of these surveys poorly represent the true value of patient satisfaction when compared to a validated survey instrument. Answers from Vitals and Healthgrades online surveys were compared to the Press Ganey Medical Practice Survey (PGMPS) for 200 faculty members at a university hospital for FY15. Weighted Pearson's correlation was used to compare Healthgrades and Vitals to PGMPS. While statistically significant, both Vitals and Healthgrades had very low correlations with the PGMPS with weighted coefficients of 0.18 (95% confidence interval: 0.02-0.34, P = 0.025) and 0.27 (95% confidence interval: 0.12-0.42, P < 0.001), respectively. Online physician rating websites such as Vitals and Healthgrades poorly correlate with the PGMPS, a validated measure of patient satisfaction. Patients should be aware of these limitations and, consequently, should have access to the most accurate measure of patient satisfaction. Copyright © 2018 Elsevier Inc. All rights reserved.
Gender and Age Analyses of NIRS/STAI Pearson Correlation Coefficients at Resting State.

PubMed

Matsumoto, T; Fuchita, Y; Ichikawa, K; Fukuda, Y; Takemura, N; Sakatani, K

2016-01-01

According to the valence asymmetry hypothesis, the left/right asymmetry of PFC activity is correlated with specific emotional responses to mental stress and personality traits. In a previous study we measured spontaneous oscillation of oxy-Hb concentrations in the bilateral PFC at rest in normal adults employing two-channel portable NIRS and computed the laterality index at rest (LIR). We investigated the Pearson correlation coefficient between the LIR and anxiety levels evaluated by the State-Trait Anxiety Inventory (STAI) test. We found that subjects with right-dominant activity at rest showed higher STAI scores, while those with left dominant oxy-Hb changes at rest showed lower STAI scores such that the Pearson correlation coefficient between LIR and STAI was positive. This study performed Bootstrap analysis on the data and showed the following statistics of the target correlation coefficient: mean=0.4925 and lower confidence limit=0.177 with confidence level 0.05. Using the KS-test, we demonstrated that the correlation did not depend on age, whereas it did depend on gender.
Choosing the best index for the average score intraclass correlation coefficient.

PubMed

Shieh, Gwowen

2016-09-01

The intraclass correlation coefficient (ICC)(2) index from a one-way random effects model is widely used to describe the reliability of mean ratings in behavioral, educational, and psychological research. Despite its apparent utility, the essential property of ICC(2) as a point estimator of the average score intraclass correlation coefficient is seldom mentioned. This article considers several potential measures and compares their performance with ICC(2). Analytical derivations and numerical examinations are presented to assess the bias and mean square error of the alternative estimators. The results suggest that more advantageous indices can be recommended over ICC(2) for their theoretical implication and computational ease.
On the validity of the Arrhenius equation for electron attachment rate coefficients.

PubMed

Fabrikant, Ilya I; Hotop, Hartmut

2008-03-28

The validity of the Arrhenius equation for dissociative electron attachment rate coefficients is investigated. A general analysis allows us to obtain estimates of the upper temperature bound for the range of validity of the Arrhenius equation in the endothermic case and both lower and upper bounds in the exothermic case with a reaction barrier. The results of the general discussion are illustrated by numerical examples whereby the rate coefficient, as a function of temperature for dissociative electron attachment, is calculated using the resonance R-matrix theory. In the endothermic case, the activation energy in the Arrhenius equation is close to the threshold energy, whereas in the case of exothermic reactions with an intermediate barrier, the activation energy is found to be substantially lower than the barrier height.
Correlation Between Posttraumatic Growth and Posttraumatic Stress Disorder Symptoms Based on Pearson Correlation Coefficient: A Meta-Analysis.

PubMed

Liu, An-Nuo; Wang, Lu-Lu; Li, Hui-Ping; Gong, Juan; Liu, Xiao-Hong

2017-05-01

The literature on posttraumatic growth (PTG) is burgeoning, with the inconsistencies in the literature of the relationship between PTG and posttraumatic stress disorder (PTSD) symptoms becoming a focal point of attention. Thus, this meta-analysis aims to explore the relationship between PTG and PTSD symptoms through the Pearson correlation coefficient. A systematic search of the literature from January 1996 to November 2015 was completed. We retrieved reports on 63 studies that involved 26,951 patients. The weighted correlation coefficient revealed an effect size of 0.22 with a 95% confidence interval of 0.18 to 0.25. Meta-analysis provides evidence that PTG may be positively correlated with PTSD symptoms and that this correlation may be modified by age, trauma type, and time since trauma. Accordingly, people with high levels of PTG should not be ignored, but rather, they should continue to receive help to alleviate their PTSD symptoms.
Correlation time and diffusion coefficient imaging: application to a granular flow system.

PubMed

Caprihan, A; Seymour, J D

2000-05-01

A parametric method for spatially resolved measurements for velocity autocorrelation functions, R(u)(tau) = , expressed as a sum of exponentials, is presented. The method is applied to a granular flow system of 2-mm oil-filled spheres rotated in a half-filled horizontal cylinder, which is an Ornstein-Uhlenbeck process with velocity autocorrelation function R(u)(tau) = e(- ||tau ||/tau(c)), where tau(c) is the correlation time and D = tau(c) is the diffusion coefficient. The pulsed-field-gradient NMR method consists of applying three different gradient pulse sequences of varying motion sensitivity to distinguish the range of correlation times present for particle motion. Time-dependent apparent diffusion coefficients are measured for these three sequences and tau(c) and D are then calculated from the apparent diffusion coefficient images. For the cylinder rotation rate of 2.3 rad/s, the axial diffusion coefficient at the top center of the free surface was 5.5 x 10(-6) m(2)/s, the correlation time was 3 ms, and the velocity fluctuation or granular temperature was 1.8 x 10(-3) m(2)/s(2). This method is also applicable to study transport in systems involving turbulence and porous media flows. Copyright 2000 Academic Press.
Anthropometry of Women of the U.S. Army--1977. Report Number 4. Correlation Coefficients

DTIC Science & Technology

1980-02-01

S.... •, 0 76 x:. ADo5 //64 ! TECHNICAL REPORT NATICK/TR-80/016 (/ II ANTHROPOMETRY OF WOMEN OF THE U.S. ARMY-1977 Report No. 4 Correlation...NUMBER NATICK/TR-80/016 4. TITLE (and Subtitle) 5. TYPE OF REPORT & PERIOD COVERED ANTHROPOMETRY OF WOMEN OF THE U.S. ARMY--1977 Technical Report REPORT NO... Anthropometry Survey(s) Coefficients of correlation Measurement(s) U.S. Army Correlation coefficients Body size Military personnel Equation(s) Sizes
Correlation Revelation: The Search for Meaning in Pearson's Coefficient

ERIC Educational Resources Information Center

Huhn, Craig

2016-01-01

When the author was first charged with getting a group of students to understand the correlation coefficient, he did not anticipate the topic would challenge his own understanding, let alone cause him to eventually question the very nature of mathematics itself. On the surface, the idea seemed straightforward, one that millions of students across…

Reducing Bias and Error in the Correlation Coefficient Due to Nonnormality

ERIC Educational Resources Information Center

Bishara, Anthony J.; Hittner, James B.

2015-01-01

It is more common for educational and psychological data to be nonnormal than to be approximately normal. This tendency may lead to bias and error in point estimates of the Pearson correlation coefficient. In a series of Monte Carlo simulations, the Pearson correlation was examined under conditions of normal and nonnormal data, and it was compared…
Validation of a scenario-based assessment of critical thinking using an externally validated tool.

PubMed

Buur, Jennifer L; Schmidt, Peggy; Smylie, Dean; Irizarry, Kris; Crocker, Carlos; Tyler, John; Barr, Margaret

2012-01-01

With medical education transitioning from knowledge-based curricula to competency-based curricula, critical thinking skills have emerged as a major competency. While there are validated external instruments for assessing critical thinking, many educators have created their own custom assessments of critical thinking. However, the face validity of these assessments has not been challenged. The purpose of this study was to compare results from a custom assessment of critical thinking with the results from a validated external instrument of critical thinking. Students from the College of Veterinary Medicine at Western University of Health Sciences were administered a custom assessment of critical thinking (ACT) examination and the externally validated instrument, California Critical Thinking Skills Test (CCTST), in the spring of 2011. Total scores and sub-scores from each exam were analyzed for significant correlations using Pearson correlation coefficients. Significant correlations between ACT Blooms 2 and deductive reasoning and total ACT score and deductive reasoning were demonstrated with correlation coefficients of 0.24 and 0.22, respectively. No other statistically significant correlations were found. The lack of significant correlation between the two examinations illustrates the need in medical education to externally validate internal custom assessments. Ultimately, the development and validation of custom assessments of non-knowledge-based competencies will produce higher quality medical professionals.
Overcoming multicollinearity in multiple regression using correlation coefficient

NASA Astrophysics Data System (ADS)

Zainodin, H. J.; Yap, S. J.

2013-09-01

Multicollinearity happens when there are high correlations among independent variables. In this case, it would be difficult to distinguish between the contributions of these independent variables to that of the dependent variable as they may compete to explain much of the similar variance. Besides, the problem of multicollinearity also violates the assumption of multiple regression: that there is no collinearity among the possible independent variables. Thus, an alternative approach is introduced in overcoming the multicollinearity problem in achieving a well represented model eventually. This approach is accomplished by removing the multicollinearity source variables on the basis of the correlation coefficient values based on full correlation matrix. Using the full correlation matrix can facilitate the implementation of Excel function in removing the multicollinearity source variables. It is found that this procedure is easier and time-saving especially when dealing with greater number of independent variables in a model and a large number of all possible models. Hence, in this paper detailed insight of the procedure is shown, compared and implemented.
Optimal portfolio strategy with cross-correlation matrix composed by DCCA coefficients: Evidence from the Chinese stock market

NASA Astrophysics Data System (ADS)

Sun, Xuelian; Liu, Zixian

2016-02-01

In this paper, a new estimator of correlation matrix is proposed, which is composed of the detrended cross-correlation coefficients (DCCA coefficients), to improve portfolio optimization. In contrast to Pearson's correlation coefficients (PCC), DCCA coefficients acquired by the detrended cross-correlation analysis (DCCA) method can describe the nonlinear correlation between assets, and can be decomposed in different time scales. These properties of DCCA make it possible to improve the investment effect and more valuable to investigate the scale behaviors of portfolios. The minimum variance portfolio (MVP) model and the Mean-Variance (MV) model are used to evaluate the effectiveness of this improvement. Stability analysis shows the effect of two kinds of correlation matrices on the estimation error of portfolio weights. The observed scale behaviors are significant to risk management and could be used to optimize the portfolio selection.
Negative Correlation between the Diffusion Coefficient and Transcriptional Activity of the Glucocorticoid Receptor.

PubMed

Mikuni, Shintaro; Yamamoto, Johtaro; Horio, Takashi; Kinjo, Masataka

2017-08-25

The glucocorticoid receptor (GR) is a transcription factor, which interacts with DNA and other cofactors to regulate gene transcription. Binding to other partners in the cell nucleus alters the diffusion properties of GR. Raster image correlation spectroscopy (RICS) was applied to quantitatively characterize the diffusion properties of EGFP labeled human GR (EGFP-hGR) and its mutants in the cell nucleus. RICS is an image correlation technique that evaluates the spatial distribution of the diffusion coefficient as a diffusion map. Interestingly, we observed that the averaged diffusion coefficient of EGFP-hGR strongly and negatively correlated with its transcriptional activities in comparison to that of EGFP-hGR wild type and mutants with various transcriptional activities. This result suggests that the decreasing of the diffusion coefficient of hGR was reflected in the high-affinity binding to DNA. Moreover, the hyper-phosphorylation of hGR can enhance the transcriptional activity by reduction of the interaction between the hGR and the nuclear corepressors.
Robust Approximations to the Non-Null Distribution of the Product Moment Correlation Coefficient I: The Phi Coefficient.

ERIC Educational Resources Information Center

Edwards, Lynne K.; Meyers, Sarah A.

Correlation coefficients are frequently reported in educational and psychological research. The robustness properties and optimality among practical approximations when phi does not equal 0 with moderate sample sizes are not well documented. Three major approximations and their variations are examined: (1) a normal approximation of Fisher's Z,…
Correlation of the apparent diffusion coefficient and the standardized uptake value in neoplastic lesions: a meta-analysis.

PubMed

Shen, Guohua; Ma, Huan; Liu, Bin; Ren, Pengwei; Kuang, Anren

2017-12-01

Diffusion-weighted imaging and fluorine-18-fluorodeoxyglucose PET are increasingly being recognized as feasible oncological techniques. The apparent diffusion coefficient (ADC) measured by diffusion-weighted imaging and the standardized uptake value (SUV) from fluorine-18-fluorodeoxyglucose PET have similar clinical applications. The aim of this study was to assess the correlation between these two parameters in various cancers. Several major databases were searched for eligible studies. The correlation coefficient (ρ) values were pooled in a random-effects model. Begg's test was used to analyze the existence of publication bias and the sources of heterogeneity were explored in subgroup analyses on the basis of study design, diagnostic method, scanning modality, and tumor type. Thirty-five articles were accepted. The pooled ρ value of all of the accepted studies was -0.30 (95% confidence interval: -0.33 to -0.27), and notable heterogeneity was present (I=69.4%, P<0.001), which indicated a relatively weak negative correlation. The pooled ρ values were -0.26, -0.33, -0.32, and -0.33 for the SUVmax/ADCmean, SUVmax/ADCmin, SUVmean/ADCmean, and SUVmean/ADCmin relationships, respectively. The study design and diagnostic method were potential sources of heterogeneity. Lung cancer showed a stronger correlation (ρ=-0.42) than head and neck cancer (ρ=-0.27), cervical cancer (ρ=-0.21), and breast cancer (ρ=-0.23). A Begg's test indicated no significant publication bias among the accepted studies (P>0.05). The two functional parameters of ADC and SUV showed a very weak inverse correlation, which may contribute toward a sophisticated characterization of tumor biology. However, the findings require further validation with trials with large samples and different tumor types.
Thermal expansion coefficient determination of polylactic acid using digital image correlation

NASA Astrophysics Data System (ADS)

Botean, Adrian-Ioan

2018-02-01

This paper aims determining the linear thermal expansion coefficient (CTE) of polylactic acid (PLA) using an optical method for measuring deformations called digital image correlation method (DIC). Because PLA is often used in making many pieces with 3D printing technology, it is opportune to know this coefficient to obtain a higher degree of precision in the construction of parts and to monitor deformations when these parts are subjected to a thermal gradient. Are used two PLA discs with 20 and 40% degree of filling. In parallel with this approach was determined the linear thermal expansion coefficient (CTE) for the copper cylinder on the surface of which are placed the two discs of PLA.
Research on Ship-Radiated Noise Denoising Using Secondary Variational Mode Decomposition and Correlation Coefficient.

PubMed

Li, Yuxing; Li, Yaan; Chen, Xiao; Yu, Jing

2017-12-26

As the sound signal of ships obtained by sensors contains other many significant characteristics of ships and called ship-radiated noise (SN), research into a denoising algorithm and its application has obtained great significance. Using the advantage of variational mode decomposition (VMD) combined with the correlation coefficient for denoising, a hybrid secondary denoising algorithm is proposed using secondary VMD combined with a correlation coefficient (CC). First, different kinds of simulation signals are decomposed into several bandwidth-limited intrinsic mode functions (IMFs) using VMD, where the decomposition number by VMD is equal to the number by empirical mode decomposition (EMD); then, the CCs between the IMFs and the simulation signal are calculated respectively. The noise IMFs are identified by the CC threshold and the rest of the IMFs are reconstructed in order to realize the first denoising process. Finally, secondary denoising of the simulation signal can be accomplished by repeating the above steps of decomposition, screening and reconstruction. The final denoising result is determined according to the CC threshold. The denoising effect is compared under the different signal-to-noise ratio and the time of decomposition by VMD. Experimental results show the validity of the proposed denoising algorithm using secondary VMD (2VMD) combined with CC compared to EMD denoising, ensemble EMD (EEMD) denoising, VMD denoising and cubic VMD (3VMD) denoising, as well as two denoising algorithms presented recently. The proposed denoising algorithm is applied to feature extraction and classification for SN signals, which can effectively improve the recognition rate of different kinds of ships.
[Correlation of molecular weight and nanofiltration mass transfer coefficient of phenolic acid composition from Salvia miltiorrhiza].

PubMed

Li, Cun-Yu; Wu, Xin; Gu, Jia-Mei; Li, Hong-Yang; Peng, Guo-Ping

2018-04-01

Based on the molecular sieving and solution-diffusion effect in nanofiltration separation, the correlation between initial concentration and mass transfer coefficient of three typical phenolic acids from Salvia miltiorrhiza was fitted to analyze the relationship among mass transfer coefficient, molecular weight and concentration. The experiment showed a linear relationship between operation pressure and membrane flux. Meanwhile, the membrane flux was gradually decayed with the increase of solute concentration. On the basis of the molecular sieving and solution-diffusion effect, the mass transfer coefficient and initial concentration of three phenolic acids showed a power function relationship, and the regression coefficients were all greater than 0.9. The mass transfer coefficient and molecular weight of three phenolic acids were negatively correlated with each other, and the order from high to low is protocatechualdehyde >rosmarinic acid> salvianolic acid B. The separation mechanism of nanofiltration for phenolic acids was further clarified through the analysis of the correlation of molecular weight and nanofiltration mass transfer coefficient. The findings provide references for nanofiltration separation, especially for traditional Chinese medicine with phenolic acids. Copyright© by the Chinese Pharmaceutical Association.
Relationships among the slopes of lines derived from various data analysis techniques and the associated correlation coefficient

NASA Technical Reports Server (NTRS)

Cohen, S. C.

1980-01-01

A technique for fitting a straight line to a collection of data points is given. The relationships between the slopes and correlation coefficients, and between the corresponding standard deviations and correlation coefficient are given.
Research on the Fusion of Dependent Evidence Based on Rank Correlation Coefficient.

PubMed

Shi, Fengjian; Su, Xiaoyan; Qian, Hong; Yang, Ning; Han, Wenhua

2017-10-16

In order to meet the higher accuracy and system reliability requirements, the information fusion for multi-sensor systems is an increasing concern. Dempster-Shafer evidence theory (D-S theory) has been investigated for many applications in multi-sensor information fusion due to its flexibility in uncertainty modeling. However, classical evidence theory assumes that the evidence is independent of each other, which is often unrealistic. Ignoring the relationship between the evidence may lead to unreasonable fusion results, and even lead to wrong decisions. This assumption severely prevents D-S evidence theory from practical application and further development. In this paper, an innovative evidence fusion model to deal with dependent evidence based on rank correlation coefficient is proposed. The model first uses rank correlation coefficient to measure the dependence degree between different evidence. Then, total discount coefficient is obtained based on the dependence degree, which also considers the impact of the reliability of evidence. Finally, the discount evidence fusion model is presented. An example is illustrated to show the use and effectiveness of the proposed method.
Research on the Fusion of Dependent Evidence Based on Rank Correlation Coefficient

PubMed Central

Su, Xiaoyan; Qian, Hong; Yang, Ning; Han, Wenhua

2017-01-01

In order to meet the higher accuracy and system reliability requirements, the information fusion for multi-sensor systems is an increasing concern. Dempster–Shafer evidence theory (D–S theory) has been investigated for many applications in multi-sensor information fusion due to its flexibility in uncertainty modeling. However, classical evidence theory assumes that the evidence is independent of each other, which is often unrealistic. Ignoring the relationship between the evidence may lead to unreasonable fusion results, and even lead to wrong decisions. This assumption severely prevents D–S evidence theory from practical application and further development. In this paper, an innovative evidence fusion model to deal with dependent evidence based on rank correlation coefficient is proposed. The model first uses rank correlation coefficient to measure the dependence degree between different evidence. Then, total discount coefficient is obtained based on the dependence degree, which also considers the impact of the reliability of evidence. Finally, the discount evidence fusion model is presented. An example is illustrated to show the use and effectiveness of the proposed method. PMID:29035341
The Robustness of Designs for Trials with Nested Data against Incorrect Initial Intracluster Correlation Coefficient Estimates

ERIC Educational Resources Information Center

Korendijk, Elly J. H.; Moerbeek, Mirjam; Maas, Cora J. M.

2010-01-01

In the case of trials with nested data, the optimal allocation of units depends on the budget, the costs, and the intracluster correlation coefficient. In general, the intracluster correlation coefficient is unknown in advance and an initial guess has to be made based on published values or subject matter knowledge. This initial estimate is likely…
Health Service Quality Scale: Brazilian Portuguese translation, reliability and validity.

PubMed

Rocha, Luiz Roberto Martins; Veiga, Daniela Francescato; e Oliveira, Paulo Rocha; Song, Elaine Horibe; Ferreira, Lydia Masako

2013-01-17

The Health Service Quality Scale is a multidimensional hierarchical scale that is based on interdisciplinary approach. This instrument was specifically created for measuring health service quality based on marketing and health care concepts. The aim of this study was to translate and culturally adapt the Health Service Quality Scale into Brazilian Portuguese and to assess the validity and reliability of the Brazilian Portuguese version of the instrument. We conducted a cross-sectional, observational study, with public health system patients in a Brazilian university hospital. Validity was assessed using Pearson's correlation coefficient to measure the strength of the association between the Brazilian Portuguese version of the instrument and the SERVQUAL scale. Internal consistency was evaluated using Cronbach's alpha coefficient; the intraclass (ICC) and Pearson's correlation coefficients were used for test-retest reliability. One hundred and sixteen consecutive postoperative patients completed the questionnaire. Pearson's correlation coefficient for validity was 0.20. Cronbach's alpha for the first and second administrations of the final version of the instrument were 0.982 and 0.986, respectively. For test-retest reliability, Pearson's correlation coefficient was 0.89 and ICC was 0.90. The culturally adapted, Brazilian Portuguese version of the Health Service Quality Scale is a valid and reliable instrument to measure health service quality.
The Physical Significance of the Synthetic Running Correlation Coefficient and Its Applications in Oceanic and Atmospheric Studies

NASA Astrophysics Data System (ADS)

Zhao, Jinping; Cao, Yong; Wang, Xin

2018-06-01

In order to study the temporal variations of correlations between two time series, a running correlation coefficient (RCC) could be used. An RCC is calculated for a given time window, and the window is then moved sequentially through time. The current calculation method for RCCs is based on the general definition of the Pearson product-moment correlation coefficient, calculated with the data within the time window, which we call the local running correlation coefficient (LRCC). The LRCC is calculated via the two anomalies corresponding to the two local means, meanwhile, the local means also vary. It is cleared up that the LRCC reflects only the correlation between the two anomalies within the time window but fails to exhibit the contributions of the two varying means. To address this problem, two unchanged means obtained from all available data are adopted to calculate an RCC, which is called the synthetic running correlation coefficient (SRCC). When the anomaly variations are dominant, the two RCCs are similar. However, when the variations of the means are dominant, the difference between the two RCCs becomes obvious. The SRCC reflects the correlations of both the anomaly variations and the variations of the means. Therefore, the SRCCs from different time points are intercomparable. A criterion for the superiority of the RCC algorithm is that the average value of the RCC should be close to the global correlation coefficient calculated using all data. The SRCC always meets this criterion, while the LRCC sometimes fails. Therefore, the SRCC is better than the LRCC for running correlations. We suggest using the SRCC to calculate the RCCs.
Determining Sample Size for Accurate Estimation of the Squared Multiple Correlation Coefficient.

ERIC Educational Resources Information Center

Algina, James; Olejnik, Stephen

2000-01-01

Discusses determining sample size for estimation of the squared multiple correlation coefficient and presents regression equations that permit determination of the sample size for estimating this parameter for up to 20 predictor variables. (SLD)
Application of Cross-Correlation Greens Function Along With FDTD for Fast Computation of Envelope Correlation Coefficient Over Wideband for MIMO Antennas

NASA Astrophysics Data System (ADS)

Sarkar, Debdeep; Srivastava, Kumar Vaibhav

2017-02-01

In this paper, the concept of cross-correlation Green's functions (CGF) is used in conjunction with the finite difference time domain (FDTD) technique for calculation of envelope correlation coefficient (ECC) of any arbitrary MIMO antenna system over wide frequency band. Both frequency-domain (FD) and time-domain (TD) post-processing techniques are proposed for possible application with this FDTD-CGF scheme. The FDTD-CGF time-domain (FDTD-CGF-TD) scheme utilizes time-domain signal processing methods and exhibits significant reduction in ECC computation time as compared to the FDTD-CGF frequency domain (FDTD-CGF-FD) scheme, for high frequency-resolution requirements. The proposed FDTD-CGF based schemes can be applied for accurate and fast prediction of wideband ECC response, instead of the conventional scattering parameter based techniques which have several limitations. Numerical examples of the proposed FDTD-CGF techniques are provided for two-element MIMO systems involving thin-wire half-wavelength dipoles in parallel side-by-side as well as orthogonal arrangements. The results obtained from the FDTD-CGF techniques are compared with results from commercial electromagnetic solver Ansys HFSS, to verify the validity of proposed approach.
Highlighting material structure with transmission electron diffraction correlation coefficient maps.

PubMed

Kiss, Ákos K; Rauch, Edgar F; Lábár, János L

2016-04-01

Correlation coefficient maps are constructed by computing the differences between neighboring diffraction patterns collected in a transmission electron microscope in scanning mode. The maps are shown to highlight material structural features like grain boundaries, second phase particles or dislocations. The inclination of the inner crystal interfaces are directly deduced from the resulting contrast. Copyright © 2016 Elsevier B.V. All rights reserved.
[Validating the Spanish version of the Nursing Activities Score].

PubMed

Sánchez-Sánchez, M M; Arias-Rivera, S; Fraile-Gamo, M P; Thuissard-Vasallo, I J; Frutos-Vivar, F

2015-01-01

Validating workload scores ensures that they are appropriate for the purpose for which they were developed. To validate the Nursing Activities Score (NAS) Spanish version. Observational and prospective study. 1,045 patients who were admitted to a medical-surgical unit and a serious burns unit in 2006 were included. The nurse in charge assessed patient workloads by Nine Equivalent of Nursing Manpower use Score and NAS. To assess the internal consistency of the measurements of NAS, item-test correlations, Cronbach's α and Cronbach's α corrected by omitting each of the items were calculated. The intraobserver and interobserver reliability were assessed with the intraclass correlation coefficient by viewing recordings and Kappa (interobserver reliability) was estimated. For the analysis of internal validity, a factorial principal components analysis was performed. Convergent validity was assessed using the Spearman correlation coefficient values obtained from the Nine Equivalent of Nursing Manpower use Score and Spanish-NAS scales. For internal consistency, 164 questionnaires were analysed and a Cronbach's α of 0.373 was calculated. The intraclass correlation coefficient for intraobserver reliability estimate was 0.837 (95% IC: 0.466-0.950) and 0.662 (95% IC: 0.033-0.882) for interobserver reliability. The estimated kappa was 0.371. For internal validity, exploratory factor analysis showed that the first item explained 58.9% of the variance of the questionnaire. For convergent validity 1006 questionnaires were included and a Spearman correlation coefficient of 0.746 was observed. The psychometric properties of Spanish-NAS are acceptable. Copyright © 2014 Elsevier España, S.L.U. y SEEIUC. All rights reserved.

Intraclass Correlation Coefficients in Hierarchical Designs: Evaluation Using Latent Variable Modeling

ERIC Educational Resources Information Center

Raykov, Tenko

2011-01-01

Interval estimation of intraclass correlation coefficients in hierarchical designs is discussed within a latent variable modeling framework. A method accomplishing this aim is outlined, which is applicable in two-level studies where participants (or generally lower-order units) are clustered within higher-order units. The procedure can also be…
DCCA cross-correlation coefficients reveals the change of both synchronization and oscillation in EEG of Alzheimer disease patients

NASA Astrophysics Data System (ADS)

Chen, Yingyuan; Cai, Lihui; Wang, Ruofan; Song, Zhenxi; Deng, Bin; Wang, Jiang; Yu, Haitao

2018-01-01

Alzheimer's disease (AD) is a degenerative disorder of neural system that affects mainly the older population. Recently, many researches show that the EEG of AD patients can be characterized by EEG slowing, enhanced complexity of the EEG signals, and EEG synchrony. In order to examine the neural synchrony at multi scales, and to find a biomarker that help detecting AD in diagnosis, detrended cross-correlation analysis (DCCA) of EEG signals is applied in this paper. Several parameters, namely DCCA coefficients in the whole brain, DCCA coefficients at a specific scale, maximum DCCA coefficient over the span of all time scales and the corresponding scale of such coefficients, were extracted to examine the synchronization, respectively. The results show that DCCA coefficients have a trend of increase as scale increases, and decreases as electrode distance increases. Comparing DCCA coefficients in AD patients with healthy controls, a decrease of synchronization in the whole brain, and a bigger scale corresponding to maximum correlation is discovered in AD patients. The change of max-correlation scale may relate to the slowing of oscillatory activities. Linear combination of max DCCA coefficient and max-correlation scale reaches a classification accuracy of 90%. From the above results, it is reasonable to conclude that DCCA coefficient reveals the change of both oscillation and synchrony in AD, and thus is a powerful tool to differentiate AD patients from healthy elderly individuals.
Correcting Coefficient Alpha for Correlated Errors: Is [alpha][K]a Lower Bound to Reliability?

ERIC Educational Resources Information Center

Rae, Gordon

2006-01-01

When errors of measurement are positively correlated, coefficient alpha may overestimate the "true" reliability of a composite. To reduce this inflation bias, Komaroff (1997) has proposed an adjusted alpha coefficient, ak. This article shows that ak is only guaranteed to be a lower bound to reliability if the latter does not include correlated…
Statistical analysis on multifractal detrended cross-correlation coefficient for return interval by oriented percolation

NASA Astrophysics Data System (ADS)

Deng, Wei; Wang, Jun

2015-06-01

We investigate and quantify the multifractal detrended cross-correlation of return interval series for Chinese stock markets and a proposed price model, the price model is established by oriented percolation. The return interval describes the waiting time between two successive price volatilities which are above some threshold, the present work is an attempt to quantify the level of multifractal detrended cross-correlation for the return intervals. Further, the concept of MF-DCCA coefficient of return intervals is introduced, and the corresponding empirical research is performed. The empirical results show that the return intervals of SSE and SZSE are weakly positive multifractal power-law cross-correlated, and exhibit the fluctuation patterns of MF-DCCA coefficients. The similar behaviors of return intervals for the price model is also demonstrated.
Validation of drift and diffusion coefficients from experimental data

NASA Astrophysics Data System (ADS)

Riera, R.; Anteneodo, C.

2010-04-01

Many fluctuation phenomena, in physics and other fields, can be modeled by Fokker-Planck or stochastic differential equations whose coefficients, associated with drift and diffusion components, may be estimated directly from the observed time series. Its correct characterization is crucial to determine the system quantifiers. However, due to the finite sampling rates of real data, the empirical estimates may significantly differ from their true functional forms. In the literature, low-order corrections, or even no corrections, have been applied to the finite-time estimates. A frequent outcome consists of linear drift and quadratic diffusion coefficients. For this case, exact corrections have been recently found, from Itô-Taylor expansions. Nevertheless, model validation constitutes a necessary step before determining and applying the appropriate corrections. Here, we exploit the consequences of the exact theoretical results obtained for the linear-quadratic model. In particular, we discuss whether the observed finite-time estimates are actually a manifestation of that model. The relevance of this analysis is put into evidence by its application to two contrasting real data examples in which finite-time linear drift and quadratic diffusion coefficients are observed. In one case the linear-quadratic model is readily rejected while in the other, although the model constitutes a very good approximation, low-order corrections are inappropriate. These examples give warning signs about the proper interpretation of finite-time analysis even in more general diffusion processes.
Confidence Intervals for Squared Semipartial Correlation Coefficients: The Effect of Nonnormality

ERIC Educational Resources Information Center

Algina, James; Keselman, H. J.; Penfield, Randall D.

2010-01-01

The increase in the squared multiple correlation coefficient ([delta]R[superscript 2]) associated with a variable in a regression equation is a commonly used measure of importance in regression analysis. Algina, Keselman, and Penfield found that intervals based on asymptotic principles were typically very inaccurate, even though the sample size…
Estimating a graphical intra-class correlation coefficient (GICC) using multivariate probit-linear mixed models.

PubMed

Yue, Chen; Chen, Shaojie; Sair, Haris I; Airan, Raag; Caffo, Brian S

2015-09-01

Data reproducibility is a critical issue in all scientific experiments. In this manuscript, the problem of quantifying the reproducibility of graphical measurements is considered. The image intra-class correlation coefficient (I2C2) is generalized and the graphical intra-class correlation coefficient (GICC) is proposed for such purpose. The concept for GICC is based on multivariate probit-linear mixed effect models. A Markov Chain Monte Carlo EM (mcm-cEM) algorithm is used for estimating the GICC. Simulation results with varied settings are demonstrated and our method is applied to the KIRBY21 test-retest dataset.
Observed intra-cluster correlation coefficients in a cluster survey sample of patient encounters in general practice in Australia

PubMed Central

Knox, Stephanie A; Chondros, Patty

2004-01-01

Background Cluster sample study designs are cost effective, however cluster samples violate the simple random sample assumption of independence of observations. Failure to account for the intra-cluster correlation of observations when sampling through clusters may lead to an under-powered study. Researchers therefore need estimates of intra-cluster correlation for a range of outcomes to calculate sample size. We report intra-cluster correlation coefficients observed within a large-scale cross-sectional study of general practice in Australia, where the general practitioner (GP) was the primary sampling unit and the patient encounter was the unit of inference. Methods Each year the Bettering the Evaluation and Care of Health (BEACH) study recruits a random sample of approximately 1,000 GPs across Australia. Each GP completes details of 100 consecutive patient encounters. Intra-cluster correlation coefficients were estimated for patient demographics, morbidity managed and treatments received. Intra-cluster correlation coefficients were estimated for descriptive outcomes and for associations between outcomes and predictors and were compared across two independent samples of GPs drawn three years apart. Results Between April 1999 and March 2000, a random sample of 1,047 Australian general practitioners recorded details of 104,700 patient encounters. Intra-cluster correlation coefficients for patient demographics ranged from 0.055 for patient sex to 0.451 for language spoken at home. Intra-cluster correlations for morbidity variables ranged from 0.005 for the management of eye problems to 0.059 for management of psychological problems. Intra-cluster correlation for the association between two variables was smaller than the descriptive intra-cluster correlation of each variable. When compared with the April 2002 to March 2003 sample (1,008 GPs) the estimated intra-cluster correlation coefficients were found to be consistent across samples. Conclusions The demonstrated
A comparison of confidence interval methods for the concordance correlation coefficient and intraclass correlation coefficient with small number of raters.

PubMed

Feng, Dai; Svetnik, Vladimir; Coimbra, Alexandre; Baumgartner, Richard

2014-01-01

The intraclass correlation coefficient (ICC) with fixed raters or, equivalently, the concordance correlation coefficient (CCC) for continuous outcomes is a widely accepted aggregate index of agreement in settings with small number of raters. Quantifying the precision of the CCC by constructing its confidence interval (CI) is important in early drug development applications, in particular in qualification of biomarker platforms. In recent years, there have been several new methods proposed for construction of CIs for the CCC, but their comprehensive comparison has not been attempted. The methods consisted of the delta method and jackknifing with and without Fisher's Z-transformation, respectively, and Bayesian methods with vague priors. In this study, we carried out a simulation study, with data simulated from multivariate normal as well as heavier tailed distribution (t-distribution with 5 degrees of freedom), to compare the state-of-the-art methods for assigning CI to the CCC. When the data are normally distributed, the jackknifing with Fisher's Z-transformation (JZ) tended to provide superior coverage and the difference between it and the closest competitor, the Bayesian method with the Jeffreys prior was in general minimal. For the nonnormal data, the jackknife methods, especially the JZ method, provided the coverage probabilities closest to the nominal in contrast to the others which yielded overly liberal coverage. Approaches based upon the delta method and Bayesian method with conjugate prior generally provided slightly narrower intervals and larger lower bounds than others, though this was offset by their poor coverage. Finally, we illustrated the utility of the CIs for the CCC in an example of a wake after sleep onset (WASO) biomarker, which is frequently used in clinical sleep studies of drugs for treatment of insomnia.
Instrument validation process: a case study using the Paediatric Pain Knowledge and Attitudes Questionnaire.

PubMed

Peirce, Deborah; Brown, Janie; Corkish, Victoria; Lane, Marguerite; Wilson, Sally

2016-06-01

To compare two methods of calculating interrater agreement while determining content validity of the Paediatric Pain Knowledge and Attitudes Questionnaire for use with Australian nurses. Paediatric pain assessment and management documentation was found to be suboptimal revealing a need to assess paediatric nurses' knowledge and attitude to pain. The Paediatric Pain Knowledge and Attitudes Questionnaire was selected as it had been reported as valid and reliable in the United Kingdom with student nurses. The questionnaire required content validity determination prior to use in the Australian context. A two phase process of expert review. Ten paediatric nurses completed a relevancy rating of all 68 questionnaire items. In phase two, five pain experts reviewed the items of the questionnaire that scored an unacceptable item level content validity. Item and scale level content validity indices and intraclass correlation coefficients were calculated. In phase one, 31 items received an item level content validity index <0·78 and the scale level content validity index average was 0·80 which were below levels required for acceptable validity. The intraclass correlation coefficient was 0·47. In phase two, 10 items were amended and four items deleted. The revised questionnaire provided a scale level content validity index average >0·90 and an intraclass correlation coefficient of 0·94 demonstrating excellent agreement between raters therefore acceptable content validity. Equivalent outcomes were achieved using the content validity index and the intraclass correlation coefficient. To assess content validity the content validity index has the advantage of providing an item level score and is a simple calculation. The intraclass correlation coefficient requires statistical knowledge, or support, and has the advantage of accounting for the possibility of chance agreement. © 2016 John Wiley & Sons Ltd.
A novel coefficient for detecting and quantifying asymmetry of California electricity market based on asymmetric detrended cross-correlation analysis.

PubMed

Wang, Fang

2016-06-01

In order to detect and quantify asymmetry of two time series, a novel cross-correlation coefficient is proposed based on recent asymmetric detrended cross-correlation analysis (A-DXA), which we called A-DXA coefficient. The A-DXA coefficient, as an important extension of DXA coefficient ρDXA, contains two directional asymmetric cross-correlated indexes, describing upwards and downwards asymmetric cross-correlations, respectively. By using the information of directional covariance function of two time series and directional variance function of each series itself instead of power-law between the covariance function and time scale, the proposed A-DXA coefficient can well detect asymmetry between the two series no matter whether the cross-correlation is significant or not. By means of the proposed A-DXA coefficient conducted over the asymmetry for California electricity market, we found that the asymmetry between the prices and loads is not significant for daily average data in 1999 yr market (before electricity crisis) but extremely significant for those in 2000 yr market (during the crisis). To further uncover the difference of asymmetry between the years 1999 and 2000, a modified H statistic (MH) and ΔMH statistic are proposed. One of the present contributions is that the high MH values calculated for hourly data exist in majority months in 2000 market. Another important conclusion is that the cross-correlation with downwards dominates over the whole 1999 yr in contrast to the cross-correlation with upwards dominates over the 2000 yr.
A novel coefficient for detecting and quantifying asymmetry of California electricity market based on asymmetric detrended cross-correlation analysis

NASA Astrophysics Data System (ADS)

Wang, Fang

2016-06-01

In order to detect and quantify asymmetry of two time series, a novel cross-correlation coefficient is proposed based on recent asymmetric detrended cross-correlation analysis (A-DXA), which we called A-DXA coefficient. The A-DXA coefficient, as an important extension of DXA coefficient ρ D X A , contains two directional asymmetric cross-correlated indexes, describing upwards and downwards asymmetric cross-correlations, respectively. By using the information of directional covariance function of two time series and directional variance function of each series itself instead of power-law between the covariance function and time scale, the proposed A-DXA coefficient can well detect asymmetry between the two series no matter whether the cross-correlation is significant or not. By means of the proposed A-DXA coefficient conducted over the asymmetry for California electricity market, we found that the asymmetry between the prices and loads is not significant for daily average data in 1999 yr market (before electricity crisis) but extremely significant for those in 2000 yr market (during the crisis). To further uncover the difference of asymmetry between the years 1999 and 2000, a modified H statistic (MH) and ΔMH statistic are proposed. One of the present contributions is that the high MH values calculated for hourly data exist in majority months in 2000 market. Another important conclusion is that the cross-correlation with downwards dominates over the whole 1999 yr in contrast to the cross-correlation with upwards dominates over the 2000 yr.
Colocalization analysis in fluorescence micrographs: verification of a more accurate calculation of pearson's correlation coefficient.

PubMed

Barlow, Andrew L; Macleod, Alasdair; Noppen, Samuel; Sanderson, Jeremy; Guérin, Christopher J

2010-12-01

One of the most routine uses of fluorescence microscopy is colocalization, i.e., the demonstration of a relationship between pairs of biological molecules. Frequently this is presented simplistically by the use of overlays of red and green images, with areas of yellow indicating colocalization of the molecules. Colocalization data are rarely quantified and can be misleading. Our results from both synthetic and biological datasets demonstrate that the generation of Pearson's correlation coefficient between pairs of images can overestimate positive correlation and fail to demonstrate negative correlation. We have demonstrated that the calculation of a thresholded Pearson's correlation coefficient using only intensity values over a determined threshold in both channels produces numerical values that more accurately describe both synthetic datasets and biological examples. Its use will bring clarity and accuracy to colocalization studies using fluorescent microscopy.
Asymptotic properties of Pearson's rank-variate correlation coefficient under contaminated Gaussian model.

PubMed

Ma, Rubao; Xu, Weichao; Zhang, Yun; Ye, Zhongfu

2014-01-01

This paper investigates the robustness properties of Pearson's rank-variate correlation coefficient (PRVCC) in scenarios where one channel is corrupted by impulsive noise and the other is impulsive noise-free. As shown in our previous work, these scenarios that frequently encountered in radar and/or sonar, can be well emulated by a particular bivariate contaminated Gaussian model (CGM). Under this CGM, we establish the asymptotic closed forms of the expectation and variance of PRVCC by means of the well known Delta method. To gain a deeper understanding, we also compare PRVCC with two other classical correlation coefficients, i.e., Spearman's rho (SR) and Kendall's tau (KT), in terms of the root mean squared error (RMSE). Monte Carlo simulations not only verify our theoretical findings, but also reveal the advantage of PRVCC by an example of estimating the time delay in the particular impulsive noise environment.
Statistical test for ΔρDCCA cross-correlation coefficient

NASA Astrophysics Data System (ADS)

Guedes, E. F.; Brito, A. A.; Oliveira Filho, F. M.; Fernandez, B. F.; de Castro, A. P. N.; da Silva Filho, A. M.; Zebende, G. F.

2018-07-01

In this paper we propose a new statistical test for ΔρDCCA, Detrended Cross-Correlation Coefficient Difference, a tool to measure contagion/interdependence effect in time series of size N at different time scale n. For this proposition we analyzed simulated and real time series. The results showed that the statistical significance of ΔρDCCA depends on the size N and the time scale n, and we can define a critical value for this dependency in 90%, 95%, and 99% of confidence level, as will be shown in this paper.
Correlation of human papillomavirus status with apparent diffusion coefficient of diffusion-weighted MRI in head and neck squamous cell carcinomas.

PubMed

Driessen, Juliette P; van Bemmel, Alexander J M; van Kempen, Pauline M W; Janssen, Luuk M; Terhaard, Chris H J; Pameijer, Frank A; Willems, Stefan M; Stegeman, Inge; Grolman, Wilko; Philippens, Marielle E P

2016-04-01

Identification of prognostic patient characteristics in head and neck squamous cell carcinoma (HNSCC) is of great importance. Human papillomavirus (HPV)-positive HNSCCs have favorable response to (chemo)radiotherapy. Apparent diffusion coefficient, derived from diffusion-weighted MRI, has also shown to predict treatment response. The purpose of this study was to evaluate the correlation between HPV status and apparent diffusion coefficient. Seventy-three patients with histologically proven HNSCC were retrospectively analyzed. Mean pretreatment apparent diffusion coefficient was calculated by delineation of total tumor volume on diffusion-weighted MRI. HPV status was analyzed and correlated to apparent diffusion coefficient. Six HNSCCs were HPV-positive. HPV-positive HNSCC showed significantly lower apparent diffusion coefficient compared to HPV-negative. This correlation was independent of other patient characteristics. In HNSCC, positive HPV status correlates with low mean apparent diffusion coefficient. The favorable prognostic value of low pretreatment apparent diffusion coefficient might be partially attributed to patients with a positive HPV status. © 2015 Wiley Periodicals, Inc. Head Neck 38: E613-E618, 2016. © 2015 Wiley Periodicals, Inc.
Development and validation of a new Prescription Quality Index

PubMed Central

Hassan, Norul Badriah; Ismail, Hasanah Che; Naing, Lin; Conroy, Ronán M; Abdul Rahman, Abdul Rashid

2010-01-01

AIMS The aims were to develop and validate a new Prescription Quality Index (PQI) for the measurement of prescription quality in chronic diseases. METHODS The PQI were developed and validated based on three separate surveys and one pilot study. Criteria were developed based on literature search, discussions and brainstorming sessions. Validity of the criteria was examined using modified Delphi method. Pre-testing was performed on 30 patients suffering from chronic diseases. The modified version was then subjected to reviews by pharmacists and clinicians in two separate surveys. The rater-based PQI with 22 criteria was then piloted in 120 patients with chronic illnesses. Results were analysed using SPSS version 12.0.1 RESULTS Exploratory principal components analysis revealed multiple factors contributing to prescription quality. Cronbach's α for the entire 22 criteria was 0.60. The average intra-rater and inter-rater reliability showed good to moderate stability (intraclass correlation coefficient 0.76 and 0.52, respectively). The PQI was significantly and negatively correlated with age (correlation coefficient −0.34, P < 0.001), number of drugs in prescriptions (correlation coefficient −0.51, P < 0.001) and number of chronic diseases/conditions (correlation coefficient −0.35, P < 0.001). CONCLUSIONS The PQI is a promising new instrument for measuring prescription quality. It has been shown that the PQI is a valid, reliable and responsive tool to measure quality of prescription in chronic diseases. PMID:20840442
Fluorescence correlation spectroscopy experiments to quantify free diffusion coefficients in reaction-diffusion systems: The case of Ca2 + and its dyes

NASA Astrophysics Data System (ADS)

Sigaut, Lorena; Villarruel, Cecilia; Ponce, María Laura; Ponce Dawson, Silvina

2017-06-01

Many cell signaling pathways involve the diffusion of messengers that bind and unbind to and from intracellular components. Quantifying their net transport rate under different conditions then requires having separate estimates of their free diffusion coefficient and binding or unbinding rates. In this paper, we show how performing sets of fluorescence correlation spectroscopy (FCS) experiments under different conditions, it is possible to quantify free diffusion coefficients and on and off rates of reaction-diffusion systems. We develop the theory and present a practical implementation for the case of the universal second messenger, calcium (Ca2 +) and single-wavelength dyes that increase their fluorescence upon Ca2 + binding. We validate the approach with experiments performed in aqueous solutions containing Ca2 + and Fluo4 dextran (both in its high and low affinity versions). Performing FCS experiments with tetramethylrhodamine-dextran in Xenopus laevis oocytes, we infer the corresponding free diffusion coefficients in the cytosol of these cells. Our approach can be extended to other physiologically relevant reaction-diffusion systems to quantify biophysical parameters that determine the dynamics of various variables of interest.
CFD Extraction of Heat Transfer Coefficient in Cryogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Yang, H. Q.; West, Jeff

2015-01-01

Current reduced-order thermal model for cryogenic propellant tanks is based on correlations built for flat plates collected in the 1950's. The use of these correlations suffers from inaccurate geometry representation; inaccurate gravity orientation; ambiguous length scale; and lack of detailed validation. This study uses first-principles based CFD methodology to compute heat transfer from the tank wall to the cryogenic fluids and extracts and correlates the equivalent heat transfer coefficient to support reduced-order thermal model. The CFD tool was first validated against available experimental data and commonly used correlations for natural convection along a vertically heated wall. Good agreements between the present prediction and experimental data have been found for flows in laminar as well turbulent regimes. The convective heat transfer between the tank wall and cryogenic propellant, and that between the tank wall and ullage gas were then simulated. The results showed that the commonly used heat transfer correlations for either vertical or horizontal plate over-predict heat transfer rate for the cryogenic tank, in some cases by as much as one order of magnitude. A characteristic length scale has been defined that can correlate all heat transfer coefficients for different fill levels into a single curve. This curve can be used for the reduced-order heat transfer model analysis.
Initial Ship Design Using a Pearson Correlation Coefficient and Artificial Intelligence Techniques

NASA Astrophysics Data System (ADS)

Moon, Byung Young; Kim, Soo Young; Kang, Gyung Ju

In this paper we analyzed correlation between geometrical character and resistance, and effective horse power by using Pearson correlation coefficient which is one of the data mining methods. Also we made input data to ship's geometrical character which has strong correlation with output data. We calculated effective horse power and resistance by using Neuro-Fuzzy system. To verify the calculation, 9 of 11 container ships' data were improved as data of Neuro-Fuzzy system and the others were improved as verification data. After analyzing rate of error between existing data and calculation data, we concluded that calculation data have sound agreement with existing data.

Relative validity of an FFQ to estimate daily food and nutrient intakes for Chilean adults.

PubMed

Dehghan, Mahshid; Martinez, Solange; Zhang, Xiaohe; Seron, Pamela; Lanas, Fernando; Islam, Shofiqul; Merchant, Anwar T

2013-10-01

FFQ are commonly used to rank individuals by their food and nutrient intakes in large epidemiological studies. The purpose of the present study was to develop and validate an FFQ to rank individuals participating in an ongoing Prospective Urban and Rural Epidemiological (PURE) study in Chile. An FFQ and four 24 h dietary recalls were completed over 1 year. Pearson correlation coefficients, energy-adjusted and de-attenuated correlations and weighted kappa were computed between the dietary recalls and the FFQ. The level of agreement between the two dietary assessment methods was evaluated by Bland-Altman analysis. Temuco, Chile. Overall, 166 women and men enrolled in the present study. One hundred men and women participated in FFQ development and sixty-six individuals participated in FFQ validation. The FFQ consisted of 109 food items. For nutrients, the crude correlation coefficients between the dietary recalls and FFQ varied from 0.14 (protein) to 0.44 (fat). Energy adjustment and de-attenuation improved correlation coefficients and almost all correlation coefficients exceeded 0.40. Similar correlation coefficients were observed for food groups; the highest de-attenuated energy adjusted correlation coefficient was found for margarine and butter (0.75) and the lowest for potatoes (0.12). The FFQ showed moderate to high agreement for most nutrients and food groups, and can be used to rank individuals based on energy, nutrient and food intakes. The validation study was conducted in a unique setting and indicated that the tool is valid for use by adults in Chile.
Confidence Intervals and "F" Tests for Intraclass Correlation Coefficients Based on Three-Way Mixed Effects Models

ERIC Educational Resources Information Center

Zhou, Hong; Muellerleile, Paige; Ingram, Debra; Wong, Seok P.

2011-01-01

Intraclass correlation coefficients (ICCs) are commonly used in behavioral measurement and psychometrics when a researcher is interested in the relationship among variables of a common class. The formulas for deriving ICCs, or generalizability coefficients, vary depending on which models are specified. This article gives the equations for…
Using beta coefficients to impute missing correlations in meta-analysis research: Reasons for caution.

PubMed

Roth, Philip L; Le, Huy; Oh, In-Sue; Van Iddekinge, Chad H; Bobko, Philip

2018-06-01

Meta-analysis has become a well-accepted method for synthesizing empirical research about a given phenomenon. Many meta-analyses focus on synthesizing correlations across primary studies, but some primary studies do not report correlations. Peterson and Brown (2005) suggested that researchers could use standardized regression weights (i.e., beta coefficients) to impute missing correlations. Indeed, their beta estimation procedures (BEPs) have been used in meta-analyses in a wide variety of fields. In this study, the authors evaluated the accuracy of BEPs in meta-analysis. We first examined how use of BEPs might affect results from a published meta-analysis. We then developed a series of Monte Carlo simulations that systematically compared the use of existing correlations (that were not missing) to data sets that incorporated BEPs (that impute missing correlations from corresponding beta coefficients). These simulations estimated ρ̄ (mean population correlation) and SDρ (true standard deviation) across a variety of meta-analytic conditions. Results from both the existing meta-analysis and the Monte Carlo simulations revealed that BEPs were associated with potentially large biases when estimating ρ̄ and even larger biases when estimating SDρ. Using only existing correlations often substantially outperformed use of BEPs and virtually never performed worse than BEPs. Overall, the authors urge a return to the standard practice of using only existing correlations in meta-analysis. (PsycINFO Database Record (c) 2018 APA, all rights reserved).
[The appraisal of reliability and validity of subjective workload assessment technique and NASA-task load index].

PubMed

Xiao, Yuan-mei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia

2005-06-01

To test the reliability and validity of two mental workload assessment scales, i.e. subjective workload assessment technique (SWAT) and NASA task load index (NASA-TLX). One thousand two hundred and sixty-eight mental workers were sampled from various kinds of occupations, such as scientific research, education, administration and medicine, etc, with randomized cluster sampling. The re-test reliability, split-half reliability, Cronbach's alpha coefficient and correlation coefficients between item score and total score were adopted to test the reliability. The test of validity included structure validity. The re-test reliability coefficients of these two scales and their items were ranged from 0.516 to 0.753 (P < 0.01), indicating the two scales had good re-test reliability; the split-half reliability of SWAT was 0.645, and its Cronbach's alpha coefficient was more than 0.80, all the correlation coefficients between its items score and total score were more than 0.70; as for NASA-TLX, both the split-half reliability and Cronbach's alpha coefficient were more than 0.80, the correlation coefficients between its items score and total score were all more than 0.60 (P < 0.01) except the item of performance. Both scales had good inner consistency. The Pearson correlation coefficient between the two scales was 0.492 (P < 0.01), implying the results of the two scales had good consistency. Factor analysis showed that the two scales had good structure validity. Both SWAT and NASA-TLX have good reliability and validity and may be used as a valid tool to assess mental workload in China after being revised properly.
[Cross-cultural adaptation and validation of the Health and Taste Attitude Scale (HTAS) in Portuguese].

PubMed

Koritar, Priscila; Philippi, Sonia Tucunduva; Alvarenga, Marle dos Santos; Santos, Bernardo dos

2014-08-01

The scope of this study was to show the cross-cultural adaptation and validation of the Health and Taste Attitude Scale in Portuguese. The methodology included translation of the scale; evaluation of conceptual, operational and item-based equivalence by 14 experts and 51 female undergraduates; semantic equivalence and measurement assessment by 12 bilingual women by the paired t-test, the Pearson correlation coefficient and the coefficient intraclass correlation; internal consistency and test-retest reliability by Cronbach's alpha and intraclass correlation coefficient, respectively, after application on 216 female undergraduates; assessment of discriminant and concurrent validity via the t-test and Spearman's correlation coefficient, respectively, in addition to Confirmatory Factor and Exploratory Factor Analysis. The scale was considered adequate and easily understood by the experts and university students and presented good internal consistency and reliability (µ 0.86, ICC 0.84). The results show that the scale is valid and can be used in studies with women to better understand attitudes related to taste.
Correlation-coefficient-based fast template matching through partial elimination.

PubMed

Mahmood, Arif; Khan, Sohaib

2012-04-01

Partial computation elimination techniques are often used for fast template matching. At a particular search location, computations are prematurely terminated as soon as it is found that this location cannot compete with an already known best match location. Due to the nonmonotonic growth pattern of the correlation-based similarity measures, partial computation elimination techniques have been traditionally considered inapplicable to speed up these measures. In this paper, we show that partial elimination techniques may be applied to a correlation coefficient by using a monotonic formulation, and we propose basic-mode and extended-mode partial correlation elimination algorithms for fast template matching. The basic-mode algorithm is more efficient on small template sizes, whereas the extended mode is faster on medium and larger templates. We also propose a strategy to decide which algorithm to use for a given data set. To achieve a high speedup, elimination algorithms require an initial guess of the peak correlation value. We propose two initialization schemes including a coarse-to-fine scheme for larger templates and a two-stage technique for small- and medium-sized templates. Our proposed algorithms are exact, i.e., having exhaustive equivalent accuracy, and are compared with the existing fast techniques using real image data sets on a wide variety of template sizes. While the actual speedups are data dependent, in most cases, our proposed algorithms have been found to be significantly faster than the other algorithms.
A comparison of confidence interval methods for the intraclass correlation coefficient in community-based cluster randomization trials with a binary outcome.

PubMed

Braschel, Melissa C; Svec, Ivana; Darlington, Gerarda A; Donner, Allan

2016-04-01

Many investigators rely on previously published point estimates of the intraclass correlation coefficient rather than on their associated confidence intervals to determine the required size of a newly planned cluster randomized trial. Although confidence interval methods for the intraclass correlation coefficient that can be applied to community-based trials have been developed for a continuous outcome variable, fewer methods exist for a binary outcome variable. The aim of this study is to evaluate confidence interval methods for the intraclass correlation coefficient applied to binary outcomes in community intervention trials enrolling a small number of large clusters. Existing methods for confidence interval construction are examined and compared to a new ad hoc approach based on dividing clusters into a large number of smaller sub-clusters and subsequently applying existing methods to the resulting data. Monte Carlo simulation is used to assess the width and coverage of confidence intervals for the intraclass correlation coefficient based on Smith's large sample approximation of the standard error of the one-way analysis of variance estimator, an inverted modified Wald test for the Fleiss-Cuzick estimator, and intervals constructed using a bootstrap-t applied to a variance-stabilizing transformation of the intraclass correlation coefficient estimate. In addition, a new approach is applied in which clusters are randomly divided into a large number of smaller sub-clusters with the same methods applied to these data (with the exception of the bootstrap-t interval, which assumes large cluster sizes). These methods are also applied to a cluster randomized trial on adolescent tobacco use for illustration. When applied to a binary outcome variable in a small number of large clusters, existing confidence interval methods for the intraclass correlation coefficient provide poor coverage. However, confidence intervals constructed using the new approach combined with Smith
Cluster structure in the correlation coefficient matrix can be characterized by abnormal eigenvalues

NASA Astrophysics Data System (ADS)

Nie, Chun-Xiao

2018-02-01

In a large number of previous studies, the researchers found that some of the eigenvalues of the financial correlation matrix were greater than the predicted values of the random matrix theory (RMT). Here, we call these eigenvalues as abnormal eigenvalues. In order to reveal the hidden meaning of these abnormal eigenvalues, we study the toy model with cluster structure and find that these eigenvalues are related to the cluster structure of the correlation coefficient matrix. In this paper, model-based experiments show that in most cases, the number of abnormal eigenvalues of the correlation matrix is equal to the number of clusters. In addition, empirical studies show that the sum of the abnormal eigenvalues is related to the clarity of the cluster structure and is negatively correlated with the correlation dimension.
Statistical functions and relevant correlation coefficients of clearness index

NASA Astrophysics Data System (ADS)

Pavanello, Diego; Zaaiman, Willem; Colli, Alessandra; Heiser, John; Smith, Scott

2015-08-01

This article presents a statistical analysis of the sky conditions, during years from 2010 to 2012, for three different locations: the Joint Research Centre site in Ispra (Italy, European Solar Test Installation - ESTI laboratories), the site of National Renewable Energy Laboratory in Golden (Colorado, USA) and the site of Brookhaven National Laboratories in Upton (New York, USA). The key parameter is the clearness index kT, a dimensionless expression of the global irradiance impinging upon a horizontal surface at a given instant of time. In the first part, the sky conditions are characterized using daily averages, giving a general overview of the three sites. In the second part the analysis is performed using data sets with a short-term resolution of 1 sample per minute, demonstrating remarkable properties of the statistical distributions of the clearness index, reinforced by a proof using fuzzy logic methods. Successively some time-dependent correlations between different meteorological variables are presented in terms of Pearson and Spearman correlation coefficients, and introducing a new one.
Apparent Diffusion Coefficient and Dynamic Contrast-Enhanced Magnetic Resonance Imaging in Pancreatic Cancer: Characteristics and Correlation With Histopathologic Parameters.

PubMed

Ma, Wanling; Li, Na; Zhao, Weiwei; Ren, Jing; Wei, Mengqi; Yang, Yong; Wang, Yingmei; Fu, Xin; Zhang, Zhuoli; Larson, Andrew C; Huan, Yi

2016-01-01

To clarify diffusion and perfusion abnormalities and evaluate correlation between apparent diffusion coefficient (ADC), MR perfusion and histopathologic parameters of pancreatic cancer (PC). Eighteen patients with PC underwent diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Parameters of DCE-MRI and ADC of cancer and non-cancerous tissue were compared. Correlation between the rate constant that represents transfer of contrast agent from the arterial blood into the extravascular extracellular space (K, volume of the extravascular extracellular space per unit volume of tissue (Ve), and ADC of PC and histopathologic parameters were analyzed. The rate constant that represents transfer of contrast agent from the extravascular extracellular space into blood plasma, K, tissue volume fraction occupied by vascular space, and ADC of PC were significantly lower than nontumoral pancreases. Ve of PC was significantly higher than that of nontumoral pancreas. Apparent diffusion coefficient and K values of PC were negatively correlated to fibrosis content and fibroblast activation protein staining score. Fibrosis content was positively correlated to Ve. Apparent diffusion coefficient values and parameters of DCE-MRI can differentiate PC from nontumoral pancreases. There are correlations between ADC, K, Ve, and fibrosis content of PC. Fibroblast activation protein staining score of PC is negatively correlated to ADC and K. Apparent diffusion coefficient, K, and Ve may be feasible to predict prognosis of PC.
Urdu translation of the Hamilton Rating Scale for Depression: Results of a validation study

PubMed Central

Hashmi, Ali M.; Naz, Shahana; Asif, Aftab; Khawaja, Imran S.

2016-01-01

Objective: To develop a standardized validated version of the Hamilton Rating Scale for Depression (HAM-D) in Urdu. Methods: After translation of the HAM-D into the Urdu language following standard guidelines, the final Urdu version (HAM-D-U) was administered to 160 depressed outpatients. Inter-item correlation was assessed by calculating Cronbach alpha. Correlation between HAM-D-U scores at baseline and after a 2-week interval was evaluated for test-retest reliability. Moreover, scores of two clinicians on HAM-D-U were compared for inter-rater reliability. For establishing concurrent validity, scores of HAM-D-U and BDI-U were compared by using Spearman correlation coefficient. The study was conducted at Mayo Hospital, Lahore, from May to December 2014. Results: The Cronbach alpha for HAM-D-U was 0.71. Composite scores for HAM-D-U at baseline and after a 2-week interval were also highly correlated with each other (Spearman correlation coefficient 0.83, p-value < 0.01) indicating good test-retest reliability. Composite scores for HAM-D-U and BDI-U were positively correlated with each other (Spearman correlation coefficient 0.85, p < 0.01) indicating good concurrent validity. Scores of two clinicians for HAM-D-U were also positively correlated (Spearman correlation coefficient 0.82, p-value < 0.01) indicated good inter-rater reliability. Conclusion: The HAM-D-U is a valid and reliable instrument for the assessment of Depression. It shows good inter-rater and test-retest reliability. The HAM-D-U can be a tool either for clinical management or research. PMID:28083049
Urdu translation of the Hamilton Rating Scale for Depression: Results of a validation study.

PubMed

Hashmi, Ali M; Naz, Shahana; Asif, Aftab; Khawaja, Imran S

2016-01-01

To develop a standardized validated version of the Hamilton Rating Scale for Depression (HAM-D) in Urdu. After translation of the HAM-D into the Urdu language following standard guidelines, the final Urdu version (HAM-D-U) was administered to 160 depressed outpatients. Inter-item correlation was assessed by calculating Cronbach alpha. Correlation between HAM-D-U scores at baseline and after a 2-week interval was evaluated for test-retest reliability. Moreover, scores of two clinicians on HAM-D-U were compared for inter-rater reliability. For establishing concurrent validity, scores of HAM-D-U and BDI-U were compared by using Spearman correlation coefficient. The study was conducted at Mayo Hospital, Lahore, from May to December 2014. The Cronbach alpha for HAM-D-U was 0.71. Composite scores for HAM-D-U at baseline and after a 2-week interval were also highly correlated with each other (Spearman correlation coefficient 0.83, p-value < 0.01) indicating good test-retest reliability. Composite scores for HAM-D-U and BDI-U were positively correlated with each other (Spearman correlation coefficient 0.85, p < 0.01) indicating good concurrent validity. Scores of two clinicians for HAM-D-U were also positively correlated (Spearman correlation coefficient 0.82, p-value < 0.01) indicated good inter-rater reliability. The HAM-D-U is a valid and reliable instrument for the assessment of Depression. It shows good inter-rater and test-retest reliability. The HAM-D-U can be a tool either for clinical management or research.
Sample Size Calculation for Estimating or Testing a Nonzero Squared Multiple Correlation Coefficient

ERIC Educational Resources Information Center

Krishnamoorthy, K.; Xia, Yanping

2008-01-01

The problems of hypothesis testing and interval estimation of the squared multiple correlation coefficient of a multivariate normal distribution are considered. It is shown that available one-sided tests are uniformly most powerful, and the one-sided confidence intervals are uniformly most accurate. An exact method of calculating sample size to…
Ghost imaging based on Pearson correlation coefficients

NASA Astrophysics Data System (ADS)

Yu, Wen-Kai; Yao, Xu-Ri; Liu, Xue-Feng; Li, Long-Zhen; Zhai, Guang-Jie

2015-05-01

Correspondence imaging is a new modality of ghost imaging, which can retrieve a positive/negative image by simple conditional averaging of the reference frames that correspond to relatively large/small values of the total intensity measured at the bucket detector. Here we propose and experimentally demonstrate a more rigorous and general approach in which a ghost image is retrieved by calculating a Pearson correlation coefficient between the bucket detector intensity and the brightness at a given pixel of the reference frames, and at the next pixel, and so on. Furthermore, we theoretically provide a statistical interpretation of these two imaging phenomena, and explain how the error depends on the sample size and what kind of distribution the error obeys. According to our analysis, the image signal-to-noise ratio can be greatly improved and the sampling number reduced by means of our new method. Project supported by the National Key Scientific Instrument and Equipment Development Project of China (Grant No. 2013YQ030595) and the National High Technology Research and Development Program of China (Grant No. 2013AA122902).
Cross-Correlations and Structures of Aero-Engine Gas Path System Based on DCCA Coefficient and Rooted Tree

NASA Astrophysics Data System (ADS)

Dong, Keqiang; Fan, Jie; Gao, You

2015-12-01

Identifying the mutual interaction is a crucial problem that facilitates the understanding of emerging structures in complex system. We here focus on aero-engine dynamic as an example of complex system. By applying the detrended cross-correlation analysis (DCCA) coefficient method to aero-engine gas path system, we find that the low-spool rotor speed (N1) and high-spool rotor speed (N2) fluctuation series exhibit cross-correlation characteristic. Further, we employ detrended cross-correlation coefficient matrix and rooted tree to investigate the mutual interactions of other gas path variables. The results can infer that the exhaust gas temperature (EGT), N1, N2, fuel flow (WF) and engine pressure ratio (EPR) are main gas path parameters.
Correlation Between the Field Line and Particle Diffusion Coefficients in the Stochastic Fields of a Tokamak

NASA Astrophysics Data System (ADS)

Calvin, Mark; Punjabi, Alkesh

1996-11-01

We use the method of quasi-magnetic surfaces to calculate the correlation between the field line and particle diffusion coefficients. The magnetic topology of a tokamak is perturbed by a spectrum of neighboring resonant resistive modes. The Hamiltonian equations of motion for the field line are integrated numerically. Poincare plots of the quasi-magnetic surfaces are generated initially and after the field line has traversed a considerable distance. From the areas of the quasi-magnetic surfaces and the field line distance, we estimate the field line diffusion coefficient. We start plasma particles on the initial quasi-surface, and calculate the particle diffusion coefficient from our Monte Carlo method (Punjabi A., Boozer A., Lam M., Kim H. and Burke K., J. Plasma Phys.), 44, 405 (1990). We then estimate the correlation between the particle and field diffusion as the strength of the resistive modes is varied.
A quantitative property-property relationship for the internal diffusion coefficients of organic compounds in solid materials.

PubMed

Huang, L; Fantke, P; Ernstoff, A; Jolliet, O

2017-11-01

Indoor releases of organic chemicals encapsulated in solid materials are major contributors to human exposures and are directly related to the internal diffusion coefficient in solid materials. Existing correlations to estimate the diffusion coefficient are only valid for a limited number of chemical-material combinations. This paper develops and evaluates a quantitative property-property relationship (QPPR) to predict diffusion coefficients for a wide range of organic chemicals and materials. We first compiled a training dataset of 1103 measured diffusion coefficients for 158 chemicals in 32 consolidated material types. Following a detailed analysis of the temperature influence, we developed a multiple linear regression model to predict diffusion coefficients as a function of chemical molecular weight (MW), temperature, and material type (adjusted R 2 of .93). The internal validations showed the model to be robust, stable and not a result of chance correlation. The external validation against two separate prediction datasets demonstrated the model has good predicting ability within its applicability domain (Rext2>.8), namely MW between 30 and 1178 g/mol and temperature between 4 and 180°C. By covering a much wider range of organic chemicals and materials, this QPPR facilitates high-throughput estimates of human exposures for chemicals encapsulated in solid materials. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Generalized Correlation Coefficient for Non-Parametric Analysis of Microarray Time-Course Data.

PubMed

Tan, Qihua; Thomassen, Mads; Burton, Mark; Mose, Kristian Fredløv; Andersen, Klaus Ejner; Hjelmborg, Jacob; Kruse, Torben

2017-06-06

Modeling complex time-course patterns is a challenging issue in microarray study due to complex gene expression patterns in response to the time-course experiment. We introduce the generalized correlation coefficient and propose a combinatory approach for detecting, testing and clustering the heterogeneous time-course gene expression patterns. Application of the method identified nonlinear time-course patterns in high agreement with parametric analysis. We conclude that the non-parametric nature in the generalized correlation analysis could be an useful and efficient tool for analyzing microarray time-course data and for exploring the complex relationships in the omics data for studying their association with disease and health.
Validity and cross-cultural adaptation of the persian version of the oxford elbow score.

PubMed

Ebrahimzadeh, Mohammad H; Kachooei, Amir Reza; Vahedi, Ehsan; Moradi, Ali; Mashayekhi, Zeinab; Hallaj-Moghaddam, Mohammad; Azami, Mehran; Birjandinejad, Ali

2014-01-01

Oxford Elbow Score (OES) is a patient-reported questionnaire used to assess outcomes after elbow surgery. The aim of this study was to validate and adapt the OES into Persian language. After forward-backward translation of the OES into Persian, a total number of 92 patients after elbow surgeries completed the Persian OES along with the Persian DASH and SF-36. To assess test-retest reliability, 31 randomly selected patients (34%) completed the Persian OES again after three days while abstaining from all forms of therapeutic regimens. Reliability of the Persian OES was assessed by measuring intraclass correlation coefficient (ICC) for test-retest reliability and Cronbach's alpha for internal consistency. Spearman's correlation coefficient was used to test the construct validity. Cronbach's alpha coefficient was 0.92 showing excellent reliability. Cronbach's alpha for function, pain, and social-psychological subscales was 0.95, 0.86, and 0.85, respectively. Intraclass correlation coefficient (ICC) was 0.85 for the overall questionnaire and 0.90, 0.76, and 0.75 for function, pain, and social-psychological subscales, respectively. Construct validity was confirmed as the Spearman correlation between OES and DASH was 0.80. Persian OES is a valid and reliable patient-reported outcome measure to assess postsurgical elbow status in Persian speaking population.
The Pittsburgh Sleep Quality Index: validation of the Urdu translation.

PubMed

Hashmi, Ali Madeeh; Khawaja, Imran Shuja; Butt, Zeeshan; Umair, Muhammad; Naqvi, Suhaib Haider; Jawad-Ul-Haq

2014-02-01

To translate and validate the Pittsburgh Sleep Quality Index (PSQI), a standardized self-administered questionnaire for the assessment of subjective sleep quality into the Urdu language. Validation study. Mayo Hospital, Lahore, from March to April 2012. The PSQI was translated into Urdu following standard guidelines. The final Urdu version (PSQI-U) was administered to 200 healthy volunteers comprising medical students, nursing staff and doctors. Inter-item correlation was assessed by calculating Cronbach alpha. Correlation of component scores with global score was assessed by calculating Spearman correlation coefficient. Correlation between global PSQI-U scores at baseline with global scores for each PSQI-U and PSQI-E at 4-week interval was evaluated by calculating Spearman correlation coefficient. Moreover, scores on individual items of the scale at baseline were compared with respective scores after 4-week by t-test. One hundred and eighty five (185) participants completed the PSQI-U at baseline. The Cronbach alpha for PSQI-U was 0.56. Scores on individual components of the PSQI-U and composite scores were all highly correlated with each other (all p-values < 0.01). Composite scores for PSQI-U at baseline and PSQI-E at 4-week interval were also highly correlated with each other (Spearman correlation coefficient 0.74, p-value < 0.01) indicating good linguistic interchangeability. Composite scores for PSQI-U at baseline and at 4-week interval were positively correlated with each other (Spearman correlation coefficient 0.70, p < 0.01) indicating good test-retest reliability. The PSQI-U is a valid and reliable instrument for the assessment of sleep quality. It shows good linguistic interchangeability and test-retest reliability in comparison to the original English version when applied to individuals who speak the Urdu language. The PSQI-U can be a tool either for clinical management or research.

Validity and Reliability of the Turkish Version of the DSM-5 Posttraumatic Stress Symptom Severity Scale-Child Form.

PubMed

Yalin Sapmaz, Şermin; Ergin, Dilek; Özek Erkuran, Handan; Şen Celasin, Nesrin; Öztürk, Masum; Karaarslan, Duygu; Köroğlu, Ertuğrul; Aydemir, Ömer

2017-09-01

This study assessed the validity and reliability of the Turkish version of the DSM-5 Posttraumatic Stress Symptom Severity Scale-Child Form for use among the Turkish population. The study group consisted of 30 patients that had been treated in a child psychiatry unit and diagnosed with posttraumatic stress disorder and 83 healthy volunteers that were attending middle or high school during the study period. For reliability analyses, the internal consistency coefficient and the test-retest correlation coefficient were measured. For validity analyses, the exploratory factor analysis and correlation analysis with the Child Posttraumatic Stress Reaction Index for concurrent validity were measured. The Cronbach's alpha (the internal consistency coefficient) of the scale was 0.909, and the test-retest correlation coefficient was 0.663. One factor that could explain 58.5% of the variance was obtained and was congruent with the original construct of the scale. As for concurrent validity, the scale showed high correlation with the Child Posttraumatic Stress Reaction Index. It was concluded that the Turkish version of the DSM-5 Posttraumatic Stress Symptom Severity Scale-Child Form can be used as a valid and reliable tool.
Correlation between apparent diffusion coefficient (ADC) and cellularity is different in several tumors: a meta-analysis.

PubMed

Surov, Alexey; Meyer, Hans Jonas; Wienke, Andreas

2017-08-29

The purpose of this meta-analysis was to provide clinical evidence regarding relationship between ADC and cellularity in different tumors based on large patient data. Medline library was screened for associations between ADC and cell count in different tumors up to September 2016. Only publications in English were extracted. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement (PRISMA) was used for the research. Overall, 39 publications with 1530 patients were included into the analysis. The following data were extracted from the literature: authors, year of publication, number of patients, tumor type, and correlation coefficients. The pooled correlation coefficient for all studies was ρ = -0.56 (95 % CI = [-0.62; -0.50]),. Correlation coefficients ranged from ρ =-0.25 (95 % CI = [-0.63; 0.12]) in lymphoma to ρ=-0.66 (95 % CI = [-0.85; -0.47]) in glioma. Other coefficients were as follows: ovarian cancer, ρ = -0.64 (95% CI = [-0.76; -0.52]); lung cancer, ρ = -0.63 (95 % CI = [-0.78; -0.48]); uterine cervical cancer, ρ = -0.57 (95 % CI = [-0.80; -0.34]); prostatic cancer, ρ = -0.56 (95 % CI = [-0.69; -0.42]); renal cell carcinoma, ρ = -0.53 (95 % CI = [-0.93; -0.13]); head and neck squamous cell carcinoma, ρ = -0.53 (95 % CI = [-0.74; -0.32]); breast cancer, ρ = -0.48 (95 % CI = [-0.74; -0.23]); and meningioma, ρ = -0.45 (95 % CI = [-0.73; -0.17]).
The Cardiff Acne Disability Index (CADI): linguistic and cultural validation in Serbian.

PubMed

Jankovic, Slavenka; Vukicevic, Jelica; Djordjevic, Sanja; Jankovic, Janko; Marinkovic, Jelena; Basra, Mohammad K A

2013-02-01

The aims of this study were to translate the Cardiff Acne Disability Index (CADI) into Serbian and to assess its validity and reliability in Serbian acne patients. The CADI was translated and linguistically validated into Serbian according to published guidelines. This version of CADI, along with the Serbian version of Children's Dermatology Life Quality Index (CDLQI) and a short demographic questionnaire, was administrated to a cohort of secondary school pupils. The Global Acne Grading Score was used to measure the clinical severity of acne. The internal consistency reliability of the Serbian version of CADI was assessed by Cronbach's alpha coefficient while its concurrent validity was assessed by Spearman's correlation coefficient. Construct validity was examined by factor analysis. A total of 465 pupils completed questionnaires. Self-reported acne was present in 76% of pupils (353/465). The Serbian version of CADI showed high internal consistency reliability (Cronbach's alpha coefficient = 0.79). The mean item-total correlation coefficient was 0.74 with a range of 0.53-0.81. The concurrent validity of the scale was supported by a moderate but highly significant correlation with the CDLQI (Spearman's rho = 0.66; P < 0.001). Factor analysis revealed the presence of two dimensions underlying the factor structure of the scale. The Serbian version of the CADI is a reliable, valid, and valuable tool for assessing the impact of acne on the quality of life of Serbian-speaking patients.
Validation of Turkish version of brief negative symptom scale.

PubMed

Polat Nazlı, Irmak; Ergül, Ceylan; Aydemir, Ömer; Chandhoke, Swati; Üçok, Alp; Gönül, Ali Saffet

2016-11-01

Negative symptoms in schizophrenia have been assessed by many instruments. However, a current consensus on these symptoms has been built and new tools, such as the Brief Negative Symptom Scale (BNSS), are generated. This study aimed to evaluate reliability and validity of the Turkish version of BNSS. The scale was translated to Turkish and backtranslated to English. After the approval of the translation, 75 schizophrenia patients were interviewed with BNSS, Positive and Negative Syndrome Scale (PANSS), Calgary Depression Scale for Schizophrenia (CDSS) and Extrapyramidal Symptom Rating Scale (ESRS). Reliability and validity analyses were then calculated. In the reliability analysis, the Cronbach's alpha coefficient was 0.96 and item-total score correlation coefficients were between 0.655-0.884. The intraclass correlation coefficient was 0.665. The inter-rater reliability was 0.982 (p < 0.0001). In the validity analysis, the total score of BNSS-TR was correlated with PANSS Total Score, Positive Symptoms Subscale, Negative Symptoms Subscale, and General Psychopathology Subscale. CDSS and ESRS were not correlated with BNSS-TR. The factor structure of the scale was consisting the same items as in the original version. Our study confirms that the Turkish version of BNSS is an applicable tool for the evaluation of negative symptoms in schizophrenia.
Cross-cultural adaptation and validation of the Turkish version of Oxford hip score.

PubMed

Tuğay, Baki Umut; Tuğay, Nazan; Güney, Hande; Hazar, Zeynep; Yüksel, İnci; Atilla, Bülent

2015-06-01

The purpose of this study was to translate the Oxford hip score (OHS) into Turkish and to evaluate the psychometric properties by testing the internal consistency, reproducibility, construct validity, and responsiveness in patients with hip osteoarthritis (OA). Oxford hip score was translated and culturally adapted according to the guidelines in the literature. Seventy patients (mean age 61.45 ± 9.29 years) with hip osteoarthritis participated in the study. Patients completed the Turkish Oxford hip score (OHS-TR), the Short-Form 36 (SF-36), and Western Ontario and McMaster Universities Index (WOMAC). Internal consistency was tested using Cronbach's α coefficient. Patients completed OHS-TR questionnaire twice in 7 days for determining the reproducibility. Correlation between the total results of both tests was determined by the Pearson correlation coefficient and intraclass correlation coefficient (ICC). Validity was assessed by calculating the Pearson correlation coefficient between the OHS-TR and WOMAC and SF-36 scores. Floor and ceiling effects were analyzed. The internal consistency was high (Cronbach's α 0.93). The construct validity showed a significant correlation between the OHS-TR and WOMAC and related SF-36 domains (p < 0.001). The ICC's ranged between 0.80 and 0.99. There was no floor or ceiling effect in total OHS-TR score. The OHS-TR questionnaire is valid, reliable, and responsive for the Turkish-speaking patients with hip OA.
Quality assessment of remote sensing image fusion using feature-based fourth-order correlation coefficient

NASA Astrophysics Data System (ADS)

Ma, Dan; Liu, Jun; Chen, Kai; Li, Huali; Liu, Ping; Chen, Huijuan; Qian, Jing

2016-04-01

In remote sensing fusion, the spatial details of a panchromatic (PAN) image and the spectrum information of multispectral (MS) images will be transferred into fused images according to the characteristics of the human visual system. Thus, a remote sensing image fusion quality assessment called feature-based fourth-order correlation coefficient (FFOCC) is proposed. FFOCC is based on the feature-based coefficient concept. Spatial features related to spatial details of the PAN image and spectral features related to the spectrum information of MS images are first extracted from the fused image. Then, the fourth-order correlation coefficient between the spatial and spectral features is calculated and treated as the assessment result. FFOCC was then compared with existing widely used indices, such as Erreur Relative Globale Adimensionnelle de Synthese, and quality assessed with no reference. Results of the fusion and distortion experiments indicate that the FFOCC is consistent with subjective evaluation. FFOCC significantly outperforms the other indices in evaluating fusion images that are produced by different fusion methods and that are distorted in spatial and spectral features by blurring, adding noise, and changing intensity. All the findings indicate that the proposed method is an objective and effective quality assessment for remote sensing image fusion.
Threshold network of a financial market using the P-value of correlation coefficients

NASA Astrophysics Data System (ADS)

Ha, Gyeong-Gyun; Lee, Jae Woo; Nobi, Ashadun

2015-06-01

Threshold methods in financial networks are important tools for obtaining important information about the financial state of a market. Previously, absolute thresholds of correlation coefficients have been used; however, they have no relation to the length of time. We assign a threshold value depending on the size of the time window by using the P-value concept of statistics. We construct a threshold network (TN) at the same threshold value for two different time window sizes in the Korean Composite Stock Price Index (KOSPI). We measure network properties, such as the edge density, clustering coefficient, assortativity coefficient, and modularity. We determine that a significant difference exists between the network properties of the two time windows at the same threshold, especially during crises. This implies that the market information depends on the length of the time window when constructing the TN. We apply the same technique to Standard and Poor's 500 (S&P500) and observe similar results.
Hair cortisol detection in dairy cattle by using EIA: protocol validation and correlation with faecal cortisol metabolites.

PubMed

Tallo-Parra, O; Manteca, X; Sabes-Alsina, M; Carbajal, A; Lopez-Bejar, M

2015-06-01

Hair may be a useful matrix to detect cumulative cortisol concentrations in studies of animal welfare and chronic stress. The aim of this study was to validate a protocol for cortisol detection in hair from dairy cattle by enzyme immunoassay (EIA). Seventeen adult Holstein-Friesian dairy cows were used during the milking period. Hair cortisol concentration was assessed in 25-day-old hair samples taken from the frontal region of the head, analysing black and white coloured hair separately. Concentrations of cortisol metabolites were determined in faeces collected twice a week during the same period of time. There was a high correlation between cortisol values in faeces and cortisol in white colour hair samples but such correlation was not significant with the black colour hair samples. The intra- and inter-assay coefficients of variation were 4.9% and 10.6%, respectively. The linearity showed R 2=0.98 and mean percentage error of -10.8 ± 1.55%. The extraction efficiency was 89.0 ± 23.52% and the parallelism test showed similar slopes. Cortisol detection in hair by using EIA seems to be a valid method to represent long-term circulating cortisol levels in dairy cattle.
On the relationship between cumulative correlation coefficients and the quality of crystallographic data sets.

PubMed

Wang, Jimin; Brudvig, Gary W; Batista, Victor S; Moore, Peter B

2017-12-01

In 2012, Karplus and Diederichs demonstrated that the Pearson correlation coefficient CC 1/2 is a far better indicator of the quality and resolution of crystallographic data sets than more traditional measures like merging R-factor or signal-to-noise ratio. More specifically, they proposed that CC 1/2 be computed for data sets in thin shells of increasing resolution so that the resolution dependence of that quantity can be examined. Recently, however, the CC 1/2 values of entire data sets, i.e., cumulative correlation coefficients, have been used as a measure of data quality. Here, we show that the difference in cumulative CC 1/2 value between a data set that has been accurately measured and a data set that has not is likely to be small. Furthermore, structures obtained by molecular replacement from poorly measured data sets are likely to suffer from extreme model bias. © 2017 The Protein Society.
[Reliability and Validity of the Scale for Homophobia in Medicine Students].

PubMed

Campo-Arias, Adalberto; Lafaurie, María Mercedes; Gaitán-Duarte, Hernando G

2012-12-01

There are several scales to quantify homophobia in different populations. However, the reliability and validity of these instruments among Colombian students are unknown. Consequently, this work is intended to assess reliability (inner consistency) as well as the validity of the Scale for Homophobia in Medicine students from a private university in Bogotá (Colombia). Methodological study with 199 Medicine students from 1st to 5th semester that filled out the Homophobia Scale form, the general welfare questionnaire, the Attitude Towards Gays and Lesbians Scale (ATGL), WHO-5 (divergent validity) and the Francis Scale of Attitude Toward Christianity (nomologic validity). Pearson's correlations were computed, the Cronbach's alfa coefficient, the omega coefficient (construct's reliability) and confirmatory factorial analysis. The Scale for Homophobia showed an alpha Cronbach coefficient of 0,785, an omega coefficient of 0,790 and a Pearson correlation with the ATGL of 0,844; with WHO-5, -0,059; and a Francis Scale of Attitude Toward Christianity, 0,187. The Scale toward Homophobia exhibited a relevant factor of 44,7% of the total variance. The Scale for Homophobia showed acceptable reliability and validity. New studies should investigate the stability of the scale and the nomologic validity regarding other constructs. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.
aCORN: An experiment to measure the electron-antineutrino correlation coefficient in free neutron decay.

PubMed

Collett, B; Bateman, F; Bauder, W K; Byrne, J; Byron, W A; Chen, W; Darius, G; DeAngelis, C; Dewey, M S; Gentile, T R; Hassan, M T; Jones, G L; Komives, A; Laptev, A; Mendenhall, M P; Nico, J S; Noid, G; Park, H; Stephenson, E J; Stern, I; Stockton, K J S; Trull, C; Wietfeldt, F E; Yerozolimsky, B G

2017-08-01

We describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. Details of the method, apparatus, detectors, data acquisition, and data reduction scheme are presented, along with a discussion of the important systematic effects.
Partition coefficients of organic compounds in lipid-water systems and correlations with fish bioconcentration factors

USGS Publications Warehouse

Chiou, C.T.

1985-01-01

Triolein-water partition coefficients (KtW) have been determined for 38 slightly water-soluble organic compounds, and their magnitudes have been compared with the corresponding octanol-water partition coefficients (KOW). In the absence of major solvent-solute interaction effects in the organic solvent phase, the conventional treatment (based on Raoult's law) predicts sharply lower partition coefficients for most of the solutes in triolein because of its considerably higher molecular weight, whereas the Flory-Huggins treatment predicts higher partition coefficients with triolein. The data are in much better agreement with the Flory-Huggins model. As expected from the similarity in the partition coefficients, the water solubility (which was previously found to be the major determinant of the KOW) is also the major determinant for the Ktw. When the published BCF values (bioconcentration factors) of organic compounds in fish are based on the lipid content rather than on total mass, they are approximately equal to the Ktw, which suggests at least near equilibrium for solute partitioning between water and fish lipid. The close correlation between Ktw and Kow suggests that Kow is also a good predictor for lipid-water partition coefficients and bioconcentration factors.
Translation, cross-cultural adaptation and validation of the Bulgarian version of the Dizziness Handicap Inventory.

PubMed

Georgieva-Zhostova, Spaska; Kolev, Ognyan I; Stambolieva, Katerina

2014-09-01

The aim of the present study was the translation, cross-cultural adaptation and validation of the Dizziness Handicap Inventory in Bulgarian language (DHI-BG). Ninety-seven vestibular patients (19 men and 78 women, mean age 45.08 ± 13.85 years) took part in the investigation. All participants were asked to fill in the DHI-BG. Internal consistency was estimated using Cronbach's alpha and item-total correlation, reproducibility by calculating Bland-Altman's limits of agreement and intraclass correlation coefficients (ICCs). Associations were estimated by Spearman's correlation coefficients. The Cronbach's alpha for the total score, functional, physical and emotional subscales of DHI-BG were 0.88, 0.75, 0.72 and 0.81. The floor and ceiling effects of the DHI-BG total scale were evaluated with respect to the limits of agreement which were ±9.4-14.53 points. Intraclass correlation coefficients (ICCs) for all scale and subscales were higher than the recommended value of 0.75 and determined good test-retest reliability. The range of items correlation for DHI-BG was from 0.27 (item 12) to 0.72 (item 3). No significant differences were observed in the Cronbach's alpha coefficients between the DHI-BG and the original version, the German and Italian versions of the questionnaire. The most significant difference was observed in comparison with the German version of DHI. Construct validity presented a moderate correlation between Romberg coefficients and DHI-BG scores and strong correlation between all scores of DHI and the self-perceived disability. The results suggest that DHI-BG scores show a good discriminative validity between groups with different levels of self-assessed disability. The Bulgarian version of the DHI is a reliable and valid tool in assessing the impact of dizziness on the quality of life in Bulgarian vestibular patients.
aCORN: An experiment to measure the electron-antineutrino correlation coefficient in free neutron decay

DOE PAGES

Collett, B.; Bateman, F.; Bauder, W. K.; ...

2017-08-01

Here, we describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. This apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. We present details of the method, apparatus, detectors, data acquisition, and data reduction scheme, along with a discussion of the important systematic effects.
aCORN: An experiment to measure the electron-antineutrino correlation coefficient in free neutron decay

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collett, B.; Bateman, F.; Bauder, W. K.

Here, we describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. This apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. We present details of the method, apparatus, detectors, data acquisition, and data reduction scheme, along with a discussion of the important systematic effects.
[Correlation coefficient-based principle and method for the classification of jump degree in hydrological time series].

PubMed

Wu, Zi Yi; Xie, Ping; Sang, Yan Fang; Gu, Hai Ting

2018-04-01

The phenomenon of jump is one of the importantly external forms of hydrological variabi-lity under environmental changes, representing the adaption of hydrological nonlinear systems to the influence of external disturbances. Presently, the related studies mainly focus on the methods for identifying the jump positions and jump times in hydrological time series. In contrast, few studies have focused on the quantitative description and classification of jump degree in hydrological time series, which make it difficult to understand the environmental changes and evaluate its potential impacts. Here, we proposed a theatrically reliable and easy-to-apply method for the classification of jump degree in hydrological time series, using the correlation coefficient as a basic index. The statistical tests verified the accuracy, reasonability, and applicability of this method. The relationship between the correlation coefficient and the jump degree of series were described using mathematical equation by derivation. After that, several thresholds of correlation coefficients under different statistical significance levels were chosen, based on which the jump degree could be classified into five levels: no, weak, moderate, strong and very strong. Finally, our method was applied to five diffe-rent observed hydrological time series, with diverse geographic and hydrological conditions in China. The results of the classification of jump degrees in those series were closely accorded with their physically hydrological mechanisms, indicating the practicability of our method.
SPSS and SAS programs for comparing Pearson correlations and OLS regression coefficients.

PubMed

Weaver, Bruce; Wuensch, Karl L

2013-09-01

Several procedures that use summary data to test hypotheses about Pearson correlations and ordinary least squares regression coefficients have been described in various books and articles. To our knowledge, however, no single resource describes all of the most common tests. Furthermore, many of these tests have not yet been implemented in popular statistical software packages such as SPSS and SAS. In this article, we describe all of the most common tests and provide SPSS and SAS programs to perform them. When they are applicable, our code also computes 100 × (1 - α)% confidence intervals corresponding to the tests. For testing hypotheses about independent regression coefficients, we demonstrate one method that uses summary data and another that uses raw data (i.e., Potthoff analysis). When the raw data are available, the latter method is preferred, because use of summary data entails some loss of precision due to rounding.
Computational Fluid Dynamics Based Extraction of Heat Transfer Coefficient in Cryogenic Propellant Tanks

NASA Technical Reports Server (NTRS)

Yang, H. Q.; West, Jeff

2015-01-01

Current reduced-order thermal model for cryogenic propellant tanks is based on correlations built for flat plates collected in the 1950's. The use of these correlations suffers from: inaccurate geometry representation; inaccurate gravity orientation; ambiguous length scale; and lack of detailed validation. The work presented under this task uses the first-principles based Computational Fluid Dynamics (CFD) technique to compute heat transfer from tank wall to the cryogenic fluids, and extracts and correlates the equivalent heat transfer coefficient to support reduced-order thermal model. The CFD tool was first validated against available experimental data and commonly used correlations for natural convection along a vertically heated wall. Good agreements between the present prediction and experimental data have been found for flows in laminar as well turbulent regimes. The convective heat transfer between tank wall and cryogenic propellant, and that between tank wall and ullage gas were then simulated. The results showed that commonly used heat transfer correlations for either vertical or horizontal plate over predict heat transfer rate for the cryogenic tank, in some cases by as much as one order of magnitude. A characteristic length scale has been defined that can correlate all heat transfer coefficients for different fill levels into a single curve. This curve can be used for the reduced-order heat transfer model analysis.
Real-time measurement of volcanic SO2 emissions: Validation of a new UV correlation spectrometer (FLYSPEC)

USGS Publications Warehouse

Horton, Keith A.; Williams-Jones, Glyn; Garbeil, Harold; Elias, Tamar; Sutton, A. Jeff; Mouginis-Mark, Peter J; Porter, John T.; Clegg, Steven

2006-01-01

A miniaturized, lightweight and low-cost UV correlation spectrometer, the FLYSPEC, has been developed as an alternative for the COSPEC, which has long been the mainstay for monitoring volcanic sulfur dioxide fluxes. Field experiments have been conducted with the FLYSPEC at diverse volcanic systems, including Masaya (Nicaragua), Poás (Costa Rica), Stromboli, Etna and Vulcano (Italy), Villarica (Chile) and Kilauea (USA). We present here those validation measurements that were made simultaneously with COSPEC at Kilauea between March 2002 and February 2003. These experiments, with source emission rates that ranged from 95 to 1,560 t d−1, showed statistically identical results from both instruments. SO2 path-concentrations ranged from 0 to >1,000 ppm-m with average correlation coefficients greater than r2=0.946. The small size and low cost create the opportunity for FLYSPEC to be used in novel deployment modes that have the potential to revolutionize the manner in which volcanic and industrial monitoring is performed.
Reliability and concurrent validity of the adapted Chinese version of Scoliosis Research Society-22 (SRS-22) questionnaire.

PubMed

Cheung, Kenneth M C; Senkoylu, Alpaslan; Alanay, Ahmet; Genc, Yasemin; Lau, Sarah; Luk, Keith D

2007-05-01

Validation study to define validity and reliability of an adapted and translated questionnaire. Assessment of the concurrent validity and reliability of a Chinese version of SRS-22 outcome instrument. No valid health-related quality of life (HRQL) outcome instrument exists for patients with spinal deformity in Chinese. The modified SRS-22 questionnaire was proven to be an appropriate outcome instrument in English, and has already been translated and validated in several other languages. The English version of the SRS-22 questionnaire was adapted to Chinese according to the International Quality of Life Assessment Project guidelines. To assess reliability, 48 subjects with adolescent idiopathic scoliosis (mean age, 16.5 years) filled the questionnaire on 2 separate occasions (Group 1). To assess concurrent validity, 50 subjects (mean age, 21 years) filled in the same questionnaire and a previously validated Chinese version of the Short Form-36 (SF36) questionnaire (Group 2). Internal consistency, reproducibility and concurrent validity were determined with Cronbach's alpha coefficient, interclass correlation coefficient and Pearson correlation coefficient, respectively. Cronbach's alpha coefficient for the 4 major domains (function/activity, pain, self-image/appearance and mental health) were high. Intraclass correlation was also excellent for all domains. For concurrent validity, excellent correlation was found in 1 domain, good in 12 domains, moderate in 3 domains, and poor in 1 domain of the 17 relevant domains. Both cultural adaptation and linguistic translation are essential in any attempt to use a HRQL questionnaire across cultures. The Chinese version of the SRS-22 outcome instrument has satisfactory internal consistency and excellent reproducibility. It is ready for use in clinical studies on idiopathic scoliosis in Chinese-speaking societies.

Validity of three clinical performance assessments of internal medicine clerks.

PubMed

Hull, A L; Hodder, S; Berger, B; Ginsberg, D; Lindheim, N; Quan, J; Kleinhenz, M E

1995-06-01

To analyze the construct validity of three methods to assess the clinical performances of internal medicine clerks. A multitrait-multimethod (MTMM) study was conducted at the Case Western Reserve University School of Medicine to determine the convergent and divergent validity of a clinical evaluation form (CEF) completed by faculty and residents, an objective structured clinical examination (OSCE), and the medicine subject test of the National Board of Medical Examiners. Three traits were involved in the analysis: clinical skills, knowledge, and personal characteristics. A correlation matrix was computed for 410 third-year students who completed the clerkship between August 1988 and July 1991. There was a significant (p < .01) convergence of the four correlations that assessed the same traits by using different methods. However, the four convergent correlations were of moderate magnitude (ranging from .29 to .47). Divergent validity was assessed by comparing the magnitudes of the convergence correlations with the magnitudes of correlations among unrelated assessments (i.e., different traits by different methods). Seven of nine possible coefficients were smaller than the convergent coefficients, suggesting evidence of divergent validity. A significant CEF method effect was identified. There was convergent validity and some evidence of divergent validity with a significant method effect. The findings were similar for correlations corrected for attenuation. Four conclusions were reached: (1) the reliability of the OSCE must be improved, (2) the CEF ratings must be redesigned to further discriminate among the specific traits assessed, (3) additional methods to assess personal characteristics must be instituted, and (4) several assessment methods should be used to evaluate individual student performances.
Technical characterization of dialysis fluid flow and mass transfer rate in dialyzers with various filtration coefficients using dimensionless correlation equation.

PubMed

Fukuda, Makoto; Yoshimura, Kengo; Namekawa, Koki; Sakai, Kiyotaka

2017-06-01

The objective of the present study is to evaluate the effect of filtration coefficient and internal filtration on dialysis fluid flow and mass transfer coefficient in dialyzers using dimensionless mass transfer correlation equations. Aqueous solution of vitamin B 12 clearances were obtained for REXEED-15L as a low flux dialyzer, and APS-15EA and APS-15UA as high flux dialyzers. All the other design specifications were identical for these dialyzers except for filtration coefficient. The overall mass transfer coefficient was calculated, moreover, the exponents of Reynolds number (Re) and film mass transfer coefficient of the dialysis-side fluid (k D ) for each flow rate were derived from the Wilson plot and dimensionless correlation equation. The exponents of Re were 0.4 for the low flux dialyzer whereas 0.5 for the high flux dialyzers. Dialysis fluid of the low flux dialyzer was close to laminar flow because of its low filtration coefficient. On the other hand, dialysis fluid of the high flux dialyzers was assumed to be orthogonal flow. Higher filtration coefficient was associated with higher k D influenced by mass transfer rate through diffusion and internal filtration. Higher filtration coefficient of dialyzers and internal filtration affect orthogonal flow of dialysis fluid.
Simultaneous characterization of lateral lipid and prothrombin diffusion coefficients by z-scan fluorescence correlation spectroscopy.

PubMed

Stefl, Martin; Kułakowska, Anna; Hof, Martin

2009-08-05

A new (to our knowledge) robust approach for the determination of lateral diffusion coefficients of weakly bound proteins is applied for the phosphatidylserine specific membrane interaction of bovine prothrombin. It is shown that z-scan fluorescence correlation spectroscopy in combination with pulsed interleaved dual excitation allows simultaneous monitoring of the lateral diffusion of labeled protein and phospholipids. Moreover, from the dependencies of the particle numbers on the axial sample positions at different protein concentrations phosphatidylserine-dependent equilibrium dissociation constants are derived confirming literature values. Increasing the amount of membrane-bound prothrombin retards the lateral protein and lipid diffusion, indicating coupling of both processes. The lateral diffusion coefficients of labeled lipids are considerably larger than the simultaneously determined lateral diffusion coefficients of prothrombin, which contradicts findings reported for the isolated N-terminus of prothrombin.
[Prediction of soil adsorption coefficients of organic compounds in a wide range of soil types by soil column liquid chromatography].

PubMed

Guo, Rongbo; Chen, Jiping; Zhang, Qing; Wu, Wenzhong; Liang, Xinmiao

2004-01-01

Using the methanol-water mixtures as mobile phases of soil column liquid chromatography (SCLC), prediction of soil adsorption coefficients (K(d)) by SCLC was validated in a wide range of soil types. The correlations between the retention factors measured by SCLC and soil adsorption coefficients measured by batch experiments were studied for five soils with different properties, i.e., Eurosoil 1#, 2#, 3#, 4# and 5#. The results show that good correlations existed between the retention factors and soil adsorption coefficients for Eurosoil 1#, 2#, 3# and 4#. For Eurosoil 5# which has a pH value of near 3, the correlation between retention factors and soil adsorption coefficients was unsatisfactory using methanol-water as mobile phase of SCLC. However, a good correlation was obtained using a methanol-buffer mixture with pH 3 as the mobile phase. This study proved that the SCLC is suitable for the prediction of soil adsorption coefficients.
Determination and importance of temperature dependence of retention coefficient (RPHPLC) in QSAR model of nitrazepams' partition coefficient in bile acid micelles.

PubMed

Posa, Mihalj; Pilipović, Ana; Lalić, Mladena; Popović, Jovan

2011-02-15

Linear dependence between temperature (t) and retention coefficient (k, reversed phase HPLC) of bile acids is obtained. Parameters (a, intercept and b, slope) of the linear function k=f(t) highly correlate with bile acids' structures. Investigated bile acids form linear congeneric groups on a principal component (calculated from k=f(t)) score plot that are in accordance with conformations of the hydroxyl and oxo groups in a bile acid steroid skeleton. Partition coefficient (K(p)) of nitrazepam in bile acids' micelles is investigated. Nitrazepam molecules incorporated in micelles show modified bioavailability (depo effect, higher permeability, etc.). Using multiple linear regression method QSAR models of nitrazepams' partition coefficient, K(p) are derived on the temperatures of 25°C and 37°C. For deriving linear regression models on both temperatures experimentally obtained lipophilicity parameters are included (PC1 from data k=f(t)) and in silico descriptors of the shape of a molecule while on the higher temperature molecular polarisation is introduced. This indicates the fact that the incorporation mechanism of nitrazepam in BA micelles changes on the higher temperatures. QSAR models are derived using partial least squares method as well. Experimental parameters k=f(t) are shown to be significant predictive variables. Both QSAR models are validated using cross validation and internal validation method. PLS models have slightly higher predictive capability than MLR models. Copyright © 2010 Elsevier B.V. All rights reserved.
Quality-of-life in insect venom allergy: validation of the Turkish version of the "Vespid Allergy Quality of Life Questionnaire" (VQLQ-T).

PubMed

Sin, Betül Ayşe; Öztuna, Derya; Gelincik, Aslı; Gürlek, Feridun; Baysan, Abdullah; Sin, Aytül Zerrin; Aydın, Ömür; Mısırlıgil, Zeynep

2016-01-01

"Vespid Allergy Quality of Life Questionnaire (VQLQ)" has been used to assess psychological burden of disease. The aim of this study was to evaluate validity, reliability and responsiveness to interventions of the Turkish version. The Turkish language Questionnaire (VQLQ-T) was administered to 81 patients with bee allergy and 65 patients with vespid allergy from different groups to achieve cross-sectional validation. To establish longitudinal validity, the questionnaire was administered to 36 patients treated with venom immunotherapy. The cross-sectional validation in patients with vespid venom allergy showed a correlation coefficient of 0.97 (Cronbach α). Spearman's correlation coefficient of the pretreatment VQLQ-T score with Expectation of Outcome (EoO) questionnaire score was 0.55 (p < 0.001). After treatment, correlation between VQLQ-T score and EoO score was 0.64 (p = 0.003) in these patients. The cross-sectional instrument validation for non-beekeepers with bee venom allergy yielded a correlation coefficient of 0.96 (Cronbach α). Spearman's correlation coefficient between pretreatment VQLQ-T score and EoO score was 0.47 (p < 0.001) and after treatment, correlation between VQLQ-T score and EoO score was 0.78 (p = 0.008) in these patients. These findings indicate cross-sectional validity of VQLQ-T. In the longitudinal validation, there was a positive correlation between EoO and VQLQ-T with a correlation coefficient of 0.562 (p < 0.001). While mean (±SD) VQLQ-T score was 5.27 (±1.29) in pretreatment, it was 2.78 (±1.01) after treatment (p < 0.001). The correlation between the mean change in VQLQ-T score and the mean change in EoO score was 0.42 (p = 0.011). The Turkish version of VQLQ-T enables measurement of Quality of Life (QoL) in patients with either vespid or bee venom allergy. Furthermore, responsiveness of this instrument demonstrates the questionnaire's ability to detect changes over time.
AN EMPIRICAL INVESTIGATION OF THE EFFECTS OF NONNORMALITY UPON THE SAMPLING DISTRIBUTION OF THE PROJECT MOMENT CORRELATION COEFFICIENT.

ERIC Educational Resources Information Center

HJELM, HOWARD; NORRIS, RAYMOND C.

THE STUDY EMPIRICALLY DETERMINED THE EFFECTS OF NONNORMALITY UPON SOME SAMPLING DISTRIBUTIONS OF THE PRODUCT MOMENT CORRELATION COEFFICIENT (PMCC). SAMPLING DISTRIBUTIONS OF THE PMCC WERE OBTAINED BY DRAWING NUMEROUS SAMPLES FROM CONTROL AND EXPERIMENTAL POPULATIONS HAVING VARIOUS DEGREES OF NONNORMALITY AND BY CALCULATING CORRELATION COEFFICIENTS…
American Orthopaedic Foot and Ankle Society ankle-hindfoot scale: A cross-cultural adaptation and validation study from Iran.

PubMed

Vosoughi, Amir Reza; Roustaei, Narges; Mahdaviazad, Hamideh

2018-06-01

The use of valid and reliable outcome rating scales is essential for evaluating the result of different treatments and interventions. The purposes of this study were to translate and culturally adapt the American Orthopaedic Foot and Ankle Society ankle-hindfoot scale (AOFAS-AHFS) into Persian languages and evaluate its psychometric properties. Forward-backward translation and cultural adaptation method were used to develop Persian version of AOFAS-AHFS. From March to July 2016, one hundred consecutive patients with ankle and hindfoot injuries were included. Internal consistency and reproducibility were evaluated using Cronbach's alpha, Spearman's rank correlation coefficient and Intraclass correlation coefficient (ICC) respectively. Construct validity reported which compare the outcome rating scale measurements with Short Form-36 (SF-36), also convergent and discriminant validity evaluated using Spearman's rank correlation coefficient. Mean age (SD) of the patients was 41.95±13.45years. Cronbach's α coefficient, Spearman's rho and ICC values were 0.71, 0.89 and 0.90 respectively. Total score of AOFAS-AHFS and SF-36 domains has a correlation ranged between 0.17-0.55. Spearman's rank correlation coefficient of 0.4 was exceeded by all items with the exception of stability. The Spearman's rank correlation between each item in functional subscales with its own subscales was higher than the correlation between these items and other subscales. Persian version of AOFAS-AHFS provides additional reliable and valid instrument which can be used to assess broad range of patients with foot and ankle disorders that speaking in Persian. However, it seems that the original version of AOFAS-AHFS needs some revisions. Copyright © 2017 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.
Correlation between Mechanical Properties with Specific Wear Rate and the Coefficient of Friction of Graphite/Epoxy Composites

PubMed Central

Alajmi, Mahdi; Shalwan, Abdullah

2015-01-01

The correlation between the mechanical properties of Fillers/Epoxy composites and their tribological behavior was investigated. Tensile, hardness, wear, and friction tests were conducted for Neat Epoxy (NE), Graphite/Epoxy composites (GE), and Data Palm Fiber/Epoxy with or without Graphite composites (GFE and FE). The correlation was made between the tensile strength, the modulus of elasticity, elongation at the break, and the hardness, as an individual or a combined factor, with the specific wear rate (SWR) and coefficient of friction (COF) of composites. In general, graphite as an additive to polymeric composite has had an eclectic effect on mechanical properties, whereas it has led to a positive effect on tribological properties, whilst date palm fibers (DPFs), as reinforcement for polymeric composite, promoted a mechanical performance with a slight improvement to the tribological performance. Statistically, this study reveals that there is no strong confirmation of any marked correlation between the mechanical and the specific wear rate of filler/Epoxy composites. There is, however, a remarkable correlation between the mechanical properties and the friction coefficient of filler/Epoxy composites. PMID:28793431
Correlation between Mechanical Properties with Specific Wear Rate and the Coefficient of Friction of Graphite/Epoxy Composites.

PubMed

Alajmi, Mahdi; Shalwan, Abdullah

2015-07-08

The correlation between the mechanical properties of Fillers/Epoxy composites and their tribological behavior was investigated. Tensile, hardness, wear, and friction tests were conducted for Neat Epoxy (NE), Graphite/Epoxy composites (GE), and Data Palm Fiber/Epoxy with or without Graphite composites (GFE and FE). The correlation was made between the tensile strength, the modulus of elasticity, elongation at the break, and the hardness, as an individual or a combined factor, with the specific wear rate (SWR) and coefficient of friction (COF) of composites. In general, graphite as an additive to polymeric composite has had an eclectic effect on mechanical properties, whereas it has led to a positive effect on tribological properties, whilst date palm fibers (DPFs), as reinforcement for polymeric composite, promoted a mechanical performance with a slight improvement to the tribological performance. Statistically, this study reveals that there is no strong confirmation of any marked correlation between the mechanical and the specific wear rate of filler/Epoxy composites. There is, however, a remarkable correlation between the mechanical properties and the friction coefficient of filler/Epoxy composites.
The analysis of reliability and validity of the IT-MAIS, MAIS and MUSS.

PubMed

Zhong, Yan; Xu, Tianqiu; Dong, Ruijuan; Lyu, Jing; Liu, Bo; Chen, Xueqing

2017-05-01

The aim of this study was to investigate the reliability and validity of the Infant-toddler Meaningful Auditory Integration Scale (IT-MAIS), Meaningful Auditory Integration Scale (MAIS), and Meaningful Use of Speech Scale (MUSS). IT-MAIS, MAIS and MUSS were divided into 3 sub dimensions. 300 children with cochlear implants (CI) were included in the investigation. To assess test-retest reliability of these questionnaires, 30 children were selected randomly to be evaluated at a two-week interval indicated that there were no significant changes between test and retest. Furthermore random test analysis by different evaluators was also administered to 30 users. Reliability test: Test-retest reliability of the three scales was proved to be satisfactory. All domains had correlation coefficients that exceeded 0.750(P < 0.01). The Cronbach's α of the three scales and their three domains were greater than 0.700. Reliability between evaluators of the three scales were considered to be satisfactory. All domains had correlation coefficients that exceeded 0.750(P < 0.01). Validity test: The evaluation of content validity by expert review showed the questionnaire had good content validity; The correlation coefficients between the overall scores of the three scales and their three domains were 0.699-0.978(P < 0.01). There were correlations among the three sub-domains but the strength of the correlations was relatively low. There was certain construct validity. IT-MAIS, MAIS, MUSS scales have good reliability and validity, and can be used to measure the outcome for children with cochlear implants hearing and speech evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.
Validation of the Turkish version of the Breast Reduction Assessed Severity Scale.

PubMed

Kececi, Yavuz; Sir, Emin; Zengel, Baha

2013-01-01

Measuring patient-reported outcomes has become increasingly important in cosmetic and reconstructive breast surgery. There is no validated questionnaire in Turkish to evaluate quality-of-life issues for patients with mammary hypertrophy. The authors describe the reliability and validity of a translated Breast Reduction Assessed Severity Scale (BRASS) in evaluating Turkish patients. The BRASS, developed by Sigurdson et al, was translated into Turkish adhering strictly to the guidelines of questionnaire translations. Statistical analysis was carried out with Cronbach's α to test the internal consistency and intraclass correlation coefficient for test-retest reliability. Exploratory factor analysis was carried out using principal component analysis with oblimin rotation to test its construct validity. Correlations between subscales identified in the factor analysis and corresponding domains in the Short Form-36 and Rosenberg Self-Esteem Scale were analyzed. The total instrument was found to have an α coefficient of 0.92 and subscale α coefficients ranging from 0.76 to 0.87. Intraclass correlation coefficient was 0.93 for the total scale and ranged from 0.81 to 0.91 for the subscales. Exploratory factor analysis resulted in a 5-factor structure: physical implications, body pain, physical appearance, poor self-concept, and negative social interactions. With this study, the reliability and validity of the Turkish version of the BRASS were revealed. This translated version can be used to evaluate the effect of mammary hypertrophy on quality of life in Turkish patients.
Validation of the Japanese version of the Pediatric Quality of Life Inventory (PedsQL) Cancer Module.

PubMed

Tsuji, Naoko; Kakee, Naoko; Ishida, Yasushi; Asami, Keiko; Tabuchi, Ken; Nakadate, Hisaya; Iwai, Tsuyako; Maeda, Miho; Okamura, Jun; Kazama, Takuro; Terao, Yoko; Ohyama, Wataru; Yuza, Yuki; Kaneko, Takashi; Manabe, Atsushi; Kobayashi, Kyoko; Kamibeppu, Kiyoko; Matsushima, Eisuke

2011-04-10

The PedsQL 3.0 Cancer Module is a widely used instrument to measure pediatric cancer specific health-related quality of life (HRQOL) for children aged 2 to 18 years. We developed the Japanese version of the PedsQL Cancer Module and investigated its reliability and validity among Japanese children and their parents. Participants were 212 children with cancer and 253 of their parents. Reliability was determined by internal consistency using Cronbach's coefficient alpha and test-retest reliability using intra-class correlation coefficient (ICC). Validity was assessed through factor validity, convergent and discriminant validity, concurrent validity, and clinical validity. Factor validity was examined by exploratory factor analysis. Convergent and discriminant validity were examined by multitrait scaling analysis. Concurrent validity was assessed using Spearman's correlation coefficients between the Cancer Module and Generic Core Scales, and the comparison of the scores of child self-reports with those of other self-rating depression scales for children. Clinical validity was assessed by comparing the on- and off- treatment scores using Kruskal-Wallis and Mann-Whitney U tests. Cronbach's coefficient alpha was over 0.70 for the total scale and over 0.60 for each subscale by age except for the 'pain and hurt' subscale for children aged 5 to 7 years. For test-retest reliability, the ICC exceeded 0.70 for the total scale for each age. Exploratory factor analysis demonstrated sufficient factorial validity. Multitrait scaling analysis showed high success rates. Strong correlations were found between the reports by children and their parents, and the scores of the Cancer Module and the Generic Core Scales except for 'treatment anxiety' subscales for child reports. The Depression Self-Rating Scale for Children (DSRS-C) scores were significantly correlated with emotional domains and the total score of the cancer module. Children who had been off treatment over 12 months
Reliability, Validity, and Cross-Cultural Adaptation of the Turkish Version of the Bournemouth Questionnaire.

PubMed

Gunaydin, Gurkan; Citaker, Seyit; Meray, Jale; Cobanoglu, Gamze; Gunaydin, Ozge Ece; Hazar Kanik, Zeynep

2016-11-01

Validation of a self-report questionnaire. The purpose of this study was to investigate adaptation, validity, and reliability of the Turkish version of the Bournemouth Questionnaire. Low back pain is one of the most frequent disorders leading to activity limitation. This pain affects most of people in their lives. The most important point to evaluate patient's functional abilities and to decide a successful therapy procedure is to manage the assessment questionnaires precisely. One hundred ten patients with chronic low back pain were included in present study. To assess reliability, test-retest and internal consistency analyses were applied. The results of test-retest analysis were assessed by using Intraclass Correlation Coefficient method (95% confidence interval). For internal consistency, Cronbach alpha value was calculated. Validity of the questionnaire was assessed in terms of construct validity. For construct validity, factor analysis and convergent validity were tested. For convergent validity, total points of the Bournemouth Questionnaire were assessed with the total points of Quebec Back Pain Disability Scale and Roland Morris Disability Questionnaire by using Pearson correlation coefficient analysis. Cronbach alpha value was found 0.914, showing that this questionnaire has high internal consistency. The results of test-retest analysis were varying between 0.851 and 0.927, which shows that test-retest results are highly correlated. Factor analysis test indicated that this questionnaire had one factor. Pearson correlation coefficient of the Bournemouth Questionnaire with Roland Morris Disability Questionnaire was calculated 0.703 and it was found with Quebec Back Pain Disability Scale is 0.659. These results showed that the Bournemouth Questionnaire is very good correlated with Roland Morris Disability Questionnaire and Quebec Back Pain Disability Scale. The Turkish version of the Bournemouth Questionnaire is valid and reliable. 3.
Intraclass Correlation Coefficients in Hierarchical Design Studies with Discrete Response Variables: A Note on a Direct Interval Estimation Procedure

ERIC Educational Resources Information Center

Raykov, Tenko; Marcoulides, George A.

2015-01-01

A latent variable modeling procedure that can be used to evaluate intraclass correlation coefficients in two-level settings with discrete response variables is discussed. The approach is readily applied when the purpose is to furnish confidence intervals at prespecified confidence levels for these coefficients in setups with binary or ordinal…
Validity and reliability of the Diagnostic Adaptive Behaviour Scale.

PubMed

Tassé, M J; Schalock, R L; Balboni, G; Spreat, S; Navas, P

2016-01-01

The Diagnostic Adaptive Behaviour Scale (DABS) is a new standardised adaptive behaviour measure that provides information for evaluating limitations in adaptive behaviour for the purpose of determining a diagnosis of intellectual disability. This article presents validity evidence and reliability data for the DABS. Validity evidence was based on comparing DABS scores with scores obtained on the Vineland Adaptive Behaviour Scale, second edition. The stability of the test scores was measured using a test and retest, and inter-rater reliability was assessed by computing the inter-respondent concordance. The DABS convergent validity coefficients ranged from 0.70 to 0.84, while the test-retest reliability coefficients ranged from 0.78 to 0.95, and the inter-rater concordance as measured by intraclass correlation coefficients ranged from 0.61 to 0.87. All obtained validity and reliability indicators were strong and comparable with the validity and reliability coefficients of the most commonly used adaptive behaviour instruments. These results and the advantages of the DABS for clinician and researcher use are discussed. © 2015 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.
Oxford Knee Score: cross-cultural adaptation and validation of the Turkish version in patients with osteoarthritis of the knee.

PubMed

Tuğay, Baki Umut; Tuğay, Nazan; Güney, Hande; Kınıklı, Gizem İrem; Yüksel, İnci; Atilla, Bülent

2016-01-01

The Oxford Knee Score (OKS) is a valid, short, self-administered, and site- specific outcome measure specifically developed for patients with knee arthroplasty. This study aimed to cross-culturally adapt and validate the OKS to be used in Turkish-speaking patients with osteoarthritis of the knee. The OKS was translated and culturally adapted according to the guidelines in the literature. Ninety-one patients (mean age: 55.89±7.85 years) with knee osteoarthritis participated in the study. Patients completed the Turkish version of the Oxford Knee Score (OKS-TR), Short-Form 36 Health Survey (SF-36), and Western Ontario and McMaster Universities Index (WOMAC) questionnaires. Internal consistency was tested using Cronbach's α coefficient. Patients completed the OKS-TR questionnaire twice in 7 days to determine the reproducibility. Correlation between the total results of both tests was determined by Spearman's correlation coefficient and intraclass correlation coefficients (ICC). Validity was assessed by calculating Spearman's correlation coefficient between the OKS, WOMAC, and SF-36 scores. Floor and ceiling effects were analyzed. Internal consistency was high (Cronbach's α: 0.90). The reproducibility tested by 2 different methods showed no significant difference (p>0.05). The construct validity analyses showed a significant correlation between the OKS and the other scores (p<0.05). There was no floor or ceiling effect in total OKS score. The OKS-TR is a reliable and valid measure for the self-assessment of pain and function in Turkish-speaking patients with osteoarthritis of the knee.
Validation study of an electronic method of condensed outcomes tools reporting in orthopaedics.

PubMed

Farr, Jack; Verma, Nikhil; Cole, Brian J

2013-12-01

Patient-reported outcomes (PRO) instruments are a vital source of data for evaluating the efficacy of medical treatments. Historically, outcomes instruments have been designed, validated, and implemented as paper-based questionnaires. The collection of paper-based outcomes information may result in patients becoming fatigued as they respond to redundant questions. This problem is exacerbated when multiple PRO measures are provided to a single patient. In addition, the management and analysis of data collected in paper format involves labor-intensive processes to score and render the data analyzable. Computer-based outcomes systems have the potential to mitigate these problems by reformatting multiple outcomes tools into a single, user-friendly tool.The study aimed to determine whether the electronic outcomes system presented produces results comparable with the test-retest correlations reported for the corresponding orthopedic paper-based outcomes instruments.The study is designed as a crossover study based on consecutive orthopaedic patients arriving at one of two designated orthopedic knee clinics.Patients were assigned to complete either a paper or a computer-administered questionnaire based on a similar set of questions (Knee injury and Osteoarthritis Outcome Score, International Knee Documentation Committee form, 36-Item Short Form survey, version 1, Lysholm Knee Scoring Scale). Each patient completed the same surveys using the other instrument, so that all patients had completed both paper and electronic versions. Correlations between the results from the two modes were studied and compared with test-retest data from the original validation studies.The original validation studies established test-retest reliability by computing correlation coefficients for two administrations of the paper instrument. Those correlation coefficients were all in the range of 0.7 to 0.9, which was deemed satisfactory. The present study computed correlation coefficients between
Validation of general job satisfaction in the Korean Labor and Income Panel Study.

PubMed

Park, Shin Goo; Hwang, Sang Hee

2017-01-01

The purpose of this study is to assess the validity and reliability of general job satisfaction (JS) in the Korean Labor and Income Panel Study (KLIPS). We used the data from the 17th wave (2014) of the nationwide KLIPS, which selected a representative panel sample of Korean households and individuals aged 15 or older residing in urban areas. We included in this study 7679 employed subjects (4529 males and 3150 females). The general JS instrument consisted of five items rated on a scale from 1 (strongly disagree) to 5 (strongly agree). The general JS reliability was assessed using the corrected item-total correlation and Cronbach's alpha coefficient. The validity of general JS was assessed using confirmatory factor analysis (CFA) and Pearson's correlation. The corrected item-total correlations ranged from 0.736 to 0.837. Therefore, no items were removed. Cronbach's alpha for general JS was 0.925, indicating excellent internal consistency. The CFA of the general JS model showed a good fit. Pearson's correlation coefficients for convergent validity showed moderate or strong correlations. The results obtained in our study confirm the validity and reliability of general JS.
Reliability and Validity of the Japanese Version of the Kinesthetic and Visual Imagery Questionnaire (KVIQ)

PubMed Central

Nakano, Hideki; Kodama, Takayuki; Ukai, Kazumasa; Kawahara, Satoru; Horikawa, Shiori; Murata, Shin

2018-01-01

In this study, we aimed to (1) translate the English version of the Kinesthetic and Visual Imagery Questionnaire (KVIQ), which assesses motor imagery ability, into Japanese, and (2) investigate the reliability and validity of the Japanese KVIQ. We enrolled 28 healthy adults in this study. We used Cronbach’s alpha coefficients to assess reliability reflected by the internal consistency. Additionally, we assessed validity reflected by the criterion-related validity between the Japanese KVIQ and the Japanese version of the Movement Imagery Questionnaire-Revised (MIQ-R) with Spearman’s rank correlation coefficients. The Cronbach’s alpha coefficients for the KVIQ-20 were 0.88 (Visual) and 0.91 (Kinesthetic), which indicates high reliability. There was a significant positive correlation between the Japanese KVIQ-20 (Total) and the Japanese MIQ-R (Total) (r = 0.86, p < 0.01). Our results suggest that the Japanese KVIQ is an assessment that is a reliable and valid index of motor imagery ability. PMID:29724042

Reliability and Validity of the Japanese Version of the Kinesthetic and Visual Imagery Questionnaire (KVIQ).

PubMed

Nakano, Hideki; Kodama, Takayuki; Ukai, Kazumasa; Kawahara, Satoru; Horikawa, Shiori; Murata, Shin

2018-05-02

In this study, we aimed to (1) translate the English version of the Kinesthetic and Visual Imagery Questionnaire (KVIQ), which assesses motor imagery ability, into Japanese, and (2) investigate the reliability and validity of the Japanese KVIQ. We enrolled 28 healthy adults in this study. We used Cronbach’s alpha coefficients to assess reliability reflected by the internal consistency. Additionally, we assessed validity reflected by the criterion-related validity between the Japanese KVIQ and the Japanese version of the Movement Imagery Questionnaire-Revised (MIQ-R) with Spearman’s rank correlation coefficients. The Cronbach’s alpha coefficients for the KVIQ-20 were 0.88 (Visual) and 0.91 (Kinesthetic), which indicates high reliability. There was a significant positive correlation between the Japanese KVIQ-20 (Total) and the Japanese MIQ-R (Total) (r = 0.86, p < 0.01). Our results suggest that the Japanese KVIQ is an assessment that is a reliable and valid index of motor imagery ability.
Estimating activity energy expenditure: how valid are physical activity questionnaires?

PubMed

Neilson, Heather K; Robson, Paula J; Friedenreich, Christine M; Csizmadi, Ilona

2008-02-01

Activity energy expenditure (AEE) is the modifiable component of total energy expenditure (TEE) derived from all activities, both volitional and nonvolitional. Because AEE may affect health, there is interest in its estimation in free-living people. Physical activity questionnaires (PAQs) could be a feasible approach to AEE estimation in large populations, but it is unclear whether or not any PAQ is valid for this purpose. Our aim was to explore the validity of existing PAQs for estimating usual AEE in adults, using doubly labeled water (DLW) as a criterion measure. We reviewed 20 publications that described PAQ-to-DLW comparisons, summarized study design factors, and appraised criterion validity using mean differences (AEE(PAQ) - AEE(DLW), or TEE(PAQ) - TEE(DLW)), 95% limits of agreement, and correlation coefficients (AEE(PAQ) versus AEE(DLW) or TEE(PAQ) versus TEE(DLW)). Only 2 of 23 PAQs assessed most types of activity over the past year and indicated acceptable criterion validity, with mean differences (TEE(PAQ) - TEE(DLW)) of 10% and 2% and correlation coefficients of 0.62 and 0.63, respectively. At the group level, neither overreporting nor underreporting was more prevalent across studies. We speculate that, aside from reporting error, discrepancies between PAQ and DLW estimates may be partly attributable to 1) PAQs not including key activities related to AEE, 2) PAQs and DLW ascertaining different time periods, or 3) inaccurate assignment of metabolic equivalents to self-reported activities. Small sample sizes, use of correlation coefficients, and limited information on individual validity were problematic. Future research should address these issues to clarify the true validity of PAQs for estimating AEE.
Application of the Gini correlation coefficient to infer regulatory relationships in transcriptome analysis.

PubMed

Ma, Chuang; Wang, Xiangfeng

2012-09-01

One of the computational challenges in plant systems biology is to accurately infer transcriptional regulation relationships based on correlation analyses of gene expression patterns. Despite several correlation methods that are applied in biology to analyze microarray data, concerns regarding the compatibility of these methods with the gene expression data profiled by high-throughput RNA transcriptome sequencing (RNA-Seq) technology have been raised. These concerns are mainly due to the fact that the distribution of read counts in RNA-Seq experiments is different from that of fluorescence intensities in microarray experiments. Therefore, a comprehensive evaluation of the existing correlation methods and, if necessary, introduction of novel methods into biology is appropriate. In this study, we compared four existing correlation methods used in microarray analysis and one novel method called the Gini correlation coefficient on previously published microarray-based and sequencing-based gene expression data in Arabidopsis (Arabidopsis thaliana) and maize (Zea mays). The comparisons were performed on more than 11,000 regulatory relationships in Arabidopsis, including 8,929 pairs of transcription factors and target genes. Our analyses pinpointed the strengths and weaknesses of each method and indicated that the Gini correlation can compensate for the shortcomings of the Pearson correlation, the Spearman correlation, the Kendall correlation, and the Tukey's biweight correlation. The Gini correlation method, with the other four evaluated methods in this study, was implemented as an R package named rsgcc that can be utilized as an alternative option for biologists to perform clustering analyses of gene expression patterns or transcriptional network analyses.
Reliability and Validity of Wisconsin Upper Respiratory Symptom Survey, Korean Version

PubMed Central

Yang, Su-Young; Kang, Weechang; Yeo, Yoon; Park, Yang-Chun

2011-01-01

Background The Wisconsin Upper Respiratory Symptom Survey (WURSS) is a self-administered questionnaire developed in the United States to evaluate the severity of the common cold and its reliability has been validated. We developed a Korean language version of this questionnaire by using a sequential forward and backward translation approach. The purpose of this study was to validate the Korean version of the Wisconsin Upper Respiratory Symptom Survey (WURSS-K) in Korean patients with common cold. Methods This multicenter prospective study enrolled 107 participants who were diagnosed with common cold and consented to participate in the study. The WURSS-K includes 1 global illness severity item, 32 symptom-based items, 10 functional quality-of-life (QOL) items, and 1 item assessing global change. The SF-8 was used as an external comparator. Results The participants were 54 women and 53 men aged 18 to 42 years. The WURSS-K showed good reliability in 10 domains, with Cronbach’s alphas ranging from 0.67 to 0.96 (mean: 0.84). Comparison of the reliability coefficients of the WURSS-K and WURSS yielded a Pearson correlation coefficient of 0.71 (P = 0.02). Validity of the WURSS-K was evaluated by comparing it with the SF-8, which yielded a Pearson correlation coefficient of −0.267 (P < 0.001). The Guyatt’s responsiveness index of the WURSS-K ranged from 0.13 to 0.46, and the correlation coefficient with the WURSS was 0.534 (P < 0.001), indicating that there was close correlation between the WURSS-K and WURSS. Conclusions The WURSS-K is a reliable, valid, and responsive disease-specific questionnaire for assessing symptoms and QOL in Korean patients with common cold. PMID:21691034
Validation of the Personal Need for Structure Scale in Chinese.

PubMed

Shi, Junqi; Wang, Lei; Chen, Yang

2009-08-01

To validate the Chinese version of the Personal Need for Structure Scale, questionnaires were administered to 1,418 individuals in three samples. Item-total correlations and internal consistency of the scale were acceptable. The test-retest reliability was .79. Confirmatory factor analysis indicated that the Chinese version comprised two dimensions, as did the original version; Desire for Structure and Response to Lack of Structure. Correlation coefficients between the Personal Need for Structure Scale and other related measures indicated that the scale has acceptable discriminant validity and convergent validity.
The reliability and validity of a Japanese version of symptom checklist 90 revised

PubMed Central

Tomioka, Mitsunao; Shimura, Midori; Hidaka, Mikio; Kubo, Chiharu

2008-01-01

Objective To examine the validity and reliability of a Japanese version of the Symptom Checklist 90 Revised (SCL-90-R (J)). Methods The English SCL-90-R was translated to Japanese and the Japanese version confirmed by back-translation. To determine the factor validity and internal consistency of the nine primary subscales, 460 people from the community completed SCL-90-R(J). Test-retest reliability was examined for 104 outpatients and 124 healthy undergraduate students. The convergent-discriminant validity was determined for 80 inpatients who replied to both SCL-90-R(J) and the Minnesota Multiphasic Personality Inventory (MMPI). Results The correlation coefficients between the nine primary subscales and items were .26 to .78. Cronbach's alpha coefficients were from .76 (Phobic Anxiety) to .86 (Interpersonal Sensitivity). Pearson's correlation coefficients between test-retest scores were from .81 (Psychoticism) to .90 (Somatization) for the outpatients and were from .64 (Phobic Anxiety) to .78 (Paranoid Ideation) for the students. Each of the nine primary subscales correlated well with their corresponding constructs in the MMPI. Conclusion We confirmed the validity and reliability of SCL-90-R(J) for the measurement of individual distress. The nine primary subscales were consistent with the items of the original English version. PMID:18957078
Fast-GPU-PCC: A GPU-Based Technique to Compute Pairwise Pearson's Correlation Coefficients for Time Series Data-fMRI Study.

PubMed

Eslami, Taban; Saeed, Fahad

2018-04-20

Functional magnetic resonance imaging (fMRI) is a non-invasive brain imaging technique, which has been regularly used for studying brain’s functional activities in the past few years. A very well-used measure for capturing functional associations in brain is Pearson’s correlation coefficient. Pearson’s correlation is widely used for constructing functional network and studying dynamic functional connectivity of the brain. These are useful measures for understanding the effects of brain disorders on connectivities among brain regions. The fMRI scanners produce huge number of voxels and using traditional central processing unit (CPU)-based techniques for computing pairwise correlations is very time consuming especially when large number of subjects are being studied. In this paper, we propose a graphics processing unit (GPU)-based algorithm called Fast-GPU-PCC for computing pairwise Pearson’s correlation coefficient. Based on the symmetric property of Pearson’s correlation, this approach returns N ( N − 1 ) / 2 correlation coefficients located at strictly upper triangle part of the correlation matrix. Storing correlations in a one-dimensional array with the order as proposed in this paper is useful for further usage. Our experiments on real and synthetic fMRI data for different number of voxels and varying length of time series show that the proposed approach outperformed state of the art GPU-based techniques as well as the sequential CPU-based versions. We show that Fast-GPU-PCC runs 62 times faster than CPU-based version and about 2 to 3 times faster than two other state of the art GPU-based methods.
Correlation dependence of the volumetric thermal expansion coefficient of metallic aluminum on its heat capacity

NASA Astrophysics Data System (ADS)

Bodryakov, V. Yu.; Bykov, A. A.

2016-05-01

The correlation between the volumetric thermal expansion coefficient β( T) and the heat capacity C( T) of aluminum is considered in detail. It is shown that a clear correlation is observed in a significantly wider temperature range, up to the melting temperature of the metal, along with the low-temperature range where it is linear. The significant deviation of dependence β( C) from the low-temperature linear behavior is observed up to the point where the heat capacity achieves the classical Dulong-Petit limit of 3 R ( R is the universal gas constant).
Correlation and path coefficient analysis of quantitative characters in spine gourd (Momordica dioica Roxb.).

PubMed

Aliya, F; Begum, H; Reddy, M T; Sivaraj, N; Pandravada, S R; Narshimulu, G

2014-05-01

Fifty genotypes of spine gourd (Momordica dioica Roxb.) were evaluated in a randomized block design with two replications at the Vegetable Research Station, Rajendranagar, Hyderabad, Andhra Pradesh, India during kharif, 2012. Correlation and path coefficient analysis were carried out to study the character association and contribution, respectively for twelve quantitative characters namely vine length (m), number of stems per plant, days to first female flower appearance, first female flowering node, days to first fruit harvest, days to last fruit harvest, fruiting period (days), fruit length (cm), fruit width (cm), fruit weight (g), number of fruits per plant and fruit yield per plant (kg) for identification of the potential selection indices. Correlation and path coefficient analyses revealed that fruiting period and number of fruits per plant not only had positively significant correlation with fruit yield but also had positively high direct effect on it and are regarded as the main determinants of fruit yield. Days to first fruit harvest had positively moderate direct effect on fruit yield and its association was negatively significant, days to last fruit harvest had negatively high direct effect on fruit yield and its association was significant positively, hence restricted simultaneous selection can be made for days to first fruit harvest and days to last fruit harvest. The improvement in fruit yield can be effective if selection is based on days to first fruit harvest, days to last fruit harvest, fruiting period and number of fruits per plant.
A Method of Q-Matrix Validation for the Linear Logistic Test Model

PubMed Central

Baghaei, Purya; Hohensinn, Christine

2017-01-01

The linear logistic test model (LLTM) is a well-recognized psychometric model for examining the components of difficulty in cognitive tests and validating construct theories. The plausibility of the construct model, summarized in a matrix of weights, known as the Q-matrix or weight matrix, is tested by (1) comparing the fit of LLTM with the fit of the Rasch model (RM) using the likelihood ratio (LR) test and (2) by examining the correlation between the Rasch model item parameters and LLTM reconstructed item parameters. The problem with the LR test is that it is almost always significant and, consequently, LLTM is rejected. The drawback of examining the correlation coefficient is that there is no cut-off value or lower bound for the magnitude of the correlation coefficient. In this article we suggest a simulation method to set a minimum benchmark for the correlation between item parameters from the Rasch model and those reconstructed by the LLTM. If the cognitive model is valid then the correlation coefficient between the RM-based item parameters and the LLTM-reconstructed item parameters derived from the theoretical weight matrix should be greater than those derived from the simulated matrices. PMID:28611721
Spaced antenna diversity in temperate latitude meteor burst systems operating near 40 MHz - Variation of signal cross-correlation coefficients with antenna separation

NASA Astrophysics Data System (ADS)

Cannon, Paul S.; Shukla, Anil K.; Lester, Mark

1993-04-01

We have studied 37-MHz signals received over an 800-km temperate latitude path using 400-W continuous wave transmissions. Signals collected during a 9-day period in February 1990 on two antennas at separations of 5, 10, and 20 lambda were analyzed. Three signal categories were identified (overdense, underdense, and not known (NK)) and cross-correlation coefficients between the signals received by the two antennas were calculated for each signal category. No spatial variation, and in particular no decrease, in average cross-correlation coefficient was observed for underdense or NK signals as the antenna spacing was increased from 5 to 20 lambda. At each antenna separation the cross-correlation coefficients of these two categories were strongly dependent on time. Overdense signals, however, showed no cross-correlation time dependency at 5 and 10 lambda, but there was a strong time dependency at 20 lambda. Recommendations are made in regard to the optimum antenna spacing for a meteor burst communication system using spaced antenna diversity.
An asymptotic theory for cross-correlation between auto-correlated sequences and its application on neuroimaging data.

PubMed

Zhou, Yunyi; Tao, Chenyang; Lu, Wenlian; Feng, Jianfeng

2018-04-20

Functional connectivity is among the most important tools to study brain. The correlation coefficient, between time series of different brain areas, is the most popular method to quantify functional connectivity. Correlation coefficient in practical use assumes the data to be temporally independent. However, the time series data of brain can manifest significant temporal auto-correlation. A widely applicable method is proposed for correcting temporal auto-correlation. We considered two types of time series models: (1) auto-regressive-moving-average model, (2) nonlinear dynamical system model with noisy fluctuations, and derived their respective asymptotic distributions of correlation coefficient. These two types of models are most commonly used in neuroscience studies. We show the respective asymptotic distributions share a unified expression. We have verified the validity of our method, and shown our method exhibited sufficient statistical power for detecting true correlation on numerical experiments. Employing our method on real dataset yields more robust functional network and higher classification accuracy than conventional methods. Our method robustly controls the type I error while maintaining sufficient statistical power for detecting true correlation in numerical experiments, where existing methods measuring association (linear and nonlinear) fail. In this work, we proposed a widely applicable approach for correcting the effect of temporal auto-correlation on functional connectivity. Empirical results favor the use of our method in functional network analysis. Copyright © 2018. Published by Elsevier B.V.
Intra- and inter-tester reliability and validity of normal finger size measurement using the Japanese ring gauge system.

PubMed

Suzuki, T; Sato, Y; Sotome, S; Arai, H; Arai, A; Yoshida, H

2017-06-01

This study was designed to investigate the reliability and validity of measurements of finger diameters with a ring gauge. A reliability study enrolled two independent samples (50 participants and seven examiners in Study I; 26 participants and 26 examiners in Study II). The sizes of each participant's little fingers were measured twice with a ring gauge by each examiner. To investigate the validity of the measurements, five hand therapists compared the finger size and hand volume of 30 participants with the ring gauge and with a figure-of-eight technique (Study III). The intra-class correlation coefficient for intra-observer reliability ranged from 0.97 to 0.99 in Study I, and 0.90 to 0.97 in Study II. The intra-class correlation coefficient for inter-observer reliability was 0.95 in Study I and 0.94 in Study II. The validity study showed a Pearson product moment correlation coefficient of 0.75. The ring gauge showed high reliability and validity for measurement of finger size. III, diagnostic.
Reliability and validity of a quantitative color scale to evaluate masticatory performance using color-changeable chewing gum.

PubMed

Hama, Yohei; Kanazawa, Manabu; Minakuchi, Shunsuke; Uchida, Tatsuro; Sasaki, Yoshiyuki

2014-03-19

In the present study, we developed a novel color scale for visual assessment, conforming to theoretical color changes of a gum, to evaluate masticatoryperformance; moreover, we investigated the reliability and validity of this evaluation method using the color scale. Ten participants (aged 26.30 years) with natural dentition chewed the gum at several chewing strokes. Changes in color were measured using a colorimeter, and then, linearregression expressions that represented changes in gum color were derived. The color scale was developed using these regression expressions. Thirty-two chewed gums were evaluated using colorimeter and were assessed three times using the color scale by six dentists aged 25.27 (mean, 25.8) years, six preclinical dental students aged 21.23 (mean, 22.2) years, and six elderly individuals aged 68.84 (mean, 74.0) years. The intrarater and interrater reliability of evaluations was assessed using intraclass correlation coefficients. Validity of the method compared with a colorimeter was assessed using Spearman's rank correlation coefficient. All intraclass correlation coefficients were > 0.90, and Spearman's rank-correlation coefficients were > 0.95 in all groups. These results indicated that the evaluation method of the color-changeable chewing gum using the newly developed color scale is reliable and valid.
[Reliability and validity of the modified Perceived Health Competence Scale (PHCS) Japanese version].

PubMed

Togari, Taisuke; Yamazaki, Yoshihiko; Koide, Syotaro; Miyata, Ayako

2006-01-01

In community and workplace health plans, the Perceived Health Competence Scale (PHCS) is employed as an index of health competency. The purpose of this research was to examine the reliability and validity of a modified Japanese PHCS. Interviews were sought with 3,000 randomly selected Japanese individuals using a two-step stratified method. Valid PHCS responses were obtained from 1,910 individuals, yielding a 63.7% response rate. Reliability was assessed using Cronbach's alpha coefficient (henceforth, alpha) to evaluate internal consistency, and by employing item-total correlation and alpha coefficient analyses to assess the effect of removal of variables from the model. To examine content validity, we assessed the correlation between the PHCS score and four respondent attribute characteristics, that is, sex, age, the presence of chronic disease, and the existence of chronic disease at age 18. The correlation between PHCS score and commonly employed healthy lifestyle indices was examined to assess construct validity. General linear model statistical analysis was employed. The modified Japanese PHCS demonstrated a satisfactory alpha coefficient of 0.869. Moreover, reliability was confirmed by item-total correlation and alpha coefficient analyses after removal of variables from the model. Differences in PHCS scores were seen between individuals 60 years and older, and younger individuals. These with current chronic disease, or who had had a chronic disease at age 18, tended to have lower PHCS scores. After controlling for the presence of current or age 18 chronic disease, age, and sex, significant correlations were seen between PHCS scores and tobacco use, dietary habits, and exercise, but not alcohol use or frequency of medical consultation. This study supports the reliability and validity, and hence supports the use, of the modified Japanese PHCS. Future longitudinal research is needed to evaluate the predictive power of modified Japanese PHCS scores, to examine
Needs of caregivers of cancer patients: validation of the Mexican version of the Support Person Unmet Needs Survey (SPUNS-SFM).

PubMed

Doubova, Svetlana V; Aguirre-Hernandez, Rebeca; Infante-Castañeda, Claudia; Martinez-Vega, Ingrid; Pérez-Cuevas, Ricardo

2015-10-01

The purpose of this study was to validate the Mexican version of the Support Person Unmet Needs Survey (SPUNS-SFM). A cross-sectional survey that included 826 primary caregivers of cancer patients was conducted from June to December 2013 at the Oncology Hospital of the Mexican Institute of Social Security in Mexico City. The validation procedure comprised (1) content validity through a group of experts; (2) construct validity through an exploratory factor analysis based on the polychoric correlation matrix; (3) internal consistency using Cronbach's alpha; (4) convergent validity between SPUNS-SFM and quality of life, anxiety-and-depression scales by calculating Spearman's rank correlation coefficient;( 5) discriminative validity through the Wilcoxon rank-sum test; and (6) test-retest reliability using intraclass correlation coefficient. SPUNS-SFM has 23 items with six factors accounting for 65 % of the total variance. The domains were concerns about the future, access and continuity of healthcare, information, work and finance, and personal and emotional needs. Cronbach's alpha values ranged from 0.70 to 0.88 among factors. SPUNS-SFM had moderate convergent validity compared with quality of life and depression-and-anxiety scales and good discriminative validity, revealing high needs for younger caregivers and more emotional needs for caregivers of patients with advanced cancer stages. Intraclass correlation coefficient between SPUNS-SFM measurements was 0.78. SPUNS-SFM is a valid and reliable tool to identify needs of caregivers of cancer patients.
Development and Psychometric Validation of HIPER-Q to Assess Knowledge of Hypertensive Patients in Cardiac Rehabilitation.

PubMed

Santos, Rafaella Zulianello Dos; Bonin, Christiani Decker Batista; Martins, Eliara Ten Caten; Pereira Junior, Moacir; Ghisi, Gabriela Lima de Melo; Macedo, Kassia Rosangela Paz de; Benetti, Magnus

2018-01-01

The absence of instruments capable of measuring the level of knowledge of hypertensive patients in cardiac rehabilitation programs about their disease reflects the lack of specific recommendations for these patients. To develop and validate a questionnaire to evaluate the knowledge of hypertensive patients in cardiac rehabilitation programs about their disease. A total of 184 hypertensive patients (mean age 60.5 ± 10 years, 66.8% men) were evaluated. Reproducibility was assessed by calculation of the intraclass correlation coefficient using the test-retest method. Internal consistency was assessed by the Cronbach's alpha and the construct validity by the exploratory factorial analysis. The final version of the instrument had 17 questions organized in areas considered important for patient education. The instrument proposed showed a clarity index of 8.7 (0.25). The intraclass correlation coefficient was 0.804 and the Cronbach's correlation coefficient was 0.648. Factor analysis revealed five factors associated with knowledge areas. Regarding the criterion validity, patients with higher education level and higher family income showed greater knowledge about hypertension. The instrument has a satisfactory clarity index and adequate validity, and can be used to evaluate the knowledge of hypertensive participants in cardiac rehabilitation programs.
Concurrent validity and reliability of the Alberta Infant Motor Scale in premature infants.

PubMed

Almeida, Kênnea Martins; Dutra, Maria Virginia Peixoto; Mello, Rosane Reis de; Reis, Ana Beatriz Rodrigues; Martins, Priscila Silveira

2008-01-01

To verify the concurrent validity and interobserver reliability of the Alberta Infant Motor Scale (AIMS) in premature infants followed-up at the outpatient clinic of Instituto Fernandes Figueira, Fundação Oswaldo Cruz (IFF/Fiocruz), in Rio de Janeiro, Brazil. A total of 88 premature infants were enrolled at the follow-up clinic at IFF/Fiocruz, between February and December of 2006. For the concurrent validity study, 46 infants were assessed at either 6 (n = 26) or 12 (n = 20) months' corrected age using the AIMS and the second edition of the Bayley Scales of Infant Development, by two different observers, and applying Pearson's correlation coefficient to analyze the results. For the reliability study, 42 infants between 0 and 18 months were assessed using the Alberta Infant Motor Scale, by two different observers and the results analyzed using the intraclass correlation coefficient. The concurrent validity study found a high level of correlation between the two scales (r = 0.95) and one that was statistically significant (p < 0.01) for the entire population of infants, with higher values at 12 months (r = 0.89) than at 6 months (r = 0.74). The interobserver reliability study found satisfactory intraclass correlation coefficients at all ages tested, varying from 0.76 to 0.99. The AIMS is a valid and reliable instrument for the evaluation of motor development in high-risk infants within the Brazilian public health system.
Measuring the diffusion coefficient of ganglioside on cell membrane by fluorescence correlation spectroscopy

NASA Astrophysics Data System (ADS)

Dong, Shiqing; You, Minghai; Chen, Jianling; Zhou, Jie; Xie, Shusen; Yang, Hongqin

2017-06-01

The fluidity of proteins and lipids on cell membrane plays an important role in cell’s physiological functions. Fluorescence correlation spectroscopy (FCS) is an effective technique to detect the rapid dynamic behaviors of proteins and/or lipids in living cells. In this study, we used the rhodamine6G solution to optimize the FCS system. And, cholera toxin B subunit (CT-B) was used to label ganglioside on living Hela cell membranes. The diffusion time and coefficients of ganglioside can be obtained through fitting the autocorrelation curve based on the model of two-dimensional cell membrane. The results showed that the diffusion coefficients of ganglioside distributed within a wide range. It revealed the lateral diffusion of lipids on cell membrane was inhomogeneous, which was due to different microstructures of cytoplasmic membrane. The study provides a helpful method for further studying the dynamic characteristics of proteins and lipids molecules on living cell membrane.
Development and validation of the Myasthenia Gravis Impairment Index.

PubMed

Barnett, Carolina; Bril, Vera; Kapral, Moira; Kulkarni, Abhaya; Davis, Aileen M

2016-08-30

We aimed to develop a measure of myasthenia gravis impairment using a previously developed framework and to evaluate reliability and validity, specifically face, content, and construct validity. The first draft of the Myasthenia Gravis Impairment Index (MGII) included examination items from available measures enriched with newly developed, patient-reported items, modified after patient input. International neuromuscular specialists evaluated face and content validity via an e-mail survey. Test-retest reliability was assessed in stable patients at a 3-week interval and interrater reliability was evaluated in the same day. Construct validity was assessed through correlations between the MGII and other measures and by comparing scores in different patient groups. The first draft was assessed by 18 patients, and 72 specialists answered the survey. The second draft had 7 examination and 22 patient-reported items. Field testing included 200 patients, with 54 patients completing the reliability studies. Test-retest reliability of the total score was good (intraclass correlation coefficient 0.92; 95% confidence interval 0.79-0.94), as was interrater reliability of the examination component (intraclass correlation coefficient 0.81; 95% confidence interval 0.79-0.94). The MGII correlated well with comparison measures, with higher correlations with the MG-activities of daily living (r = 0.91) and MG-specific quality of life 15-item scale (r = 0.78). When assessing different patient groups, the scores followed expected patterns. The MGII was developed using a patient-centered framework of myasthenia-related impairments and incorporating patient input throughout the development process. It is reliable in an outpatient setting and has demonstrated construct validity. Responsiveness studies are under way. © 2016 American Academy of Neurology.

Development and validation of the Myasthenia Gravis Impairment Index

PubMed Central

Bril, Vera; Kapral, Moira; Kulkarni, Abhaya; Davis, Aileen M.

2016-01-01

Objective: We aimed to develop a measure of myasthenia gravis impairment using a previously developed framework and to evaluate reliability and validity, specifically face, content, and construct validity. Methods: The first draft of the Myasthenia Gravis Impairment Index (MGII) included examination items from available measures enriched with newly developed, patient-reported items, modified after patient input. International neuromuscular specialists evaluated face and content validity via an e-mail survey. Test–retest reliability was assessed in stable patients at a 3-week interval and interrater reliability was evaluated in the same day. Construct validity was assessed through correlations between the MGII and other measures and by comparing scores in different patient groups. Results: The first draft was assessed by 18 patients, and 72 specialists answered the survey. The second draft had 7 examination and 22 patient-reported items. Field testing included 200 patients, with 54 patients completing the reliability studies. Test–retest reliability of the total score was good (intraclass correlation coefficient 0.92; 95% confidence interval 0.79–0.94), as was interrater reliability of the examination component (intraclass correlation coefficient 0.81; 95% confidence interval 0.79–0.94). The MGII correlated well with comparison measures, with higher correlations with the MG–activities of daily living (r = 0.91) and MG-specific quality of life 15-item scale (r = 0.78). When assessing different patient groups, the scores followed expected patterns. Conclusions: The MGII was developed using a patient-centered framework of myasthenia-related impairments and incorporating patient input throughout the development process. It is reliable in an outpatient setting and has demonstrated construct validity. Responsiveness studies are under way. PMID:27402891
Negative Coefficients in the GRE Validity Study Service. GRE Research. GRE Board Professional Report No. 89-05P.

ERIC Educational Resources Information Center

Longford, Nicholas T.

Operational procedures for the Graduate Record Examinations Validity Study Service are reviewed, with emphasis on the problem of frequent occurrence of negative coefficients in the fitted within-department regressions obtained by the empirical Bayes method of H. I. Braun and D. Jones (1985). Several alterations of the operational procedures are…
Validity and reliability of a new ankle dorsiflexion measurement device.

PubMed

Gatt, Alfred; Chockalingam, Nachiappan

2013-08-01

The assessment of the maximum ankle dorsiflexion angle is an important clinical examination procedure. Evidence shows that the traditional goniometer is highly unreliable, and various designs of goniometers to measure the maximum ankle dorsiflexion angle rely on the application of a known force to obtain reliable results. Hence, an innovative ankle dorsiflexion measurement device was designed to make this measurement more reliable by holding the foot in a selected posture without the application of a known moment. To report on the comprehensive validity and reliability testing carried out on the new device. Following validity testing, four different trials to test reliability of the ankle dorsiflexion measurement device were performed. These trials included inter-rater and intra-rater testings with a controlled moment, intra-rater reliability testing with knees flexed and extended without a controlled moment, intra-rater testing with a patient population, and inter-rater reliability testing between four raters of varying experience without controlling moment. All raters were blinded. A series of trials to test intra-rater and inter-rater reliabilities. Intra-rater reliability intraclass correlation coefficient was 0.98 and inter-rater reliability intraclass correlation coefficient (2,1) was 0.953 with a controlled moment. With uncontrolled moment, very high reliability for intra-tester was also achieved (intraclass correlation coefficient = 0.94 with knees extended and intraclass correlation coefficient = 0.95 with knees flexed). For the trial investigating test-retest reliability with actual patients, intraclass correlation coefficient of 0.99 was obtained. In the trial investigating four different raters with uncontrolled moment, intraclass correlation coefficient of 0.91 was achieved. The new ankle dorsiflexion measurement device is a valid and reliable device for measuring ankle dorsiflexion in both healthy subjects and patients, with both controlled and
The Impact of Overreporting on MMPI-2-RF Substantive Scale Score Validity

ERIC Educational Resources Information Center

Burchett, Danielle L.; Ben-Porath, Yossef S.

2010-01-01

This study examined the impact of overreporting on the validity of Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) substantive scale scores by comparing correlations with relevant external criteria (i.e., validity coefficients) of individuals who completed the instrument under instructions to (a) feign psychopathology…
Translation, Cultural Adaptation and Validation of the Simple Shoulder Test to Spanish

PubMed Central

Arcuri, Francisco; Barclay, Fernando; Nacul, Ivan

2015-01-01

Background: The validation of widely used scales facilitates the comparison across international patient samples. Objective: The objective was to translate, culturally adapt and validate the Simple Shoulder Test into Argentinian Spanish. Methods: The Simple Shoulder Test was translated from English into Argentinian Spanish by two independent translators, translated back into English and evaluated for accuracy by an expert committee to correct the possible discrepancies. It was then administered to 50 patients with different shoulder conditions.Psycometric properties were analyzed including internal consistency, measured with Cronbach´s Alpha, test-retest reliability at 15 days with the interclass correlation coefficient. Results: The internal consistency, validation, was an Alpha of 0,808, evaluated as good. The test-retest reliability index as measured by intra-class correlation coefficient (ICC) was 0.835, evaluated as excellent. Conclusion: The Simple Shoulder Test translation and it´s cultural adaptation to Argentinian-Spanish demonstrated adequate internal reliability and validity, ultimately allowing for its use in the comparison with international patient samples.
Estimation of influential points in any data set from coefficient of determination and its leave-one-out cross-validated counterpart.

PubMed

Tóth, Gergely; Bodai, Zsolt; Héberger, Károly

2013-10-01

Coefficient of determination (R (2)) and its leave-one-out cross-validated analogue (denoted by Q (2) or R cv (2) ) are the most frequantly published values to characterize the predictive performance of models. In this article we use R (2) and Q (2) in a reversed aspect to determine uncommon points, i.e. influential points in any data sets. The term (1 - Q (2))/(1 - R (2)) corresponds to the ratio of predictive residual sum of squares and the residual sum of squares. The ratio correlates to the number of influential points in experimental and random data sets. We propose an (approximate) F test on (1 - Q (2))/(1 - R (2)) term to quickly pre-estimate the presence of influential points in training sets of models. The test is founded upon the routinely calculated Q (2) and R (2) values and warns the model builders to verify the training set, to perform influence analysis or even to change to robust modeling.
Several submaximal exercise tests are reliable, valid and acceptable in people with chronic pain, fibromyalgia or chronic fatigue: a systematic review.

PubMed

Ratter, Julia; Radlinger, Lorenz; Lucas, Cees

2014-09-01

Are submaximal and maximal exercise tests reliable, valid and acceptable in people with chronic pain, fibromyalgia and fatigue disorders? Systematic review of studies of the psychometric properties of exercise tests. People older than 18 years with chronic pain, fibromyalgia and chronic fatigue disorders. Studies of the measurement properties of tests of physical capacity in people with chronic pain, fibromyalgia or chronic fatigue disorders were included. Studies were required to report: reliability coefficients (intraclass correlation coefficient, alpha reliability coefficient, limits of agreements and Bland-Altman plots); validity coefficients (intraclass correlation coefficient, Spearman's correlation, Kendal T coefficient, Pearson's correlation); or dropout rates. Fourteen studies were eligible: none had low risk of bias, 10 had unclear risk of bias and four had high risk of bias. The included studies evaluated: Åstrand test; modified Åstrand test; Lean body mass-based Åstrand test; submaximal bicycle ergometer test following another protocol other than Åstrand test; 2-km walk test; 5-minute, 6-minute and 10-minute walk tests; shuttle walk test; and modified symptom-limited Bruce treadmill test. None of the studies assessed maximal exercise tests. Where they had been tested, reliability and validity were generally high. Dropout rates were generally acceptable. The 2-km walk test was not recommended in fibromyalgia. Moderate evidence was found for reliability, validity and acceptability of submaximal exercise tests in patients with chronic pain, fibromyalgia or chronic fatigue. There is no evidence about maximal exercise tests in patients with chronic pain, fibromyalgia and chronic fatigue. Copyright © 2014. Published by Elsevier B.V.
The Outpatient Experience Questionnaire of comprehensive public hospital in China: development, validity and reliability.

PubMed

Hu, Yinhuan; Zhang, Zixia; Xie, Jinzhu; Wang, Guanping

2017-02-01

The objective of this study is to describe the development of the Outpatient Experience Questionnaire (OPEQ) and to assess the validity and reliability of the scale. Literature review, patient interviews, Delphi method and Cross-sectional validation survey. Six comprehensive public hospitals in China. The survey was carried out on a sample of 600 outpatients. Acceptability of the questionnaire was assessed according to the overall response rate, item non-response rate and the average completion time. Correlation coefficients and confirmatory factor analysis were used to test construct validity. Delphi method was used to assess the content validity of the questionnaire. Cronbach's coefficient alpha and split-half reliability coefficient were used to estimate the internal reliability of the questionnaire. The overall response rate was 97.2% and the item non-response rate ranged from 0% to 0.3%. The mean completion time was 6 min. The Spearman correlations of item-total score ranged from 0.466 to 0.765. The results of confirmatory factor analysis showed that all items had factor loadings above 0.40 and the dimension intercorrelation ranged from 0.449 to 0.773, the goodness of fit of the questionnaire was reasonable. The overall authority grade of expert consultation was 0.80 and Kendall's coefficient of concordance W was 0.186. The Cronbach's coefficients alpha of six dimensions ranged from 0.708 to 0.895, the split-half reliability coefficient (Spearman-Brown coefficient) was 0.969. The OPEQ is a promising instrument covering the most important aspects which influence outpatient experiences of comprehensive public hospital in China. It has good evidence for acceptability, validity and reliability. © The Author 2016. Published by Oxford University Press in association with the International Society for Quality in Health Care. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
Development and validation of a fatigue assessment scale for U.S. construction workers.

PubMed

Zhang, Mingzong; Sparer, Emily H; Murphy, Lauren A; Dennerlein, Jack T; Fang, Dongping; Katz, Jeffrey N; Caban-Martinez, Alberto J

2015-02-01

To develop a fatigue assessment scale and test its reliability and validity for commercial construction workers. Using a two-phased approach, we first identified items (first phase) for the development of a Fatigue Assessment Scale for Construction Workers (FASCW) through review of existing scales in the scientific literature, key informant interviews (n = 11) and focus groups (three groups with six workers each) with construction workers. The second phase included assessment for the reliability, validity, and sensitivity of the new scale using a repeated-measures study design with a convenience sample of construction workers (n = 144). Phase one resulted in a 16-item preliminary scale that after factor analysis yielded a final 10-item scale with two sub-scales ("Lethargy" and "Bodily Ailment"). During phase two, the FASCW and its subscales demonstrated satisfactory internal consistency (alpha coefficients were FASCW [0.91], Lethargy [0.86] and Bodily Ailment [0.84]) and acceptable test-retest reliability (Pearson Correlations Coefficients: 0.59-0.68; Intraclass Correlation Coefficients: 0.74-0.80). Correlation analysis substantiated concurrent and convergent validity. A discriminant analysis demonstrated that the FASCW differentiated between groups with arthritis status and different work hours. The 10-item FASCW with good reliability and validity is an effective tool for assessing the severity of fatigue among construction workers. © 2015 Wiley Periodicals, Inc.
Development and Validation of a Fatigue Assessment Scale for U.S. Construction Workers

PubMed Central

Zhang, Mingzong; Sparer, Emily H.; Murphy, Lauren A.; Dennerlein, Jack T.; Fang, Dongping; Katz, Jeffrey N.; Caban-Martinez, Alberto J.

2015-01-01

Objective To develop a fatigue assessment scale and test its reliability and validity for commercial construction workers. Methods Using a two-phased approach, we first identified items for the development of a Fatigue Assessment Scale for Construction Workers (FASCW) through review of existing scales in the scientific literature, key informant interviews (n=11) and focus groups (3 groups with 6 workers each) with construction workers. The second phase included assessment for the reliability, validity and sensitivity of the new scale using a repeated-measures study design with a convenience sample of construction workers (n=144). Results Phase one resulted in a 16-item preliminary scale that after factor analysis yielded a final 10-item scale with two sub-scales (“Lethargy” and “Bodily Ailment”).. During phase two, the FASCW and its subscales demonstrated satisfactory internal consistency (alpha coefficients were FASCW (0.91), Lethargy (0.86) and Bodily Ailment (0.84)) and acceptable test-retest reliability (Pearson Correlations Coefficients: 0.59–0.68; Intraclass Correlation Coefficients: 0.74–0.80). Correlation analysis substantiated concurrent and convergent validity. A discriminant analysis demonstrated that the FASCW differentiated between groups with arthritis status and different work hours. Conclusions The 10-item FASCW with good reliability and validity is an effective tool for assessing the severity of fatigue among construction workers. PMID:25603944
Validation of a New Metric for Assessing the Integration of Health Protection and Health Promotion in a Sample of Small- and Medium-Sized Employer Groups.

PubMed

Williams, Jessica A R; Nelson, Candace C; Cabán-Martinez, Alberto J; Katz, Jeffrey N; Wagner, Gregory R; Pronk, Nicolaas P; Sorensen, Glorian; McLellan, Deborah L

2015-09-01

To conduct validation analyses for a new measure of the integration of worksite health protection and health promotion approaches developed in earlier research. A survey of small- to medium-sized employers located in the United States was conducted between October 2013 and March 2014 (n = 111). Cronbach α coefficient was used to assess reliability, and Pearson correlation coefficients were used to assess convergent validity. The integration score was positively associated with the measures of occupational safety and health and health promotion activities/policies-supporting its convergent validity (Pearson correlation coefficients of 0.32 to 0.47). Cronbach α coefficient was 0.94, indicating excellent reliability. The integration score seems to be a promising tool for assessing integration of health promotion and health protection. Further work is needed to test its dimensionality and validate its use in other samples.
Prediction of stream volatilization coefficients

USGS Publications Warehouse

Rathbun, Ronald E.

1990-01-01

Equations are developed for predicting the liquid-film and gas-film reference-substance parameters for quantifying volatilization of organic solutes from streams. Molecular weight and molecular-diffusion coefficients of the solute are used as correlating parameters. Equations for predicting molecular-diffusion coefficients of organic solutes in water and air are developed, with molecular weight and molal volume as parameters. Mean absolute errors of prediction for diffusion coefficients in water are 9.97% for the molecular-weight equation, 6.45% for the molal-volume equation. The mean absolute error for the diffusion coefficient in air is 5.79% for the molal-volume equation. Molecular weight is not a satisfactory correlating parameter for diffusion in air because two equations are necessary to describe the values in the data set. The best predictive equation for the liquid-film reference-substance parameter has a mean absolute error of 5.74%, with molal volume as the correlating parameter. The best equation for the gas-film parameter has a mean absolute error of 7.80%, with molecular weight as the correlating parameter.
Validation of the MISSCARE-BRASIL survey - A tool to assess missed nursing care.

PubMed

Siqueira, Lillian Dias Castilho; Caliri, Maria Helena Larcher; Haas, Vanderlei José; Kalisch, Beatrice; Dantas, Rosana Aparecida Spadoti

2017-12-21

to analyze the metric validity and reliability properties of the MISSCARE-BRASIL survey. methodological research conducted by assessing construct validity and reliability via confirmatory factor analysis, known-groups validation, convergent construct validation, analysis of internal consistency and test-retest reliability. The sample consisted of 330 nursing professionals, of whom 86 participated in the retest phase. of the 330 participants, 39.7% were aides, 33% technicians, 20.9% nurses, and 6.4% nurses with administrative roles. Confirmatory factorial analysis demonstrated that the Brazilian Portuguese version of the instrument is adequately adjusted to the dimensional structure the scale authors originally proposed. The correlation between "satisfaction with position/role" and "satisfaction with teamwork" and the survey's missed care variables was moderate (Spearman's coefficient =0.35; p<0.001). The results of the Student's t-test indicated known-group validity. Professionals from closed units reported lower levels of missed care in comparison with the other units. The reliability showed a strong correlation, with the exception of "institutional management/leadership style" (intraclass correlation coefficient (ICC)=0.15; p=0.04). The internal consistency was adequate (Cronbach's alpha was greater than 0.70). the MISSCARE-BRASIL was valid and reliable in the group studied. The application of the MISSCARE-BRASIL can contribute to identifying solutions for missed nursing care.
Electronic transport coefficients from ab initio simulations and application to dense liquid hydrogen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Holst, Bastian; French, Martin; Redmer, Ronald

2011-06-15

Using Kubo's linear response theory, we derive expressions for the frequency-dependent electrical conductivity (Kubo-Greenwood formula), thermopower, and thermal conductivity in a strongly correlated electron system. These are evaluated within ab initio molecular dynamics simulations in order to study the thermoelectric transport coefficients in dense liquid hydrogen, especially near the nonmetal-to-metal transition region. We also observe significant deviations from the widely used Wiedemann-Franz law, which is strictly valid only for degenerate systems, and give an estimate for its valid scope of application toward lower densities.
Prediction of friction coefficients for gases

NASA Technical Reports Server (NTRS)

Taylor, M. F.

1969-01-01

Empirical relations are used for correlating laminar and turbulent friction coefficients for gases, with large variations in the physical properties, flowing through smooth tubes. These relations have been used to correlate friction coefficients for hydrogen, helium, nitrogen, carbon dioxide and air.
Translation, cultural adaptation and validation of the Diabetes Attitudes Scale - third version into Brazilian Portuguese 1

PubMed Central

Vieira, Gisele de Lacerda Chaves; Pagano, Adriana Silvino; Reis, Ilka Afonso; Rodrigues, Júlia Santos Nunes; Torres, Heloísa de Carvalho

2018-01-01

ABSTRACT Objective: to perform the translation, adaptation and validation of the Diabetes Attitudes Scale - third version instrument into Brazilian Portuguese. Methods: methodological study carried out in six stages: initial translation, synthesis of the initial translation, back-translation, evaluation of the translated version by the Committee of Judges (27 Linguists and 29 health professionals), pre-test and validation. The pre-test and validation (test-retest) steps included 22 and 120 health professionals, respectively. The Content Validity Index, the analyses of internal consistency and reproducibility were performed using the R statistical program. Results: in the content validation, the instrument presented good acceptance among the Judges with a mean Content Validity Index of 0.94. The scale presented acceptable internal consistency (Cronbach’s alpha = 0.60), while the correlation of the total score at the test and retest moments was considered high (Polychoric Correlation Coefficient = 0.86). The Intra-class Correlation Coefficient, for the total score, presented a value of 0.65. Conclusion: the Brazilian version of the instrument (Escala de Atitudes dos Profissionais em relação ao Diabetes Mellitus) was considered valid and reliable for application by health professionals in Brazil. PMID:29319739
Validity and reliability of an adapted Thai version of Scoliosis Research Society-22 questionnaire for adolescent idiopathic scoliosis.

PubMed

Sathira-Angkura, Vera; Pithankuakul, Kongkit; Sakulpipatana, Susana; Piyaskulkaew, Chaiwat; Kunakornsawat, Sombat

2012-04-20

Cross-sectional observational study to investigate psychometric properties of an adapted Thai version of the refined Scoliosis Research Society-22 (SRS-22) questionnaire. To evaluate the reliability and validity of the adapted Thai version of the refined SRS-22 questionnaire. The SRS-22 questionnaire is a valid instrument for assessing the health-related quality of life for patients with adolescent idiopathic scoliosis. Recently, the questionnaire has been translated and validated in many languages for non-English-speaking countries. Translation/retranslation of the English version of the SRS-22 was conducted, and the cross-cultural adaptation process was performed. The Thai version SRS-22 and previously validated Thai version Short-Form survey version 2.0 (SF-36V2) questionnaires were administered to 77 patients with adolescent idiopathic scoliosis who had surgical treatment. Fifty-eight patients (52 adolescent girls) had filled out the first set of questionnaires. Thirty patients of the first-time responders completed the second set of questionnaires. The mean age at the time of operation was 14.6 years and the mean age at the time of the final follow-up was 18.7 years. The mean preoperative scoliosis curve magnitude was 55.4° (range, 30°-95°) and postoperative curve magnitude was 20.1° (range, 0°-60°). Internal consistency was determined with Cronbach α coefficient. Intraclass correlation coefficient was used for test-retest reliability. Concurrent validity was evaluated by comparing SRS-22 domains with relevant domains in the SF-36V2 questionnaire, using the Pearson correlation coefficient. The mean overall Cronbach α coefficient of the adapted Thai version SRS-22 was 0.76. The 2 of corresponding domains (mental health = 0.80 and self-image = 0.83) had satisfactory internal consistency and the remaining domains (pain = 0.78; function/activity = 0.74; and satisfaction = 0.76) were good. The intraclass correlation coefficient for 5 domains was ranged from
Testing reliability and validity of oral impacts on daily performances for Chinese-speaking elderly Singaporeans.

PubMed

Nair, Rahul; Tsakos, Georgios; Yee Ting Fai, Robert

2016-12-01

To cross-culturally adapt the oral impacts on daily performance (OIDP) and assess its reliability and validity on Chinese-speaking community dwelling elderly Singaporeans. There are no previous reports of valid oral health-related quality of life instruments for elderly Singaporeans or perceived conditions associated with impacts reported in OIDP among the Singaporean elders. The OIDP was translated from English to Chinese and then back translated. The OIDP questionnaire along with questions related to overall quality of life and self-rated dental health was administered to 202 Chinese-speaking elderly Singaporeans by trained interviewers, and it was repeated after 1 month. Test-retest reliability was assessed using intraclass correlation coefficient; internal consistency was established using Cronbach's alpha, and construct validity using correlation coefficients with self-reported oral health-related and global quality of life measures. In addition, Kruskal-Wallis tests assessed differences in the OIDP score between different subjective health and global quality of life groups. The median age of participants was 75 years. About 19% reported oral impacts and difficulty eating was the most prevalent oral impact. Internal consistency was good with a Cronbach's alpha of 0.75, and the intraclass correlation coefficient was 0.75 (0.67-0.81). OIDP was significantly correlated with all measures of self-reported oral health and global ratings of quality of life, with correlation coefficients ranging between 0.15 and 0.52. Groups with worse perceptions about their health and quality of life had significantly higher OIDP scores. The OIDP showed successful reliability and validity for its use among Chinese-speaking older Singaporeans. © 2015 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.
[Development and validation of the Chinese version of modified body imgae scale in Chinese population].

PubMed

Gao, X X; Zhu, L; Yu, S J; Xu, T

2018-02-25

Objective: To develop the Chinese version of modified body image scale (MBIS) questionnaires, and to validate them in Chinese population. Methods: The original English MBIS questionnaire was translated into Chinese, following the WHO cross-cultural adaptation of health-related quality of life measures. The reliability and validity of the Chinese version of MBIS questionnaires were evaluated in Chinese population, MRKH syndrome patients. Results: Totally 50 patients with MRKH syndrome completed the MBIS and short-form 12-item health survey (SF-12) questionnaires. The Cronbach's alpha of MBIS was 0.741, intraclass correlation coefficients were 0.472-0.815 ( P< 0.01). MBIS scores were positively correlated with SF-12 scores (Spearman correlation coefficient was-0.409, P< 0.01) . Factor analysis showed that MBIS had one common factor. Conclusion: Chinese version of MBIS has high reliability and validity in Chinese population, therefore is suitable for clinic and research.
[A Validation Study of the Modified Korean Version of Ethical Leadership at Work Questionnaire (K-ELW)].

PubMed

Kim, Jeong-Eon; Park, Eun-Jun

2015-04-01

The purpose of this study was to validate the Korean version of the Ethical Leadership at Work questionnaire (K-ELW) that measures RNs' perceived ethical leadership of their nurse managers. The strong validation process suggested by Benson (1998), including translation and cultural adaptation stage, structural stage, and external stage, was used. Participants were 241 RNs who reported their perceived ethical leadership using both the pre-version of K-ELW and a previously known Ethical Leadership Scale, and interactional justice of their managers, as well as their own demographics, organizational commitment and organizational citizenship behavior. Data analyses included descriptive statistics, Pearson correlation coefficients, reliability coefficients, exploratory factor analysis, and confirmatory factor analysis. SPSS 19.0 and Amos 18.0 versions were used. A modified K-ELW was developed from construct validity evidence and included 31 items in 7 domains: People orientation, task responsibility fairness, relationship fairness, power sharing, concern for sustainability, ethical guidance, and integrity. Convergent validity, discriminant validity, and concurrent validity were supported according to the correlation coefficients of the 7 domains with other measures. The results of this study provide preliminary evidence that the modified K-ELW can be adopted in Korean nursing organizations, and reliable and valid ethical leadership scores can be expected.

Oxford Shoulder Score: A Cross-Cultural Adaptation and Validation Study of the Persian Version in Iran.

PubMed

Ebrahimzadeh, Mohammad H; Birjandinejad, Ali; Razi, Shiva; Mardani-Kivi, Mohsen; Reza Kachooei, Amir

2015-09-01

Oxford shoulder score is a specific 12-item patient-reported tool for evaluation of patients with inflammatory and degenerative disorders of the shoulder. Since its introduction, it has been translated and culturally adapted in some Western and Eastern countries. The aim of this study was to translate the Oxford Shoulder Score (OSS) in Persian and to test its validity and reliability in Persian speaking population in Iran. One hundred patients with degenerative or inflammatory shoulder problem participated in the survey in 2012. All patients completed the Persian version of OSS, Persian DASH and the SF-36 for testing validity. Randomly, 37 patients filled out the Persian OSS again three days after the initial visit to assess the reliability of the questionnaire. Cronbach's alpha coefficient was 0.93. The intraclass correlation coefficient was 0.93. In terms of validity, there was a significant correlation between the Persian OSS and DASH and SF-36 scores (P < 0.001). The Persian version of the OSS proved to be a valid, reliable, and reproducible tool as demonstrated by high Cronbach's alpha and Pearson's correlation coefficients. The Persian transcript of OSS is administrable to Persian speaking patients with shoulder condition and it is understandable by them.
The validity and reliability of the Persian version of the Revised Fibromyalgia Impact Questionnaire.

PubMed

Ghavidel Parsa, Banafsheh; Amir Maafi, Alireza; Haghdoost, Afrooz; Arabi, Yasaman; Khojamli, Monire; Chatrnour, Gelayol; Bidari, Ali

2014-02-01

The Revised Fibromyalgia Impact Questionnaire (FIQR), an updated version of the Fibromyalgia Impact Questionnaire (FIQ) achieved a better balance among different domains (i.e., function, overall impact, and symptom severity) and attempts to address the limitations of FIQ. As there is no Persian version of the FIQR available, we aimed to investigate the validity and reliability of a Persian translation of the FIQR in Iranian patients. After translating the FIQR into Persian, it was administered to 77 female patients with fibromyalgia syndrome. All of the patients filled out the questionnaire together with a Persian version of the FIQ, short form-12 (SF-12). The tender-point count was also calculated. One week later, FM patients filled out the Persian FIQR at their second visit. Reliability was analyzed by internal consistency and reproducibility including Cronbach's α coefficient and intra-class correlation coefficient. Construct validity was evaluated by Spearman's correlation coefficient and Pearson's correlation coefficient. Statistical analysis was performed using SPSS for Windows version 17.0. All patients included in this study were female, and the mean age was 38.23 ± 10.68 years. The total scores of the FIQR and FIQ were 49.77 ± 18.27 and 54.05 ± 14.00 that were closely correlated (r = 0.63, p < 0.01), and each of the three domains of the Persian FIQR was also correlated well with the three related FIQ domains (r = 0.36-0.63, p < 0.01). Also some significant inverse correlations of FIQR with quality-of-life (assessed by SF-12) domains and items were found. Cronbach's α was 0.87 for FIQR in the first visit. The Persian FIQR showed adequate reliability and validity. This instrument can be used in the clinical evaluation of Iranian patients with fibromyalgia.
Validation of Pooled Whole-Genome Re-Sequencing in Arabidopsis lyrata.

PubMed

Fracassetti, Marco; Griffin, Philippa C; Willi, Yvonne

2015-01-01

Sequencing pooled DNA of multiple individuals from a population instead of sequencing individuals separately has become popular due to its cost-effectiveness and simple wet-lab protocol, although some criticism of this approach remains. Here we validated a protocol for pooled whole-genome re-sequencing (Pool-seq) of Arabidopsis lyrata libraries prepared with low amounts of DNA (1.6 ng per individual). The validation was based on comparing single nucleotide polymorphism (SNP) frequencies obtained by pooling with those obtained by individual-based Genotyping By Sequencing (GBS). Furthermore, we investigated the effect of sample number, sequencing depth per individual and variant caller on population SNP frequency estimates. For Pool-seq data, we compared frequency estimates from two SNP callers, VarScan and Snape; the former employs a frequentist SNP calling approach while the latter uses a Bayesian approach. Results revealed concordance correlation coefficients well above 0.8, confirming that Pool-seq is a valid method for acquiring population-level SNP frequency data. Higher accuracy was achieved by pooling more samples (25 compared to 14) and working with higher sequencing depth (4.1× per individual compared to 1.4× per individual), which increased the concordance correlation coefficient to 0.955. The Bayesian-based SNP caller produced somewhat higher concordance correlation coefficients, particularly at low sequencing depth. We recommend pooling at least 25 individuals combined with sequencing at a depth of 100× to produce satisfactory frequency estimates for common SNPs (minor allele frequency above 0.05).
Reliability and validity of an audio signal modified shuttle walk test.

PubMed

Singla, Rupak; Rai, Richa; Faye, Abhishek Anil; Jain, Anil Kumar; Chowdhury, Ranadip; Bandyopadhyay, Debdutta

2017-01-01

The audio signal in the conventionally accepted protocol of shuttle walk test (SWT) is not well-understood by the patients and modification of the audio signal may improve the performance of the test. The aim of this study is to study the validity and reliability of an audio signal modified SWT, called the Singla-Richa modified SWT (SWTSR), in healthy normal adults. In SWTSR, the audio signal was modified with the addition of reverse counting to it. A total of 54 healthy normal adults underwent conventional SWT (CSWT) at one instance and two times SWTSRon the same day. The validity was assessed by comparing outcomes of the SWTSRto outcomes of CSWT using the Pearson correlation coefficient and Bland-Altman plot. Test-retest reliability of SWTSRwas assessed using the intraclass correlation coefficient (ICC). The acceptability of the modified test in comparison to the conventional test was assessed using Likert scale. The distance walked (mean ± standard deviation) in the CSWT and SWTSRtest was 853.33 ± 217.33 m and 857.22 ± 219.56 m, respectively (Pearson correlation coefficient - 0.98; P < 0.001) indicating SWTSRto be a valid test. The SWTSRwas found to be a reliable test with ICC of 0.98 (95% confidence interval: 0.97-0.99). The acceptability of SWTSRwas significantly higher than CSWT. The SWTSRwith modified audio signal with reverse counting is a reliable as well as a valid test when compared with CSWT in healthy normal adults. It better understood by subjects compared to CSWT.
Validation of a short food frequency questionnaire to evaluate nutritional lifestyles in hypercholesterolemic patients.

PubMed

Béliard, Sophie; Coudert, Mathieu; Valéro, René; Charbonnier, Laurie; Duchêne, Emilie; Allaert, François André; Bruckert, Éric

2012-12-01

The purpose of our study was to develop and validate a short food frequency questionnaire which could assess the nutritional lifestyles of hypercholesterolemic patients consulting in daily practice. The questionnaire explores 11 nutrient categories. Hundred and thirty-one patients were recruited for the construct validity and 58 patients for the external validity in La Pitié Hospital, Paris. The reference method used was the diet history. To measure the internal consistency and to test the sensibility to change on a large scale, the questionnaire was used in an observational study conducted in Spain in 1048 moderate hypercholesterolemic patients. Psychometric analyses included construct validity, internal consistency, test-retest reliability, external validity and sensibility to change. Validation of the questionnaire indicated a good internal consistency (Cronbach Coefficient Alpha at 0.69) and test-retest reliability (intraclass correlation coefficient=0.89). The correlation between the scores of the FFQ and those of the diet history was significant with a Pearson correlation coefficient at 0.3 (P=0.029). The comparison between the ranking of the patients showed an agreement of 72% with a kappa of 0.48 [0.10; 0.69]. The sensibility to change was good with a score evolution improving one and four months after nutrition advices: 28.2% of patients ranked in group 1 at inclusion versus 61.3% (P<0.0001) at one month and 75.2% (P<0.0001) at four months. In conclusion, we developed and validated a food questionnaire for hypercholesterolemic patients, which can be used as a therapeutic education tool in daily practice or in clinical research. Copyright © 2012. Published by Elsevier Masson SAS.
The validation of the visual analogue scale for patient satisfaction after total hip arthroplasty.

PubMed

Brokelman, Roy B G; Haverkamp, Daniel; van Loon, Corné; Hol, Annemiek; van Kampen, Albert; Veth, Rene

2012-06-01

INTRODUCTION: Patient satisfaction becomes more important in our modern health care system. The assessment of satisfaction is difficult because it is a multifactorial item for which no golden standard exists. One of the potential methods of measuring satisfaction is by using the well-known visual analogue scale (VAS). In this study, we validated VAS for satisfaction. PATIENT AND METHODS: In this prospective study, we studied 147 patients (153 hips). The construct validity was measured using the Spearman correlation test that compares the satisfaction VAS with the Harris hip score, pain VAS at rest and during activity, Oxford hip score, Short Form 36 and Western Ontario McMaster Universities Osteoarthritis Index. The reliability was tested using the intra-class coefficient. RESULTS: The Pearson correlation test showed correlations in the range of 0.40-0.80. The satisfaction VAS had a high correlation between the pain VAS and Oxford hip score, which could mean that pain is one of the most important factors in patient satisfaction. The intra-class coefficient was 0.95. CONCLUSIONS: There is a moderate to mark degree of correlation between the satisfaction VAS and the currently available subjective and objective scoring systems. The intra-class coefficient of 0.95 indicates an excellent test-retest reliability. The VAS satisfaction is a simple instrument to quantify the satisfaction of a patient after total hip arthroplasty. In this study, we showed that the satisfaction VAS has a good validity and reliability.
Spectral regression and correlation coefficients of some benzaldimines and salicylaldimines in different solvents

NASA Astrophysics Data System (ADS)

Hammud, Hassan H.; Ghannoum, Amer; Masoud, Mamdouh S.

2006-02-01

Sixteen Schiff bases obtained from the condensation of benzaldehyde or salicylaldehyde with various amines (aniline, 4-carboxyaniline, phenylhydrazine, 2,4-dinitrophenylhydrazine, ethylenediamine, hydrazine, o-phenylenediamine and 2,6-pyridinediamine) are studied with UV-vis spectroscopy to observe the effect of solvents, substituents and other structural factors on the spectra. The bands involving different electronic transitions are interpreted. Computerized analysis and multiple regression techniques were applied to calculate the regression and correlation coefficients based on the equation that relates peak position λmax to the solvent parameters that depend on the H-bonding ability, refractive index and dielectric constant of solvents.
Validation of the MESSi among adult workers and young students: General health and personality correlates.

PubMed

Díaz-Morales, Juan F; Randler, Christoph; Arrona-Palacios, Arturo; Adan, Ana

2017-01-01

The aim of this study was to provide validity for the Spanish version of the Morningness-Eveningness-Stability Scale - improved (MESSi), a novel evolved assessment of circadian typology which considers the subjective phase and amplitude by morning affect (MA), eveningness (EV) and distinctness (DI; subjective amplitude) sub-scales. Convergence validity of the MESSi with the reduced Morningness-Eveningness Questionnaire (rMEQ) and relationships with the General Health Questionnaire (GHQ-12) and sensitivity to reward and punishment (SR and SP) were analyzed. Two different Spanish samples, young undergraduate students (n = 891, 18-30 years) and adult workers (n = 577, 31-65 years) participated in this study. Exploratory structural equation modeling (ESEM) of MESSi displayed acceptable fit of a three-factors measurement model. Percentiles of the MA, EV and DI sub-scales were obtained for students and adults. The MESSi showed good convergence validity with the rMEQ scores, with a higher correlation coefficient between MA, EV and lower with DI sub-scales. In both, young students and adult workers, MA was negatively related with the GHQ-12 and SP, but the percentage of explained variance (6% and 3%) was lower than the positive correlations between DI, the GHQ-12 and SP (20% and 13%). Morning types presented higher MA and lower EV scores than the other two typologies in both students and adult workers, whereas only differences in DI were found among students (lowest in evening type). Candidates to psychological symptoms and mental disorders ("true cases"), with the clinical cut-off criteria of the GHQ-12, showed lower MA and higher DI in students, whereas only DI was higher for "true cases" among adults. These results supported that subjective amplitude is a factor related to, but also differentiated of, morningness-eveningness (preferred time for a certain activity). The measure of amplitude might be more important than circadian phase in health consequences.
Temporal behavior of the effective diffusion coefficients for transport in heterogeneous saturated aquifers

NASA Astrophysics Data System (ADS)

Suciu, N.; Vamos, C.; Vereecken, H.; Vanderborght, J.; Hardelauf, H.

2003-04-01

When the small scale transport is modeled by a Wiener process and the large scale heterogeneity by a random velocity field, the effective coefficients, Deff, can be decomposed as sums between the local coefficient, D, a contribution of the random advection, Dadv, and a contribution of the randomness of the trajectory of plume center of mass, Dcm: Deff=D+Dadv-Dcm. The coefficient Dadv is similar to that introduced by Taylor in 1921, and more recent works associate it with the thermodynamic equilibrium. The ``ergodic hypothesis'' says that over large time intervals Dcm vanishes and the effect of the heterogeneity is described by Dadv=Deff-D. In this work we investigate numerically the long time behavior of the effective coefficients as well as the validity of the ergodic hypothesis. The transport in every realization of the velocity field is modeled with the Global Random Walk Algorithm, which is able to track as many particles as necessary to achieve a statistically reliable simulation of the process. Averages over realizations are further used to estimate mean coefficients and standard deviations. In order to remain in the frame of most of the theoretical approaches, the velocity field was generated in a linear approximation and the logarithm of the hydraulic conductivity was taken to be exponential decaying correlated with variance equal to 0.1. Our results show that even in these idealized conditions, the effective coefficients tend to asymptotic constant values only when the plume travels thousands of correlations lengths (while the first order theories usually predict Fickian behavior after tens of correlations lengths) and that the ergodicity conditions are still far from being met.
The City of Hope-Quality of Life-Ostomy Questionnaire: Persian Translation and Validation

PubMed Central

Anaraki, F; Vafaie, M; Behboo, R; Esmaeilpour, S; Maghsoodi, N; Safaee, A; Grant, M

2014-01-01

Background: Since there is no disease-specific instrument for measuring quality-of-life (QOL) in Ostomy patients in Persian language. Aim: This study was designed to translate and evaluate the validity and reliability of City of Hope-quality of life-Ostomy questionnaire (COH-QOL-Ostomy questionnaire). Subjects and Methods: This study was designed as cross-sectional study. Reliability of the subscales and the summary scores were demonstrated by intra-class correlation coefficients. Pearson's correlations of an item with its own scale and other scales were calculated to evaluated convergent and discriminant validity. Clinical validity was also evaluated by known-group comparisons. Results: Cronbach's alpha coefficient for all subscales was about 0.70 or higher. Results of interscale correlation were satisfactory and each subscale only measured a single and specified trait. All subscales met the standards of convergent and discriminant validity. Known group comparison analysis showed significant differences in social and spiritual well-being. Conclusion: The findings confirmed the reliability and validity of Persian version of COH-QOL-Ostomy questionnaire. The instrument was also well received by the Iranian patients. It can be considered as a valuable instrument to assess the different aspects of health related quality-of-life in Ostomy patients and used in clinical research in the future. PMID:25221719
The city of hope-quality of life-ostomy questionnaire: persian translation and validation.

PubMed

Anaraki, F; Vafaie, M; Behboo, R; Esmaeilpour, S; Maghsoodi, N; Safaee, A; Grant, M

2014-07-01

Since there is no disease-specific instrument for measuring quality-of-life (QOL) in Ostomy patients in Persian language. This study was designed to translate and evaluate the validity and reliability of City of Hope-quality of life-Ostomy questionnaire (COH-QOL-Ostomy questionnaire). This study was designed as cross-sectional study. Reliability of the subscales and the summary scores were demonstrated by intra-class correlation coefficients. Pearson's correlations of an item with its own scale and other scales were calculated to evaluated convergent and discriminant validity. Clinical validity was also evaluated by known-group comparisons. Cronbach's alpha coefficient for all subscales was about 0.70 or higher. Results of interscale correlation were satisfactory and each subscale only measured a single and specified trait. All subscales met the standards of convergent and discriminant validity. Known group comparison analysis showed significant differences in social and spiritual well-being. The findings confirmed the reliability and validity of Persian version of COH-QOL-Ostomy questionnaire. The instrument was also well received by the Iranian patients. It can be considered as a valuable instrument to assess the different aspects of health related quality-of-life in Ostomy patients and used in clinical research in the future.
Psychometric validation of the Chinese version of the Illness Perception Questionnaire-Revised for women with stress urinary incontinence.

PubMed

Fan, Yijun; Huang, Zhaohui; Zhang, Dazhao; Chang, Jun; Jia, Yun; He, Shuihong; Wei, Bing

2017-08-01

The aim of this study was to examine the reliability and validity of the Illness Perception Questionnaire-Revised (IPQ-R) in patients with stress urinary incontinence (SUI). A total of 256 patients with SUI and 76 patients with myoma of the uterus were recruited to complete the Chinese IPQ-R. For the reliability, the key tests included Cronbach's α coefficient and intraclass correlation coefficients. For the validity, the key tests included factor analysis, Spearman's correlation coefficient, and the Student's t-test. Cronbach's α values ranged from 0.68 to 0.90 for each subscale and the intraclass correlation coefficients ranged from 0.80 to 0.94. The results of the confirmatory factor analysis showed that the seven-factor structure as proposed by the original IPQ-R fit the data poorly. Although removal of three items improved the model's fit, the goodness-of-fit statistics were still below acceptable standards. We identified an acceptable seven-factor solution from the 38 items on Illness Beliefs using an exploratory factor analysis (EFA), which accounted for 68.12% of the variance. For the concurrent validity, Consequences and Emotional Representation both had good correlations with anxiety and depression (r = 0.52-0.62) and better quality of life (r = 0.58-0.73). The inter-correlation coefficient of the seven factors ranged from 0.05 to 0.59, suggesting acceptable discriminant validity. There were significant differences on the scale scores of Disease Identity (t = 9.39, P < 0.01), Timeline-Acute/Chronic (t = 3.69, P < 0.01), Consequences (t = 4.53, P < 0.01), Illness Coherence (t = 7.73, P < 0.01), Timeline-Cyclical (t = 6.48, P < 0.01), Emotional Representation (t = 6.40, P < 0.01), and Cause (t = 4.29, P < 0.01) between the patients with SUI and with myoma of the uterus, which also indicated acceptable discriminant validity. The findings of this study supported the Chinese IPQ-R as being a reliable and valid tool for measuring illness
Mental Task Classification Scheme Utilizing Correlation Coefficient Extracted from Interchannel Intrinsic Mode Function.

PubMed

Rahman, Md Mostafizur; Fattah, Shaikh Anowarul

2017-01-01

In view of recent increase of brain computer interface (BCI) based applications, the importance of efficient classification of various mental tasks has increased prodigiously nowadays. In order to obtain effective classification, efficient feature extraction scheme is necessary, for which, in the proposed method, the interchannel relationship among electroencephalogram (EEG) data is utilized. It is expected that the correlation obtained from different combination of channels will be different for different mental tasks, which can be exploited to extract distinctive feature. The empirical mode decomposition (EMD) technique is employed on a test EEG signal obtained from a channel, which provides a number of intrinsic mode functions (IMFs), and correlation coefficient is extracted from interchannel IMF data. Simultaneously, different statistical features are also obtained from each IMF. Finally, the feature matrix is formed utilizing interchannel correlation features and intrachannel statistical features of the selected IMFs of EEG signal. Different kernels of the support vector machine (SVM) classifier are used to carry out the classification task. An EEG dataset containing ten different combinations of five different mental tasks is utilized to demonstrate the classification performance and a very high level of accuracy is achieved by the proposed scheme compared to existing methods.
Validation of the Korean Version of the Mini-Sleep Questionnaire-Insomnia in Korean College Students.

PubMed

Kim, Hee-Ju

2017-03-01

This study aimed to evaluate the reliability and validity of the Korean version of the Mini-Sleep Questionnaire-Insomnia in Korean college students. A total of 470 students from six nursing colleges in South Korea participated in the study. The translation and linguistic validation of the Mini-Sleep Questionnaire-Insomnia was performed based on guidelines. The Pittsburgh Sleep Quality Index and the Perceived Stress Scale were used to validate the measure. Cronbach α, item-total correlation for internal consistency reliability and intraclass correlation coefficient for test-retest reliability were evaluated. Exploratory factor analysis for construct validity, Pearson's correlation with the Pittsburgh Sleep Quality Index and the Perceived Stress Scale for concurrent validity, and the receiver operating character curve for predictive validity were assessed. The 4-item Mini-Sleep Questionnaire-Insomnia had a Cronbach α of .69 and the item-total correlations were higher than .30. Cronbach α increased to .73 if the item assessing the use of sleeping pills and tranquilizers was deleted. This item had marked skewness and kurtosis issues. Factor analysis indicated unidimensionality, explaining 53.0% of the total variance. The measure showed high test-retest reliability (i.e., intraclass correlation coefficient = .84), acceptable concurrent validity (r with the Pittsburg Sleep Quality Index = .69; r with the Perceived Stress Scale = .31) and predictive validity [area under curve = .85; 95% confidence interval (0.81, 0.90)]. The Mini-Sleep Questionnaire-Insomnia showed acceptable reliability and validity. Yet, the limited distribution in sleep medications warrants further evaluations in the clinical population. Copyright © 2017. Published by Elsevier B.V.
Evaluating the validity and reliability of the V-scale instrument (Turkish version) used to determine nurses' attitudes towards vital sign monitoring.

PubMed

Ertuğ, Nurcan

2018-06-01

The aim of this study was to determine the validity and reliability of the Turkish version of the V-scale, which measures nurses' attitudes towards vital signs monitoring in the detection of clinical deterioration. This validity and reliability study was conducted at a tertiary hospital in Ankara, Turkey, in 2016. A total of 169 ward nurses participated in the study. Exploratory factor analysis, Cronbach's alpha coefficient, and the intraclass correlation coefficient were used to determine the validity and reliability of the scale. A 5-factor, 16-item scale explained 60.823% of the total variance according to the validity analysis. Our version matched the original scale in terms of the number of items and factor structure. Cronbach's alpha coefficient of the Turkish version of the V-scale was 0.764. The test-retest reliability results were 0.855 for the overall intraclass correlation coefficient, and the t-test result was P > 0.05. The V-scale is a reliable and valid instrument to measure Turkish nurses' attitudes towards vital signs monitoring in the detection of clinical deterioration. © 2018 John Wiley & Sons Australia, Ltd.
Transcultural adaptation and validation of the “Hip and Knee” questionnaire into Spanish

PubMed Central

2014-01-01

Background The purpose of the present study is to translate and validate the “Hip and Knee Outcomes Questionnaire”, developed in English, into Spanish. The ‘Hip and Knee Outcomes Questionnaire is a questionnaire planned to evaluate the impact in quality of life of any problem related to the human musculoskeletal system. 10 scientific associations developed it. Methods The questionnaire underwent a validated translation/retro-translation process. Patients undergoing primary knee arthroplasty, before and six months postoperative, tested the final version in Spanish. Psychometric properties of feasibility, reliability, validity and sensitivity to change were assessed. Convergent validity with SF-36 and WOMAC questionnaires was evaluated. Results 316 patients were included. Feasibility: a high number of missing items in questions 3, 4 and 5 were observed. The number of patients with a missing item was 171 (51.35%) in the preoperative visit and 139 (44.0%) at the postoperative. Internal validity: revision of coefficients in the item-rest correlation recommended removing question 6 during the preoperative visit (coefficient <0.20). Convergent validity: coefficients of correlation with WOMAC and SF-36 scales confirm the questionnaire’s validity. Sensitivity to change: statistically significant differences were found between the mean scores of the first visit compared to the postoperative. Conclusion The proposed translation to Spanish of the ‘Hip and Knee Questionnaire’ is found to be reliable, valid and sensible to changes produced at the clinical practice of patients undergoing primary knee arthroplasty. However, some changes at the completion instructions are recommended. Level of evidence: Level I. Prognostic study. PMID:24885248
Transcultural adaptation and validation of the patient empowerment in long-term conditions questionnaire.

PubMed

Garcimartin, Paloma; Comin-Colet, Josep; Delgado-Hito, Pilar; Badosa-Marcé, Neus; Linas-Alonso, Anna

2017-05-04

Patient empowerment is a key element to improve the results in health, increase satisfaction amongst users and obtain higher treatment compliance. The main objective of this study is to validate the Spanish version of the questionnaire "Patient empowerment in long-term conditions" which evaluates the patients' level of empowerment of chronic diseases. The secondary objective is to identify factors which predict basal empowerment and changes (improvement or deterioration) in patients with Heart Failure (HF). An observational and prospective design of psychometric type to validate a questionnaire (aim 1) and a prospective study of cohorts (aim 2). The study will include 121 patients with confirmed diagnosis of HF. Three measurements (basal, at 15 days and at 3 months) will be carried out: quality of life, self-care and empowerment. Descriptive and inferential analyses will be used. For the first aim of the study (validation), the test-retest reproducibility will be assessed through intraclass correlation coefficient; internal consistency will be assessed through Cronbach's alpha coefficient; construct validity through Pearson's correlation coefficient; and sensibility to change through effect size coefficient. Set a valid questionnaire to measure the level of empowerment of patients with chronic diseases could be an effective tool to assess the results from the provision of the health care services. It will also allow us to identify at an early stage, those groups of patients with a low level of empowerment. Hence, they could become a risk group due to poor management of the disease, with a high rate of decompensation and a higher use rate of the health system resources.
The Validation of a Case-Based, Cumulative Assessment and Progressions Examination

PubMed Central

Coker, Adeola O.; Copeland, Jeffrey T.; Gottlieb, Helmut B.; Horlen, Cheryl; Smith, Helen E.; Urteaga, Elizabeth M.; Ramsinghani, Sushma; Zertuche, Alejandra; Maize, David

2016-01-01

Objective. To assess content and criterion validity, as well as reliability of an internally developed, case-based, cumulative, high-stakes third-year Annual Student Assessment and Progression Examination (P3 ASAP Exam). Methods. Content validity was assessed through the writing-reviewing process. Criterion validity was assessed by comparing student scores on the P3 ASAP Exam with the nationally validated Pharmacy Curriculum Outcomes Assessment (PCOA). Reliability was assessed with psychometric analysis comparing student performance over four years. Results. The P3 ASAP Exam showed content validity through representation of didactic courses and professional outcomes. Similar scores on the P3 ASAP Exam and PCOA with Pearson correlation coefficient established criterion validity. Consistent student performance using Kuder-Richardson coefficient (KR-20) since 2012 reflected reliability of the examination. Conclusion. Pharmacy schools can implement internally developed, high-stakes, cumulative progression examinations that are valid and reliable using a robust writing-reviewing process and psychometric analyses. PMID:26941435
2pBAb5. Validation of three-dimensional strain tracking by volumetric ultrasound image correlation in a pubovisceral muscle model

PubMed Central

Nagle, Anna S.; Nageswaren, Ashok R.; Haridas, Balakrishna; Mast, T. D.

2014-01-01

Little is understood about the biomechanical changes leading to pelvic floor disorders such as stress urinary incontinence. In order to measure regional biomechanical properties of the pelvic floor muscles in vivo, a three dimensional (3D) strain tracking technique employing correlation of volumetric ultrasound images has been implemented. In this technique, local 3D displacements are determined as a function of applied stress and then converted to strain maps. To validate this approach, an in vitro model of the pubovisceral muscle, with a hemispherical indenter emulating the downward stress caused by intra-abdominal pressure, was constructed. Volumetric B-scan images were recorded as a function of indenter displacement while muscle strain was measured independently by a sonomicrometry system (Sonometrics). Local strains were computed by ultrasound image correlation and compared with sonomicrometry-measured strains to assess strain tracking accuracy. Image correlation by maximizing an exponential likelihood function was found more reliable than the Pearson correlation coefficient. Strain accuracy was dependent on sizes of the subvolumes used for image correlation, relative to characteristic speckle length scales of the images. Decorrelation of echo signals was mapped as a function of indenter displacement and local tissue orientation. Strain measurement accuracy was weakly related to local echo decorrelation. PMID:24900165
Endometrial cancer: correlation of apparent diffusion coefficient (ADC) with tumor cellularity and tumor grade.

PubMed

Kishimoto, Keiko; Tajima, Shinya; Maeda, Ichiro; Takagi, Masayuki; Ueno, Takahiko; Suzuki, Nao; Nakajima, Yasuo

2016-08-01

Diffusion-weighted imaging (DWI) and the apparent diffusion coefficient (ADC) are widely used for detecting uterine endometrial cancer. The relationships between ADC values and pathological features of endometrial cancer have not yet been established. To investigate whether ADC values of endometrial cancer vary according to histologic tumor cellularity and tumor grade. We retrospectively reviewed 30 pathologically confirmed endometrial cancers. All patients underwent conventional non-enhanced magnetic resonance imaging (MRI) and DWI procedures, and ADC values were calculated. Tumor cellularity was evaluated by counting cancer cells in three high-power ( × 400) fields. The correlation between ADC values and tumor cellularity was assessed using Pearson's correlation coefficient test for statistical analysis. The mean ± standard deviation (SD) ADC value ( ×10(-3) mm(2)/s) of endometrial cancer was 0.85 ± 0.22 (range, 0.55-1.71). The mean ± SD tumor cellularity was 528.36 ± 16.89 (range, 298.0-763.6). ADC values were significantly inversely correlated with tumor cellularity. No significant relationship was observed between ADC values and tumor grade (mean ADC values: G1, 0.88 ± 0.265 × 10(-3) mm(2)/s; G2, 0.80 ± 0.178 × 10(-3) mm(2)/s; G3, 0.81 ± 0.117 × 10(-3) mm(2)/s). There is a significant inverse relationship between ADC values and tumor cellularity in endometrial cancer. No significant differences in average ADC value were observed between G1, G2, and G3 tumors. However, the lower the tumor grade, the wider the SD. © The Foundation Acta Radiologica 2015.

Validation of the Hindi version of National Institute of Health Stroke Scale.

PubMed

Prasad, Kameshwar; Dash, Deepa; Kumar, Amit

2012-01-01

To determine the reliability and validity of the National Institute of Health Stroke Scale (NIHSS) with the Hindi and Indian adaptation of items 9 and 10. NIHSS items 9 and 10 were modified and culturally adapted at All India Institute of Medical Sciences (AIIMS) and the resulting version was termed as Hindi version (HV-NIHSS). HV-NIHSS was applied by two independent investigators on 107 patients with stroke. Inter-observer agreement and intra-class correlation coefficients were calculated. The predictive validity of the HV-NIHSS was calculated using functional outcome after three months in the form of modified Rankin Scale (mRS) and Barthel Index (BI). The study included 107 patients of stroke recruited from a tertiary referral hospital at Delhi between November 1, 2009, and October 1, 2010; the mean age of these patients was 56.26±13.84 years and 65.4% of them had suffered ischemic stroke. Inter-rater reliability was high between the two examiners, with Pearson's r ranging from 0.72 to 0.99 for the 15 items on the Scale. Intra-class correlation coefficient for the total score was 0.995 (95% CI-0.993-0.997). Concurrent construct validity was established between HV-NIHSS and baseline Glasgow Coma Scale, with a high correlation (Spearman coefficient = -0.863, P<.001). Predictive validity was also established with BI at three months (Spearman's rho: -0.829, P<.001) and with mRS at three months (Spearman's rho: 0.851, P<0.001). This study shows that a Hindi language version of the NIHSS developed at AIIMS appears reliable and valid when applied to a Hindi-speaking population.
Chinese adaptation and validation of the patellofemoral pain severity scale.

PubMed

Cheung, Roy T H; Ngai, Shirley P C; Lam, Priscillia L; Chiu, Joseph K W; Fung, Eric Y H

2013-05-01

This study validated the Patellofemoral Pain Severity Scale translated into Chinese. The Chinese Patellofemoral Pain Severity Scale was translated from the original English version following standard forward and backward translation procedures recommended by the International Society for Pharmacoeconomics and Outcomes Research. The survey was then conducted in clinical settings by a questionnaire comprising the Chinese Patellofemoral Pain Severity Scale, Kujala Scale and Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Eighty-four Chinese reading patients with patellofemoral pain were recruited from physical therapy clinics. Internal consistency of the translated instrument was measured by Cronbach alpha. Convergent validity was examined by Spearman rank correlation coefficient (rho) tests by comparing its score with the validated Chinese version of the Kujala Scale and the WOMAC Osteoarthritis Index while the test-retest reliability was evaluated by administering the questionnaires twice. Cronbach alpha values of individual questions and their overall value were above 0.85. Strong association was found between the Chinese Patellofemoral Pain Severity Scale and the Kujala Scale (rho = -0.72, p < 0.001). Moderate correlation was also found between Chinese Patellofemoral Pain Severity Scale with the WOMAC Osteoarthritis Index (rho = 0.63, p < 0.001). Excellent test-retest reliability (Intraclass correlation coefficient = 0.98) was demonstrated. The Chinese translated version of the Patellofemoral Pain Severity Scale is a reliable and valid instrument for patients with patellofemoral pain.
Validation of the Hebrew version of the Burn Specific Health Scale-Brief questionnaire.

PubMed

Stavrou, Demetris; Haik, Josef; Wiser, Itay; Winkler, Eyal; Liran, Alon; Holloway, Samantha; Boyd, Julie; Zilinsky, Isaac; Weissman, Oren

2015-02-01

The Burns Specific Health Scale-Brief (BSHS-B) questionnaire is a suitable measurement tool for the assessment of general, physical, mental, and social health aspects of the burn survivor. To translate, culturally adapt and validate the BSHS-B to Hebrew (BSHS-H), and to investigate its psychometric properties. Eighty-six Hebrew speaking burn survivors filled out the BSHS-B and SF-36 questionnaires. Ten of them (11.63%) completed a retest. The psychometric properties of the scale were evaluated. Internal consistency, criterion validity, and construct validity were assessed using interclass correlation coefficient, Cronbach's alpha statistic, Spearman rank test, and Mann-Whitney U test respectively. BSHS-H Cronbach's alpha coefficient was 0.97. Test-retest interclass coefficients were between 0.81 and 0.98. BSHS-H was able to discriminate between facial burns, hand burns and burns >10% body surface area (p<0.05). BSHS-H and SF-36 were positively correlated (r(2)=0.667, p<0.01). BSHS-H is a reliable and valid instrument for use in the Israeli burn survivor population. The translation and cross-cultural adaptation of this disease specific scale allows future comparative international studies. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.
[Validation of the German version of the Oxford Elbow Score : A cross-sectional study].

PubMed

Marquardt, J; Schöttker-Königer, T; Schäfer, A

2016-08-01

Elbow complaints are complex problems leading to severe consequences for affected people and the healthcare system. The German version of the Oxford Elbow Score (OES) is the first German-speaking instrument that specifically measures elbow complaints from the patient's perspective and changes of their health status. The aim of this study is the validation of the German version of the OES. In this context the internal consistency and the construct validity were investigated. 59 patients with elbow complaints completed the German version of the OES, the DASH and the SF-36 in a cross-sectional study. The internal consistency was calculated with Cronbach's alpha coefficients. Spearman's correlation coefficients were used to confirm construct validity. Cronbach's alpha for pain, function and psychological subscales was 0.88, 0.81 and 0.90, respectively. The whole questionnaire presents a Cronbach's alpha value of 0.93. Convergent construct validity was confirmed with correlation coefficients containing values of -0.84, -0.77 and -0.82 compared to DASH and values ranging from 0.41 to 0.80 compared with the physical domains of the SF-36. The divergent construct validity presented values ranging from 0.07 to 0.20 with the SF-36 domains of "general health perception" and "mental health". The German OES is an internal consistent instrument with good convergent and divergent construct validity. Other aspects of the validity, the reliability and the responsiveness should be confirmed through further studies.
Correlation between standardized uptake value and apparent diffusion coefficient of neoplastic lesions evaluated with whole-body simultaneous hybrid PET/MRI.

PubMed

Rakheja, Rajan; Chandarana, Hersh; DeMello, Linda; Jackson, Kimberly; Geppert, Christian; Faul, David; Glielmi, Christopher; Friedman, Kent P

2013-11-01

The purpose of this study was to assess the correlation between standardized uptake value (SUV) and apparent diffusion coefficient (ADC) of neoplastic lesions in the use of a simultaneous PET/MRI hybrid system. Twenty-four patients with known primary malignancies underwent FDG PET/CT. They then underwent whole-body PET/MRI. Diffusion-weighted imaging was performed with free breathing and a single-shot spin-echo echo-planar imaging sequence with b values of 0, 350, and 750 s/mm(2). Regions of interest were manually drawn along the contours of neoplastic lesions larger than 1 cm, which were clearly identified on PET and diffusion-weighted images. Maximum SUV (SUVmax) on PET/MRI and PET/CT images, mean SUV (SUVmean), minimum ADC (ADCmin), and mean ADC (ADCmean) were recorded on PET/MR images for each FDG-avid neoplastic soft-tissue lesion with a maximum of three lesions per patient. Pearson correlation coefficient was used to asses the following relations: SUVmax versus ADCmin on PET/MR and PET/CT images, SUVmean versus ADCmean, and ratio of SUVmax to mean liver SUV (SUV ratio) versus ADCmin. A subanalysis of patients with progressive disease versus partial treatment response was performed with the ratio of SUVmax to ADCmin for the most metabolically active lesion. Sixty-nine neoplastic lesions (52 nonosseous lesions, 17 bone metastatic lesions) were evaluated. The mean SUVmax from PET/MRI was 7.0 ± 6.0; SUVmean, 5.6 ± 4.6; mean ADCmin, 1.10 ± 0.58; and mean ADCmean, 1.48 ± 0.72. A significant inverse Pearson correlation coefficient was found between PET/MRI SUVmax and ADCmin (r = -0.21, p = 0.04), between SUVmean and ADCmean (r = -0.18, p = 0.07), and between SUV ratio and ADCmin (r = -0.27, p = 0.01). A similar inverse Pearson correlation coefficient was found between the PET/CT SUVmax and ADCmin. Twenty of 24 patients had previously undergone PET/CT; five patients had a partial treatment response, and six had progressive disease according to Response Evaluation
[Validity, reliability, and acceptability of the scale of knowledge, attitude, and behavior of lifestyle intervention in a diabetes high-risk population].

PubMed

Wang, W J; Dong, J; Ren, Z P; Chen, B; He, W; Li, W D; Hao, Z W

2016-07-06

To evaluate the validity, reliability, and acceptability of the scale of knowledge, attitude, and behavior of lifestyle intervention in a diabetes high-risk population (HILKAB), and provide scientific evidence for its usage. By convenient sampling, we selected 406 individuals at high risk for diabetes for survey using the HILKAB. Pearson correlation coefficient, factor analysis, independent sampling, and t-test for high- and low-score groups were used to evaluate the content validity, construct validity, and discriminant validity of the scale. Reliability of the scale was evaluated by internal consistency, which included Cronbach's α coefficient, θ coefficient, Ω coefficient, and split-half reliability. Scale acceptability was evaluated by acceptance rate and completion time of the survey. In this study, 366 questionnaires (90.1%) was qnalified and the completion time was (8.62±2.79) minutes. Scores for knowledge, attitude, and behavior were 10.60±3.73, 26.56±3.58, 17.09±9.74, respectively. The scale had good face validity and content validity. The correlation coefficient of items and the dimension to which they belong was between 0.25 and 0.97, and the correlation coefficient of three dimensions and the entire scale was between 0.64 and 0.91, all with P<0.001. Factor analysis of the scale extracted eight common factors. The cumulative variance contribution rate was 65.23%, thereby reaching the 50% approved standard. Of 30 items there were 29 items with factor loadings ≥0.40, indicating the scale had good construct validity. For the high-score group, scores for knowledge, attitude, and behavior dimensions were 13.89±2.55, 29.56± 2.46, 28.05 ± 2.93, respectively, which were higher than those for the low-score group (7.67 ± 2.78, 23.89 ± 3.35, 6.25 ± 3.13); t-values were 55.14, 119.40, 95.29, respectively, with P<0.001. The scale consisted of three dimensions: knowledge, attitude, and behavior. The Cronbach's α coefficient was between 0.84 and 0
Validation of the French version of the Burn Specific Health Scale-Brief (BSHS-B) questionnaire.

PubMed

Gandolfi, S; Auquit-Auckbur, I; Panunzi, S; Mici, E; Grolleau, J-L; Chaput, B

2016-11-01

The Burn Specific Health Scale-Brief questionnaire is a widely validated tool for estimating the health related quality of life and for assessing the best multidisciplinary management of burn patients. The aim of this study was to translate the BSHS-B into French and to investigate its reliability and validity. According to the procedure proposed by the Scientific Advisory Committee of the Medical Outcomes Trust, the Burn Specific Health Scale-Brief (BSHS-B) was translated from the English version into French. In order to test the reliability of the French version of the BSHS-B, 53 burn patients French speakers completed the BSHS-B and SF-36 questionnaires from two to four years after burn. Ten of them have been re-tested at 6 months after the first evaluation. To evaluate clinical utility of the BSHS-F, internal consistency, construct validity (using SF-36) and stability in time were assessed using Cronbach's alpha statistic, Spearman rank test, and intra-class correlation coefficient respectively. The French version of the BSHS-B Cronbach's alpha coefficient was 0.93 and was >0.80 for all the sub-domains. French version of the BSHS-B and the SF-36 were positively correlated, all the associations were statistically significant (p<0.01). Intra-class correlation coefficients for test-retest ranged between 0.95 and 0.99 for the sub-domains. The intra-class correlation coefficient (ICC) for the total score was 0.98. The French version of the BSHS-B shows a robust rate of internal consistency, construct validity and stability in time, supporting its application in routine clinical practice as well as in international studies. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.
Translating and validating a Training Needs Assessment tool into Greek

PubMed Central

Markaki, Adelais; Antonakis, Nikos; Hicks, Carolyn M; Lionis, Christos

2007-01-01

Background The translation and cultural adaptation of widely accepted, psychometrically tested tools is regarded as an essential component of effective human resource management in the primary care arena. The Training Needs Assessment (TNA) is a widely used, valid instrument, designed to measure professional development needs of health care professionals, especially in primary health care. This study aims to describe the translation, adaptation and validation of the TNA questionnaire into Greek language and discuss possibilities of its use in primary care settings. Methods A modified version of the English self-administered questionnaire consisting of 30 items was used. Internationally recommended methodology, mandating forward translation, backward translation, reconciliation and pretesting steps, was followed. Tool validation included assessing item internal consistency, using the alpha coefficient of Cronbach. Reproducibility (test – retest reliability) was measured by the kappa correlation coefficient. Criterion validity was calculated for selected parts of the questionnaire by correlating respondents' research experience with relevant research item scores. An exploratory factor analysis highlighted how the items group together, using a Varimax (oblique) rotation and subsequent Cronbach's alpha assessment. Results The psychometric properties of the Greek version of the TNA questionnaire for nursing staff employed in primary care were good. Internal consistency of the instrument was very good, Cronbach's alpha was found to be 0.985 (p < 0.001) and Kappa coefficient for reproducibility was found to be 0.928 (p < 0.0001). Significant positive correlations were found between respondents' current performance levels on each of the research items and amount of research involvement, indicating good criterion validity in the areas tested. Factor analysis revealed seven factors with eigenvalues of > 1.0, KMO (Kaiser-Meyer-Olkin) measure of sampling adequacy = 0.680 and
Validation of the Regicor Short Physical Activity Questionnaire for the Adult Population

PubMed Central

Molina, Luis; Sarmiento, Manuel; Peñafiel, Judith; Donaire, David; Garcia-Aymerich, Judith; Gomez, Miquel; Ble, Mireia; Ruiz, Sonia; Frances, Albert; Schröder, Helmut; Marrugat, Jaume; Elosua, Roberto

2017-01-01

Objective To develop and validate a short questionnaire to estimate physical activity (PA) practice and sedentary behavior for the adult population. Methods The short questionnaire was developed using data from a cross-sectional population-based survey (n = 6352) that included the Minnesota leisure-time PA questionnaire. Activities that explained a significant proportion of the variability of population PA practice were identified. Validation of the short questionnaire included a cross-sectional component to assess validity with respect to the data collected by accelerometers and a longitudinal component to assess reliability and sensitivity to detect changes (n = 114, aged 35 to 74 years). Results Six types of activities that accounted for 87% of population variability in PA estimated with the Minnesota questionnaire were selected. The short questionnaire estimates energy expenditure in total PA and by intensity (light, moderate, vigorous), and includes 2 questions about sedentary behavior and a question about occupational PA. The short questionnaire showed high reliability, with intraclass correlation coefficients ranging between 0.79 to 0.95. The Spearman correlation coefficients between estimated energy expenditure obtained with the questionnaire and the number of steps detected by the accelerometer were as follows: 0.36 for total PA, 0.40 for moderate intensity, and 0.26 for vigorous intensity. The questionnaire was sensitive to detect changes in moderate and vigorous PA (correlation coefficients ranging from 0.26 to 0.34). Conclusion The REGICOR short questionnaire is reliable, valid, and sensitive to detect changes in moderate and vigorous PA. This questionnaire could be used in daily clinical practice and epidemiological studies. PMID:28085886
The Predictive Validity of Dynamic Assessment: A Review

ERIC Educational Resources Information Center

Caffrey, Erin; Fuchs, Douglas; Fuchs, Lynn S.

2008-01-01

The authors report on a mixed-methods review of 24 studies that explores the predictive validity of dynamic assessment (DA). For 15 of the studies, they conducted quantitative analyses using Pearson's correlation coefficients. They descriptively examined the remaining studies to determine if their results were consistent with findings from the…
Validation of an adapted arabic version of fibromyalgia syndrome impact questionnaire.

PubMed

El-Naby, Mai Abd; Hefny, Mohamed Ahmed; Fahim, Ayman Ekram; Awadalla, Magdy Ahmed

2013-10-01

Fibromyalgia (FM) is the most common chronic pain syndrome encountered in medical practice, affecting females more than males, and the estimated prevalence of FM in Egypt is 1.3 %. The aim was to translate and adapt the Fibromyalgia Impact Questionnaire (FIQ) into Arabic and assess reliability and validity. The Arabic version of Fibromyalgia Impact Questionnaire (FIQ-A) was adapted following the forward/backward translation approach. Fifty-one female patients with FM were studied to assess psychometric properties of the FIQ-A. Reliability was analyzed by the correlation coefficient between test and retest. Internal consistency was checked by the Cronbach's alpha coefficient. Construct validity was assessed comparing FIQ-A with Health Assessment Questionnaire (HAQ), Health Assessment Questionnaire of Fibromyalgia (FHAQ), The Medical Outcome Survey Short-Form-36 (SF-36), and the Total Visual Analog Scale (TVAS) for FM symptom, and feasibility was assessed by the time taken in completing the FIQ-A and the proportion of patients completed the questionnaire. Patients studied were 33.2 ± 9.8 years old. Translation was concordant. Adaptation affected 4 sub-items of physical function. Test-retest correlation coefficient was 0.89 for total FIQ-A and Cronbach's alpha was 0.76. Excellent to good statistically significant correlations (p < 0.05) were found between the FIQ-A items and HAQ, FHAQ, and SF-36. The FIQ-A is a reliable, valid for measuring health status and physical function in Arabic-speaking FM patients.
Adaptation and Assessment of Reliability and Validity of the Greek Version of the Ohkuma Questionnaire for Dysphagia Screening

PubMed Central

Papadopoulou, Soultana L.; Exarchakos, Georgios; Christodoulou, Dimitrios; Theodorou, Stavroula; Beris, Alexandre; Ploumis, Avraam

2016-01-01

Introduction The Ohkuma questionnaire is a validated screening tool originally used to detect dysphagia among patients hospitalized in Japanese nursing facilities. Objective The purpose of this study is to evaluate the reliability and validity of the adapted Greek version of the Ohkuma questionnaire. Methods Following the steps for cross-cultural adaptation, we delivered the validated Ohkuma questionnaire to 70 patients (53 men, 17 women) who were either suffering from dysphagia or not. All of them completed the questionnaire a second time within a month. For all of them, we performed a bedside and VFSS study of dysphagia and asked participants to undergo a second VFSS screening, with the exception of nine individuals. Statistical analysis included measurement of internal consistency with Cronbach's α coefficient, reliability with Cohen's Kappa, Pearson's correlation coefficient and construct validity with categorical components, and One-Way Anova test. Results According to Cronbach's α coefficient (0.976) for total score, there was high internal consistency for the Ohkuma Dysphagia questionnaire. Test-retest reliability (Cohen's Kappa) ranged from 0.586 to 1.00, exhibiting acceptable stability. We also estimated the Pearson's correlation coefficient for the test-retest total score, which reached high levels (0.952; p = 0.000). The One-Way Anova test in the two measurement times showed statistically significant correlation in both measurements (p = 0.02 and p = 0.016). Conclusion The adapted Greek version of the questionnaire is valid and reliable and can be used for the screening of dysphagia in the Greek-speaking patients. PMID:28050209
Adaptation and Assessment of Reliability and Validity of the Greek Version of the Ohkuma Questionnaire for Dysphagia Screening.

PubMed

Papadopoulou, Soultana L; Exarchakos, Georgios; Christodoulou, Dimitrios; Theodorou, Stavroula; Beris, Alexandre; Ploumis, Avraam

2017-01-01

Introduction The Ohkuma questionnaire is a validated screening tool originally used to detect dysphagia among patients hospitalized in Japanese nursing facilities. Objective The purpose of this study is to evaluate the reliability and validity of the adapted Greek version of the Ohkuma questionnaire. Methods Following the steps for cross-cultural adaptation, we delivered the validated Ohkuma questionnaire to 70 patients (53 men, 17 women) who were either suffering from dysphagia or not. All of them completed the questionnaire a second time within a month. For all of them, we performed a bedside and VFSS study of dysphagia and asked participants to undergo a second VFSS screening, with the exception of nine individuals. Statistical analysis included measurement of internal consistency with Cronbach's α coefficient, reliability with Cohen's Kappa, Pearson's correlation coefficient and construct validity with categorical components, and One-Way Anova test. Results According to Cronbach's α coefficient (0.976) for total score, there was high internal consistency for the Ohkuma Dysphagia questionnaire. Test-retest reliability (Cohen's Kappa) ranged from 0.586 to 1.00, exhibiting acceptable stability. We also estimated the Pearson's correlation coefficient for the test-retest total score, which reached high levels (0.952; p = 0.000). The One-Way Anova test in the two measurement times showed statistically significant correlation in both measurements ( p = 0.02 and p = 0.016). Conclusion The adapted Greek version of the questionnaire is valid and reliable and can be used for the screening of dysphagia in the Greek-speaking patients.
Validity evidence of non-technical skills assessment instruments in simulated anaesthesia crisis management.

PubMed

Jirativanont, T; Raksamani, K; Aroonpruksakul, N; Apidechakul, P; Suraseranivongse, S

2017-07-01

We sought to evaluate the validity of two non-technical skills evaluation instruments, the Anaesthetists' Non-Technical Skills (ANTS) behavioural marker system and the Ottawa Global Rating Scale (GRS), to apply them to anaesthesia training. The content validity, response process, internal structure, relations with other variables and consequences were described for validity evidence. Simulated crisis management sessions were initiated during which two trained raters evaluated the performance of postgraduate first-, second- and third-year (PGY-1, PGY-2 and PGY-3) anaesthesia residents. The study included 70 participants, composed of 24 PGY-1, 24 PGY-2 and 22 PGY-3 residents. Both instruments differentiated the non-technical skills of PGY-1 from PGY-3 residents ( P <0.05). Inter-rater agreement was measured using the intraclass correlation coefficient (ICC). For the ANTS instrument, the intraclass correlation coefficients for task management, team-working, situation awareness and decision-making were 0.79, 0.34, 0.81 and 0.70, respectively. For the Ottawa GRS, the intraclass correlation coefficients for overall performance, leadership, problem-solving, situation awareness, resource utilisation and communication skills were 0.86, 0.83, 0.84, 0.87, 0.80 and 0.86, respectively. The Cronbach's alpha for internal consistency of the ANTS instrument was 0.93, and was 0.96 for the Ottawa GRS. There was a high correlation between the ANTS and Ottawa GRS. The raters reported the ease of use of the Ottawa GRS compared to the ANTS. We found sufficient evidence of validity in the ANTS instrument and the Ottawa GRS for the evaluation of non-technical skills in a simulated anaesthesia setting, but the Ottawa GRS was more practical and had higher reliability.
Application of the Gini Correlation Coefficient to Infer Regulatory Relationships in Transcriptome Analysis[W][OA

PubMed Central

Ma, Chuang; Wang, Xiangfeng

2012-01-01

One of the computational challenges in plant systems biology is to accurately infer transcriptional regulation relationships based on correlation analyses of gene expression patterns. Despite several correlation methods that are applied in biology to analyze microarray data, concerns regarding the compatibility of these methods with the gene expression data profiled by high-throughput RNA transcriptome sequencing (RNA-Seq) technology have been raised. These concerns are mainly due to the fact that the distribution of read counts in RNA-Seq experiments is different from that of fluorescence intensities in microarray experiments. Therefore, a comprehensive evaluation of the existing correlation methods and, if necessary, introduction of novel methods into biology is appropriate. In this study, we compared four existing correlation methods used in microarray analysis and one novel method called the Gini correlation coefficient on previously published microarray-based and sequencing-based gene expression data in Arabidopsis (Arabidopsis thaliana) and maize (Zea mays). The comparisons were performed on more than 11,000 regulatory relationships in Arabidopsis, including 8,929 pairs of transcription factors and target genes. Our analyses pinpointed the strengths and weaknesses of each method and indicated that the Gini correlation can compensate for the shortcomings of the Pearson correlation, the Spearman correlation, the Kendall correlation, and the Tukey’s biweight correlation. The Gini correlation method, with the other four evaluated methods in this study, was implemented as an R package named rsgcc that can be utilized as an alternative option for biologists to perform clustering analyses of gene expression patterns or transcriptional network analyses. PMID:22797655
Reliability and validity of a Turkish version of the Global Pelvic Floor Bother Questionnaire.

PubMed

Doğan, Hanife; Özengin, Nuriye; Bakar, Yeşim; Duran, Bülent

2016-10-01

The aim of this study was to translate the Global Pelvic Floor Bother Questionnaire (GPFBQ) into Turkish and to assess its validity and reliability. The Turkish adaptation of the GPFBQ was created by following the stages of the intercultural adaptation process. A test-retest interval of 1 week was used to assess the reliability, which was examined by the intraclass correlation coefficient. The validity of the GPFBQ was assessed and compared with the Pelvic Floor Distress Inventory-20 (PFDI-20) and the Pelvic Floor Impact Questionnaire-7 (PFIQ-7) using Spearman's rank correlation coefficients. For construct validity, confirmatory factor analysis was performed. A total of 131 women, whose mean age was 46.83 years, were included in the study. The test-retest reliability of the GPFBQ was excellent (0.998, p < 0.0001). The GPFBQ correlated significantly with the PFDI-20 (r = 0.860, p = 0.00) and PFIQ-7 (r = 0.802, p = 0.00). Confirmatory factor analysis was performed to determine construct validity, and it was found that it had four dimensions. The Turkish version of the GPFBQ is a valid and reliable tool for assessing the symptoms of bother and severity in Turkish-speaking women with pelvic floor dysfunction.
Time-varying coefficient vector autoregressions model based on dynamic correlation with an application to crude oil and stock markets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Fengbin, E-mail: fblu@amss.ac.cn

This paper proposes a new time-varying coefficient vector autoregressions (VAR) model, in which the coefficient is a linear function of dynamic lagged correlation. The proposed model allows for flexibility in choices of dynamic correlation models (e.g. dynamic conditional correlation generalized autoregressive conditional heteroskedasticity (GARCH) models, Markov-switching GARCH models and multivariate stochastic volatility models), which indicates that it can describe many types of time-varying causal effects. Time-varying causal relations between West Texas Intermediate (WTI) crude oil and the US Standard and Poor’s 500 (S&P 500) stock markets are examined by the proposed model. The empirical results show that their causal relationsmore » evolve with time and display complex characters. Both positive and negative causal effects of the WTI on the S&P 500 in the subperiods have been found and confirmed by the traditional VAR models. Similar results have been obtained in the causal effects of S&P 500 on WTI. In addition, the proposed model outperforms the traditional VAR model.« less
Time-varying coefficient vector autoregressions model based on dynamic correlation with an application to crude oil and stock markets.

PubMed

Lu, Fengbin; Qiao, Han; Wang, Shouyang; Lai, Kin Keung; Li, Yuze

2017-01-01

This paper proposes a new time-varying coefficient vector autoregressions (VAR) model, in which the coefficient is a linear function of dynamic lagged correlation. The proposed model allows for flexibility in choices of dynamic correlation models (e.g. dynamic conditional correlation generalized autoregressive conditional heteroskedasticity (GARCH) models, Markov-switching GARCH models and multivariate stochastic volatility models), which indicates that it can describe many types of time-varying causal effects. Time-varying causal relations between West Texas Intermediate (WTI) crude oil and the US Standard and Poor's 500 (S&P 500) stock markets are examined by the proposed model. The empirical results show that their causal relations evolve with time and display complex characters. Both positive and negative causal effects of the WTI on the S&P 500 in the subperiods have been found and confirmed by the traditional VAR models. Similar results have been obtained in the causal effects of S&P 500 on WTI. In addition, the proposed model outperforms the traditional VAR model. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
A Bayesian Framework for Estimating the Concordance Correlation Coefficient Using Skew-elliptical Distributions.

PubMed

Feng, Dai; Baumgartner, Richard; Svetnik, Vladimir

2018-04-05

The concordance correlation coefficient (CCC) is a widely used scaled index in the study of agreement. In this article, we propose estimating the CCC by a unified Bayesian framework that can (1) accommodate symmetric or asymmetric and light- or heavy-tailed data; (2) select model from several candidates; and (3) address other issues frequently encountered in practice such as confounding covariates and missing data. The performance of the proposal was studied and demonstrated using simulated as well as real-life biomarker data from a clinical study of an insomnia drug. The implementation of the proposal is accessible through a package in the Comprehensive R Archive Network.
Correlation between tissue metabolism and cellularity assessed by standardized uptake value and apparent diffusion coefficient in peritoneal metastasis.

PubMed

Yu, Xue; Lee, Elaine Yuen Phin; Lai, Vincent; Chan, Queenie

2014-07-01

To evaluate the correlation between standardized uptake value (SUV) (tissue metabolism) and apparent diffusion coefficient (ADC) (water diffusivity) in peritoneal metastases. Patients with peritoneal dissemination detected on (18)F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) were prospectively recruited for MRI examinations with informed consent and the study was approved by the local Institutional Review Board. FDG-PET/CT, diffusion-weighted imaging (DWI), MRI, and DWI/MRI images were independently reviewed by two radiologists based on visual analysis. SUVmax/SUVmean and ADCmin/ADCmean were obtained manually by drawing ROIs over the peritoneal metastases on FDG-PET/CT and DWI, respectively. Diagnostic characteristics of each technique were evaluated. Pearson's coefficient and McNemar and Kappa tests were used for statistical analysis. Eight patients were recruited for this prospective study and 34 peritoneal metastases were evaluated. ADCmean was significantly and negatively correlated with SUVmax (r = -0.528, P = 0.001) and SUVmean (r = -0.548, P = 0.001). ADCmin had similar correlation with SUVmax (r = -0.508, P = 0.002) and SUVmean (r = -0.513, P = 0.002). DWI/MRI had high diagnostic performance (accuracy = 98%) comparable to FDG-PET/CT, in peritoneal metastasis detection. Kappa values were excellent for all techniques. There was a significant inverse correlation between SUV and ADC. © 2013 Wiley Periodicals, Inc.

Effects of soot absorption coefficient-Planck function correlation on radiative heat transfer in oxygen-enriched propane turbulent diffusion flame

NASA Astrophysics Data System (ADS)

Consalvi, J. L.; Nmira, F.

2016-03-01

The main objective of this article is to quantify the influence of the soot absorption coefficient-Planck function correlation on radiative loss and flame structure in an oxygen-enhanced propane turbulent diffusion flame. Calculations were run with and without accounting for this correlation by using a standard k-ε model and the steady laminar flamelet model (SLF) coupled to a joint Probability Density Function (PDF) of mixture fraction, enthalpy defect, scalar dissipation rate, and soot quantities. The PDF transport equation is solved by using a Stochastic Eulerian Field (SEF) method. The modeling of soot production is carried out by using a flamelet-based semi-empirical acetylene/benzene soot model. Radiative heat transfer is modeled by using a wide band correlated-k model and turbulent radiation interactions (TRI) are accounted for by using the Optically-Thin Fluctuation Approximation (OTFA). Predicted soot volume fraction, radiant wall heat flux distribution and radiant fraction are in good agreement with the available experimental data. Model results show that soot absorption coefficient and Planck function are negatively correlated in the region of intense soot emission. Neglecting this correlation is found to increase significantly the radiative loss leading to a substantial impact on flame structure in terms of mean and rms values of temperature. In addition mean and rms values of soot volume fraction are found to be less sensitive to the correlation than temperature since soot formation occurs mainly in a region where its influence is low.
Adaptation and validation of the Distress Scale for Mexican patients with type 2 diabetes and hypertension: a cross-sectional survey.

PubMed

Martinez-Vega, Ingrid Patricia; Doubova, Svetlana V; Aguirre-Hernandez, Rebeca; Infante-Castañeda, Claudia

2016-03-02

The aim of this study was to adapt and validate the Distress Scale for Mexican patients with type 2 diabetes and hypertension (DSDH17M). Two family medicine clinics affiliated with the Mexican Institute of Social Security. 722 patients with type 2 diabetes and/or hypertension (235 patients with diabetes, 233 patients with hypertension and 254 patients with both diseases). A cross-sectional survey. The validation procedures included: (1) content validity using a group of experts, (2) construct validity from exploratory factor analysis, (3) internal consistency using Cronbach's α, (4) convergent validity between DSDH17M and anxiety and depression using the Spearman correlation coefficient, (5) discriminative validity through the Wilcoxon rank-sum test and (6) test-retest reliability using intraclass correlation coefficient. The DSDH17M has 17 items and three factors explaining 67% of the total variance. Cronbach α ranged from 0.83 to 0.91 among factors. The first factor of 'Regime-related Distress and Emotional Burden' moderately correlated with anxiety and depression scores. Discriminative validity revealed that patients with obesity, those with stressful events and those who did not adhere to pharmacological treatment had significantly higher distress scores in all DSDH17M domains. Test-retest intraclass correlation coefficient for DSDH17M ranged from 0.92 to 0.97 among factors. DSDH17M is a valid and reliable tool to identify distress of patients with type 2 diabetes and hypertension. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Validation of the Slovenian version of Hospital Anxiety and Depression Scale in female cancer patients.

PubMed

Miklavcic, Ilonka Vucko; Snoj, Zvezdana; Mlakar, Janez; Pregelj, Peter

2008-06-01

The present study describes the translation process of the Hospital Anxiety and Depression Scale (HADS) into the Slovenian language and the testing of its reliability and validity on the psychological morbidity in female cancer patients. The English version of the HADS was translated into the Slovene language using the 'forward-backward' procedure. The questionnaire was used in a study of 202 female cancer patients together with a clinical structured interview (CSI) to measure psychological state. A biserial correlation coefficient was calculated. The value of biserial correlation coefficient was 0.81 for the depression scale and 0.91 for the anxiety scale. The validation process of the Slovenian HADS score version shows metric properties similar to those in international studies, suggesting that it measures the same constructs, in the same way, as the original HADS score form. This validation study of the Slovenian version of the HADS proved that it is an acceptable and valid measure of psychological distress among female cancer patients.
The coefficient of determination R2 and intra-class correlation coefficient from generalized linear mixed-effects models revisited and expanded.

PubMed

Nakagawa, Shinichi; Johnson, Paul C D; Schielzeth, Holger

2017-09-01

The coefficient of determination R 2 quantifies the proportion of variance explained by a statistical model and is an important summary statistic of biological interest. However, estimating R 2 for generalized linear mixed models (GLMMs) remains challenging. We have previously introduced a version of R 2 that we called [Formula: see text] for Poisson and binomial GLMMs, but not for other distributional families. Similarly, we earlier discussed how to estimate intra-class correlation coefficients (ICCs) using Poisson and binomial GLMMs. In this paper, we generalize our methods to all other non-Gaussian distributions, in particular to negative binomial and gamma distributions that are commonly used for modelling biological data. While expanding our approach, we highlight two useful concepts for biologists, Jensen's inequality and the delta method, both of which help us in understanding the properties of GLMMs. Jensen's inequality has important implications for biologically meaningful interpretation of GLMMs, whereas the delta method allows a general derivation of variance associated with non-Gaussian distributions. We also discuss some special considerations for binomial GLMMs with binary or proportion data. We illustrate the implementation of our extension by worked examples from the field of ecology and evolution in the R environment. However, our method can be used across disciplines and regardless of statistical environments. © 2017 The Author(s).
Reliability and validity of an adapted Arabic version of the Scoliosis Research Society-22r Questionnaire.

PubMed

Haidar, Rachid K; Kassak, Kassem; Masrouha, Karim; Ibrahim, Kamal; Mhaidli, Hani

2015-09-01

Cross-sectional validation and reliability assessment study of Arabic version of Scoliosis Research Society-22 (SRS-22r) Questionnaire. To develop and validate the Arabic version of the SRS-22r questionnaire. The diagnosis and treatment of adolescent idiopathic scoliosis may influence patient quality of life. SRS-22r is an internationally validated questionnaire used to assess function/activity, pain, self-image, and mental health of patients with scoliosis. It has been translated into several languages but not into Arabic language. Therefore, a valid health-related quality-of-life outcome questionnaire for patients with spinal deformity is still lacking in Arabic language. The English version of SRS-22r questionnaire was translated, back-translated, and culturally adapted to Arabic language. Then, 81 patients with idiopathic adolescent scoliosis were allocated randomly into either the reliability testing group (group 1) or the validity testing group (group 2). Group 1 patients completed Arabic version of SRS-22r questionnaire twice with 1-week interval in-between. Cronbach α and intraclass correlation coefficient were measured to determine internal consistency and temporal reliability. Group 2 patients completed the Arabic version of SRS-22r questionnaire and the previously validated Arabic version of 36-Item Short Form Health Survey (Short Form-36) questionnaire concurrently, and Pearson correlation coefficient was obtained to assess validity. Content analysis, internal consistency reliability, test/retest reproducibility (intraclass correlation coefficient range: 0.82-0.90), and test of concurrent validity showed satisfactory results. Function/activity and satisfaction with management domains had a lower Cronbach α (0.58 and 0.44, respectively, vs. 0.71-0.85 range for others). Self-image/appearance and satisfaction with management had a lower correlation with domains of the 36-Item Short Form Health Survey. An Arabic version of the SRS-22r questionnaire has
The validity and reliability of an iPhone app for measuring vertical jump performance.

PubMed

Balsalobre-Fernández, Carlos; Glaister, Mark; Lockey, Richard Anthony

2015-01-01

The purpose of this investigation was to analyse the concurrent validity and reliability of an iPhone app (called: My Jump) for measuring vertical jump performance. Twenty recreationally active healthy men (age: 22.1 ± 3.6 years) completed five maximal countermovement jumps, which were evaluated using a force platform (time in the air method) and a specially designed iPhone app. My jump was developed to calculate the jump height from flight time using the high-speed video recording facility on the iPhone 5 s. Jump heights of the 100 jumps measured, for both devices, were compared using the intraclass correlation coefficient, Pearson product moment correlation coefficient (r), Cronbach's alpha (α), coefficient of variation and Bland-Altman plots. There was almost perfect agreement between the force platform and My Jump for the countermovement jump height (intraclass correlation coefficient = 0.997, P < 0.001; Bland-Altman bias = 1.1 ± 0.5 cm, P < 0.001). In comparison with the force platform, My Jump showed good validity for the CMJ height (r = 0.995, P < 0.001). The results of the present study showed that CMJ height can be easily, accurately and reliably evaluated using a specially developed iPhone 5 s app.
Reliability and validity of the Chinese pediatric voice handicap index.

PubMed

Liu, Kena; Liu, Shaofeng; Zhou, Zhou; Ren, Qinyi; Zhong, Jie; Luo, Renzhong; Qin, Huabiao; Zhang, Siyi; Ge, Pingjiang

2018-02-01

To evaluate the reliability and validity of the Chinese version of pediatric voice handicap index (pVHI). The original English version-pVHI was translated into Chinese. Parents of 52 children with voice dysphonia and 43 children with no history or symptoms of voice problems were asked to fill the Chinese pVHI questionnaires twice with an interval of 2 weeks. GRB (Grade, Roughness, Breathiness) scale was used for perceptual assessment by two otolaryngologists and one speech pathologist for each child's voice. The internal consistency was assessed using Cronbach's alpha coefficient. Pearson's correlation coefficient was used to evaluate the test-retest reliability. The Kendall's coefficient of concordance W was used to assess the consistency of GRB scores of 3 voice specialists. The nonparametric Mann-Whitney test was used to assess the differences between the dysphonia group and controls. The correlation between pVHI and GRB scores were assessed using Pearson's correlation coefficient. The internal consistency of total score and three subscales scores of Chinese pVHI were 0.788-0.944. The test-retest reliability was 0.631-0.887(P < .001). The pVHI scores of control group significantly were lower than the pathological group (P = .000). The GRB scores of 3 voice specialists have an excellent consistency (W = 0.694-0.807, P = .000). The pVHI scores positively correlated with GRB assessment (P < .01). The Chinese version of pVHI had a good reliability and validity. It can be applicable and useful supplementary tool for evaluating parents' perception of their children's dysphonia. Copyright © 2017. Published by Elsevier B.V.
A Performance Comparison on the Probability Plot Correlation Coefficient Test using Several Plotting Positions for GEV Distribution.

NASA Astrophysics Data System (ADS)

Ahn, Hyunjun; Jung, Younghun; Om, Ju-Seong; Heo, Jun-Haeng

2014-05-01

It is very important to select the probability distribution in Statistical hydrology. Goodness of fit test is a statistical method that selects an appropriate probability model for a given data. The probability plot correlation coefficient (PPCC) test as one of the goodness of fit tests was originally developed for normal distribution. Since then, this test has been widely applied to other probability models. The PPCC test is known as one of the best goodness of fit test because it shows higher rejection powers among them. In this study, we focus on the PPCC tests for the GEV distribution which is widely used in the world. For the GEV model, several plotting position formulas are suggested. However, the PPCC statistics are derived only for the plotting position formulas (Goel and De, In-na and Nguyen, and Kim et al.) in which the skewness coefficient (or shape parameter) are included. And then the regression equations are derived as a function of the shape parameter and sample size for a given significance level. In addition, the rejection powers of these formulas are compared using Monte-Carlo simulation. Keywords: Goodness-of-fit test, Probability plot correlation coefficient test, Plotting position, Monte-Carlo Simulation ACKNOWLEDGEMENTS This research was supported by a grant 'Establishing Active Disaster Management System of Flood Control Structures by using 3D BIM Technique' [NEMA-12-NH-57] from the Natural Hazard Mitigation Research Group, National Emergency Management Agency of Korea.
Reliability and validity of the French-Canadian version of the scoliosis research society 22 questionnaire in France.

PubMed

Lonjon, Guillaume; Ilharreborde, Brice; Odent, Thierry; Moreau, Sébastien; Glorion, Christophe; Mazda, Keyvan

2014-01-01

Outcome study to determine the internal consistency, reproducibility, and concurrent validity of the French-Canadian version of the Scoliosis Research Society 22 (SRS-22 fcv) patient questionnaire in France. To determine whether the SRS-22 fcv can be used in a population from France. The SRS-22 has been translated and validated in multiple countries, notably in the French-Canadian language in Quebec, Canada. Use of SRS-22 fcv seems appropriate for evaluating adolescent idiopathic scoliosis in France. However, French-Canadian French is noticeably different from the French spoken in France, and no study has investigated the use of a French-Canadian version of a health-quality questionnaire in another French population. The methods used for validating the SRS-22 fcv in Quebec were adopted for use with a group of 200 adolescents with idiopathic scoliosis and 60 healthy adolescents in France. Reliability and reproducibility were measured by the Cronbach α and intraclass correlation coefficient (ICC), construct validity by factorial analysis, concurrent validity by the Short-Form of the survey, and discriminant validity by analysis of variance and multivariate linear regression. In France, the SRS-22 fcv showed good global internal consistency (Cronbach α = 0.87, intraclass correlation coefficient = 0.92), a coherent factorial structure, and high correlation coefficients between the SRS-22 fcv and Short-Form of the survey (P < 0.001). However, reliability and validity were slightly less than that for the instrument's original validation and the validation of the SRS-22 fcv in Quebec. These differences could be explained by language and cultural differences. The SRS-22 fcv is relevant for use in France, but further development and validation of a specific French questionnaire remain necessary to improve the assessment of functional outcomes of adolescents with scoliosis in France. N/A.
Statistical analysis of solid waste composition data: Arithmetic mean, standard deviation and correlation coefficients.

PubMed

Edjabou, Maklawe Essonanawe; Martín-Fernández, Josep Antoni; Scheutz, Charlotte; Astrup, Thomas Fruergaard

2017-11-01

Data for fractional solid waste composition provide relative magnitudes of individual waste fractions, the percentages of which always sum to 100, thereby connecting them intrinsically. Due to this sum constraint, waste composition data represent closed data, and their interpretation and analysis require statistical methods, other than classical statistics that are suitable only for non-constrained data such as absolute values. However, the closed characteristics of waste composition data are often ignored when analysed. The results of this study showed, for example, that unavoidable animal-derived food waste amounted to 2.21±3.12% with a confidence interval of (-4.03; 8.45), which highlights the problem of the biased negative proportions. A Pearson's correlation test, applied to waste fraction generation (kg mass), indicated a positive correlation between avoidable vegetable food waste and plastic packaging. However, correlation tests applied to waste fraction compositions (percentage values) showed a negative association in this regard, thus demonstrating that statistical analyses applied to compositional waste fraction data, without addressing the closed characteristics of these data, have the potential to generate spurious or misleading results. Therefore, ¨compositional data should be transformed adequately prior to any statistical analysis, such as computing mean, standard deviation and correlation coefficients. Copyright © 2017 Elsevier Ltd. All rights reserved.
Validity and reliability of the patient assessment of constipation quality of life questionnaire for the Turkish population.

PubMed

Bengi, Göksel; Yalçın, Mustafa; Akpınar, Hale; Keskinoğlu, Pembe; Ellidokuz, Hülya

2015-07-01

There are few specific evaluation forms for evaluating the quality of life among patients with chronic constipation. Our study aimed to determine the validity and reliability of the translated Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire for the Turkish population because evidence of its reliability and validity is required to justify its use in other studies and clinical practice. This study included 154 patients with constipation who were treated at the Department of Gastroenterology, Dokuz Eylül University Hospital between January and June 2012. The translated PAC-QOL questionnaire was completed by patients at the clinic and also at a 2-week follow-up to test its reliability. Cronbach's alpha coefficient (internal consistency) was 0.91 (good) for the translated PAC-QOL questionnaire. Time validity was evaluated using the intraclass correlation coefficient (ICC) method, and the ICC value for all questions was confirmed as 0.68 at the 2-week follow-up. The validity of the tool in the study group was evaluated using factor analysis, and the results were highly significant (Kaiser-Meyer-Olkin value: 0.857; Bartlett's test: p=0.001). Questions were categorized according to six factors based on the factor analysis, and these factors explained 65.1% of the total variation. For hypothesis verification of the tool, the correlation coefficient for PAC-QOL and PAC Symptoms (PAC-SYM) was r=0.577 (p<0.001), whereas the correlation coefficient for PAC-QOL and constipation severity score was r=0.457 (p<0.001). The PAC-QOL questionnaire was reliable, although not valid because of the limited sample group.
The Consumer Quality Index in an accident and emergency department: internal consistency, validity and discriminative capacity.

PubMed

Bos, Nanne; Sturms, Leontien M; Stellato, Rebecca K; Schrijvers, Augustinus J P; van Stel, Henk F

2015-10-01

Patients' experiences are an indicator of health-care performance in the accident and emergency department (A&E). The Consumer Quality Index for the Accident and Emergency department (CQI A&E), a questionnaire to assess the quality of care as experienced by patients, was investigated. The internal consistency, construct validity and discriminative capacity of the questionnaire were examined. In the Netherlands, twenty-one A&Es participated in a cross-sectional survey, covering 4883 patients. The questionnaire consisted of 78 questions. Principal components analysis determined underlying domains. Internal consistency was determined by Cronbach's alpha coefficients, construct validity by Pearson's correlation coefficients and the discriminative capacity by intraclass correlation coefficients and reliability of A&E-level mean scores (G-coefficient). Seven quality domains emerged from the principal components analysis: information before treatment, timeliness, attitude of health-care professionals, professionalism of received care, information during treatment, environment and facilities, and discharge management. Domains were internally consistent (range: 0.67-0.84). Five domains and the 'global quality rating' had the capacity to discriminate among A&Es (significant intraclass correlation coefficient). Four domains and the 'global quality rating' were close to or above the threshold for reliably demonstrating differences among A&Es. The patients' experiences score on the domain timeliness showed the largest range between the worst- and best-performing A&E. The CQI A&E is a validated survey to measure health-care performance in the A&E from patients' perspective. Five domains regarding quality of care aspects and the 'global quality rating' had the capacity to discriminate among A&Es. © 2013 John Wiley & Sons Ltd.
Common pediatric cerebellar tumors: correlation between cell densities and apparent diffusion coefficient metrics.

PubMed

Koral, Korgün; Mathis, Derek; Gimi, Barjor; Gargan, Lynn; Weprin, Bradley; Bowers, Daniel C; Margraf, Linda

2013-08-01

To test whether there is correlation between cell densities and apparent diffusion coefficient (ADC) metrics of common pediatric cerebellar tumors. This study was reviewed for issues of patient safety and confidentiality and was approved by the Institutional Review Board of the University of Texas Southwestern Medical Center and was compliant with HIPAA. The need for informed consent was waived. Ninety-five patients who had preoperative magnetic resonance imaging and surgical pathologic findings available between January 2003 and June 2011 were included. There were 37 pilocytic astrocytomas, 34 medulloblastomas (23 classic, eight desmoplastic-nodular, two large cell, one anaplastic), 17 ependymomas (13 World Health Organization [WHO] grade II, four WHO grade III), and seven atypical teratoid rhabdoid tumors. ADCs of solid tumor components and normal cerebellum were measured. Tumor-to-normal brain ADC ratios (hereafter, ADC ratio) were calculated. The medulloblastomas and ependymomas were subcategorized according to the latest WHO classification, and tumor cellularity was calculated. Correlation was sought between cell densities and mean tumor ADCs, minimum tumor ADCs, and ADC ratio. When all tumors were considered together, negative correlation was found between cellularity and mean tumor ADCs (ρ = -0.737, P < .05) and minimum tumor ADCs (ρ = -0.736, P < .05) of common pediatric cerebellar tumors. There was no correlation between cellularity and ADC ratio. Negative correlation was found between cellularity and minimum tumor ADC in atypical teratoid rhabdoid tumors (ρ = -0.786, P < .05). In atypical teratoid rhabdoid tumors, no correlation was found between cellularity and mean tumor ADC and ADC ratio. There was no correlation between the ADC metrics and cellularity of the pilocytic astrocytomas, medulloblastomas, and ependymomas. Negative correlation was found between cellularity and ADC metrics of common pediatric cerebellar tumors. Although ADC metrics are
Supportive care needs of Mexican adult cancer patients: validation of the Mexican version of the Short-Form Supportive Care Needs Questionnaire (SCNS-SFM).

PubMed

Doubova, Svetlana V; Aguirre-Hernandez, Rebeca; Gutiérrez-de la Barrera, Marcos; Infante-Castañeda, Claudia; Pérez-Cuevas, Ricardo

2015-09-01

The purpose of this study is to validate the Mexican version of the Short-Form Supportive Care Needs survey (SCNS-SFM). A cross-sectional survey was conducted from June to December 2013 at the Oncology Hospital of the Mexican Institute of Social Security in Mexico City. The study included 825 subsequent cancer patients >20 years of age with all forms of solid cancer. Patients had prior surgical removal of histologically confirmed cancer and attended outpatient consultations. Validation of SCNS-SFM included the following: (1) content validity through a group of experts; (2) construct validity through an exploratory factor analysis based on the polychoric correlation matrix; (3) internal consistency using Cronbach's alpha; (4) convergent validity between SCNS-SFM and quality of life, anxiety, and depression scales by calculating Pearson's correlation coefficient; (5) discriminative validity through analysis of MANOVAs; and (6) test-retest reliability using intraclass correlation coefficient calculations. SCNS-SFM has 33 items with five factors accounting for 59 % of total variance. Cronbach's alpha values ranged from 0.78 to 0.90 among factors. SCNS-SFM has good convergent validity compared with quality of life and depression and anxiety scales and good discriminative validity, revealing great information, psychological support, and physical daily living needs for women, patients <60 years, and high physical daily living needs for those with <1 year since cancer diagnosis, with advanced disease stages and current chemo- or radiotherapy. Intraclass correlation coefficient between SCNS-SFM measurements was 0.9. SCNS-SFM has acceptable psychometric properties and is suitable to evaluate supportive care needs of cancer patients.
Reproducibility and relative validity of food group intake in a food frequency questionnaire developed for Nepalese diet.

PubMed

Shrestha, Archana; Koju, Rajendra Prasad; Beresford, Shirley A A; Chan, Kwun Chuen Gary; Connell, Frederik A; Karmacharya, Biraj Man; Shrestha, Pramita; Fitzpatrick, Annette L

2017-08-01

We developed a food frequency questionnaire (FFQ) designed to measure the dietary practices of adult Nepalese. The present study examined the validity and reproducibility of the FFQ. To evaluate the reproducibility of the FFQ, 116 subjects completed two 115-item FFQ across a four-month interval. Six 24-h dietary recalls were collected (1 each month) to assess the validity of the FFQ. Seven major food groups and 23 subgroups were clustered from the FFQ based on macronutrient composition. Spearman correlation coefficients evaluating reproducibility for all food groups were greater than 0.5, with the exceptions of oil. The correlations varied from 0.41 (oil) to 0.81 (vegetables). All crude spearman coefficients for validity were greater than 0.5 except for dairy products, pizzas/pastas and sausage/burgers. The FFQ was found to be reliable and valid for ranking the intake of food groups for Nepalese dietary intake.
Reliability and validation of the Dutch Achilles tendon Total Rupture Score.

PubMed

Opdam, K T M; Zwiers, R; Wiegerinck, J I; Kleipool, A E B; Haverlag, R; Goslings, J C; van Dijk, C N

2018-03-01

Patient-reported outcome measures (PROMs) have become a cornerstone for the evaluation of the effectiveness of treatment. The Achilles tendon Total Rupture Score (ATRS) is a PROM for outcome and assessment of an Achilles tendon rupture. The aim of this study was to translate the ATRS to Dutch and evaluate its reliability and validity in the Dutch population. A forward-backward translation procedure was performed according to the guidelines of cross-cultural adaptation process. The Dutch ATRS was evaluated for reliability and validity in patients treated for a total Achilles tendon rupture from 1 January 2012 to 31 December 2014 in one teaching hospital and one academic hospital. Reliability was assessed by the intraclass correlation coefficients (ICC), Cronbach's alpha and minimal detectable change (MDC). We assessed construct validity by calculation of Spearman's rho correlation coefficient with domains of the Foot and Ankle Outcome Score (FAOS), Victorian Institute of Sports Assessment-Achilles questionnaire (VISA-A) and Numeric Rating Scale (NRS) for pain in rest and during running. The Dutch ATRS had a good test-retest reliability (ICC = 0.852) and a high internal consistency (Cronbach's alpha = 0.96). MDC was 30.2 at individual level and 3.5 at group level. Construct validity was supported by 75 % of the hypothesized correlations. The Dutch ATRS had a strong correlation with NRS for pain during running (r = -0.746) and all the five subscales of the Dutch FAOS (r = 0.724-0.867). There was a moderate correlation with the VISA-A-NL (r = 0.691) and NRS for pain in rest (r = -0.580). The Dutch ATRS shows an adequate reliability and validity and can be used in the Dutch population for measuring the outcome of treatment of a total Achilles tendon rupture and for research purposes. Diagnostic study, Level I.
Three phase heat and mass transfer model for unsaturated soil freezing process: Part 2 - model validation

NASA Astrophysics Data System (ADS)

Zhang, Yaning; Xu, Fei; Li, Bingxi; Kim, Yong-Song; Zhao, Wenke; Xie, Gongnan; Fu, Zhongbin

2018-04-01

This study aims to validate the three-phase heat and mass transfer model developed in the first part (Three phase heat and mass transfer model for unsaturated soil freezing process: Part 1 - model development). Experimental results from studies and experiments were used for the validation. The results showed that the correlation coefficients for the simulated and experimental water contents at different soil depths were between 0.83 and 0.92. The correlation coefficients for the simulated and experimental liquid water contents at different soil temperatures were between 0.95 and 0.99. With these high accuracies, the developed model can be well used to predict the water contents at different soil depths and temperatures.
Cross-cultural adaptation and validation of the Turkish version of the pain catastrophizing scale among patients with ankylosing spondylitis

PubMed Central

İlçin, Nursen; Gürpınar, Barış; Bayraktar, Deniz; Savcı, Sema; Çetin, Pınar; Sarı, İsmail; Akkoç, Nurullah

2016-01-01

[Purpose] This study describes the cultural adaptation, validation, and reliability of the Turkish version of the Pain Catastrophizing Scale in patients with ankylosing spondylitis. [Methods] The validity of the Turkish version of the Pain Catastrophizing Scale was assessed by evaluating data quality (missing data and floor and ceiling effects), principal components analysis, internal consistency (Cronbach’s alpha), and construct validity (Spearman’s rho). Reproducibility analyses included standard measurement error, minimum detectable change, limits of agreement, and intraclass correlation coefficients. [Results] Sixty-four adult patients with ankylosing spondylitis with a mean age of 42.2 years completed the study. Factor analysis revealed that all questionnaire items could be grouped into two factors. Excellent internal consistency was found, with a Chronbach’s alpha value of 0.95. Reliability analyses showed an intraclass correlation coefficient (95% confidence interval) of 0.96 for the total score. There was a low correlation coefficient between the Turkish version of the Pain Catastrophizing Scale and body mass index, pain levels at rest and during activity, health-related quality of life, and fear and avoidance behaviors. [Conclusion] The results of this study indicate that the Turkish version of the Pain Catastrophizing Scale is a valid and reliable clinical and research tool for patients with ankylosing spondylitis. PMID:26957778
[Validation of the Polish version of The Authentic Leadership Questionnaire for the of evaluation purpose of nursing management staff in national hospital wards].

PubMed

Sierpińska, Lidia

2013-09-01

The Authentic Leadership Questionnaire (ALQ) is a standardized research instrument for the evaluation of individual elements of leader's conduct which contribute to the authentic leadership. The application of this questionnaire in Polish conditions required to carry out the validation process. The aim of the study was to evaluate of validity and reliability of the Polish version of the American research instrument for the needs of evaluation of authenticity of leadership of the nursing management in Polish hospitals. The study covered 286 nurses (143 head nurses and 143 of their subordinates) employed in 45 hospitals in Poland. Theoretical validity of the instrument was evaluated using Fisher's transformation (r-Person correlation coefficient), while the criterion validity of the ALQ was evaluated using rho-Spearman correlation coefficient and the BOHIPSZO questionnaire. The reliability of the ALQ was assessed by means of the Cronbach-alpha coefficient. The ALQ questionnaire applied for the evaluation of authenticity of leadership of the nursing management in Polish hospital wards shows an acceptable theoretical and criterion validity and reliability (Cronbach-alpha coefficient 0.80). The Polish version of the ALQ is valid and reliable, and may be applied in studies concerning the evaluation of authenticity of leadership of the nursing management in Polish hospital wards.
Comparing the Pearson and Spearman correlation coefficients across distributions and sample sizes: A tutorial using simulations and empirical data.

PubMed

de Winter, Joost C F; Gosling, Samuel D; Potter, Jeff

2016-09-01

The Pearson product–moment correlation coefficient ( r p ) and the Spearman rank correlation coefficient ( r s ) are widely used in psychological research. We compare r p and r s on 3 criteria: variability, bias with respect to the population value, and robustness to an outlier. Using simulations across low (N = 5) to high (N = 1,000) sample sizes we show that, for normally distributed variables, r p and r s have similar expected values but r s is more variable, especially when the correlation is strong. However, when the variables have high kurtosis, r p is more variable than r s . Next, we conducted a sampling study of a psychometric dataset featuring symmetrically distributed data with light tails, and of 2 Likert-type survey datasets, 1 with light-tailed and the other with heavy-tailed distributions. Consistent with the simulations, r p had lower variability than r s in the psychometric dataset. In the survey datasets with heavy-tailed variables in particular, r s had lower variability than r p , and often corresponded more accurately to the population Pearson correlation coefficient ( R p ) than r p did. The simulations and the sampling studies showed that variability in terms of standard deviations can be reduced by about 20% by choosing r s instead of r p . In comparison, increasing the sample size by a factor of 2 results in a 41% reduction of the standard deviations of r s and r p . In conclusion, r p is suitable for light-tailed distributions, whereas r s is preferable when variables feature heavy-tailed distributions or when outliers are present, as is often the case in psychological research. PsycINFO Database Record (c) 2016 APA, all rights reserved

Validation of an instrument to measure quality of life in British children with inflammatory bowel disease.

PubMed

Ogden, C A; Akobeng, A K; Abbott, J; Aggett, P; Sood, M R; Thomas, A G

2011-09-01

To validate IMPACT-III (UK), a health-related quality of life (HRQoL) instrument, in British children with inflammatory bowel disease (IBD). One hundred six children and parents were invited to participate. IMPACT-III (UK) was validated by inspection by health professionals and children to assess face and content validity, factor analysis to determine optimum domain structure, use of Cronbach alpha coefficients to test internal reliability, ANOVA to assess discriminant validity, correlation with the Child Health Questionnaire to assess concurrent validity, and use of intraclass correlation coefficients to assess test-retest reliability. The independent samples t test was used to measure differences between sexes and age groups, and between paper and computerised versions of IMPACT-III (UK). IMPACT-III (UK) had good face and content validity. The most robust factor solution was a 5-domain structure: body image, embarrassment, energy, IBD symptoms, and worries/concerns about IBD, all of which demonstrated good internal reliability (α = 0.74-0.88). Discriminant validity was demonstrated by significant (P < 0.05, P < 0.01) differences in HRQoL scores between the severe, moderate, and inactive/mild symptom severity groups for the embarrassment scale (63.7 vs 81.0 vs 81.2), IBD symptom scale (45.0 vs 64.2 vs 80.6), and the energy scale (46.4 vs 62.1 vs 77.7). Concurrent validity of IMPACT-III (UK) with comparable domains of the Child Health Questionnaire was confirmed. Test-retest reliability was confirmed with good intraclass correlation coefficients of 0.66 to 0.84. Paper and computer versions of IMPACT-III (UK) collected comparable scores, and there were no differences between the sexes and age groups. IMPACT-III (UK) appears to be a useful tool to measure HRQoL in British children with IBD.
Preliminary appraisal of the reliability and validity of the Colorado State University Feline Acute Pain Scale.

PubMed

Shipley, Hilary; Guedes, Alonso; Graham, Lynelle; Goudie-DeAngelis, Elizabeth; Wendt-Hornickle, Erin

2018-05-01

Objectives The objective of this study was to determine the inter-rater reliability and convergent validity of the Colorado State University Feline Acute Pain Scale (CSU-FAPS) in a preliminary appraisal of its performance in a clinical teaching setting. Methods Sixty-eight female cats were assessed for pain after ovariohysterectomy. A cohort of 21 cats was examined independently by four raters (two board-certified anesthesiologists and two anesthesia residents) with the CSU-FAPS, and intra-class correlation coefficient (ICC) was used to determine inter-rater reliability. Weighted Cohen's kappa was used to determine inter-rater reliability centered on the 'need to reassess analgesic plan' (dichotomous scale). A separate cohort of 47 cats was evaluated independently by two raters (one board-certified anesthesiologist and one veterinary small animal rotating intern) using the CSU-FAPS and the Glasgow Composite Measure Pain Scale (CMPS-Feline), and Spearman rank-order correlation was determined to assess convergent validity. Reliability was interpreted using Altman's classification as very good, good, moderate, fair and poor. Validity was considered adequate if correlation coefficients were between 0.4 and 0.8. Results The ICC was 0.61 for anesthesiologists and 0.67 for residents, indicating good reliability. Weighted Cohen's kappa was 0.79 for anesthesiologists and 0.44 for residents, indicating moderate to good reliability. The Spearman rank correlation indicated a statistically significant ( P = 0.0003) positive correlation (0.31; 95% confidence interval 0.14-0.46) between the CSU-FAPS and the CMPS-Feline. Conclusions and relevance The CSU-FAPS showed moderate-to-good inter-rater reliability when used by veterinarians to assess pain level or need to reassess analgesic plan after ovariohysterectomy in cats. The validity fell short of current guidelines for correlation coefficients and further refinement and testing are warranted to improve its performance.
Validity of a food frequency questionnaire to assess food intake in Mexican adolescent and adult population.

PubMed

Denova-Gutiérrez, Edgar; Ramírez-Silva, Ivonne; Rodríguez-Ramírez, Sonia; Jiménez-Aguilar, Alejandra; Shamah-Levy, Teresa; Rivera-Dommarco, Juan A

2016-01-01

To assess the validity of a 140-item semiquantitative food frequency questionnaire (SFFQ), in Mexican adolescents and adults. Dietary intakes using a SFFQ and two 24-hour dietary recalls (24DRs), in nonconsecutive days during the same week were measured from 178 adolescents and 230 adults participating in the Mexican National Health and Nutrition Survey-2012.Validity was evaluated using correlation coefficients (CC),deattenuated CC, linear regression models, cross-classification analysis, and the Bland-Altman method. In adults, deattenuated correlation coefficients between the SFFQ and the 24DRs ranged from 0.30 for folate to 0.61 for saturated fat. In addition, 63% adults and 62% adolescents were classified in the same and adjacent quartile of nutrient intake when comparing data from SFFQ and 24DRs. The SFFQ had moderate validity for energy, macronutrients and micronutrients. It also had good validity to rank individuals according to their dietary intake of different nutrients.
Validity and Reliability of the Turkish version of DSM-5 Social Anxiety Disorder Severity Scale- Child Form.

PubMed

Yalin Sapmaz, Şermin; Ergin, Dilek; Şen Celasin, Nesrin; Karaarslan, Duygu; Öztürk, Masum; Özek Erkuran, Handan; Köroğlu, Ertuğrul; Aydemir, Ömer

2017-12-01

This study aimed to assess the validity and reliability of the Turkish version of the Diagnostic and statistical manual of Mental Disorders. (5 th ed.) (DSM-5) Social Anxiety Disorder Severity Scale- Child Form. The scale was prepared by carrying out the translation and back translation of the DSM-5 Social Anxiety Disorder Severity Scale - Child Form. The study group consisted of 31 patients that had been treated in a child psychiatry unit and diagnosed with social anxiety disorder and 99 healthy volunteers that were attending middle or high school during the study period. For the assessment, the Screen for Child Anxiety and Related Emotional Disorders (SCARED) was also used along with the DSM-5 Social Anxiety Disorder Severity Scale - Child Form. Regarding reliability analyses, Cronbach's alpha internal consistency coefficient was calculated as 0.941, while item-total score correlation coefficients were measured between 0.566 and 0.866. A test-retest correlation coefficient was calculated as r=0.711. As for construct validity, one factor that could explain 66.0 % of the variance was obtained. As for concurrent validity, the scale showed a high correlation with the SCARED. It was concluded that the Turkish version of the DSM-5 Social Anxiety Disorder Severity Scale - Child Form could be utilized as a valid and reliable tool both in clinical practice and for research purposes.
Validity and reliability of the Japanese version of the FIM + FAM in patients with cerebrovascular accident.

PubMed

Miki, Emi; Yamane, Shingo; Yamaoka, Mai; Fujii, Hiroe; Ueno, Hiroka; Kawahara, Toshie; Tanaka, Keiko; Tamashiro, Hiroaki; Inoue, Eiji; Okamoto, Takatsugu; Kuriyama, Masaru

2016-09-01

The study aim was to investigate the validity and reliability of the Functional Independence Measure and Functional Assessment Measure (FIM + FAM), which is unfamiliar in Japan, by using its Japanese version (FIM + FAM-j) in patients with cerebrovascular accident (CVA). Forty-two CVA patients participated. Criterion validity was examined by correlating the full scale and subscales of FIM + FAM-j with several well-established measurements using Spearman's correlation coefficient. Reliability was evaluated by internal consistency (tested by Cronbach's alpha coefficient) and intra-rater reliability (tested by Kendall's tau correlation coefficient). Good-to-excellent criterion validity was found between the full scale and motor subscales of the FIM + FAM-j and the Barthel Index, National Institutes of Health Stroke Scale, modified Rankin Scale, and lower extremity Brunnstrom Recovery Stage. High internal consistency was observed within the full-scale FIM + FAM-j and the motor and cognitive subscales (Cronbach's alphas were 0.968, 0.954, and 0.948, respectively). Additionally, good intra-rater reliability was observed within the full scale and motor subscales, and excellent reliability for the cognitive subscales (taus were 0.83, 0.80, and 0.98, respectively). This study showed that the FIM + FAM-j demonstrated acceptable levels of validity and reliability when used for CVA as a measure of disability.
The validity of the 4-Skills Scan: A double validation study.

PubMed

van Kernebeek, W G; de Kroon, M L A; Savelsbergh, G J P; Toussaint, H M

2018-06-01

Adequate gross motor skills are an essential aspect of a child's healthy development. Where physical education (PE) is part of the primary school curriculum, a strong curriculum-based emphasis on evaluation and support of motor skill development in PE is apparent. Monitoring motor development is then a task for the PE teacher. In order to fulfil this task, teachers need adequate tools. The 4-Skills Scan is a quick and easily manageable gross motor skill instrument; however, its validity has never been assessed. Therefore, the purpose of this study is to assess the construct and concurrent validity of both 4-Skills Scans (version 2007 and version 2015). A total of 212 primary school children (6 - 12 years old), was requested to participate in both versions of the 4-Skills Scan. For assessing construct validity, children covered an obstacle course with video recordings for observation by an expert panel. For concurrent validity, a comparison was made with the MABC-2, by calculating Pearson correlations. Multivariable linear regression analyses were performed to determine the contribution of each subscale to the construct of gross motor skills, according to the MABC-2 and the expert panel. Correlations between the 4-Skills Scans and expert valuations were moderate, with coefficients of .47 (version 2007) and .46 (version 2015). Correlations between the 4-Skills Scans and the MABC-2 (gross) were moderate (.56) for version 2007 and high (.64) for version 2015. It is concluded that both versions of the 4-Skills Scans are satisfactory valid instruments for assessing gross motor skills during PE lessons. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Is EQ-5D a valid quality of life instrument in patients with Parkinson's disease? A study in Singapore.

PubMed

Luo, Nan; Low, Serena; Lau, Puay-Ngoh; Au, Wing-Lok; Tan, Louis C S

2009-06-01

The purpose of the present study was to evaluate the validity of the EQ-5D in patients with Parkinson's disease (PD) in Singapore. In a cross-sectional survey, patients with PD completed English or Chinese version of the EQ-5D, the 8-item Parkinson's disease questionnaire (PDQ-8), and questions assessing socio-demographic and health characteristics. Clinical data were retrieved from patients' medical records. The validity of the EQ-5D was assessed by testing a-priori hypotheses relating the EQ-5D to the PDQ-8 and clinical data. Two hundred and eight PD patients (English speaking: 135) participated in the study. Spearman correlation coefficients between the EQ-5D and PDQ-8 ranged from 0.25 to 0.75 for English-speaking patients and from 0.16 to 0.67 for Chinese-speaking patients. By and large, the EQ-5D scores were weakly or moderately correlated with Hoehn and Yahr stage (correlation coefficients: 0.05 to 0.43), Schwab and England Activities of Daily Living score (correlation coefficients: 0.10 to 0.60), and duration of PD (correlation coefficients: 0.16 to 0.43). The EQ-5D index scores for patients with dyskinesia or "wearing off" periods were significantly lower than those without these problems. The EQ-5D Visual Analog Scale (EQ-VAS) scores also differed for English-speaking patients with deferring dyskinesia, "wearing off" periods, or health transition status; however, such differences were not observed in patients who completed the survey in Chinese. The EQ-5D questionnaire appears valid for measuring quality of life in patients with PD in Singapore. However, the validity of EQ-VAS in Chinese-speaking patients with PD should be further assessed.
Reliable and valid assessment of point-of-care ultrasonography.

PubMed

Todsen, Tobias; Tolsgaard, Martin Grønnebæk; Olsen, Beth Härstedt; Henriksen, Birthe Merete; Hillingsø, Jens Georg; Konge, Lars; Jensen, Morten Lind; Ringsted, Charlotte

2015-02-01

To explore the reliability and validity of the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale for point-of-care ultrasonography (POC US) performance. POC US is increasingly used by clinicians and is an essential part of the management of acute surgical conditions. However, the quality of performance is highly operator-dependent. Therefore, reliable and valid assessment of trainees' ultrasonography competence is needed to ensure patient safety. Twenty-four physicians, representing novices, intermediates, and experts in POC US, scanned 4 different surgical patient cases in a controlled set-up. All ultrasound examinations were video-recorded and assessed by 2 blinded radiologists using OSAUS. Reliability was examined using generalizability theory. Construct validity was examined by comparing performance scores between the groups and by correlating physicians' OSAUS scores with diagnostic accuracy. The generalizability coefficient was high (0.81) and a D-study demonstrated that 1 assessor and 5 cases would result in similar reliability. The construct validity of the OSAUS scale was supported by a significant difference in the mean scores between the novice group (17.0; SD 8.4) and the intermediate group (30.0; SD 10.1), P = 0.007, as well as between the intermediate group and the expert group (72.9; SD 4.4), P = 0.04, and by a high correlation between OSAUS scores and diagnostic accuracy (Spearman ρ correlation coefficient = 0.76; P < 0.001). This study demonstrates high reliability as well as evidence of construct validity of the OSAUS scale for assessment of POC US competence. Hence, the OSAUS scale may be suitable for both in-training as well as end-of-training assessment.
Evaluating trauma team performance in a Level I trauma center: Validation of the trauma team communication assessment (TTCA-24).

PubMed

DeMoor, Stephanie; Abdel-Rehim, Shady; Olmsted, Richard; Myers, John G; Parker-Raley, Jessica

2017-07-01

Nontechnical skills (NTS), such as team communication, are well-recognized determinants of trauma team performance and good patient care. Measuring these competencies during trauma resuscitations is essential, yet few valid and reliable tools are available. We aimed to demonstrate that the Trauma Team Communication Assessment (TTCA-24) is a valid and reliable instrument that measures communication effectiveness during activations. Two tools with adequate psychometric strength (Trauma Nontechnical Skills Scale [T-NOTECHS], Team Emergency Assessment Measure [TEAM]) were identified during a systematic review of medical literature and compared with TTCA-24. Three coders used each tool to evaluate 35 stable and 35 unstable patient activations (defined according to Advanced Trauma Life Support criteria). Interrater reliability was calculated between coders using the intraclass correlation coefficient. Spearman rank correlation coefficient was used to establish concurrent validity between TTCA-24 and the other two validated tools. Coders achieved an intraclass correlation coefficient of 0.87 for stable patient activations and 0.78 for unstable activations scoring excellent on the interrater agreement guidelines. The median score for each assessment showed good team communication for all 70 videos (TEAM, 39.8 of 54; T-NOTECHS, 17.4 of 25; and TTCA-24, 87.4 of 96). A significant correlation between TTTC-24 and T-NOTECHS was revealed (p = 0.029), but no significant correlation between TTCA-24 and TEAM (p = 0.77). Team communication was rated slightly better across all assessments for stable versus unstable patient activations, but not statistically significant. TTCA-24 correlated with T-NOTECHS, an instrument measuring nontechnical skills for trauma teams, but not TEAM, a tool that assesses communication in generic emergency settings. TTCA-24 is a reliable and valid assessment that can be a useful adjunct when evaluating interpersonal and team communication during trauma
Cross-cultural adaptation and validation of the Patient-Rated Tennis Elbow Evaluation Questionnaire on lateral elbow tendinopathy for French-speaking patients.

PubMed

Kaux, Jean-François; Delvaux, François; Schaus, Jean; Demoulin, Christophe; Locquet, Médéa; Buckinx, Fanny; Beaudart, Charlotte; Dardenne, Nadia; Van Beveren, Julien; Croisier, Jean-Louis; Forthomme, Bénédicte; Bruyère, Olivier

Translation and validation of algo-functional questionnaire. The lateral elbow tendinopathy is a common injury in tennis players and physical workers. The Patient-Rated Tennis Elbow Evaluation (PRTEE) Questionnaire was specifically designed to measure pain and functional limitations in patients with lateral epicondylitis (tennis elbow). First developed in English, this questionnaire has since been translated into several languages. The aims of the study were to translate and cross-culturally adapt the PRTEE questionnaire into French and to evaluate the reliability and validity of this translated version of the questionnaire (PRTEE-F). The PRTEE was translated and cross-culturally adapted into French according to international guidelines. To assess the reliability and validity of the PRTEE-F, 115 participants were asked twice to fill in the PRTEE-F, and once the Disabilities of Arm, Shoulder and Hand Questionnaire (DASH) and the Short Form Health Survey (SF-36). Internal consistency (using Cronbach's alpha), test-retest reliability (using intraclass correlation coefficient (ICC), standard error of measurement and minimal detectable change), and convergent and divergent validity (using the Spearman's correlation coefficients respectively with the DASH and with some subscales of the SF-36) were assessed. The PRTEE was translated into French without any problems. PRTEE-F showed a good test-retest reliability for the overall score (ICC 0.86) and for each item (ICC 0.8-0.96) and a high internal consistency (Cronbach's alpha = 0.98). The correlation analyses revealed high correlation coefficients between PRTEE-F and DASH (convergent validity) and, as expected, a low or moderate correlation with the divergent subscales of the SF-36 (discriminant validity). There was no floor or ceiling effect. The PRTEE questionnaire was successfully cross-culturally adapted into French. The PRTEE-F is reliable and valid for evaluating French-speaking patients with lateral elbow
The Trojan Lifetime Champions Health Survey: development, validity, and reliability.

PubMed

Sorenson, Shawn C; Romano, Russell; Scholefield, Robin M; Schroeder, E Todd; Azen, Stanley P; Salem, George J

2015-04-01

Self-report questionnaires are an important method of evaluating lifespan health, exercise, and health-related quality of life (HRQL) outcomes among elite, competitive athletes. Few instruments, however, have undergone formal characterization of their psychometric properties within this population. To evaluate the validity and reliability of a novel health and exercise questionnaire, the Trojan Lifetime Champions (TLC) Health Survey. Descriptive laboratory study. A large National Collegiate Athletic Association Division I university. A total of 63 university alumni (age range, 24 to 84 years), including former varsity collegiate athletes and a control group of nonathletes. Participants completed the TLC Health Survey twice at a mean interval of 23 days with randomization to the paper or electronic version of the instrument. Content validity, feasibility of administration, test-retest reliability, parallel-form reliability between paper and electronic forms, and estimates of systematic and typical error versus differences of clinical interest were assessed across a broad range of health, exercise, and HRQL measures. Correlation coefficients, including intraclass correlation coefficients (ICCs) for continuous variables and κ agreement statistics for ordinal variables, for test-retest reliability averaged 0.86, 0.90, 0.80, and 0.74 for HRQL, lifetime health, recent health, and exercise variables, respectively. Correlation coefficients, again ICCs and κ, for parallel-form reliability (ie, equivalence) between paper and electronic versions averaged 0.90, 0.85, 0.85, and 0.81 for HRQL, lifetime health, recent health, and exercise variables, respectively. Typical measurement error was less than the a priori thresholds of clinical interest, and we found minimal evidence of systematic test-retest error. We found strong evidence of content validity, convergent construct validity with the Short-Form 12 Version 2 HRQL instrument, and feasibility of administration in an elite
Palliative sedation: reliability and validity of sedation scales.

PubMed

Arevalo, Jimmy J; Brinkkemper, Tijn; van der Heide, Agnes; Rietjens, Judith A; Ribbe, Miel; Deliens, Luc; Loer, Stephan A; Zuurmond, Wouter W A; Perez, Roberto S G M

2012-11-01

Observer-based sedation scales have been used to provide a measurable estimate of the comfort of nonalert patients in palliative sedation. However, their usefulness and appropriateness in this setting has not been demonstrated. To study the reliability and validity of observer-based sedation scales in palliative sedation. A prospective evaluation of 54 patients under intermittent or continuous sedation with four sedation scales was performed by 52 nurses. Included scales were the Minnesota Sedation Assessment Tool (MSAT), Richmond Agitation-Sedation Scale (RASS), Vancouver Interaction and Calmness Scale (VICS), and a sedation score proposed in the Guideline for Palliative Sedation of the Royal Dutch Medical Association (KNMG). Inter-rater reliability was tested with the intraclass correlation coefficient (ICC) and Cohen's kappa coefficient. Correlations between the scales using Spearman's rho tested concurrent validity. We also examined construct, discriminative, and evaluative validity. In addition, nurses completed a user-friendliness survey. Overall moderate to high inter-rater reliability was found for the VICS interaction subscale (ICC = 0.85), RASS (ICC = 0.73), and KNMG (ICC = 0.71). The largest correlation between scales was found for the RASS and KNMG (rho = 0.836). All scales showed discriminative and evaluative validity, except for the MSAT motor subscale and VICS calmness subscale. Finally, the RASS was less time consuming, clearer, and easier to use than the MSAT and VICS. The RASS and KNMG scales stand as the most reliable and valid among the evaluated scales. In addition, the RASS was less time consuming, clearer, and easier to use than the MSAT and VICS. Further research is needed to evaluate the impact of the scales on better symptom control and patient comfort. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.
Creation and Validation of the Self-esteem/Self-image Female Sexuality (SESIFS) Questionnaire.

PubMed

Lordello, Maria Co; Ambrogini, Carolina C; Fanganiello, Ana L; Embiruçu, Teresa R; Zaneti, Marina M; Veloso, Laise; Piccirillo, Livia B; Crude, Bianca L; Haidar, Mauro; Silva, Ivaldo

2014-01-01

Self-esteem and self-image are psychological aspects that affect sexual function. To validate a new measurement tool that correlates the concepts of self-esteem, self-image, and sexuality. A 20-question test (the self-esteem/self-image female sexuality [SESIFS] questionnaire) was created and tested on 208 women. Participants answered: Rosenberg's self-esteem scale, the female sexual quotient (FSQ), and the SESIFS questionnaire. Pearson's correlation coefficient was used to test concurrent validity of the SESIFS against Rosenberg's self-esteem scale and the FSQ. Reliability was tested using the Cronbach's alpha coefficient. The new questionnaire had a good overall reliability (Cronbach's alpha r = 0.862, p < 0.001), but the sexual domain scored lower than expected (r = 0.65). The validity was good: overall score r = 0.38, p < 0.001, self-esteem domain r = 0.32, p < 0.001, self-image domain r = 0.31, p < 0.001, sexual domain r = 0.29, p < 0.001. The SESIFS questionnaire has limitations in measuring the correlation among self-esteem, self-image, and sexuality domains. A new, revised version is being tested and will be presented in an upcoming publication.
Heritabilities and genetic correlations of economic traits in Iranian native fowl and estimated genetic trend and inbreeding coefficients.

PubMed

Kamali, M A; Ghorbani, S H; Sharbabak, M Moradi; Zamiri, M J

2007-08-01

1. Genetic parameters were estimated in a base population of a closed experimental strain of fowl. Data were obtained on 21 245 Iranian native hens (breeding centre for Fars province) subject to 8 successive generations of selection. This population had been selected for body weight at 12 weeks of age (BW12) and egg number during the first 12 weeks of the laying period (EN), mean egg weight (EW) at weeks 28, 30 and 32, and age at sexual maturity (ASM). 2. The method of multi-traits restricted maximum likelihood with an animal model was used to estimate genetic parameters. Resulting heritabilities for BW12, EN, EW and ASM were 0.68 +/- 0.02, 0.40 +/- 0.02, 0.64 +/- 0.02 and 0.49 +/- 0.02, respectively. 3. Genetic correlations between BW12 and EN, EW and ASM were 0.11 +/- 0.33, 0.54 +/- 0.21 and -0.12 +/- 0.03, respectively. Genetic correlations between EN and EW and ASM were -0.09 +/- 0.03 and -0.85 +/- 0.01, respectively, while between EW and ASM, it was 0.05 +/- 0.03. 4. The overall predicted genetic gains, after 7 generations of selection, estimated by the regression coefficients of the breeding value on generation number were equal to 22.7, 0.17, 0.04 and -1.38, for BW12, EN, EW and ASM, respectively. 5. A pedigree file of 21 245 female and male birds was used to calculate inbreeding coefficients and their influence on production and reproduction traits. Average inbreeding coefficients for all birds, inbred birds, female birds and male birds were 0.048, 0.673, 0.055 and 0.047%, respectively. Regression coefficients of BW12, ASM, EN and EW on inbreeding coefficient for all birds were equal to 0.51 +/- 0.001, 0.31 +/- 0.003, -0.51 +/- 0.003 and 0.03 +/- 0.001, respectively.
Validation of a Persian version of the Fibromyalgia Impact Questionnaire (FIQ-P).

PubMed

Bidari, Ali; Hassanzadeh, Morteza; Mohabat, Mohamad-Farzam; Talachian, Elham; Khoei, Effat Merghati

2014-02-01

The aim of this study is to translate, adapt, and validate a Persian version of the Fibromyalgia (FM) Impact Questionnaire (FIQ-P). The FIQ-P was adapted following the translation and back-translation approach; then, it was administered to thirty females with FM. Participants also completed two other validated questionnaires, the Medical Outcome Survey Short Form-36 (SF-36) and the Beck Depression Inventory (BDI). Internal consistency within the FIQ-P items and its test-retest reliability were assessed with Cronbach's alpha and Spearman's correlation coefficient, respectively. Construct validity was analyzed by Spearman's r when correlating the FIQ-P to other questionnaires. The translated version was concordant. Adaptation affected two sub-items of physical function. Participants' mean age ± standard deviation was 40.4 ± 9.0 years. Internal consistency proved good with α = 0.80. Test-retest coefficient ranged from 0.50 for the item "work days missed" to 0.79 for all FIQ-P items. Fair and statistically significant (P < 0.01) correlations were found between the FIQ-P items and two other questionnaires, SF-36 (r = -0.57) and BDI (r = 0.53). We concluded that the FIQ-P is a valid and reliable instrument for measuring health status of Persian-speaking FM patients.
Reliability and Validity of a Chinese-Translated Version of a Pregnancy Physical Activity Questionnaire.

PubMed

Xiang, Mi; Konishi, Massayuki; Hu, Huanhuan; Takahashi, Masaki; Fan, Wenbi; Nishimaki, Mio; Ando, Karina; Kim, Hyeon-Ki; Tabata, Hiroki; Arao, Takashi; Sakamoto, Shizuo

2016-09-01

Objectives The objectives of the present study were to translate the English version of the Pregnancy Physical Activity Questionnaire into Chinese (PPAQ-C) and to determine its reliability and validity for use by pregnant Chinese women. Methods The study included 224 pregnant women during their first, second, or third trimesters of pregnancy who completed the PPAQ-C on their first visit and wore a uniaxial accelerometer (Lifecorder; Suzuken Co. Ltd) for 7 days. One week after the first visit, we collected the data from the uniaxial accelerometer records, and the women were asked to complete the PPAQ-C again. Results We used intraclass correlation coefficients to determine the reliability of the PPAQ-C. The intraclass correlation coefficients were 0.77 for total activity (light and above), 0.76 for sedentary activity, 0.75 for light activity, 0.59 for moderate activity, and 0.28 for vigorous activity. The intraclass correlation coefficients were 0.74 for "household and caregiving", 0.75 for "occupational" activities, and 0.34 for "sports/exercise". Validity between the PPAQ-C and accelerometer data was determined by Spearman correlation coefficients. Although there were no significant correlations for moderate activity (r = 0.19, P > 0.05) or vigorous activity (r = 0.15, P > 0.05), there were significant correlations for total activity [light and above; r = 0.35, P < 0.01)] and for light activity (r = 0.33, P < 0.01). Conclusions for Practice The PPAQ-C is reliable and moderately accurate for measuring physical activity in pregnant Chinese women.
The concurrent validity and intrarater reliability of the Microsoft Kinect to measure thoracic kyphosis.

PubMed

Quek, June; Brauer, Sandra G; Treleaven, Julia; Clark, Ross A

2017-09-01

This study aims to investigate the concurrent validity and intrarater reliability of the Microsoft Kinect to measure thoracic kyphosis against the Flexicurve. Thirty-three healthy individuals (age: 31±11.0 years, men: 17, height: 170.2±8.2 cm, weight: 64.2±12.0 kg) participated, with 29 re-examined for intrarater reliability 1-7 days later. Thoracic kyphosis was measured using the Flexicurve and the Microsoft Kinect consecutively in both standing and sitting positions. Both the kyphosis index and angle were calculated. The Microsoft Kinect showed excellent concurrent validity (intraclass correlation coefficient=0.76-0.82) and reliability (intraclass correlation coefficient=0.81-0.98) for measuring thoracic kyphosis (angle and index) in both standing and sitting postures. This study is the first to show that the Microsoft Kinect has excellent validity and intrarater reliability to measure thoracic kyphosis, which is promising for its use in the clinical setting.
Reliability and validity of the Incontinence Quiz-Turkish version.

PubMed

Kara, Kerime C; Çıtak Karakaya, İlkim; Tunalı, Nur; Karakaya, Mehmet G

2018-01-01

The aim of this study was to investigate the reliability and validity of the Turkish version of the Incontinence Quiz, which was developed by Branch et al. (1994), to assess women's knowledge of and attitudes toward urinary incontinence. Comprehensibility of the Turkish version of the 14-item Incontinence Quiz, which was prepared following translation-back translation procedures, was tested on a pilot group of eight women, and its internal reliability, test-retest reliability and construct validity were assessed in 150 women who attended the gynecology clinics of three hospitals in İçel, Turkey. Physical and sociodemographic characteristics and presence of incontinence complaints were also recorded. Data were analyzed at the 0.05 alpha level, using SPSS version 22. The scale had good reliability and validity. The internal reliability coefficient (Cronbach α) was 0.80, test-retest correlation coefficients were 0.83-0.94; and with regard to construct validity, Kaiser-Meyer-Olkin coefficient was 0.76 and Barlett sphericity test was 562.777 (P = 0.000). Turkish version of the Incontinence Quiz had a four-factor structure, with Eigenvalues ranging from 1.17 to 4.08. The Incontinence Quiz-Turkish version is a highly comprehensible, reliable and valid scale, which may be used to assess Turkish-speaking women's knowledge of and attitudes toward urinary incontinence. © 2017 Japan Society of Obstetrics and Gynecology.
Translation, adaptation and validation of a Portuguese version of the Moorehead-Ardelt Quality of Life Questionnaire II.

PubMed

Maciel, João; Infante, Paulo; Ribeiro, Susana; Ferreira, André; Silva, Artur C; Caravana, Jorge; Carvalho, Manuel G

2014-11-01

The prevalence of obesity has increased worldwide. An assessment of the impact of obesity on health-related quality of life (HRQoL) requires specific instruments. The Moorehead-Ardelt Quality of Life Questionnaire II (MA-II) is a widely used instrument to assess HRQoL in morbidly obese patients. The objective of this study was to translate and validate a Portuguese version of the MA-II.The study included forward and backward translations of the original MA-II. The reliability of the Portuguese MA-II was estimated using the internal consistency and test-retest methods. For validation purposes, the Spearman's rank correlation coefficient was used to evaluate the correlation between the Portuguese MA-II and the Portuguese versions of two other questionnaires, the 36-item Short Form Health Survey (SF-36) and the Impact of Weight on Quality of Life-Lite (IWQOL-Lite).One hundred and fifty morbidly obese patients were randomly assigned to test the reliability and validity of the Portuguese MA-II. Good internal consistency was demonstrated by a Cronbach's alpha coefficient of 0.80, and a very good agreement in terms of test-retest reliability was recorded, with an overall intraclass correlation coefficient (ICC) of 0.88. The total sums of MA-II scores and each item of MA-II were significantly correlated with all domains of SF-36 and IWQOL-Lite. A statistically significant negative correlation was found between the MA-II total score and BMI. Moreover, age, gender and surgical status were independent predictors of MA-II total score.A reliable and valid Portuguese version of the MA-II was produced, thus enabling the routine use of MA-II in the morbidly obese Portuguese population.
Development and validation of the occupational identity scale.

PubMed

Melgosa, J

1987-12-01

Ego-identity research utilizing Marcia's (1966) identity statuses has been prolific during the past 15 years. The four types of statuses--achievement, moratorium, foreclosure, diffusion--have become part of the ego-identity development theory. The development of a research tool to study further one of the dimensions of ego-identity development (occupational dimension) was perceived as a need. Therefore, items were created utilizing the criteria established by previous research and content validated by a group of experts. These statements were validated by 417 students from six high schools and colleges. Responses were analyzed and measures of construct and concurrent validity were obtained. Also indexes of internal consistency and item discrimination were estimated. Through factor analysis techniques, four factors were identified for the occupational identity statuses. They accounted for 49 per cent of the total variance. Reliability coefficients ranged between 0.70 and 0.87. Concurrent validity coefficients ranged between 0.38 and 0.79, when correlated with a similar instrument. After deletion of those items that did not contribute significantly to the validity of the instrument, a 28-item Occupational Identity Scale was established.

Estimating Seven Coefficients of Pairwise Relatedness Using Population-Genomic Data

PubMed Central

Ackerman, Matthew S.; Johri, Parul; Spitze, Ken; Xu, Sen; Doak, Thomas G.; Young, Kimberly; Lynch, Michael

2017-01-01

Population structure can be described by genotypic-correlation coefficients between groups of individuals, the most basic of which are the pairwise relatedness coefficients between any two individuals. There are nine pairwise relatedness coefficients in the most general model, and we show that these can be reduced to seven coefficients for biallelic loci. Although all nine coefficients can be estimated from pedigrees, six coefficients have been beyond empirical reach. We provide a numerical optimization procedure that estimates all seven reduced coefficients from population-genomic data. Simulations show that the procedure is nearly unbiased, even at 3× coverage, and errors in five of the seven coefficients are statistically uncorrelated. The remaining two coefficients have a negative correlation of errors, but their sum provides an unbiased assessment of the overall correlation of heterozygosity between two individuals. Application of these new methods to four populations of the freshwater crustacean Daphnia pulex reveal the occurrence of half siblings in our samples, as well as a number of identical individuals that are likely obligately asexual clone mates. Statistically significant negative estimates of these pairwise relatedness coefficients, including inbreeding coefficients that were typically negative, underscore the difficulties that arise when interpreting genotypic correlations as estimations of the probability that alleles are identical by descent. PMID:28341647
Validation of the Walking Impairment Questionnaire for Spanish patients.

PubMed

Lozano, Francisco S; March, José R; González-Porras, José R; Carrasco, Eduardo; Lobos, José M; Areitio-Aurtena, Alix

2013-09-01

The Walking Impairment Questionnaire (WIQ) is a short, easy to complete, disease-specific questionnaire to assess intermittent claudication. A Spanish version of the WIQ for Hispanic Americans has recently been validated in Texas, but it needs to be validated for European Spanish people. After translation and cultural adaptation of the WIQ, 920 patients with intermittent claudication (ankle brachial index < 0.9) completed two questionnaires (Spanish version of the WIQ and European Quality of Life 5 Dimension [EQ-5D]). The validity of the WIQ was determined by correlating WIQ and EQ-5D. Test-retest reliability and internal consistency were determined using the intra-class correlation coefficient (ICC) and Cronbach's alpha, respectively. The three domains of the WIQ were moderately correlated with the EQ-5D health outcome (r = 0.54 to 0.60; p < 0.001). Test-retest reliabilities ranged from ICC = 0.89 to 0.91 and internal consistency (Cronbach's alpha = 0.92) was high. The Spanish version of the WIQ for European Spanish patients was valid and reproducible, suggesting that it could be used in Spanish patients with intermittent claudication.
Validity of the Nintendo Wii® balance board for the assessment of standing balance in Parkinson's disease.

PubMed

Holmes, Jeffrey D; Jenkins, Mary E; Johnson, Andrew M; Hunt, Michael A; Clark, Ross A

2013-04-01

Impaired postural stability places individuals with Parkinson's at an increased risk for falls. Given the high incidence of fall-related injuries within this population, ongoing assessment of postural stability is important. To evaluate the validity of the Nintendo Wii(®) balance board as a measurement tool for the assessment of postural stability in individuals with Parkinson's. Twenty individuals with Parkinson's participated. Subjects completed testing on two balance tasks with eyes open and closed on a Wii(®) balance board and biomechanical force platform. Bland-Altman plots and a two-way, random-effects, single measure intraclass correlation coefficient model were used to assess concurrent validity of centre-of-pressure data. Concurrent validity was demonstrated to be excellent across balance tasks (intraclass correlation coefficients = 0.96, 0.98, 0.92, 0.94). This study suggests that the Wii(®) balance board is a valid tool for the quantification of postural stability among individuals with Parkinson's.
Validation of EORTC IN-PATSAT32 for Chinese patients with gastrointestinal cancer

PubMed Central

Zhang, Jishui; Xie, Shumin; Liu, Jiahao; Sun, Weilin; Guo, Hui; Hu, Yingbin; Gao, Xin

2014-01-01

Purpose To test the psychometric properties and applicability of the European Organization for Research and Treatment of Cancer In-patient Satisfaction with Care Questionnaire 32 (EORTC IN-PATSAT32) for Chinese patients with gastrointestinal cancer. Patients and methods A total of 106 inpatients with gastrointestinal cancer at Cangzhou Center Hospital were enrolled in this study. All were treated at Cangzhou Center Hospital from July 2013–March 2014. All participants self-administered the EORTC IN-PATSAT32 and EORTC Quality of Life Questionnaire – Core 30 (EORTC QLQ-C30). Results The Cronbach’s α coefficients were >0.70 for all scales of the EORTC IN-PATSAT32. Multitrait scaling analysis showed that all-item scale correlation coefficients met the standard of convergent validity, while only 50.0% met the standard of discriminant validity. A weak correlation was found between the scales and single items of the EORTC IN-PATSAT32 and EORTC QLQ-C30. Conclusion The EORTC IN-PATSAT32 appears to be a reliable, valid, and acceptable instrument for measuring patient satisfaction among Chinese patients with gastrointestinal cancer. PMID:25258522
Reliability and Validity of an Internet-based Questionnaire Measuring Lifetime Physical Activity

PubMed Central

De Vera, Mary A.; Ratzlaff, Charles; Doerfling, Paul; Kopec, Jacek

2010-01-01

Lifetime exposure to physical activity is an important construct for evaluating associations between physical activity and disease outcomes, given the long induction periods in many chronic diseases. The authors' objective in this study was to evaluate the measurement properties of the Lifetime Physical Activity Questionnaire (L-PAQ), a novel Internet-based, self-administered instrument measuring lifetime physical activity, among Canadian men and women in 2005–2006. Reliability was examined using a test-retest study. Validity was examined in a 2-part study consisting of 1) comparisons with previously validated instruments measuring similar constructs, the Lifetime Total Physical Activity Questionnaire (LT-PAQ) and the Chasan-Taber Physical Activity Questionnaire (CT-PAQ), and 2) a priori hypothesis tests of constructs measured by the L-PAQ. The L-PAQ demonstrated good reliability, with intraclass correlation coefficients ranging from 0.67 (household activity) to 0.89 (sports/recreation). Comparison between the L-PAQ and the LT-PAQ resulted in Spearman correlation coefficients ranging from 0.41 (total activity) to 0.71 (household activity); comparison between the L-PAQ and the CT-PAQ yielded coefficients of 0.58 (sports/recreation), 0.56 (household activity), and 0.50 (total activity). L-PAQ validity was further supported by observed relations between the L-PAQ and sociodemographic variables, consistent with a priori hypotheses. Overall, the L-PAQ is a useful instrument for assessing multiple domains of lifetime physical activity with acceptable reliability and validity. PMID:20876666
Reliability and validity of an internet-based questionnaire measuring lifetime physical activity.

PubMed

De Vera, Mary A; Ratzlaff, Charles; Doerfling, Paul; Kopec, Jacek

2010-11-15

Lifetime exposure to physical activity is an important construct for evaluating associations between physical activity and disease outcomes, given the long induction periods in many chronic diseases. The authors' objective in this study was to evaluate the measurement properties of the Lifetime Physical Activity Questionnaire (L-PAQ), a novel Internet-based, self-administered instrument measuring lifetime physical activity, among Canadian men and women in 2005-2006. Reliability was examined using a test-retest study. Validity was examined in a 2-part study consisting of 1) comparisons with previously validated instruments measuring similar constructs, the Lifetime Total Physical Activity Questionnaire (LT-PAQ) and the Chasan-Taber Physical Activity Questionnaire (CT-PAQ), and 2) a priori hypothesis tests of constructs measured by the L-PAQ. The L-PAQ demonstrated good reliability, with intraclass correlation coefficients ranging from 0.67 (household activity) to 0.89 (sports/recreation). Comparison between the L-PAQ and the LT-PAQ resulted in Spearman correlation coefficients ranging from 0.41 (total activity) to 0.71 (household activity); comparison between the L-PAQ and the CT-PAQ yielded coefficients of 0.58 (sports/recreation), 0.56 (household activity), and 0.50 (total activity). L-PAQ validity was further supported by observed relations between the L-PAQ and sociodemographic variables, consistent with a priori hypotheses. Overall, the L-PAQ is a useful instrument for assessing multiple domains of lifetime physical activity with acceptable reliability and validity.
Translation of the Neck Disability Index and validation of the Greek version in a sample of neck pain patients.

PubMed

Trouli, Marianna N; Vernon, Howard T; Kakavelakis, Kyriakos N; Antonopoulou, Maria D; Paganas, Aristofanis N; Lionis, Christos D

2008-07-22

Neck pain is a highly prevalent condition resulting in major disability. Standard scales for measuring disability in patients with neck pain have a pivotal role in research and clinical settings. The Neck Disability Index (NDI) is a valid and reliable tool, designed to measure disability in activities of daily living due to neck pain. The purpose of our study was the translation and validation of the NDI in a Greek primary care population with neck complaints. The original version of the questionnaire was used. Based on international standards, the translation strategy comprised forward translations, reconciliation, backward translation and pre-testing steps. The validation procedure concerned the exploration of internal consistency (Cronbach alpha), test-retest reliability (Intraclass Correlation Coefficient, Bland and Altman method), construct validity (exploratory factor analysis) and responsiveness (Spearman correlation coefficient, Standard Error of Measurement and Minimal Detectable Change) of the questionnaire. Data quality was also assessed through completeness of data and floor/ceiling effects. The translation procedure resulted in the Greek modified version of the NDI. The latter was culturally adapted through the pre-testing phase. The validation procedure raised a large amount of missing data due to low applicability, which were assessed with two methods. Floor or ceiling effects were not observed. Cronbach alpha was calculated as 0.85, which was interpreted as good internal consistency. Intraclass correlation coefficient was found to be 0.93 (95% CI 0.84-0.97), which was considered as very good test-retest reliability. Factor analysis yielded one factor with Eigenvalue 4.48 explaining 44.77% of variance. The Spearman correlation coefficient (0.3; P = 0.02) revealed some relation between the change score in the NDI and Global Rating of Change (GROC). The SEM and MDC were calculated as 0.64 and 1.78 respectively. The Greek version of the NDI measures
Translation of the Neck Disability Index and validation of the Greek version in a sample of neck pain patients

PubMed Central

Trouli, Marianna N; Vernon, Howard T; Kakavelakis, Kyriakos N; Antonopoulou, Maria D; Paganas, Aristofanis N; Lionis, Christos D

2008-01-01

Background Neck pain is a highly prevalent condition resulting in major disability. Standard scales for measuring disability in patients with neck pain have a pivotal role in research and clinical settings. The Neck Disability Index (NDI) is a valid and reliable tool, designed to measure disability in activities of daily living due to neck pain. The purpose of our study was the translation and validation of the NDI in a Greek primary care population with neck complaints. Methods The original version of the questionnaire was used. Based on international standards, the translation strategy comprised forward translations, reconciliation, backward translation and pre-testing steps. The validation procedure concerned the exploration of internal consistency (Cronbach alpha), test-retest reliability (Intraclass Correlation Coefficient, Bland and Altman method), construct validity (exploratory factor analysis) and responsiveness (Spearman correlation coefficient, Standard Error of Measurement and Minimal Detectable Change) of the questionnaire. Data quality was also assessed through completeness of data and floor/ceiling effects. Results The translation procedure resulted in the Greek modified version of the NDI. The latter was culturally adapted through the pre-testing phase. The validation procedure raised a large amount of missing data due to low applicability, which were assessed with two methods. Floor or ceiling effects were not observed. Cronbach alpha was calculated as 0.85, which was interpreted as good internal consistency. Intraclass correlation coefficient was found to be 0.93 (95% CI 0.84–0.97), which was considered as very good test-retest reliability. Factor analysis yielded one factor with Eigenvalue 4.48 explaining 44.77% of variance. The Spearman correlation coefficient (0.3; P = 0.02) revealed some relation between the change score in the NDI and Global Rating of Change (GROC). The SEM and MDC were calculated as 0.64 and 1.78 respectively. Conclusion
Validation of the questionnaire on hand function assessment in leprosy.

PubMed

Ferreira, Telma Leonel; Alvarez, Rosicler Rocha Aiza; Virmond, Marcos da Cunha Lopes

2012-06-01

To validate the psychometric properties of the questionnaire on hand function assessment in leprosy. Study conducted with a convenience sample of 101 consecutive patients in Brasília (Central-Western Brazil), from June 2008 to July 2009. The individuals were adults affected by leprosy, with impairment of the ulnar, median and radial nerves. Interobservers and intraobserver reproducibility was analyzed through successive interviews, and construct validity was analyzed through association between age, clinical form of leprosy, duration of nerve injury, grip and pinch strength measured with a dynamometer, sensibility test performed with Semmes-Weinstein monofilaments and manual ability assessment using the Jebsen test of hand function. Pondered kappa coefficient was calculated and a Bland-Altman plot was constructed to assess the reproducibility of the instrument. For internal consistency, Cronbach's alpha coefficient was utilized. Pearson's correlation coefficient was calculated and a multiple regression model was used. The pondered kappa values for interobservers and intraobserver assessments ranged from 0.86 to 0.97 and from 0.85 to 0.97, respectively. The value of Cronbach's alpha coefficient was 0.967. Pearson's correlation coefficient showed an association (p < 0.001) among duration of nerve injury, grip and pinch strength, cutaneous sensibility and mean score in the Jebsen Test. The mean score of the questionnaire on hand functional assessment in leprosy was associated with operational classification of leprosy, duration of nerve injury, grip strength, cutaneous sensibility and manual ability (p < 0.0001 for the model as a whole). The questionnaire on hand functional assessment in leprosy presents almost perfect interobservers and intraobserver reproducibility, high internal consistency and correlation with operational classification of leprosy, duration of nerve injury, grip strength, cutaneous sensibility in the hands and manual ability.
Portuguese-language version of the Chronic Respiratory Questionnaire: a validity and reproducibility study.

PubMed

Moreira, Graciane Laender; Pitta, Fábio; Ramos, Dionei; Nascimento, Cinthia Sousa Carvalho; Barzon, Danielle; Kovelis, Demétria; Colange, Ana Lúcia; Brunetto, Antonio Fernando; Ramos, Ercy Mara Cipulo

2009-08-01

To determine the validity and reproducibility of a Portuguese-language version of the Chronic Respiratory Questionnaire (CRQ) in patients with COPD. A Portuguese-language version of the CRQ (provided by McMaster University, the holder of the questionnaire copyright) was applied to 50 patients with COPD (70 +/- 8 years of age; 32 males; FEV1 = 47 +/- 18% of predicted) on two occasions, one week apart. The CRQ has four domains (dyspnea, fatigue, emotional function, and mastery) and was applied as an interviewer-administered instrument. The Saint George's Respiratory Questionnaire (SGRQ), already validated for use in Brazil, was used as the criterion for validation. Spirometry and the six-minute walk test (6MWT) were performed to analyze the correlations with the CRQ scores. There were no significant CRQ test-retest differences (p > 0.05 for all domains). The test-retest intraclass correlation coefficient was 0.98, 0.97, 0.98 and 0.95 for the dyspnea, fatigue, emotional function and mastery domains, respectively. The Cronbach's alpha coefficient was 0.91. The CRQ domains correlated significantly with the SGRQ domains (-0.30 < r < -0.67; p < 0.05). There were no significant correlations between spirometric variables and the CRQ domains or between the CRQ domains and the 6MWT, with the exception of the fatigue domain (r = 0.30; p = 0.04). The Portuguese-language version of the CRQ proved to be reproducible and valid for use in Brazilian patients with COPD.
Spanish validation of Bad Sobernheim Stress Questionnaire (BSSQ (brace).es) for adolescents with braces

PubMed Central

2010-01-01

Background As a result of scientific and medical professionals gaining interest in Stress and Health Related Quality of Life (HRQL), the aim of our research is, thus, to validate into Spanish the German questionnaire Bad Sobernheim Stress Questionnaire (BSSQ) (mit Korsett), for adolescents wearing braces. Methods The methodology used adheres to literature on trans-cultural adaptation by doing a translation and a back translation; it involved 35 adolescents, ages ranging between 10 and 16, with Adolescent Idiopathic Scoliosis (AIS) and wearing the same kind of brace (Rigo System Chêneau Brace). The materials used were a socio-demographics data questionnaire, the SRS-22 and the Spanish version of BSSQ(brace).es. The statistical analysis calculated the reliability (test-retest reliability and internal consistency) and the validity (convergent and construct validity) of the BSSQ (brace).es. Results BSSQ(brace).es is reliable because of its satisfactory internal consistency (Cronbach's alpha coefficient was 0.809, p < 0.001) and temporal stability (test-retest method with a Pearson correlation coefficient of 0.902 (p < 0.01)). It demonstrated convergent validity with SRS-22 since the Pearson correlation coefficient was 0.656 (p < 0.01). By undertaking an Exploratory Principal Components Analysis, a latent structure was found based on two Components which explicate the variance at 60.8%. Conclusions BSSQ (brace).es is reliable and valid and can be used with Spanish adolescents to assess the stress level caused by the brace. PMID:20633253
Validation of the Chinese Version of the Quality of Nursing Work Life Scale

PubMed Central

Fu, Xia; Xu, Jiajia; Song, Li; Li, Hua; Wang, Jing; Wu, Xiaohua; Hu, Yani; Wei, Lijun; Gao, Lingling; Wang, Qiyi; Lin, Zhanyi; Huang, Huigen

2015-01-01

Quality of Nursing Work Life (QNWL) serves as a predictor of a nurse’s intent to leave and hospital nurse turnover. However, QNWL measurement tools that have been validated for use in China are lacking. The present study evaluated the construct validity of the QNWL scale in China. A cross-sectional study was conducted conveniently from June 2012 to January 2013 at five hospitals in Guangzhou, which employ 1938 nurses. The participants were asked to complete the QNWL scale and the World Health Organization Quality of Life abbreviated version (WHOQOL-BREF). A total of 1922 nurses provided the final data used for analyses. Sixty-five nurses from the first investigated division were re-measured two weeks later to assess the test-retest reliability of the scale. The internal consistency reliability of the QNWL scale was assessed using Cronbach’s α. Test-retest reliability was assessed using the intra-class correlation coefficient (ICC). Criterion-relation validity was assessed using the correlation of the total scores of the QNWL and the WHOQOL-BREF. Construct validity was assessed with the following indices: χ2 statistics and degrees of freedom; relative mean square error of approximation (RMSEA); the Akaike information criterion (AIC); the consistent Akaike information criterion (CAIC); the goodness-of-fit index (GFI); the adjusted goodness of fit index; and the comparative fit index (CFI). The findings demonstrated high internal consistency (Cronbach’s α = 0.912) and test-retest reliability (interclass correlation coefficient = 0.74) for the QNWL scale. The chi-square test (χ2 = 13879.60, df [degree of freedom] = 813 P = 0.0001) was significant. The RMSEA value was 0.091, and AIC = 1806.00, CAIC = 7730.69, CFI = 0.93, and GFI = 0.74. The correlation coefficient between the QNWL total scores and the WHOQOL-BREF total scores was 0.605 (p<0.01). The QNWL scale was reliable and valid in Chinese-speaking nurses and could be used as a clinical and research
Validation of the Sinhala version of the Repeatable Battery for Assessment of Neuropsychological Status (RBANS)

PubMed

Suraweera, Chathurie; Anandakumar, D; Dahanayake, D; Subendran, M; Perera, U T; Hanwella, Raveen; de Silva, Varuni

2016-12-30

Only the Mini mental state examination (MMSE) and Montreal Cognitive Assessment scale have been validated in a Sri Lankan population for the assessment of cognitive functions. Both tests are deficient in the number of domains assessed. Therefore validation of Repeatable Battery for Assessment of Neuropsychological Status is important as it assesses most of the cognitive domains. To culturally adapt RBANS and investigate the validity and reliability of culturally adapted RBANS (RBANS-S). Fifty four participants with major neurocognitive disorder and 60 normal controls aged >50 were administered with RBANS-S at the Cognitive Assessment Unit, Faculty of Medicine, Colombo and National Hospital of Sri Lanka. The participants were selected after a detailed clinical assessment according to Diagnostic and Statistical Manual – 5 criteria. Data were analysed using SPSS data package. The mean age of the sample was 69.5 years. RBANS-S total scale correlated highly with MMSE total score, (Pearson correlational coefficient = 0.793 p=0.01). Criterion validity was assessed using receiver operating curve characteristic analysis and the area under the curve was 0.937. RBANS-S showed strong concurrent validity us indicated by its significant correlations with the MMSE. All of the RBANS-S subtests demonstrated significant correlations with the MMSE subsets. The sensitivity and specificity for RBANS-S was 89% and 85% respectively at a totals score of 80.5. The RBANS-S yielded a reliability coefficient of 0.929. Culturally adapted RBANS-S is a valid and reliable instrument which can be used in assessment of cognitive functions.
Validity of the occupational sitting and physical activity questionnaire.

PubMed

Chau, Josephine Y; Van Der Ploeg, Hidde P; Dunn, Scott; Kurko, John; Bauman, Adrian E

2012-01-01

Sitting at work is an emerging occupational health risk. Few instruments designed for use in population-based research measure occupational sitting and standing as distinct behaviors. This study aimed to develop and validate brief measure of occupational sitting and physical activity. A convenience sample (n = 99, 61% female) was recruited from two medium-sized workplaces and by word-of-mouth in Sydney, Australia. Participants completed the newly developed Occupational Sitting and Physical Activity Questionnaire (OSPAQ) and a modified version of the MONICA Optional Study on Physical Activity Questionnaire (modified MOSPA-Q) twice, 1 wk apart. Participants also wore an ActiGraph accelerometer for the 7 d in between the test and retest. Analyses determined test-retest reliability with intraclass correlation coefficients and assessed criterion validity against accelerometers using the Spearman ρ. The test-retest intraclass correlation coefficients for occupational sitting, standing, and walking for OSPAQ ranged from 0.73 to 0.90, while that for the modified MOSPA-Q ranged from 0.54 to 0.89. Comparison of sitting measures with accelerometers showed higher Spearman correlations for the OSPAQ (r = 0.65) than for the modified MOSPA-Q (r = 0.52). Criterion validity correlations for occupational standing and walking measures were comparable for both instruments with accelerometers (standing: r = 0.49; walking: r = 0.27-0.29). The OSPAQ has excellent test-retest reliability and moderate validity for estimating time spent sitting and standing at work and is comparable to existing occupational physical activity measures for assessing time spent walking at work. The OSPAQ brief instrument measures sitting and standing at work as distinct behaviors and would be especially suitable in national health surveys, prospective cohort studies, and other studies that are limited by space constraints for questionnaire items.
Reliability and validity of the Turkish version of the Berg Balance Scale.

PubMed

Sahin, Fusun; Yilmaz, Figen; Ozmaden, Asli; Kotevolu, Nurdan; Sahin, Tulay; Kuran, Banu

2008-01-01

The purpose of this study was to develop a Turkish version of the Berg Balance Scale (BBS) and assess its reliability and validity. Sixty healthy volunteers older than 65 years were included in to the study. Subjects who had lower extremity amputation, or were armchair or bedridden were excluded. After translation process, the Turkish version of the scale was administered to each participant twice with an interval of 2 weeks. The intraclass correlation coefficient (ICC) was calculated to assess intra- and inter-observer reliability. Chronbach alpha was calculated to evaluate internal consistency of the total BBS score. Interclass correlation coefficient was calcuated to examine test-retest reliability. Convergent validity was assessed by correlating the scale with Modified Barthel Index (MBI) and Timed Up and Go Test (TUG). Construct validity was assessed with factor analysis. The mean age in years of the participants were 77.00+/-5.67 (range: 67-92 yrs). The ICC for intra- and inter- observer reliability was 0.98 (p<0.0001) and 0.97 (p<0.0001), respectively. Chronbach alpha of the Turkish version of the BBS was 0.98. The test-retest reliability (ICC) of the Turkish version of the BBS was determined as 0.98 for the total score, and ranged from 0.86-0.99 for individual items. In terms of validity, the Turkish version of the BBS was correlated with the MBI (in positive direction) and TUG (in negative direction) (r=0.67 p<0.0001; r=-0.75 p<0.0001, respectively). The Turkish version of the BBS is a reliable and valid scale to be used in balance assessment of Turkish older adults.
Cross-Cultural Adaptation, Validation, and Reliability Testing of the Modified Oswestry Disability Questionnaire in Persian Population with Low Back Pain.

PubMed

Baradaran, Aslan; Ebrahimzadeh, Mohammad H; Birjandinejad, Ali; Kachooei, Amir Reza

2016-04-01

Prospective study. We aimed to validate the Persian version of the modified Oswestry disability questionnaire (MODQ) in patients with low back pain. Modified Oswestry low back pain disability questionnaire is a well-known condition-specific outcome measure that helps quantify disability in patients with lumbar syndromes. To test the validity in a pilot study, the Persian MODQ was administered to 25 individuals with low back pain. We then enrolled 200 consecutive patients with low back pain to fill the Persian MODQ as well as the short form 36 (SF-36) questionnaire. Convergent validity of the MODQ was tested using the Spearman's correlation coefficient between the MODQ and SF-36 subscales. Intraclass correlation coefficient (ICC) and Cronbach's α coefficient were measured to test the reliability between test and retest and internal consistency of all items, respectively. ICC for individual items ranged from 0.43 to 0.80 showing good reliability and reproducibility of each individual item. Cronbach's α coefficient was 0.69 showing good internal consistency across all 10 items of the Persian MODQ. Total MODQ score showed moderate to strong correlation with the eight subscales and the two domains of the SF-36. The highest correlation was between the MODQ and the physical functioning subscale of the SF-36 (r=-0.54, p<0.001) and the physical component domain of the SF-36 (r=-0.55, p<0.001) showing that MODQ is measuring what it is supposed to measure in terms of disability and physical function. Persian version of the MODQ is a valid and reliable tool for the assessment of the disability following low back pain.
Transcultural validation of the Oxford Shoulder Score for the French-speaking population.

PubMed

Tuton, D; Barbe, C; Salmon, J-H; Dramé, M; Nérot, C; Ohl, X

2016-09-01

Patient-reported outcome measures (PROMs) have been gaining in popularity over the last decade. The Oxford Shoulder Score (OSS) is a well-established self-administered questionnaire for shoulder evaluation adapted for the English-speaking population. The aim of the present study was to develop a translation and a transcultural adaptation of the OSS and to assess its validity in native French-speaker patients with shoulder pain. The translation process was carried out following a translation/back-translation methodology by two translators. All patients completed the French OSS, the Subjective Shoulder Value (SSV), and the Constant score. Internal consistency was tested using Cronbach's α coefficient. Validity was assessed by calculating the Pearson correlation coefficient between the OSS and the Constant score and the SSV. One hundred forty-four patients suffering from degenerative or inflammatory diseases of the shoulder were included in this study. The average time required to complete the French OSS was 2min and 45s. Seventy patients were asked to complete the questionnaire twice (test/retest reliability). Internal consistency was high with Cronbach's α coefficient=0.93. The intraclass correlation coefficient was 0.91 (95% CI: 0.88-0.94) for test/retest reliability. The French OSS score was significantly correlated with the Constant-Murley score (r=0.73 and P<0.0001) and with the SSV (r=0.68 and P<0.0001). The present study shows that the French version of the OSS is reliable, valid, and reproducible. The sensitivity to change now needs to be evaluated. This score was adapted to the French-speaking population for the self-assessment of patients with degenerative or inflammatory disorders of the shoulder. Level 1, Test of previously developed criteria, diagnostic test study. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Reliability and validity of the Daily Cognitive-Communication and Sleep Profile: a new instrument for monitoring sleep, wakefulness and daytime function.

PubMed

Fung, Christina Hoi Ling; Nguyen, Michelle; Moineddin, Rahim; Colantonio, Angela; Wiseman-Hakes, Catherine

2014-06-01

The Daily Cognitive Communicative and Sleep Profile (DCCASP) is a seven-item instrument that captures daily subjective sleep quality, perceived mood, cognitive, and communication functions. The objective of this study was to evaluate the reliability and validity of the DCCASP. The DCCASP was self-administered daily to a convenience sample of young adults (n = 54) for two two-week blocks, interspersed with a two-week rest period. Afterwards, participants completed the Pittsburgh Sleep Quality Index (PSQI). Internal consistency and criterion validity were calculated by Cronbach's α coefficient, Concordance Correlation Coefficient (CCC), and Spearman rank (rs) correlation coefficient, respectively. Results indicated high internal consistency (Cronbach-s α = 0.864-0.938) among mean ratings of sleep quality on the DCCASP. There were significant correlations between mean ratings of sleep quality and all domains (rs=0.38-0.55, p<0.0001). Criterion validity was established between mean sleep quality ratings on the DCCASP and PSQI (rs=0.40, p<0.001). The DCCASP is a reliable and valid self-report instrument to monitor daily sleep quality and perceived mood, cognitive, and communication functions over time, amongst a normative sample of young adults. Further studies on its psychometric properties are necessary to clarify its utility in a clinical population. Copyright © 2014 John Wiley & Sons, Ltd.
Virial Coefficients for the Liquid Argon

NASA Astrophysics Data System (ADS)

Korth, Micheal; Kim, Saesun

2014-03-01

We begin with a geometric model of hard colliding spheres and calculate probability densities in an iterative sequence of calculations that lead to the pair correlation function. The model is based on a kinetic theory approach developed by Shinomoto, to which we added an interatomic potential for argon based on the model from Aziz. From values of the pair correlation function at various values of density, we were able to find viral coefficients of liquid argon. The low order coefficients are in good agreement with theoretical hard sphere coefficients, but appropriate data for argon to which these results might be compared is difficult to find.
Validation of the Penn Acoustic Neuroma Quality-of-Life Scale (PANQOL) for Spanish-Speaking Patients.

PubMed

Medina, Maria Del Mar; Carrillo, Alvaro; Polo, Ruben; Fernandez, Borja; Alonso, Daniel; Vaca, Miguel; Cordero, Adela; Perez, Cecilia; Muriel, Alfonso; Cobeta, Ignacio

2017-04-01

Objective To perform translation, cross-cultural adaptation, and validation of the Penn Acoustic Neuroma Quality-of-Life Scale (PANQOL) to the Spanish language. Study Design Prospective study. Setting Tertiary neurotologic referral center. Subjects and Methods PANQOL was translated and translated back, and a pretest trial was performed. The study included 27 individuals diagnosed with vestibular schwannoma. Inclusion criteria were adults with untreated vestibular schwannoma, diagnosed in the past 12 months. Feasibility, internal consistency, test-retest reliability, construct validity, and ceiling and floor effects were assessed for the present study. Results The mean overall score of the PANQOL was 69.21 (0-100 scale, lowest to highest quality of life). Cronbach's α was 0.87. Intraclass correlation coefficient was performed for each item, with an overall score of 0.92. The κ coefficient scores were between moderate and almost perfect in more than 92% of patients. Anxiety and energy domains of the PANQOL were correlated with both physical and mental components of the SF-12. Hearing, balance, and pain domains were correlated with the SF-12 physical component. Facial and general domains were not significantly correlated with any component of the SF-12. Furthermore, the overall score of the PANQOL was correlated with the physical component of the SF-12. Conclusion Feasibility, internal consistency, reliability, and construct validity outcomes in the current study support the validity of the Spanish version of the PANQOL.

Validity of a self-administered food frequency questionnaire in the estimation of heterocyclic aromatic amines.

PubMed

Iwasaki, Motoki; Mukai, Tomomi; Takachi, Ribeka; Ishihara, Junko; Totsuka, Yukari; Tsugane, Shoichiro

2014-08-01

Clarification of the putative etiologic role of heterocyclic aromatic amines (HAAs) in the development of cancer requires a validated assessment tool for dietary HAAs. This study primarily aimed to evaluate the validity of a food frequency questionnaire (FFQ) in estimating HAA intake, using 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) level in human hair as the reference method. We first updated analytical methods of PhIP using liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-ESI/MS/MS) and measured 44 fur samples from nine rats from a feeding study as part-verification of the quantitative performance of LC-ESI/MS/MS. We next measured PhIP level in human hair samples from a validation study of the FFQ (n = 65). HAA intake from the FFQ was estimated using information on intake from six fish items and seven meat items and data on HAA content in each food item. Correlation coefficients between PhIP level in human hair and HAA intake from the FFQ were calculated. The animal feeding study of PhIP found a significant dose-response relationship between dosage and PhIP in rat fur. Mean level was 53.8 pg/g hair among subjects with values over the limit of detection (LOD) (n = 57). We found significant positive correlation coefficients between PhIP in human hair and HAA intake from the FFQ, with Spearman rank correlation coefficients of 0.35 for all subjects, 0.21 for subjects with over LOD values, and 0.34 for subjects with over limit of quantification. Findings from the validation study suggest that the FFQ is reasonably valid for the assessment of HAA intake.
Validity and reliability of the Questionnaire for Compliance with Standard Precaution

PubMed Central

Valim, Marília Duarte; Marziale, Maria Helena Palucci; Hayashida, Miyeko; Rocha, Fernanda Ludmilla Rossi; Santos, Jair Lício Ferreira

2015-01-01

ABSTRACT OBJECTIVE : To evaluate the validity and reliability of the Questionnaire for Compliance with Standard Precaution for nurses. METHODS : This methodological study was conducted with 121 nurses from health care facilities in Sao Paulo’s countryside, who were represented by two high-complexity and by three average-complexity health care facilities. Internal consistency was calculated using Cronbach’s alpha and stability was calculated by the intraclass correlation coefficient, through test-retest. Convergent, discriminant, and known-groups construct validity techniques were conducted. RESULTS : The questionnaire was found to be reliable (Cronbach’s alpha: 0.80; intraclass correlation coefficient: (0.97) In regards to the convergent and discriminant construct validity, strong correlation was found between compliance to standard precautions, the perception of a safe environment, and the smaller perception of obstacles to follow such precautions (r = 0.614 and r = 0.537, respectively). The nurses who were trained on the standard precautions and worked on the health care facilities of higher complexity were shown to comply more (p = 0.028 and p = 0.006, respectively). CONCLUSIONS : The Brazilian version of the Questionnaire for Compliance with Standard Precaution was shown to be valid and reliable. Further investigation must be conducted with nurse samples that are more representative of the Brazilian reality. The use of the questionnaire may support the creation of educational measures considering the possible gaps that can be identified, focusing on the workers’ health and on the patients’ safety. PMID:26759967
Development and initial validation of primary care provider mental illness management and team-based care self-efficacy scales.

PubMed

Loeb, Danielle F; Crane, Lori A; Leister, Erin; Bayliss, Elizabeth A; Ludman, Evette; Binswanger, Ingrid A; Kline, Danielle M; Smith, Meredith; deGruy, Frank V; Nease, Donald E; Dickinson, L Miriam

Develop and validate self-efficacy scales for primary care provider (PCP) mental illness management and team-based care participation. We developed three self-efficacy scales: team-based care (TBC), mental illness management (MIM), and chronic medical illness (CMI). We developed the scales using Bandura's Social Cognitive Theory as a guide. The survey instrument included items from previously validated scales on team-based care and mental illness management. We administered a mail survey to 900 randomly selected Colorado physicians. We conducted exploratory principal factor analysis with oblique rotation. We constructed self-efficacy scales and calculated standardized Cronbach's alpha coefficients to test internal consistency. We calculated correlation coefficients between the MIM and TBC scales and previously validated measures related to each scale to evaluate convergent validity. We tested correlations between the TBC and the measures expected to correlate with the MIM scale and vice versa to evaluate discriminant validity. PCPs (n=402, response rate=49%) from diverse practice settings completed surveys. Items grouped into factors as expected. Cronbach's alphas were 0.94, 0.88, and 0.83 for TBC, MIM, and CMI scales respectively. In convergent validity testing, the TBC scale was correlated as predicted with scales assessing communications strategies, attitudes toward teams, and other teamwork indicators (r=0.25 to 0.40, all statistically significant). Likewise, the MIM scale was significantly correlated with several items about knowledge and experience managing mental illness (r=0.24 to 41, all statistically significant). As expected in discriminant validity testing, the TBC scale had only very weak correlations with the mental illness knowledge and experience managing mental illness items (r=0.03 to 0.12). Likewise, the MIM scale was only weakly correlated with measures of team-based care (r=0.09 to.17). This validation study of MIM and TBC self-efficacy scales
Validation of a short, qualitative food frequency questionnaire in French adults participating in the MONA LISA-NUT study 2005-2007.

PubMed

Giovannelli, Jonathan; Dallongeville, Jean; Wagner, Aline; Bongard, Vanina; Laillet, Brigitte; Marecaux, Nadine; Ruidavets, Jean Bernard; Haas, Bernadette; Ferrieres, Jean; Arveiler, Dominique; Simon, Chantal; Dauchet, Luc

2014-04-01

Food frequency questionnaires (FFQs) are often used to evaluate individuals' food intakes in epidemiologic studies because of their simplicity and low cost. To assess the validity of a short (24 items), qualitative FFQ used in the MONA LISA-NUT study. Cross-sectional study of a representative sample in three French counties. The sample included 2,630 participants aged 35 to 65 years from the MONA LISA-NUT study. Food consumption was measured with the FFQ and via food records for 3 consecutive days. Plasma fatty acids were measured from a subset of participants. The FFQ items' validity was assessed by calculating crude and deattenuated Pearson correlation coefficients between frequencies reported by the FFQ and average weights reported by the food records. Furthermore, the validity of some items of the FFQ measuring the consumption of fatty foods was assessed by calculating Pearson correlation coefficients between frequencies of consumption of these foods and dosages of the corresponding plasma fatty acids: fish and eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), olive oil and oleic acid, margarine and elaidic acid, and dairy products and pentadecanoic and heptadecanoic acids. The mean of the deattenuated Pearson correlation coefficients for all items was 0.46, with values ranging from 0.22 (fried food) to 0.77 (breakfast cereal). The correlation coefficient was ≤ 0.4 for one third of the 24 items. Moderate correlations were found between fish and EPA/DHA (EPA: r=0.43, 95% CI 0.33 to 0.51; DHA: r=0.39, 95% CI 0.30 to 0.47), but not for other food items. One third of the 24 items in the short, qualitative FFQ evaluated here were not sufficiently valid. However, for the food groups most commonly studied in the literature, this FFQ had the same degree of validity as other questionnaires designed to classify subjects according to their level of intake. Copyright © 2014 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.
Nuclear Overhauser Enhancement imaging of glioblastoma at 7 Tesla: region specific correlation with apparent diffusion coefficient and histology.

PubMed

Paech, Daniel; Burth, Sina; Windschuh, Johannes; Meissner, Jan-Eric; Zaiss, Moritz; Eidel, Oliver; Kickingereder, Philipp; Nowosielski, Martha; Wiestler, Benedikt; Sahm, Felix; Floca, Ralf Omar; Neumann, Jan-Oliver; Wick, Wolfgang; Heiland, Sabine; Bendszus, Martin; Schlemmer, Heinz-Peter; Ladd, Mark Edward; Bachert, Peter; Radbruch, Alexander

2015-01-01

To explore the correlation between Nuclear Overhauser Enhancement (NOE)-mediated signals and tumor cellularity in glioblastoma utilizing the apparent diffusion coefficient (ADC) and cell density from histologic specimens. NOE is one type of chemical exchange saturation transfer (CEST) that originates from mobile macromolecules such as proteins and might be associated with tumor cellularity via altered protein synthesis in proliferating cells. For 15 patients with newly diagnosed glioblastoma, NOE-mediated CEST-contrast was acquired at 7 Tesla (asymmetric magnetization transfer ratio (MTRasym) at 3.3ppm, B1 = 0.7 μT). Contrast enhanced T1 (CE-T1), T2 and diffusion-weighted MRI (DWI) were acquired at 3 Tesla and coregistered. The T2 edema and the CE-T1 tumor were segmented. ADC and MTRasym values within both regions of interest were correlated voxelwise yielding the correlation coefficient rSpearman (rSp). In three patients who underwent stereotactic biopsy, cell density of 12 specimens per patient was correlated with corresponding MTRasym and ADC values of the biopsy site. Eight of 15 patients showed a weak or moderate positive correlation of MTRasym and ADC within the T2 edema (0.16≤rSp≤0.53, p<0.05). Seven correlations were statistically insignificant (p>0.05, n = 4) or yielded rSp≈0 (p<0.05, n = 3). No trend towards a correlation between MTRasym and ADC was found in CE-T1 tumor (-0.310.05, n = 6). The biopsy-analysis within CE-T1 tumor revealed a strong positive correlation between tumor cellularity and MTRasym values in two of the three patients (rSppatient3 = 0.69 and rSppatient15 = 0.87, p<0.05), while the correlation of ADC and cellularity was heterogeneous (rSppatient3 = 0.545 (p = 0.067), rSppatient4 = -0.021 (p = 0.948), rSppatient15 = -0.755 (p = 0.005)). NOE-imaging is a new contrast promising insight into pathophysiologic processes in glioblastoma regarding cell density and protein content, setting itself apart from
Gene interference regulates aquaporin-4 expression in swollen tissue of rats with cerebral ischemic edema: Correlation with variation in apparent diffusion coefficient.

PubMed

Hu, Hui; Lu, Hong; He, Zhanping; Han, Xiangjun; Chen, Jing; Tu, Rong

2012-07-25

To investigate the effects of mRNA interference on aquaporin-4 expression in swollen tissue of rats with ischemic cerebral edema, and diagnose the significance of diffusion-weighted MRI, we injected 5 μL shRNA- aquaporin-4 (control group) or siRNA- aquaporin-4 solution (1:800) (RNA interference group) into the rat right basal ganglia immediately before occlusion of the middle cerebral artery. At 0.25 hours after occlusion of the middle cerebral artery, diffusion-weighted MRI displayed a high signal; within 2 hours, the relative apparent diffusion coefficient decreased markedly, aquaporin-4 expression increased rapidly, and intracellular edema was obviously aggravated; at 4 and 6 hours, the relative apparent diffusion coefficient slowly returned to control levels, aquaporin-4 expression slightly increased, and angioedema was observed. In the RNA interference group, during 0.25-6 hours after injection of siRNA- aquaporin-4 solution, the relative apparent diffusion coefficient slightly fluctuated and aquaporin-4 expression was upregulated; during 0.5-4 hours, the relative apparent diffusion coefficient was significantly higher, while aquaporin-4 expression was significantly lower when compared with the control group, and intracellular edema was markedly reduced; at 0.25 and 6 hours, the relative apparent diffusion coefficient and aquaporin-4 expression were similar when compared with the control group; obvious angioedema remained at 6 hours. Pearson's correlation test results showed that aquaporin-4 expression was negatively correlated with the apparent diffusion coefficient (r = -0.806, P < 0.01). These findings suggest that upregulated aquaporin-4 expression is likely to be the main molecular mechanism of intracellular edema and may be the molecular basis for decreased relative apparent diffusion coefficient. Aquaporin-4 gene interference can effectively inhibit the upregulation of aquaporin-4 expression during the stage of intracellular edema with time
The Swedish Exercise Self-Efficacy Scale (ESES-S): reliability and validity in a rheumatoid arthritis population.

PubMed

Nessen, Thomas; Demmelmaier, Ingrid; Nordgren, Birgitta; Opava, Christina H

2015-01-01

The aim of the present study was to investigate aspects of reliability and validity of the Exercise Self-Efficacy Scale (ESES-S) in a rheumatoid arthritis (RA) population. A total of 244 people with RA participating in a physical activity study were included. The six-item ESES-S, exploring confidence in performing exercise, was assessed for test-retest reliability over 4-6 months, and for internal consistency. Construct validity investigated correlation with similar and other constructs. An intraclass correlation coefficient (ICC) of 0.59 (95% CI 0.37-0.73) was found for 84 participants with stable health perceptions between measurement occasions. Cronbach's alpha coefficients of 0.87 and 0.89 were found at the first and second measurements. Corrected item-total correlation single ESES-S items ranged between 0.53 and 0.73. Construct convergent validity for the ESES-S was partly confirmed by correlations with health-enhancing physical activity and outcome expectations respectively (Pearson's r = 0.18, p < 0.01). Construct divergent validity was confirmed by the absence of correlations with age or gender. No floor or ceiling effects were found for ESES-S. The results indicate that the ESES-S has moderate test-retest reliability and respectable internal consistency in people with RA. Construct validity was partially supported in the present sample. Further research on construct validity of the ESES-S is recommended. Physical exercise is crucial for management of symptoms and co-morbidity in rheumatoid arthritis. Self-efficacy for exercise is important to address in rehabilitation as it regulates exercise motivation and behavior. Measurement properties of self-efficacy scales need to be assessed in specific populations and different languages.
Validation of a simplified food frequency questionnaire for the assessment of dietary habits in Iranian adults: Isfahan Healthy Heart Program, Iran.

PubMed

Mohammadifard, Noushin; Sajjadi, Firouzeh; Maghroun, Maryam; Alikhasi, Hassan; Nilforoushzadeh, Farzaneh; Sarrafzadegan, Nizal

2015-03-01

Dietary assessment is the first step of dietary modification in community-based interventional programs. This study was performed to validate a simple food frequency questionnaire (SFFQ) for assessment of selected food items in epidemiological studies with a large sample size as well as community trails. This validation study was carried out on 264 healthy adults aged ≥ 41 years old living in 3 district central of Iran, including Isfahan, Najafabad, and Arak. Selected food intakes were assessed using a 48-item food frequency questionnaire (FFQ). The FFQ was interviewer-administered, which was completed twice; at the beginning of the study and 2 weeks thereafter. The validity of this SFFQ was examined compared to estimated amount by single 24 h dietary recall and 2 days dietary record. Validation of the FFQ was determined using Spearman correlation coefficients between daily frequency consumption of food groups as assessed by the FFQ and the qualitative amount of daily food groups intake accessed by dietary reference method was applied to evaluate validity. Intraclass correlation coefficients (ICC) were used to determine the reproducibility. Spearman correlation coefficient between the estimated amount of food groups intake by examined and reference methods ranged from 0.105 (P = 0.378) in pickles to 0.48 (P < 0.001) in plant protein. ICC for reproducibility of FFQ were between 0.47-0.69 in different food groups (P < 0.001). The designed SFFQ has a good relative validity and reproducibility for assessment of selected food groups intake. Thus, it can serve as a valid tool in epidemiological studies and clinical trial with large participants.
Translation, cultural adaptation and validation into portuguese (Brazil) in Systemic Sclerosis Questionnaire (SySQ).

PubMed

Machado, Roberta Ismael Lacerda; Souto, Lais Medeiros; Freire, Eutilia Andrade Medeiros

2014-01-01

Systemic sclerosis (SSc) is a multisystem disease, autoimmune disorder characterized by a fibroblastic disfunction, with significant impact on quality of life (QoL), measured by instruments or questionnaires that usually were formulated in other languages and in different cultural contexts. Translate into Brazilian Portuguese, cross cultural adaptation and assess the reliability and validity of the Systemic Sclerosis Questionnaire (SySQ). Translation and adaptation: into Portuguese and cross-cultural adaptation was performed in accordance with studies on questionnaire translation methodology into other languages. Reliability: it was analyzed using three interviews with different interviewers, two on the same day (interobserver) and the third within 14 days of the first assessment (intraobserver).Validity was assessed by correlating clinical and quality of life parameters with the domain scores of Sysc. a descriptive analysis of the study sample. Reproducibility was assessed using an intraclass correlation coefficient (ICC). Internal consistency was assessed using Cronbach's alpha coefficient. To assess validity we used Spearman correlation coefficient. Five percent was the level of significance adopted for all statistical tests. In the evaluation of the questionnaires, the results were similar to the original questionnaire, the internal consistency ranging between 0.73 and 0.93 for each item. The interobserver reproducibility was very good for all domains (α = 0.786 to 0.983) and intraobserver agreement was considered very good for general symptoms domain (ICC = 0.916), good for musculoskeletal symptoms domain (ICC = 0.897) and cardiopulmonary domain (ICC = 0.842) and reasonable for gastrointestinal symptoms domain (ICC = 0.686). The Brazilian Portuguese version of SySQ proved to be reproducible and valid for our population, using a recognized methodology for translation and cultural adaptation of questionnaires, as well as to assess the reproducibility and
Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-05-29

Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Methodological and cross sectional study. A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain.
Validity and reliability of head posture measurement using Microsoft Kinect.

PubMed

Oh, Baek-Lok; Kim, Jongmin; Kim, Jongshin; Hwang, Jeong-Min; Lee, Jehee

2014-11-01

To investigate the validity and reliability of Microsoft Kinect-based head tracker (KHT) for measuring head posture. Considering the cervical range of motion (CROM) as a reference, one-dimensional and three-dimensional (1D and 3D) head postures of 12 normal subjects (28-58 years of age; 6 women and 6 men) were obtained using the KHT. The KHT was validated by Pearson's correlation coefficient and intraclass correlation (ICC) coefficient. Test-retest reliability of the KHT was determined by its 95% limit of agreement (LoA) with the Bland-Altman plot. Face recognition success rate was evaluated for each head posture. Measurements of 1D and 3D head posture performed using the KHT were very close to those of the CROM with correlation coefficients of 0.99 and 0.97 (p<0.05), respectively, as well as with an ICC of >0.99 and 0.98, respectively. The reliability tests of the KHT in terms of 1D and 3D head postures had 95% LoA angles of approximately ±2.5° and ±6.5°, respectively. The KHT showed good agreement with the CROM and relatively favourable test-retest reliability. Considering its high performance, convenience and low cost, KHT could be clinically used as a head posture-measuring system. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Adaptation and validation of the Spanish version of the Actinic Keratosis Quality of Life questionnaire.

PubMed

Longo Imedio, Isabel; Serra-Guillén, Carlos

2016-01-01

While there are questionnaires for evaluating the effects of skin cancer on patient quality of life, there are no specific questionnaires available in Spanish for evaluating quality of life in patients with actinic keratosis. The aim of this study was to translate and culturally adapt the Actinic Keratosis Quality of Life (AKQoL) questionnaire into Spanish. The original questionnaire was translated into Spanish following the guidelines for the cross-cultural adaptation of self-report measures. Several measures of general reliability and validity were calculated, including Cronbach α for internal consistency and the Spearman rank-order correlation coefficient and a Bland-Altman plot for test-retest reliability. To test concurrent validity, we used the Pearson correlation coefficient to measure the correlation between AKQoL and Skindex-29 scores. The final version of the questionnaire was administered to 621 patients with actinic keratosis, who scored a mean (SD) of 5.25 (4.73) points (total possible score, 0-25). The Cronbach α reliability coefficient analysis was 0.84. The correlation between the mean (SD) score on the Skindex-29 (1.87 [4.07]) and on the AKQoL (1.97 [2.98] was 0.344 (P=.002, Spearman's rho), with a proportion of shared variance of 11.8%. The translation, cross-cultural adaptation, and validation of the original AKQoL produced a reliable, easily understandable questionnaire for evaluating the impact of actinic keratosis on the quality of life of patients in our setting. Copyright © 2016 AEDV. Published by Elsevier España, S.L.U. All rights reserved.
Momentum, sensible heat and CO2 correlation coefficient variability: what can we learn from 20 years of continuous eddy covariance measurements?

NASA Astrophysics Data System (ADS)

Hurdebise, Quentin; Heinesch, Bernard; De Ligne, Anne; Vincke, Caroline; Aubinet, Marc

2017-04-01

Long-term data series of carbon dioxide and other gas exchanges between terrestrial ecosystems and atmosphere become more and more numerous. Long-term analyses of such exchanges require a good understanding of measurement conditions during the investigated period. Independently of climate drivers, measurements may indeed be influenced by measurement conditions themselves subjected to long-term variability due to vegetation growth or set-up changes. The present research refers to the Vielsalm Terrestrial Observatory (VTO) an ICOS candidate site located in a mixed forest (beech, silver fir, Douglas fir, Norway spruce) in the Belgian Ardenne. Fluxes of momentum, carbon dioxide and sensible heat have been continuously measured there by eddy covariance for more than 20 years. During this period, changes in canopy height and measurement height occurred. The correlation coefficients (for momemtum, sensible heat and CO2) and the normalized standard deviations measured for the past 20 years at the Vielsalm Terrestrial Observatory (VTO) were analysed in order to define how the fluxes, independently of climate conditions, were affected by the surrounding environment evolution, including tree growth, forest thinning and tower height change. A relationship between canopy aerodynamic distance and the momentum correlation coefficient was found which is characteristic of the roughness sublayer, and suggests that momentum transport processes were affected by z-d. In contrast, no relationship was found for sensible heat and CO2 correlation coefficients, suggesting that the z-d variability observed did not affect their turbulent transport. There were strong differences in these coefficients, however, between two wind sectors, characterized by contrasted stands (height differences, homogeneity) and different hypotheses were raised to explain it. This study highlighted the importance of taking the surrounding environment variability into account in order to ensure the spatio
Psychometric Validation of the Korean Version of the Camberwell Assessment of Need for the Elderly (CANE-K) in Dementia.

PubMed

Park, Myonghwa; Kyung Kim, Sun; Jeong, Miri; Lee, Song Ja; Kim, Seon Hwa; Kim, Jinha; Lee, Dong Young

2018-04-10

The prevalence of dementia has increased rapidly with an aging Korean population. Compared to those without dementia, individuals with dementia have more and complex needs. In this study, the Korean version of the Camberwell Assessment of Need for the Elderly (CANE-K) was evaluated to determine its suitability for individuals with dementia in Korea. The CANE-K was developed following linguistic validation. The reliability of the measurement was examined with Cronbach's alpha coefficient. The factor structure and construct validity were evaluated by performing exploratory factor analysis (EFA) and confirmatory factor analyses (CFA). Pearson's correlation coefficients with related measures were used to ensure concurrent validity. Four factors extracted with EFA and CFA validated the model structure (X 2 = 367.25, p = .000, goodness of fit index = .84, adjusted goodness of fit index = .80, root mean square error of approximation = .07, and comparative fit index = .83). Items on the CANE-K loaded on the four factors in a range between .40 and .80. The output of Pearson's correlation coefficient with cognitive impairment, behavioral problems, activities of daily living and caregiver burden showed acceptable concurrent validity. The CANE-K showed a reasonable degree of reliability and validity. Therefore, it has good potential to appropriately measure the needs and unmet needs of those with dementia. Copyright © 2018. Published by Elsevier B.V.
Reliability and validity analysis of the transfer assessment instrument.

PubMed

McClure, Laura A; Boninger, Michael L; Ozawa, Haishin; Koontz, Alicia

2011-03-01

To describe the development and evaluate the reliability and validity of a newly created outcome measure, the Transfer Assessment Instrument (TAI), to assess the quality of transfers performed by full-time wheelchair users. Repeated measures. 2009 National Veterans Wheelchair Games in Spokane, WA. A convenience sample of full-time wheelchair users (N=40) who perform sitting pivot or standing pivot transfers. Not applicable. Intraclass correlation coefficients (ICCs) for reliability and Spearman correlation coefficients for concurrent validity between the TAI and a global assessment scale (0-100 visual analog scale [VAS]). No adverse events occurred during testing. Intrarater ICCs for 3 raters ranged between .35 and .89, and the interrater ICC was .642. Correlations between the TAI and a global assessment VAS ranged between .19 (P=.285) and .69 (P>.000). Item analyses of the tool found a wide range of results, from weak to good reliability. Evaluators found the TAI to be safe and able to be completed in a short time. The TAI is a safe, quick outcome measure that uses equipment typically found in a clinical setting and does not ask participants to perform new skills. Reliability and validity testing found the TAI to have acceptable interrater and a wide range of intrarater reliability. Future work indicates the need for continued refinement including removal or modification of items found to have low reliability, improved education for clinicians, and further reliability and validity analysis with a more diverse subject population. The TAI has the potential to fill a void in assessment of transfers. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.
Validation of the Japanese Society for Surgery of the Hand version of the Carpal Tunnel Syndrome Instrument.

PubMed

Imaeda, Toshihiko; Uchiyama, Shigeharu; Toh, Satoshi; Wada, Takuro; Okinaga, Shuji; Sawaizumi, Takuya; Nishida, Jun; Kusunose, Koichi; Omokawa, Shohei

2007-01-01

The Carpal Tunnel Syndrome Instrument (CTSI) is a disease-specific, self-administered questionnaire that consists of a symptom severity scale (SS) and a functional status scale (FS). The CTSI was cross-culturally adapted and developed by the Impairment Evaluation Committee, Japanese Society for Surgery of the Hand (JSSH). The purpose of this study was to test the reliability, validity, and responsiveness of the Japanese version of the CTSI (CTSI-JSSH). A consecutive series of 87 patients with carpal tunnel syndrome completed the CTSI-JSSH, the JSSH version of the Disability of the Arm, Shoulder, and Hand questionnaire (DASH-JSSH), and the 36-Item Short-Form Health Survey (SF-36). Seventy-two of the patients were reassessed for test-retest reliability 1 or 2 weeks later. Reliability was investigated by the reproducibility and the internal consistency. To analyze the validity, a factor analysis (principal axis factoring) of the CTSI-JSSH and the correlation coefficients between the CTSI-JSSH and DASH-JSSH were obtained. The responsiveness was examined by calculating the standardized response mean (SRM; mean change/SD) and effect size (mean change/SD of baseline value) after carpal tunnel release in 42 patients. Cronbach's alpha coefficients for the CTSI-JSSH-SS and the CTSI-JSSH-FS were 0.84 and 0.90, respectively, and the intraclass correlation coefficients were 0.82 and 0.83, respectively. The unidimensionality of the CTSI-JSSH-SS was barely confirmed; the unidimensionality of the CTSI-JSSH-FS was confirmed. The correlation coefficients between the CTSI-JSSH-FS and the CTSI-JSSH-SS or DASH-JSSH were 0.58 and 0.80, respectively. The correlation coefficient between the CTSI-JSSH-SS and DASH-JSSH was 0.54. The correlation coefficients between the subscales of SF-36 and the CTSI-JSSH-SS or the CTSI-JSSH-FS ranged from -0.23 to -0.66 and from -0.19 to -0.63, respectively. The SRMs/effect sizes of the CTSI-JSSH-SS and the CTSI-JSSH-FS were -0.85/-0.99 and -0
Validation of the Chinese version of EORTC QLQ-BN20 for patients with brain cancer.

PubMed

Zhang, K; Tian, J; He, Z; Sun, W; Pekbay, B; Lin, Y; Wu, D; Zhang, J; Chen, P; Guo, H; Wan, Y; Wang, M; Yang, S; Zheng, J; Zhang, L

2018-03-01

This is a single centre study in mainland China aiming to evaluate the reliability, validity and responsiveness of the Chinese version of EORTC QLQ-BN20, designed by The European Organization for Research and Treatment of Cancer Quality of Life Group to evaluate the life quality of patients with brain tumour, cancer or metastases. One hundred and eighty-eight patients with primary or secondary brain cancer from Hunan Provincial Tumor Hospital during September 2013 to June 2014 completed the Chinese EORTC QLQ-C30/BN20 questionnaires developed by translation, back translation and cultural adaptation. Results were statistically analysed using SPSS17.0. The internal consistency (Cronbach's α coefficient) was between .753 and .869, the correlation coefficients among items and its own dimension were bigger than .4, and all items had a better correlation with its own dimension. The Spearman was used to analyse the correlation of each dimension between EORTC QLQ-BN20 and EORTC QLQ-C30, and the result showed that individual dimensions were moderately correlated, other dimensions were weakly correlated. In conclusion, the Chinese version of EORTC QLQ BN20 questionnaire had great relevance, reliability, convergent validity and discriminant validity. It provides a valuable tool for the assessment of health-related quality of life in clinical studies of Chinese patients with primary or secondary brain cancer. © 2018 John Wiley & Sons Ltd.
Validity and reliability of a self-report instrument to assess social support and physical environmental correlates of physical activity in adolescents.

PubMed

Reimers, Anne K; Jekauc, Darko; Mess, Filip; Mewes, Nadine; Woll, Alexander

2012-08-29

The purpose of this study was to examine the internal consistency, test-retest reliability, construct validity and predictive validity of a new German self-report instrument to assess the influence of social support and the physical environment on physical activity in adolescents. Based on theoretical consideration, the short scales on social support and physical environment were developed and cross-validated in two independent study samples of 9 to 17 year-old girls and boys. The longitudinal sample of Study I (n = 196) was recruited from a German comprehensive school, and subjects in this study completed the questionnaire twice with a between-test interval of seven days. Cronbach's alphas were computed to determine the internal consistency of the factors. Test-retest reliability of the latent factors was assessed using intra-class coefficients. Factorial validity of the scales was assessed using principle components analysis. Construct validity was determined using a cross-validation technique by performing confirmatory factor analysis with the independent nationwide cross-sectional sample of Study II (n = 430). Correlations between factors and three measures of physical activity (objectively measured moderate-to-vigorous physical activity (MVPA), self-reported habitual MVPA and self-reported recent MVPA) were calculated to determine the predictive validity of the instrument. Construct validity of the social support scale (two factors: parental support and peer support) and the physical environment scale (four factors: convenience, public recreation facilities, safety and private sport providers) was shown. Both scales had moderate test-retest reliability. The factors of the social support scale also had good internal consistency and predictive validity. Internal consistency and predictive validity of the physical environment scale were low to acceptable. The results of this study indicate moderate to good reliability and construct validity of the
Reliable and valid assessment of Lichtenstein hernia repair skills.

PubMed

Carlsen, C G; Lindorff-Larsen, K; Funch-Jensen, P; Lund, L; Charles, P; Konge, L

2014-08-01

Lichtenstein hernia repair is a common surgical procedure and one of the first procedures performed by a surgical trainee. However, formal assessment tools developed for this procedure are few and sparsely validated. The aim of this study was to determine the reliability and validity of an assessment tool designed to measure surgical skills in Lichtenstein hernia repair. Key issues were identified through a focus group interview. On this basis, an assessment tool with eight items was designed. Ten surgeons and surgical trainees were video recorded while performing Lichtenstein hernia repair, (four experts, three intermediates, and three novices). The videos were blindly and individually assessed by three raters (surgical consultants) using the assessment tool. Based on these assessments, validity and reliability were explored. The internal consistency of the items was high (Cronbach's alpha = 0.97). The inter-rater reliability was very good with an intra-class correlation coefficient (ICC) = 0.93. Generalizability analysis showed a coefficient above 0.8 even with one rater. The coefficient improved to 0.92 if three raters were used. One-way analysis of variance found a significant difference between the three groups which indicates construct validity, p < 0.001. Lichtenstein hernia repair skills can be assessed blindly by a single rater in a reliable and valid fashion with the new procedure-specific assessment tool. We recommend this tool for future assessment of trainees performing Lichtenstein hernia repair to ensure that the objectives of competency-based surgical training are met.
Validity and Reliability of the Golombok Rust Inventory of Sexual Satisfaction in Couples with Incontinent Partners.

PubMed

Lim, Renly; Liong, Men Long; Khan, Nurzalina Abdul Karim; Yuen, Kah Hay

2017-02-17

There is currently no published information on the validity and reliability of the Golombok Rust Inventory of Sexual Satisfaction in the Asian population, specifically in patients with stress urinary incontinence, which limits its use in this region. Our study aimed to evaluate the psychometric properties of this questionnaire in the Malaysian population. Ten couples were recruited for the pilot testing. The agreement between the English and Chinese or Malay versions were tested using the intraclass correlation coefficients, with results of more than 0.80 for all subscales and overall scores indicating good agreement. Sixty-six couples were included in the subsequent phase. The following data are presented in the order of English, Chinese, and Malay. Cronbach's alphas for the male total score were 0.82, 0.88, and 0.95. For the female total score, Cronbach's alphas were 0.76, 0.78, and 0.88. Intraclass correlation coefficients for the male total score were 0.93, 0.94, and 0.99, while intraclass correlation coefficients for the female total score were 0.89, 0.86, and 0.88. In conclusion, the English, Chinese, and Malay versions each proved to be valid and reliable in our Malaysian population.

The Effect of a Fluorophore Photo-Physics on the Lipid Vesicle Diffusion Coefficient Studied by Fluorescence Correlation Spectroscopy.

PubMed

Drabik, Dominik; Przybyło, Magda; Sikorski, Aleksander; Langner, Marek

2016-03-01

Fluorescence Correlation Spectroscopy (FCS) is a technique, which allows determination of the diffusion coefficient and concentration of fluorescent objects suspended in the solution. The measured parameter is the fluctuation of the fluorescence signal emitted by diffusing molecules. When 100 nm DOPC vesicles labeled with various fluorescent dyes (Fluorescein-PE, NBD-PE, Atto488 DOPE or βBodipy FL) were measured, different values of diffusion coefficients have been obtained. These diffusion coefficients were different from the expected values measured using the dynamic light scattering method (DLS). The FCS was initially developed for solutions containing small fluorescent molecules therefore the observed inconsistency may result from the nature of vesicle suspension itself. The duration of the fluorescence signal may depend on the following factors: the exposure time of the labeled object to the excitation beam, the photo-physical properties (e.g., stability) of a fluorophore, the theoretical model used for the calculations of the diffusion coefficient and optical properties of the vesicle suspension. The diffusion coefficients determined for differently labeled liposomes show that its dependence on vesicle size and quantity of fluorescent probed used for labeling was significant demonstrating that the fluorescence properties of the fluorophore itself (bleaching and/or blinking) were critical factors for a correct outcome of FCS experiment. The new, based on combined FCS and DLS measurements, method for the determination of the focal volume prove itself to be useful for the evaluation of a fluorescence dye with respect to its applicability for FCS experiment.
Creation and Validation of the Self-esteem/Self-image Female Sexuality (SESIFS) Questionnaire

PubMed Central

Lordello, Maria CO; Ambrogini, Carolina C; Fanganiello, Ana L; Embiruçu, Teresa R; Zaneti, Marina M; Veloso, Laise; Piccirillo, Livia B; Crude, Bianca L; Haidar, Mauro; Silva, Ivaldo

2014-01-01

INTRODUCTION Self-esteem and self-image are psychological aspects that affect sexual function. AIMS To validate a new measurement tool that correlates the concepts of self-esteem, self-image, and sexuality. METHODS A 20-question test (the self-esteem/self-image female sexuality [SESIFS] questionnaire) was created and tested on 208 women. Participants answered: Rosenberg’s self-esteem scale, the female sexual quotient (FSQ), and the SESIFS questionnaire. Pearson’s correlation coefficient was used to test concurrent validity of the SESIFS against Rosenberg’s self-esteem scale and the FSQ. Reliability was tested using the Cronbach’s alpha coefficient. RESULT The new questionnaire had a good overall reliability (Cronbach’s alpha r = 0.862, p < 0.001), but the sexual domain scored lower than expected (r = 0.65). The validity was good: overall score r = 0.38, p < 0.001, self-esteem domain r = 0.32, p < 0.001, self-image domain r = 0.31, p < 0.001, sexual domain r = 0.29, p < 0.001. CONCLUSIONS The SESIFS questionnaire has limitations in measuring the correlation among self-esteem, self-image, and sexuality domains. A new, revised version is being tested and will be presented in an upcoming publication. PMID:25574149
Performance of intraclass correlation coefficient (ICC) as a reliability index under various distributions in scale reliability studies.

PubMed

Mehta, Shraddha; Bastero-Caballero, Rowena F; Sun, Yijun; Zhu, Ray; Murphy, Diane K; Hardas, Bhushan; Koch, Gary

2018-04-29

Many published scale validation studies determine inter-rater reliability using the intra-class correlation coefficient (ICC). However, the use of this statistic must consider its advantages, limitations, and applicability. This paper evaluates how interaction of subject distribution, sample size, and levels of rater disagreement affects ICC and provides an approach for obtaining relevant ICC estimates under suboptimal conditions. Simulation results suggest that for a fixed number of subjects, ICC from the convex distribution is smaller than ICC for the uniform distribution, which in turn is smaller than ICC for the concave distribution. The variance component estimates also show that the dissimilarity of ICC among distributions is attributed to the study design (ie, distribution of subjects) component of subject variability and not the scale quality component of rater error variability. The dependency of ICC on the distribution of subjects makes it difficult to compare results across reliability studies. Hence, it is proposed that reliability studies should be designed using a uniform distribution of subjects because of the standardization it provides for representing objective disagreement. In the absence of uniform distribution, a sampling method is proposed to reduce the non-uniformity. In addition, as expected, high levels of disagreement result in low ICC, and when the type of distribution is fixed, any increase in the number of subjects beyond a moderately large specification such as n = 80 does not have a major impact on ICC. Copyright © 2018 John Wiley & Sons, Ltd.
Reliability and validity of quantifying absolute muscle hardness using ultrasound elastography.

PubMed

Chino, Kentaro; Akagi, Ryota; Dohi, Michiko; Fukashiro, Senshi; Takahashi, Hideyuki

2012-01-01

Muscle hardness is a mechanical property that represents transverse muscle stiffness. A quantitative method that uses ultrasound elastography for quantifying absolute human muscle hardness has been previously devised; however, its reliability and validity have not been completely verified. This study aimed to verify the reliability and validity of this quantitative method. The Young's moduli of seven tissue-mimicking materials (in vitro; Young's modulus range, 20-80 kPa; increments of 10 kPa) and the human medial gastrocnemius muscle (in vivo) were quantified using ultrasound elastography. On the basis of the strain/Young's modulus ratio of two reference materials, one hard and one soft (Young's moduli of 7 and 30 kPa, respectively), the Young's moduli of the tissue-mimicking materials and medial gastrocnemius muscle were calculated. The intra- and inter-investigator reliability of the method was confirmed on the basis of acceptably low coefficient of variations (≤6.9%) and substantially high intraclass correlation coefficients (≥0.77) obtained from all measurements. The correlation coefficient between the Young's moduli of the tissue-mimicking materials obtained using a mechanical method and ultrasound elastography was 0.996, which was equivalent to values previously obtained using magnetic resonance elastography. The Young's moduli of the medial gastrocnemius muscle obtained using ultrasound elastography were within the range of values previously obtained using magnetic resonance elastography. The reliability and validity of the quantitative method for measuring absolute muscle hardness using ultrasound elastography were thus verified.
Reliability and validity of a questionnaire for self-assessment of complete dentures.

PubMed

Komagamine, Yuriko; Kanazawa, Manabu; Kaiba, Yoshinori; Sato, Yusuke; Minakuchi, Shunsuke

2014-05-02

Demand for complete denture treatment is expected to rise over several decades. However, to date, no questionnaire on complete dentures, as evaluated by edentulous patients, has been shown to be reliable and valid. This study sought to assess the reliability and validity of Patient's Denture Assessment (PDA), which provides a multidimensional evaluation of dentures among edentulous patients. Patients, who had new complete dentures fabricated at the University Hospital of Dentistry, Tokyo Medical and Dental University through 2009 to 2010, were enrolled. The reliability of the PDA was determined by examining internal consistency and test-retest reliability. Internal consistency for all of the question items and the six subscales was measured using Cronbach's α and average inter-item correlation coefficients among 93 participants. For 33 of these participants, test-retest reliability was determined at a 2 month-interval using the interclass correlation coefficients (ICCs) and 95% confidence interval for the summary scores and the six subscale scores. The PDA was validated in 93 participants by examining the difference in the summary score and the six subscale scores of the PDA before and after replacement with new dentures by the paired t-test. Ability to detect change was also tested in 93 patients using effect size. The Cronbach's α for the PDA ranged from 0.56 to 0.93. The average inter-item correlation coefficients ranged from 0.28 to 0.83. ICCs for the PDA ranged from 0.37 to 0.83. The paired t-test showed a significant difference between the summary score and the six subscale scores before and after replacement with new dentures (p < 0.05) and the effect size was 0.97. The PDA demonstrated good reliability by assessing internal consistency and test-retest reliability. In addition, the PDA demonstrated good validity by assessing discriminant validity. Thus, the PDA could help dentists obtain a detailed understanding of the patients' perceptions in using
Validity and reliability of the Turkish version of the European Health Literacy Survey Questionnaire.

PubMed

Abacigil, Filiz; Harlak, Hacer; Okyay, Pinar; Kiraz, Didem Evci; Gursoy Turan, Selen; Saruhan, Gulnur; Karakaya, Kagan; Tuzun, Hakan; Baran Deniz, Emine; Tontus, Omer; Beser, Erdal

2018-04-10

Health literacy is a public health priority which refers to individual's knowledge, motivation and competence to access, understand, appraise and apply health information to prevent disease and promote health in daily life. This study aimed to adapt European Health Literacy Survey Questionnaire (HLS-EU-Q47) into Turkish and to investigate its psychometric properties. The questionnaire was translated into Turkish by using both group translation and expert opinion methods. Forward translation-back translation method was used for language validity and the final Turkish version (HLS-TR) was formed. HLS-EU-Q47 and Health Awareness Scale (HAS) were administered to 505 respondents. The scale reliability was examined using Crohnbach's alpha coefficient and the construct validity was assessed by principal axis factoring procedure. The convergent validity was obtained by Pearson correlation coefficients between HLS-TR and HAS scores and discriminant validity was examined comparing the scores of participants who were stratified according to ages, educational status, gender, general health status and social status. Cronbach's alpha coefficient for the whole scale was 0.95. Principal axis factoring extracted nine factors which eigenvalues were >1 and explained 50.01% of total variance. Factor matrix displayed that all items gave greater load in factor 1, showing that health literacy measured with one factor. Positive and significant correlation was found between HLS-TR and HAS. Significant relations were found between HLS-TR scores and selected determinants of health. This study revealed that the HLS-TR was a valid and reliable measuring instrument with appropriate psychometric characteristics.
Validation of the Spanish version of the WOMAC questionnaire for patients with hip or knee osteoarthritis. Western Ontario and McMaster Universities Osteoarthritis Index.

PubMed

Escobar, A; Quintana, J M; Bilbao, A; Azkárate, J; Güenaga, J I

2002-11-01

The aim of this study was to validate a translated version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire in Spanish patients with hip or knee osteoarthritis (OA). The WOMAC questionnaire and the SF-36 were administered to a sample of 269 patients on the waiting list for hip or knee replacement. We studied the convergent validity and the item-scale correlation using Pearson's correlation coefficient and Spearman's pi. For the reliability study we used another sample of 58 patients who received the WOMAC twice within 15 days. The Pearson's, Spearman's pi, and intraclass correlation coefficients were calculated. Internal consistency was measured by Cronbach's alpha. The responsiveness study was carried out by resending the two questionnaires to all patients 6 months after surgical intervention; responsiveness was measured by means of the paired t-test, the effect size I and the standardised response mean. The Pearson's coefficients for the convergent validity ranged from -0.52 to -0.63. The coefficients obtained for the item-scale correlation of the pain area were 0.74 or higher, 0.91 or higher for stiffness, and 0.61 or higher for function. When measuring the test-retest reliability, the coefficients ranged from 0.66 to 0.81. Internal consistency yielded a Cronbach's alpha ranging from 0.81 to 0.93. The responsiveness showed an effect size I ranging from 1.5 to 2.2 in patients who underwent hip replacement; for those who underwent knee replacement the range was 1 to 1.8. The standardised response mean ranged from 1.3 to 1.9 for patients with hip OA; those with knee OA ranged from 0.8 to 1.5. The Spanish version of WOMAC is a valid, reliable and responsive instrument in patients with hip or knee OA.
Reliability, validity, and responsiveness of the Japanese version of the Patient-Rated Wrist Evaluation.

PubMed

Imaeda, Toshihiko; Uchiyama, Shigeharu; Wada, Takuro; Okinaga, Shuji; Sawaizumi, Takuya; Omokawa, Shohei; Momose, Toshimitsu; Moritomo, Hisao; Gotani, Hiroyuki; Abe, Yukio; Nishida, Jun; Kanaya, Fuminori

2010-07-01

The Patient-Rated Wrist Evaluation is a regionspecific, self-administered questionnaire consisting of a pain scale (PRWE-P) and a functional scale (PRWE-F), with the latter consisting of specific function (PRWE-SF) and usual function (PRWE-UF). The PRWE was cross-culturally adapted from the original English version by the Impairment Evaluation Committee, Japanese Society for Surgery of the Hand (JSSH). The purpose of this study was to test the reliability, validity, and responsiveness of the Japanese version of PRWE (PRWE-J). A consecutive series of 117 patients with wrist disorders completed the PRWE-J, the JSSH version of the Disabilities of the Arm, Shoulder, and Hand (DASH-JSSH) questionnaire and the 36-Item Short-Form Health Survey (SF-36). Of the 117 patients, 71 were reassessed for test-retest reliability 1 or 2 weeks later. Reliability was investigated by reproducibility and internal consistency. To analyze the validity, a factor analysis (principal axis factoring) of PRWE-J and correlation coefficients between PRWE-J and DASH-JSSH were obtained. Responsiveness was examined by calculating the standardized response mean (SRM) (mean change/SD) and effect size (mean change/SD of baseline value) after open surgery in 50 patients. Cronbach's alpha coefficients for PRWE-P, PRWE-F, and PRWE were 0.90, 0.95, and 0.95, respectively. The intraclass correlation coefficients (ICCs) for the same were 0.86, 0.93, and 0.92, respectively. Unidimensionality of PRWE-P was con-firmed. Bidimensionality of PRWE-F was confirmed and separated clearly into PRWE-SF and PRWE-UF. The correlation coefficients between PRWE-P and PRWE-F or DASH-JSSH were 0.63 or 0.63, respectively. The correlation coefficient between PRWE-F and DASH-JSSH was 0.80. The correlation coefficients between DASH-JSSH and PRWE-SF or PRWE-UF were 0.76 or 0.73, respectively. Moderate correlation was observed in "physical functioning" for SF-36 and PRWE-SF (r = -0.46), PRWE-F (r = -0.46), or PRWE (r = -0.46). The
Reliability and validity of the Chinese version of the autoimmune bullous disease quality of life (ABQOL) questionnaire.

PubMed

Yang, Baoqi; Chen, Guo; Yang, Qing; Yan, Xiaoxiao; Zhang, Zhaoxia; Murrell, Dédée F; Zhang, Furen

2017-02-02

The autoimmune bullous diseases quality of life (ABQOL) questionnaire was recently developed by an Australian group and has been validated in Australian and North American patient cohorts. It is a 17-item, multidimensional, self-administered English questionnaire. The study aimed to validate the Chinese version of the ABQOL questionnaire and evaluate the reliability in Chinese patients. The Chinese version of the ABQOL questionnaire was produced by forward-backward translation and cross-cultural adaptation of the original English version. The ABQOL questionnaire was then distributed to a total of 101 patients with autoimmune bullous diseases (AIBDs) together with the Dermatology Life Quality Index (DLQI) and the 36-item Short Form Health Survey (SF-36). Validity was analyzed across a range of indices and reliability was assessed using internal consistency and test-retest methods. The Chinese version of the ABQOL questionnaire has a high internal consistency (Cronbach's alpha coefficient, 0.88) and test-retest reliability (the intraclass correlation coefficient, 0.87). Face and content validity were satisfactory. Convergent validity testing showed that the correlation coefficients for the ABQOL and DLQI was 0.77 and for the ABQOL and SF-36 was -0.62. In terms of discriminant validity, there was no significant difference between the proportions of insensitive items in ABQOL and DLQI (p = 0.236). There was no significant difference between the proportions of insensitive items in ABQOL and SF-36 (p = 0.823). The Chinese version of the ABQOL questionnaire has adequate validity and reliability. It may constitute a useful instrument to measure disease burden in Chinese patients with AIBDs.
The reliability and validity of a short food frequency questionnaire among 9–11-year olds: a multinational study on three middle-income and high-income countries

PubMed Central

Saloheimo, T; González, S A; Erkkola, M; Milauskas, D M; Meisel, J D; Champagne, C M; Tudor-Locke, C; Sarmiento, O; Katzmarzyk, P T; Fogelholm, M

2015-01-01

Objective: The main aim of this study was to assess the reliability and validity of a food frequency questionnaire with 23 food groups (I-FFQ) among a sample of 9–11-year-old children from three different countries that differ on economical development and income distribution, and to assess differences between country sites. Furthermore, we assessed factors associated with I-FFQ's performance. Methods: This was an ancillary study of the International Study of Childhood Obesity, Lifestyle and the Environment. Reliability (n=321) and validity (n=282) components of this study had the same participants. Participation rates were 95% and 70%, respectively. Participants completed two I-FFQs with a mean interval of 4.9 weeks to assess reliability. A 3-day pre-coded food diary (PFD) was used as the reference method in the validity analyses. Wilcoxon signed-rank tests, intraclass correlation coefficients and cross-classifications were used to assess the reliability of I-FFQ. Spearman correlation coefficients, percentage difference and cross-classifications were used to assess the validity of I-FFQ. A logistic regression model was used to assess the relation of selected variables with the estimate of validity. Analyses based on information in the PFDs were performed to assess how participants interpreted food groups. Results: Reliability correlation coefficients ranged from 0.37 to 0.78 and gross misclassification for all food groups was <5%. Validity correlation coefficients were below 0.5 for 22/23 food groups, and they differed among country sites. For validity, gross misclassification was <5% for 22/23 food groups. Over- or underestimation did not appear for 19/23 food groups. Logistic regression showed that country of participation and parental education were associated (P⩽0.05) with the validity of I-FFQ. Analyses of children's interpretation of food groups suggested that the meaning of most food groups was understood by the children. Conclusion: I-FFQ is a
Test-retest reliability and validity of a web-based food-frequency questionnaire for adolescents aged 13-14 to be used in the Norwegian Mother and Child Cohort Study (MoBa).

PubMed

Overby, Nina Cecilie; Johannesen, Elisabeth; Jensen, Grete; Skjaevesland, Anne-Kirsti; Haugen, Margaretha

2014-01-01

The assessment of food intake is challenging and prone to errors; it is therefore important to consider the reliability and validity of the assessment methods. The aim of this study was to analyze the reproducibility and validity of a developed food-frequency questionnaire (FFQ) for use among adolescents. In total, 58 students (aged 13-14) from four different schools in the southern part of Norway participated in the reproducibility study of filling out the FFQ 4 weeks apart. In addition, 93 students participated in the relative validity study where the FFQ was compared to 2×24-hour dietary recalls, while 92 students participated in the absolute validity study where the intakes of fatty acids and vitamin D from the FFQ were compared to fatty acids and 25-hydroxy-vitamin D3 in whole blood. The median Spearman correlation coefficient for all nutrients in the test-retest reliability study was 0.57. The median Spearman correlation for all nutrients in the relative validity study was 0.26, while the correlations coefficients were low in the absolute validity study with n-3 fatty acid coefficients ranging from 0.05 to 0.25, and absent for vitamin D (r=0.000). The test-retest reproducibility was considered good, the relative validity was considered poor to good, and the absolute validity was considered poor. However, the results are comparable to other studies among adolescents.
Content validity and reliability of test of gross motor development in Chilean children

PubMed Central

Cano-Cappellacci, Marcelo; Leyton, Fernanda Aleitte; Carreño, Joshua Durán

2016-01-01

ABSTRACT OBJECTIVE To validate a Spanish version of the Test of Gross Motor Development (TGMD-2) for the Chilean population. METHODS Descriptive, transversal, non-experimental validity and reliability study. Four translators, three experts and 92 Chilean children, from five to 10 years, students from a primary school in Santiago, Chile, have participated. The Committee of Experts has carried out translation, back-translation and revision processes to determine the translinguistic equivalence and content validity of the test, using the content validity index in 2013. In addition, a pilot implementation was achieved to determine test reliability in Spanish, by using the intraclass correlation coefficient and Bland-Altman method. We evaluated whether the results presented significant differences by replacing the bat with a racket, using T-test. RESULTS We obtained a content validity index higher than 0.80 for language clarity and relevance of the TGMD-2 for children. There were significant differences in the object control subtest when comparing the results with bat and racket. The intraclass correlation coefficient for reliability inter-rater, intra-rater and test-retest reliability was greater than 0.80 in all cases. CONCLUSIONS The TGMD-2 has appropriate content validity to be applied in the Chilean population. The reliability of this test is within the appropriate parameters and its use could be recommended in this population after the establishment of normative data, setting a further precedent for the validation in other Latin American countries. PMID:26815160
MEASUREMENT OF THE CORRELATION COEFFICIENT Cnn AT 90 AND AN ENERGY OF 315 MEV FOR THE ELASTIC PP-SCATTERING

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vasilevskii, I.M.; Vishnyakov, V.V.; Iliescu, E.

1960-01-01

The spin correlation coefficient C/sub nn/ was measured for p-p scattering at 90 deg (c.m.s.) and 315 Mev and found to be 0.52 plus or minus 0.20. Calibration experiments on the polarization of protons at 640 Mev gave C/ sub nn/ = 0.7 plus or minus 0.3. (D.L.C.)
Translation and validation of a Nepalese version of the Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ).

PubMed

Singh, Varun Pratap; Singh, Rajkumar

2014-03-01

The aim of this study was to develop a reliable and valid Nepali version of the Psychosocial Impact of Dental Aesthetic Questionnaire (PIDAQ). Cross-sectional descriptive validation study. B.P. Koirala Institute of Health Sciences, Dharan, Nepal. A rigorous translation process including conceptual and semantic evaluation, translation, back translation and pre-testing was carried out. Two hundred and fifty-two undergraduates, including equal numbers of males and females with an age ranging from 18 to 29 years (mean age: 22·33±2·114 years), participated in this study. Reliability was assessed by Cronbach's alpha coefficient and the coefficient of correlation was used to assess correlation between items and test-retest reliability. The construct validity was tested by factorial analysis. Convergent construct validity was tested by comparison of PIDAQ scores with the aesthetic component of the index of orthodontic treatment needs (IOTN-AC) and perception of occlusion scale (POS), respectively. Discriminant construct validity was assessed by differences in score for those who demand treatment and those who did not. The response rate was 100%. One hundred and twenty-three individuals had a demand for orthodontic treatment. The Nepali PIDAQ had excellent reliability with Cronbach's alpha of 0·945, corrected item correlation between 0·525 and 0·790 and overall test-retest reliability of 0·978. The construct validity was good with formation of a new sub-domain 'Dental self-consciousness'. The scale had good correlation with IOTN-AC and POS fulfilling convergent construct validity. The discriminant construct validity was proved by significant differences in scores for subjects with demand and without demand for treatment. To conclude, Nepali version of PIDAQ has good psychometric properties and can be used effectively in this population group for further research.
R package to estimate intracluster correlation coefficient with confidence interval for binary data.

PubMed

Chakraborty, Hrishikesh; Hossain, Akhtar

2018-03-01

The Intracluster Correlation Coefficient (ICC) is a major parameter of interest in cluster randomized trials that measures the degree to which responses within the same cluster are correlated. There are several types of ICC estimators and its confidence intervals (CI) suggested in the literature for binary data. Studies have compared relative weaknesses and advantages of ICC estimators as well as its CI for binary data and suggested situations where one is advantageous in practical research. The commonly used statistical computing systems currently facilitate estimation of only a very few variants of ICC and its CI. To address the limitations of current statistical packages, we developed an R package, ICCbin, to facilitate estimating ICC and its CI for binary responses using different methods. The ICCbin package is designed to provide estimates of ICC in 16 different ways including analysis of variance methods, moments based estimation, direct probabilistic methods, correlation based estimation, and resampling method. CI of ICC is estimated using 5 different methods. It also generates cluster binary data using exchangeable correlation structure. ICCbin package provides two functions for users. The function rcbin() generates cluster binary data and the function iccbin() estimates ICC and it's CI. The users can choose appropriate ICC and its CI estimate from the wide selection of estimates from the outputs. The R package ICCbin presents very flexible and easy to use ways to generate cluster binary data and to estimate ICC and it's CI for binary response using different methods. The package ICCbin is freely available for use with R from the CRAN repository (https://cran.r-project.org/package=ICCbin). We believe that this package can be a very useful tool for researchers to design cluster randomized trials with binary outcome. Copyright © 2017 Elsevier B.V. All rights reserved.
CORRELATION BETWEEN METAL-CERAMIC BOND STRENGTH AND COEFFICIENT OF LINEAR THERMAL EXPANSION DIFFERENCE

PubMed Central

Lopes, Stella Crosara; Pagnano, Valéria Oliveira; Rollo, João Manuel Domingos de Almeida; Leal, Mônica Barbosa; Bezzon, Osvaldo Luiz

2009-01-01

The purpose of this study was to evaluate the metal-ceramic bond strength (MCBS) of 6 metal-ceramic pairs (2 Ni-Cr alloys and 1 Pd-Ag alloy with 2 dental ceramics) and correlate the MCBS values with the differences between the coefficients of linear thermal expansion (CTEs) of the metals and ceramics. Verabond (VB) Ni-Cr-Be alloy, Verabond II (VB2), Ni-Cr alloy, Pors-on 4 (P), Pd-Ag alloy, and IPS (I) and Duceram (D) ceramics were used for the MCBS test and dilatometric test. Forty-eight ceramic rings were built around metallic rods (3.0 mm in diameter and 70.0 mm in length) made from the evaluated alloys. The rods were subsequently embedded in gypsum cast in order to perform a tensile load test, which enabled calculating the CMBS. Five specimens (2.0 mm in diameter and 12.0 mm in length) of each material were made for the dilatometric test. The chromel-alumel thermocouple required for the test was welded into the metal test specimens and inserted into the ceramics. ANOVA and Tukey's test revealed significant differences (p=0.01) for the MCBS test results (MPa), with PI showing higher MCBS (67.72) than the other pairs, which did not present any significant differences. The CTE (10-6 °C-1) differences were: VBI (0.54), VBD (1.33), VB2I (-0.14), VB2D (0.63), PI (1.84) and PD (2.62). Pearson's correlation test (r=0.17) was performed to evaluate of correlation between MCBS and CTE differences. Within the limitations of this study and based on the obtained results, there was no correlation between MCBS and CTE differences for the evaluated metal-ceramic pairs. PMID:19274398
Nuclear Overhauser Enhancement Imaging of Glioblastoma at 7 Tesla: Region Specific Correlation with Apparent Diffusion Coefficient and Histology

PubMed Central

Windschuh, Johannes; Meissner, Jan-Eric; Zaiss, Moritz; Eidel, Oliver; Kickingereder, Philipp; Nowosielski, Martha; Wiestler, Benedikt; Sahm, Felix; Floca, Ralf Omar; Neumann, Jan-Oliver; Wick, Wolfgang; Heiland, Sabine; Bendszus, Martin; Schlemmer, Heinz-Peter; Ladd, Mark Edward; Bachert, Peter; Radbruch, Alexander

2015-01-01

Objective To explore the correlation between Nuclear Overhauser Enhancement (NOE)-mediated signals and tumor cellularity in glioblastoma utilizing the apparent diffusion coefficient (ADC) and cell density from histologic specimens. NOE is one type of chemical exchange saturation transfer (CEST) that originates from mobile macromolecules such as proteins and might be associated with tumor cellularity via altered protein synthesis in proliferating cells. Patients and Methods For 15 patients with newly diagnosed glioblastoma, NOE-mediated CEST-contrast was acquired at 7 Tesla (asymmetric magnetization transfer ratio (MTRasym) at 3.3ppm, B1 = 0.7 μT). Contrast enhanced T1 (CE-T1), T2 and diffusion-weighted MRI (DWI) were acquired at 3 Tesla and coregistered. The T2 edema and the CE-T1 tumor were segmented. ADC and MTRasym values within both regions of interest were correlated voxelwise yielding the correlation coefficient rSpearman (rSp). In three patients who underwent stereotactic biopsy, cell density of 12 specimens per patient was correlated with corresponding MTRasym and ADC values of the biopsy site. Results Eight of 15 patients showed a weak or moderate positive correlation of MTRasym and ADC within the T2 edema (0.16≤rSp≤0.53, p<0.05). Seven correlations were statistically insignificant (p>0.05, n = 4) or yielded rSp≈0 (p<0.05, n = 3). No trend towards a correlation between MTRasym and ADC was found in CE-T1 tumor (-0.310.05, n = 6). The biopsy-analysis within CE-T1 tumor revealed a strong positive correlation between tumor cellularity and MTRasym values in two of the three patients (rSp patient3 = 0.69 and rSp patient15 = 0.87, p<0.05), while the correlation of ADC and cellularity was heterogeneous (rSp patient3 = 0.545 (p = 0.067), rSp patient4 = -0.021 (p = 0.948), rSp patient15 = -0.755 (p = 0.005)). Discussion NOE-imaging is a new contrast promising insight into pathophysiologic processes in glioblastoma regarding cell
A meta-analysis of the validity of FFQ targeted to adolescents.

PubMed

Tabacchi, Garden; Filippi, Anna Rita; Amodio, Emanuele; Jemni, Monèm; Bianco, Antonino; Firenze, Alberto; Mammina, Caterina

2016-05-01

The present work is aimed at meta-analysing validity studies of FFQ for adolescents, to investigate their overall accuracy and variables that can affect it negatively. A meta-analysis of sixteen original articles was performed within the ASSO Project (Adolescents and Surveillance System in the Obesity prevention). The articles assessed the validity of FFQ for adolescents, compared with food records or 24 h recalls, with regard to energy and nutrient intakes. Pearson's or Spearman's correlation coefficients, means/standard deviations, kappa agreement, percentiles and mean differences/limits of agreement (Bland-Altman method) were extracted. Pooled estimates were calculated and heterogeneity tested for correlation coefficients and means/standard deviations. A subgroup analysis assessed variables influencing FFQ accuracy. An overall fair/high correlation between FFQ and reference method was found; a good agreement, measured through the intake mean comparison for all nutrients except sugar, carotene and K, was observed. Kappa values showed fair/moderate agreement; an overall good ability to rank adolescents according to energy and nutrient intakes was evidenced by data of percentiles; absolute validity was not confirmed by mean differences/limits of agreement. Interviewer administration mode, consumption interval of the previous year/6 months and high number of food items are major contributors to heterogeneity and thus can reduce FFQ accuracy. The meta-analysis shows that FFQ are accurate tools for collecting data and could be used for ranking adolescents in terms of energy and nutrient intakes. It suggests how the design and the validation of a new FFQ should be addressed.
The Trojan Lifetime Champions Health Survey: Development, Validity, and Reliability

PubMed Central

Sorenson, Shawn C.; Romano, Russell; Scholefield, Robin M.; Schroeder, E. Todd; Azen, Stanley P.; Salem, George J.

2015-01-01

Context Self-report questionnaires are an important method of evaluating lifespan health, exercise, and health-related quality of life (HRQL) outcomes among elite, competitive athletes. Few instruments, however, have undergone formal characterization of their psychometric properties within this population. Objective To evaluate the validity and reliability of a novel health and exercise questionnaire, the Trojan Lifetime Champions (TLC) Health Survey. Design Descriptive laboratory study. Setting A large National Collegiate Athletic Association Division I university. Patients or Other Participants A total of 63 university alumni (age range, 24 to 84 years), including former varsity collegiate athletes and a control group of nonathletes. Intervention(s) Participants completed the TLC Health Survey twice at a mean interval of 23 days with randomization to the paper or electronic version of the instrument. Main Outcome Measure(s) Content validity, feasibility of administration, test-retest reliability, parallel-form reliability between paper and electronic forms, and estimates of systematic and typical error versus differences of clinical interest were assessed across a broad range of health, exercise, and HRQL measures. Results Correlation coefficients, including intraclass correlation coefficients (ICCs) for continuous variables and κ agreement statistics for ordinal variables, for test-retest reliability averaged 0.86, 0.90, 0.80, and 0.74 for HRQL, lifetime health, recent health, and exercise variables, respectively. Correlation coefficients, again ICCs and κ, for parallel-form reliability (ie, equivalence) between paper and electronic versions averaged 0.90, 0.85, 0.85, and 0.81 for HRQL, lifetime health, recent health, and exercise variables, respectively. Typical measurement error was less than the a priori thresholds of clinical interest, and we found minimal evidence of systematic test-retest error. We found strong evidence of content validity, convergent
Correlation between external and internal respiratory motion: a validation study.

PubMed

Ernst, Floris; Bruder, Ralf; Schlaefer, Alexander; Schweikard, Achim

2012-05-01

In motion-compensated image-guided radiotherapy, accurate tracking of the target region is required. This tracking process includes building a correlation model between external surrogate motion and the motion of the target region. A novel correlation method is presented and compared with the commonly used polynomial model. The CyberKnife system (Accuray, Inc., Sunnyvale/CA) uses a polynomial correlation model to relate externally measured surrogate data (optical fibres on the patient's chest emitting red light) to infrequently acquired internal measurements (X-ray data). A new correlation algorithm based on ɛ -Support Vector Regression (SVR) was developed. Validation and comparison testing were done with human volunteers using live 3D ultrasound and externally measured infrared light-emitting diodes (IR LEDs). Seven data sets (5:03-6:27 min long) were recorded from six volunteers. Polynomial correlation algorithms were compared to the SVR-based algorithm demonstrating an average increase in root mean square (RMS) accuracy of 21.3% (0.4 mm). For three signals, the increase was more than 29% and for one signal as much as 45.6% (corresponding to more than 1.5 mm RMS). Further analysis showed the improvement to be statistically significant. The new SVR-based correlation method outperforms traditional polynomial correlation methods for motion tracking. This method is suitable for clinical implementation and may improve the overall accuracy of targeted radiotherapy.

Cross-cultural Adaptation and Validation of the Medication Regimen Complexity Index Adapted to Spanish.

PubMed

Saez de la Fuente, Javier; Such Diaz, Ana; Cañamares-Orbis, Irene; Ramila, Estela; Izquierdo-Garcia, Elsa; Esteban, Concepcion; Escobar-Rodríguez, Ismael

2016-11-01

The most widely used validated instrument to assess the complexity of medication regimens is the Medication Regimen Complexity Index (MRCI). This study aimed to translate, adapt, and validate a reliable version of the MRCI adapted to Spanish (MRCI-E). The cross-cultural adaptation process consisted of an independent translation by 3 clinical pharmacists and a backtranslation by 2 native English speakers. A reliability analysis was conducted on 20 elderly randomly selected patients. Two clinical pharmacists calculated the MRCI-E from discharge treatments and 2 months later. For the validity analysis, the sample was augmented to 60 patients. Convergent validity was assessed by analyzing the correlation between the number of medications; discriminant validity was stratified by gender; and predictive validity was determined by analyzing the ability to predict readmission and mortality at 3 and 6 months. The MRCI-E retained the original structure of 3 sections. The reliability analysis demonstrated an excellent internal consistency (Cronbach's α=0.83), and the intraclass correlation coefficient exceeded 0.9 in all cases. The correlation coefficient with the number of medications was 0.883 ( P<0.001). No significant differences were found when stratified by gender (3.6; 95%CI=-2.9 to 10.2; P=0.27). Patients who were readmitted at 3 months had a higher MRCI-E score (10.7; 95%CI=4.4 to 17.2; P=0.001). The differences remained significant in patients readmitted at 6 months, but differences in mortality were not detected. The MRCI-E retains the reliability and validity of the original index and provides a suitable tool to assess the complexity of medication regimens in Spanish.
Translation, validity, and reliability of a persian version of the iowa tinnitus handicap questionnaire.

PubMed

Arian Nahad, Homa; Rouzbahani, Masomeh; Jarollahi, Farnoush; Jalaie, Shohreh; Pourbakht, Akram; Mokrian, Helnaz; Mahdi, Parvane; Amali, Amin; Nodin Zadeh, Abdolmajid

2014-04-01

Tinnitus is a common otologic symptom that can seriously affect a patient's quality of life. The purpose of the present study was to translate and validate the Iowa Tinnitus Handicap Questionnaire (THQ) into the Persian language, and to make it applicable as a tool for determining the effects of tinnitus on a patient's life. The main version of the THQ was translated into the Persian language. The agreed Persian version was administered to 150 tinnitus patients. The validity of the Persian THQ was evaluated and internal reliability was confirmed using Cronbach's α-coefficient. Finally, the effect of independent variables such as age, mean patient threshold, gender, and duration of tinnitus were considered in order to determine the psychometric properties of tinnitus. After an exact translation process, the Persian THQ was found to exhibit face validity. In terms of content validity, content validity index in total questionnaire was 0.93. Further, in structural validity measurements, intermediate correlation with annoyance from tinnitus (r=0.49), low correlation with duration of tinnitus (r=0.34) and high correlation with the Tinnitus Handicap Inventory (THI) questionnaire (r=0.84) were demonstrated. Additionally, a negligible effect of gender and age was noted on degree of tinnitus handicap (P= 0.754, P= 0.573, respectively). In the internal reliability assessment for Factors 1, 2, 3, and the whole questionnaire, Cronbach`s α-coefficient was 0.95, 0.92, 0.25 and 0.88, respectively. The Persian version of the Iowa THQ demonstrates high validity and reliability and can be used for the determination of tinnitus handicap and for following-up in the intervention process in Persian tinnitus patients.
Measurement of fatigue: Comparison of the reliability and validity of single-item and short measures to a comprehensive measure.

PubMed

Kim, Hee-Ju; Abraham, Ivo

2017-01-01

Evidence is needed on the clinicometric properties of single-item or short measures as alternatives to comprehensive measures. We examined whether two single-item fatigue measures (i.e., Likert scale, numeric rating scale) or a short fatigue measure were comparable to a comprehensive measure in reliability (i.e., internal consistency and test-retest reliability) and validity (i.e., convergent, concurrent, and predictive validity) in Korean young adults. For this quantitative study, we selected the Functional Assessment of Chronic Illness Therapy-Fatigue for the comprehensive measure and the Profile of Mood States-Brief, Fatigue subscale for the short measure; and constructed two single-item measures. A total of 368 students from four nursing colleges in South Korea participated. We used Cronbach's alpha and item-total correlation for internal consistency reliability and intraclass correlation coefficient for test-retest reliability. We assessed Pearson's correlation with a comprehensive measure for convergent validity, with perceived stress level and sleep quality for concurrent validity and the receiver operating characteristic curve for predictive validity. The short measure was comparable to the comprehensive measure in internal consistency reliability (Cronbach's alpha=0.81 vs. 0.88); test-retest reliability (intraclass correlation coefficient=0.66 vs. 0.61); convergent validity (r with comprehensive measure=0.79); concurrent validity (r with perceived stress=0.55, r with sleep quality=0.39) and predictive validity (area under curve=0.88). Single-item measures were not comparable to the comprehensive measure. A short fatigue measure exhibited similar levels of reliability and validity to the comprehensive measure in Korean young adults. Copyright Â© 2016 Elsevier Ltd. All rights reserved.
Translation, Cross-Cultural Adaptation, and Validation of the Activity Rating Scale for Disorders of the Knee.

PubMed

Flosadottir, Vala; Roos, Ewa M; Ageberg, Eva

2017-09-01

The Activity Rating Scale (ARS) for disorders of the knee evaluates the level of activity by the frequency of participation in 4 separate activities with high demands on knee function, with a score ranging from 0 (none) to 16 (pivoting activities 4 times/wk). To translate and cross-culturally adapt the ARS into Swedish and to assess measurement properties of the Swedish version of the ARS. Cohort study (diagnosis); Level of evidence, 2. The COSMIN guidelines were followed. Participants (N = 100 [55 women]; mean age, 27 years) who were undergoing rehabilitation for a knee injury completed the ARS twice for test-retest reliability. The Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale (TAS), and modernized Saltin-Grimby Physical Activity Level Scale (SGPALS) were administered at baseline to validate the ARS. Construct validity and responsiveness of the ARS were evaluated by testing predefined hypotheses regarding correlations between the ARS, KOOS, TAS, and SGPALS. The Cronbach alpha, intraclass correlation coefficients, absolute reliability, standard error of measurement, smallest detectable change, and Spearman rank-order correlation coefficients were calculated. The ARS showed good internal consistency (α ≈ 0.96), good test-retest reliability (intraclass correlation coefficient >0.9), and no systematic bias between measurements. The standard error of measurement was less than 2 points, and the smallest detectable change was less than 1 point at the group level and less than 5 points at the individual level. More than 75% of the hypotheses were confirmed, indicating good construct validity and good responsiveness of the ARS. The Swedish version of the ARS is valid, reliable, and responsive for evaluating the level of activity based on the frequency of participation in high-demand knee sports activities in young adults with a knee injury.
Translation, Cross-Cultural Adaptation, and Validation of the Activity Rating Scale for Disorders of the Knee

PubMed Central

Flosadottir, Vala; Roos, Ewa M.; Ageberg, Eva

2017-01-01

Background: The Activity Rating Scale (ARS) for disorders of the knee evaluates the level of activity by the frequency of participation in 4 separate activities with high demands on knee function, with a score ranging from 0 (none) to 16 (pivoting activities 4 times/wk). Purpose: To translate and cross-culturally adapt the ARS into Swedish and to assess measurement properties of the Swedish version of the ARS. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The COSMIN guidelines were followed. Participants (N = 100 [55 women]; mean age, 27 years) who were undergoing rehabilitation for a knee injury completed the ARS twice for test-retest reliability. The Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale (TAS), and modernized Saltin-Grimby Physical Activity Level Scale (SGPALS) were administered at baseline to validate the ARS. Construct validity and responsiveness of the ARS were evaluated by testing predefined hypotheses regarding correlations between the ARS, KOOS, TAS, and SGPALS. The Cronbach alpha, intraclass correlation coefficients, absolute reliability, standard error of measurement, smallest detectable change, and Spearman rank-order correlation coefficients were calculated. Results: The ARS showed good internal consistency (α ≈ 0.96), good test-retest reliability (intraclass correlation coefficient >0.9), and no systematic bias between measurements. The standard error of measurement was less than 2 points, and the smallest detectable change was less than 1 point at the group level and less than 5 points at the individual level. More than 75% of the hypotheses were confirmed, indicating good construct validity and good responsiveness of the ARS. Conclusion: The Swedish version of the ARS is valid, reliable, and responsive for evaluating the level of activity based on the frequency of participation in high-demand knee sports activities in young adults with a knee injury. PMID:28979920
Eustachian Tube Mucosal Inflammation Scale Validation Based on Digital Video Images.

PubMed

Kivekäs, Ilkka; Pöyhönen, Leena; Aarnisalo, Antti; Rautiainen, Markus; Poe, Dennis

2015-12-01

The most common cause for Eustachian tube dilatory dysfunction is mucosal inflammation. The aim of this study was to validate a scale for Eustachian tube mucosal inflammation, based on digital video clips obtained during diagnostic rigid endoscopy. A previously described four-step scale for grading the degree of inflammation of the mucosa of the Eustachian tube lumen was used for this validation study. A tutorial for use of the scale, including static images and 10 second video clips, was presented to 26 clinicians with various levels of experience. Each clinician then reviewed 35 short digital video samples of Eustachian tubes from patients and rated the degree of inflammation. A subset of the clinicians performed a second rating of the same video clips at a subsequent time. Statistical analysis of the ratings provided inter- and intrarater reliability scores. Twenty-six clinicians with various levels of experience rated a total of 35 videos. Thirteen clinicians rated the videos twice. The overall correlation coefficient for the rating of inflammation severity was relatively good (0.74, 95% confidence interval, 0.72-0.76). The intralevel correlation coefficient for intrarater reliability was high (0.86). For those who rated videos twice, the intralevel correlation coefficient improved after the first rating (0.73, to 0.76), but improvement was not statistically significant. The inflammation scale used for Eustachian tube mucosal inflammation is reliable and this scale can be used with a high level of consistency by clinicians with various levels of experience.
The Persian Version of the "Life Satisfaction Scale": Construct Validity and Test-Re-Test Reliability among Iranian Older Adults.

PubMed

Moghadam, Manije; Salavati, Mahyar; Sahaf, Robab; Rassouli, Maryam; Moghadam, Mojgan; Kamrani, Ahmad Ali Akbari

2018-03-01

After forward-backward translation, the LSS was administered to 334 Persian speaking, cognitively healthy elderly aged 60 years and over recruited through convenience sampling. To analyze the validity of the model's constructs and the relationships between the constructs, a confirmatory factor analysis followed by PLS analysis was performed. The Construct validity was further investigated by calculating the correlations between the LSS and the "Short Form Health Survey" (SF-36) subscales measuring similar and dissimilar constructs. The LSS was re-administered to 50 participants a month later to assess the reliability. For the eight-factor model of the life satisfaction construct, adequate goodness of fit between the hypothesized model and the model derived from the sample data was attained (positive and statistically significant beta coefficients, good R-squares and acceptable GoF). Construct validity was supported by convergent and discriminant validity, and correlations between the LSS and SF-36 subscales. Minimum Intraclass Correlation Coefficient level of 0.60 was exceeded by all subscales. Minimum level of reliability indices (Cronbach's α, composite reliability and indicator reliability) was exceeded by all subscales. The Persian-version of the Life Satisfaction Scale is a reliable and valid instrument, with psychometric properties which are consistent with the original version.
Reproducibility and validity of a semi-quantitative FFQ for trace elements.

PubMed

Lee, Yujin; Park, Kyong

2016-09-01

The aim of this study was to test the reproducibility and validity of a self-administered FFQ for the Trace Element Study of Korean Adults in the Yeungnam area (SELEN). Study subjects were recruited from the SELEN cohort selected from rural and urban areas in Yeungnam, Korea. A semi-quantitative FFQ with 146 items was developed considering the dietary characteristics of cohorts in the study area. In a validation study, seventeen men and forty-eight women aged 38-62 years completed 3-d dietary records (DR) and two FFQ over a 3-month period. The validity was examined with the FFQ and DR, and the reproducibility was estimated using partial correlation coefficients, the Bland-Altman method and cross-classification. There were no significant differences between the mean intakes of selected nutrients as estimated from FFQ1, FFQ2 and DR. The median correlation coefficients for all nutrients were 0·47 and 0·56 in the reproducibility and validity tests, respectively. Bland-Altman's index and cross-classification showed acceptable agreement between FFQ1 and FFQ2 and between FFQ2 and DR. Ultimately, 78 % of the subjects were classified into the same and adjacent quartiles for most nutrients. In addition, the weighted κ value indicated that the two methods agreed fairly. In conclusion, this newly developed FFQ was a suitable dietary assessment method for the SELEN cohort study.
Development and validation of two equations based on anthropometry, estimating body fat for the Greek adult population.

PubMed

Kanellakis, Spyridon; Skoufas, Efstathios; Khudokonenko, Vladlena; Apostolidou, Eftychia; Gerakiti, Loukia; Andrioti, Maria-Chrysi; Bountouvi, Evangelia; Manios, Yannis

2017-02-01

To validate anthropometric equations in the current literature predicting body fat percentage (%BF) in the Greek population, to develop and validate two anthropometric equations estimating %BF, and to compare them with the retrieved equations. Anthropometric data from 642 Greek adults were incorporated. Dual-energy X-ray absorptiometry was used as reference method. The comparison with other equations was made using Bland-Altman analysis, intraclass correlation coefficient, and Lin's concordance correlation coefficient. Nine of the thirty-one retrieved equations had no statistically significant bias. However, all of them had wide limits of agreement (±8.3 to ±16%BF). The equations accrued were: BF% = -0.615-10.948 × sex + 0.321 × waist circumference + 0.502 × hips circumference-0.39 × forearm circumference - 19.768 × height (m) and BF% = -27.787-5.515 × sex-8.419 × height + 0.145 × waist circumference + 0.270 × hips circumference + 7.509 × log of thigh skinfold + 20.090 × log of sum of skinfolds (bicep + tricep + suprailiac + subscapular)-0.445 × forearm circumference. Bland-Altman's reliability analysis showed no significant bias of -0.058 and -0.148%BF and limits of agreement ±8.100 and ±6.056%BF; the intraclass correlation coefficient was 0.955 and 0.976; and Lin's concordance correlation coefficient was 0.914 and 0.951, respectively. Literature equations performed moderately on this study's population. Therefore, two equations were designed and validated. The first one was simple and easily applicable, with measures obtained from a measuring tape, and the second one more complicated yet more accurate and reliable. Both were found to be reliable for the assessment of body composition in the Greek population. © 2017 The Obesity Society.
The Swedish validation of Edinburgh Postnatal Depression Scale (EPDS) during pregnancy.

PubMed

Rubertsson, Christine; Börjesson, Karin; Berglund, Anna; Josefsson, Ann; Sydsjö, Gunilla

2011-12-01

Around 10-15% of women suffer from depressive illness during pregnancy or the first year postpartum. Depression during pregnancy constitutes a risk for prenatal stress and preterm birth. No validated screening instrument for detecting depression during pregnancy was available in Swedish. We aimed to validate the Edinburgh Postnatal Depression Scale (EPDS) against DSM-IV criteria for depression during pregnancy, establish a reliable cut-off and estimate the correlation between the EPDS and HAD-S (Hospital Anxiety and Depression Scale). In a population-based community sample of 1175 pregnant women, 918 women (78%) answered questionnaires with the EPDS and HAD-S. In all, 121 were interviewed using the PRIME-MD (Primary Care Evaluation of Mental disorders) for diagnosing depression. Women were interviewed in mean gestational week 13 (range 8-21). For the EPDS, a receiver operating characteristic (ROC) curve was calculated for prediction of depression. Pearson's correlation coefficient was used to investigate the association between EPDS and HAD-S scores. The optimal cut-off score on the EPDS scale for detecting depression was ≥13 (standard error coefficient of 1.09 and c-statistics of 0.84) giving a sensitivity of 77% and specificity of 94%. The EPDS scores correlated strongly with the HAD-S, Pearson's correlation was 0.83 (P < 0.0001). This study confirms that the EPDS is a valid screening instrument for detection of depressive symptoms during pregnancy. The EPDS shows persuasive measuring outcomes with an optimal cut-off at ≥13. Healthcare for pregnant women should consider screening procedures and follow-up routines for depressive symptoms.
Validity and reliability of the Self-Reported Physical Fitness (SRFit) survey.

PubMed

Keith, NiCole R; Clark, Daniel O; Stump, Timothy E; Miller, Douglas K; Callahan, Christopher M

2014-05-01

An accurate physical fitness survey could be useful in research and clinical care. To estimate the validity and reliability of a Self-Reported Fitness (SRFit) survey; an instrument that estimates muscular fitness, flexibility, cardiovascular endurance, BMI, and body composition (BC) in adults ≥ 40 years of age. 201 participants completed the SF-36 Physical Function Subscale, International Physical Activity Questionnaire (IPAQ), Older Adults' Desire for Physical Competence Scale (Rejeski), the SRFit survey, and the Rikli and Jones Senior Fitness Test. BC, height and weight were measured. SRFit survey items described BC, BMI, and Senior Fitness Test movements. Correlations between the Senior Fitness Test and the SRFit survey assessed concurrent validity. Cronbach's Alpha measured internal consistency within each SRFit domain. SRFit domain scores were compared with SF-36, IPAQ, and Rejeski survey scores to assess construct validity. Intraclass correlations evaluated test-retest reliability. Correlations between SRFit and the Senior Fitness Test domains ranged from 0.35 to 0.79. Cronbach's Alpha scores were .75 to .85. Correlations between SRFit and other survey scores were -0.23 to 0.72 and in the expected direction. Intraclass correlation coefficients were 0.79 to 0.93. All P-values were 0.001. Initial evaluation supports the SRFit survey's validity and reliability.
Designing a valid and reliable Likert attitude scale on the generation of electricity from nuclear power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calhoun, L.D.

A 15-step flowchart model was applied to the construction of a 20-item long form and a 6-item short form of the scale. Both scales were field-tested on 829 respondents representing a diverse range of subjects: high school juniors and seniors, nuclear engineering students, pre-service teachers, and members of a citizens action group. Both scales are available for immediate use. The 20-item scale appears to be reliable, content valid, and construct valid. Content validity was examined through factor analysis and the use of two separate juries of nuclear experts. Construct validity was examined by application of the known-groups approach. Scale reliabilitymore » and homogeneity were evidenced by a 0.93 coefficient alpha, a range of positive interim correlations of 0.15 to 0.73, and a range of adjusted item-total correlations of 0.46 to 0.80. The 20-item scale also has evaluative quality; means ranged from 2.80 to 3.70. Content validity for the 6-item scale was examined by a jury of nuclear experts. An obtained coefficient alpha of 0.82, a range of interim correlations of 0.51 to 0.72 suggest the scale is reliable and homogeneous. The 6-item short form also appears to have evaluative quality; means ranged from 2.37 to 3.18.« less
Correlation of standardized uptake value and apparent diffusion coefficient in integrated whole-body PET/MRI of primary and recurrent cervical cancer.

PubMed

Grueneisen, Johannes; Beiderwellen, Karsten; Heusch, Philipp; Buderath, Paul; Aktas, Bahriye; Gratz, Marcel; Forsting, Michael; Lauenstein, Thomas; Ruhlmann, Verena; Umutlu, Lale

2014-01-01

To evaluate a potential correlation of the maximum standard uptake value (SUVmax) and the minimum apparent diffusion coefficient (ADCmin) in primary and recurrent cervical cancer based on integrated PET/MRI examinations. 19 consecutive patients (mean age 51.6 years; range 30-72 years) with histopathologically confirmed primary cervical cancer (n = 9) or suspected tumor recurrence (n = 10) were prospectively enrolled for an integrated PET/MRI examination. Two radiologists performed a consensus reading in random order, using a dedicated post-processing software. Polygonal regions of interest (ROI) covering the entire tumor lesions were drawn into PET/MR images to assess SUVmax and into ADC parameter maps to determine ADCmin values. Pearson's correlation coefficients were calculated to assess a potential correlation between the mean values of ADCmin and SUVmax. In 15 out of 19 patients cervical cancer lesions (n = 12) or lymph node metastases (n = 42) were detected. Mean SUVmax (12.5 ± 6.5) and ADCmin (644.5 ± 179.7 × 10(-5) mm2/s) values for all assessed tumor lesions showed a significant but weak inverse correlation (R = -0.342, p < 0.05). When subdivided in primary and recurrent tumors, primary tumors and associated primary lymph node metastases revealed a significant and strong inverse correlation between SUVmax and ADCmin (R = -0.692, p < 0.001), whereas recurrent cancer lesions did not show a significant correlation. These initial results of this emerging hybrid imaging technique demonstrate the high diagnostic potential of simultaneous PET/MR imaging for the assessment of functional biomarkers, revealing a significant and strong correlation of tumor metabolism and higher cellularity in cervical cancer lesions.
Validity and reliability of the Turkish version of the DSM-5 Dissociative Symptoms Severity Scale-Child Form.

PubMed

Yalın Sapmaz, Şermin; Ergin, Dilek; Şen Celasin, Nesrin; Özek Erkuran, Handan; Karaarslan, Duygu; Öztekin, Siğnem; Uzel Tanrıverdi, Bengisu; Köroğlu, Ertuğrul; Aydemir, Ömer

2017-01-01

The goal of this study was to assess the validity and reliability of the Turkish version of the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) Dissociative Symptoms Severity Scale-Child Form. The scale was prepared by translating and then back-translating the DSM-5 Dissociative Symptoms Severity Scale. The study groups included one group of 30 patients diagnosed with posttraumatic stress disorder who were treated in a child and adolescent psychiatry unit and another group of 83 healthy volunteers from middle and high schools in the community. For assessment, the Adolescent Dissociative Experiences Scale (ADES) was used in addition to the DSM-5 Dissociative Symptoms Severity Scale. Regarding the reliability of the DSM-5 Dissociative Symptoms Severity Scale, Cronbach's alpha was .824 and item-total score correlation coefficients were between .464 and .648. The test-retest correlation coefficient was calculated to be r = .784. In terms of construct validity, one factor accounted for 45.2% of the variance. Furthermore, in terms of concurrent validity, the scale showed a high correlation with the ADES. In conclusion, the Turkish version of the DSM-5 Dissociative Symptoms Severity Scale-Child Form is a valid and reliable tool for both clinical practice and research.
Short version of the Depression Anxiety Stress Scale-21: is it valid for Brazilian adolescents?

PubMed Central

da Silva, Hítalo Andrade; dos Passos, Muana Hiandra Pereira; de Oliveira, Valéria Mayaly Alves; Palmeira, Aline Cabral; Pitangui, Ana Carolina Rodarti; de Araújo, Rodrigo Cappato

2016-01-01

ABSTRACT Objective To evaluate the interday reproducibility, agreement and validity of the construct of short version of the Depression Anxiety Stress Scale-21 applied to adolescents. Methods The sample consisted of adolescents of both sexes, aged between 10 and 19 years, who were recruited from schools and sports centers. The validity of the construct was performed by exploratory factor analysis, and reliability was calculated for each construct using the intraclass correlation coefficient, standard error of measurement and the minimum detectable change. Results The factor analysis combining the items corresponding to anxiety and stress in a single factor, and depression in a second factor, showed a better match of all 21 items, with higher factor loadings in their respective constructs. The reproducibility values for depression were intraclass correlation coefficient with 0.86, standard error of measurement with 0.80, and minimum detectable change with 2.22; and, for anxiety/stress: intraclass correlation coefficient with 0.82, standard error of measurement with 1.80, and minimum detectable change with 4.99. Conclusion The short version of the Depression Anxiety Stress Scale-21 showed excellent values of reliability, and strong internal consistency. The two-factor model with condensation of the constructs anxiety and stress in a single factor was the most acceptable for the adolescent population. PMID:28076595
A Bayesian estimate of the concordance correlation coefficient with skewed data.

PubMed

Feng, Dai; Baumgartner, Richard; Svetnik, Vladimir

2015-01-01

Concordance correlation coefficient (CCC) is one of the most popular scaled indices used to evaluate agreement. Most commonly, it is used under the assumption that data is normally distributed. This assumption, however, does not apply to skewed data sets. While methods for the estimation of the CCC of skewed data sets have been introduced and studied, the Bayesian approach and its comparison with the previous methods has been lacking. In this study, we propose a Bayesian method for the estimation of the CCC of skewed data sets and compare it with the best method previously investigated. The proposed method has certain advantages. It tends to outperform the best method studied before when the variation of the data is mainly from the random subject effect instead of error. Furthermore, it allows for greater flexibility in application by enabling incorporation of missing data, confounding covariates, and replications, which was not considered previously. The superiority of this new approach is demonstrated using simulation as well as real-life biomarker data sets used in an electroencephalography clinical study. The implementation of the Bayesian method is accessible through the Comprehensive R Archive Network. Copyright © 2015 John Wiley & Sons, Ltd.
Turkish Version of Kolcaba's Immobilization Comfort Questionnaire: A Validity and Reliability Study.

PubMed

Tosun, Betül; Aslan, Özlem; Tunay, Servet; Akyüz, Aygül; Özkan, Hüseyin; Bek, Doğan; Açıksöz, Semra

2015-12-01

The purpose of this study was to determine the validity and reliability of the Turkish version of the Immobilization Comfort Questionnaire (ICQ). The sample used in this methodological study consisted of 121 patients undergoing lower extremity arthroscopy in a training and research hospital. The validity study of the questionnaire assessed language validity, structural validity and criterion validity. Structural validity was evaluated via exploratory factor analysis. Criterion validity was evaluated by assessing the correlation between the visual analog scale (VAS) scores (i.e., the comfort and pain VAS scores) and the ICQ scores using Spearman's correlation test. The Kaiser-Meyer-Olkin coefficient and Bartlett's test of sphericity were used to determine the suitability of the data for factor analysis. Internal consistency was evaluated to determine reliability. The data were analyzed with SPSS version 15.00 for Windows. Descriptive statistics were presented as frequencies, percentages, means and standard deviations. A p value ≤ .05 was considered statistically significant. A moderate positive correlation was found between the ICQ scores and the VAS comfort scores; a moderate negative correlation was found between the ICQ and the VAS pain measures in the criterion validity analysis. Cronbach α values of .75 and .82 were found for the first and second measurements, respectively. The findings of this study reveal that the ICQ is a valid and reliable tool for assessing the comfort of patients in Turkey who are immobilized because of lower extremity orthopedic problems. Copyright © 2015. Published by Elsevier B.V.
[Estimators of internal consistency in health research: the use of the alpha coefficient].

PubMed

da Silva, Franciele Cascaes; Gonçalves, Elizandra; Arancibia, Beatriz Angélica Valdivia; Bento, Gisele Graziele; Castro, Thiago Luis da Silva; Hernandez, Salma Stephany Soleman; da Silva, Rudney

2015-01-01

Academic production has increased in the area of health, increasingly demanding high quality in publications of great impact. One of the ways to consider quality is through methods that increase the consistency of data analysis, such as reliability which, depending on the type of data, can be evaluated by different coefficients, especially the alpha coefficient. Based on this, the present review systematically gathers scientific articles produced in the last five years, which in a methodological manner gave the α coefficient psychometric use as an estimator of internal consistency and reliability in the processes of construction, adaptation and validation of instruments. The identification of the studies was conducted systematically in the databases BioMed Central Journals, Web of Science, Wiley Online Library, Medline, SciELO, Scopus, Journals@Ovid, BMJ and Springer, using inclusion and exclusion criteria. Data analyses were performed by means of triangulation, content analysis and descriptive analysis. It was found that most studies were conducted in Iran (f=3), Spain (f=2) and Brazil (f=2). These studies aimed to test the psychometric properties of instruments, with eight studies using the α coefficient to assess reliability and nine for assessing internal consistency. All studies were classified as methodological research when their objectives were analyzed. In addition, four studies were also classified as correlational and one as descriptive-correlational. It can be concluded that though the α coefficient is widely used as one of the main parameters for assessing internal consistency of questionnaires in health sciences, its use as an estimator of trust of the methodology used and internal consistency has some critiques that should be considered.
Validation of the Mini-TQ in a Dutch-speaking population: a rapid assessment for tinnitus-related distress.

PubMed

Vanneste, S; Plazier, M; van der Loo, E; Ost, J; Meeus, O; Van de Heyning, P; De Ridder, D

2011-01-01

Up to 30% of the adult population experiences tinnitus at some point in life. The aim of the present study was to validate the Mini-Tinnitus Questionnaire (TQ) in a Dutch-speaking population for measuring tinnitus-related distress and compare it with the extended version normally used in clinical practice and research. We assessed 181 patients at the Tinnitus Research Initiative clinic of Antwerp University Hospital. Twelve items from the TQ chosen by Hiller and Goebel based on the optimal combination of high item correlation, reliability, and sensitivity were selected and correlated to the different subscale and global scores of the TQ. Internal consistency was evaluated using Cronbach's alpha coefficient, and the Guttman split-half coefficient was used to confirm reliability. Correlation to the global TQ score was .93, internal consistency was .87, and reliability was .89. This study further revealed that the Mini-TQ correlates better with the different subscales of the TQ in the Dutch-speaking population. The convergence validity was confirmed, ensuring that this new instrument measures distress. In addition, the norms suggested by Hiller and Goebel were verified and established. Based on these results, the Mini-TQ is recommended as a valid instrument for evaluating tinnitus-related distress in Dutch-speaking populations for a compact, quick, and economical assessment.
Validation of the French version of the Child Post-Traumatic Stress Reaction Index: psychometric properties in French speaking school-aged children.

PubMed

Olliac, Bertrand; Birmes, Philippe; Bui, Eric; Allenou, Charlotte; Brunet, Alain; Claudet, Isabelle; Sales de Gauzy, Jérôme; Grandjean, Hélène; Raynaud, Jean-Philippe

2014-01-01

Although the reliable and valid Child Post-Traumatic Stress Reaction Index (CPTS-RI) is a widely used measure of posttraumatic stress disorder (PTSD) symptoms in children, it has not been validated in French-speaking populations. The present study aims to assess the psychometric properties of the CPTS-RI in three samples of French-speaking school-children. Data was obtained from three samples. Sample 1 was composed of 106 children (mean (SD) age = 11.7(0.7), 50% females) victims of an industrial disaster. Sample 2 was composed of 50 children (mean (SD) age = 10.8(2.6), 44% females) who had received an orthopaedic surgical procedure after an accident. Sample 3 was composed of 106 children (mean (SD) age = 11.7(2.2), 44% females) admitted to an emergency department after a road traffic accident. We tested internal consistency using Cronbach's alpha. We examined test-retest reliability using intraclass correlation coefficient. In order to assess the convergent validity of the French version of the CPTS-RI and the Clinician Administered PTS Scale-Child and Adolescent (CAPS-CA), spearman-correlation coefficient was computed. To verify the validity of the cut-off scores, a ROC curve was constructed which evaluated the sensitivity and specificity of each score compared to the diagnosis with the CAPS-CA. We also used principal components analysis with varimax rotation to study the structure of the French version of the CPTS-RI. Cronbach's alpha coefficient was 0.87 for the French version of the CPTS-RI. Two-week test-retest intraclass correlation coefficient (n = 30) was 0.67. The French version of the CPTS-RI was well correlated with the CAPS-CA (r = 0.76, p < 0.001). Taking the CAPS-CA as the diagnostic reference, with a diagnostic cut-off of >24 for the CPTS-RI, the sensitivity and specificities were 100% and 62.6%, respectively. The French version of the CPTS-RI demonstrated a three-factor structure. The CPTS-RI is reliable and valid in French-speaking children.

Identifying dyspepsia in the Greek population: translation and validation of a questionnaire

PubMed Central

Anastasiou, Foteini; Antonakis, Nikos; Chaireti, Georgia; Theodorakis, Pavlos N; Lionis, Christos

2006-01-01

Background Studies on clinical issues, including diagnostic strategies, are considered to be the core content of general practice research. The use of standardised instruments is regarded as an important component for the development of Primary Health Care research capacity. Demand for epidemiological cross-cultural comparisons in the international setting and the use of common instruments and definitions valid to each culture is bigger than ever. Dyspepsia is a common complaint in primary practice but little is known with respect to its incidence in Greece. There are some references about the Helicobacter Pylori infection in patients with functional dyspepsia or gastric ulcer in Greece but there is no specific instrument for the identification of dyspepsia. This paper reports on the validation and translation into Greek, of an English questionnaire for the identification of dyspepsia in the general population and discusses several possibilities of its use in the Greek primary care. Methods The selected English postal questionnaire for the identification of people with dyspepsia in the general population consists of 30 items and was developed in 1995. The translation and cultural adaptation of the questionnaire has been performed according to international standards. For the validation of the instrument the internal consistency of the items was established using the alpha coefficient of Chronbach, the reproducibility (test – retest reliability) was measured by kappa correlation coefficient and the criterion validity was calculated against the diagnosis of the patients' records using also kappa correlation coefficient. Results The final Greek version of the postal questionnaire for the identification of dyspepsia in the general population was reliably translated. The internal consistency of the questionnaire was good, Chronbach's alpha was found to be 0.88 (95% CI: 0.81–0.93), suggesting that all items were appropriate to measure. Kappa coefficient for
Identifying dyspepsia in the Greek population: translation and validation of a questionnaire.

PubMed

Anastasiou, Foteini; Antonakis, Nikos; Chaireti, Georgia; Theodorakis, Pavlos N; Lionis, Christos

2006-03-04

Studies on clinical issues, including diagnostic strategies, are considered to be the core content of general practice research. The use of standardised instruments is regarded as an important component for the development of Primary Health Care research capacity. Demand for epidemiological cross-cultural comparisons in the international setting and the use of common instruments and definitions valid to each culture is bigger than ever. Dyspepsia is a common complaint in primary practice but little is known with respect to its incidence in Greece. There are some references about the Helicobacter Pylori infection in patients with functional dyspepsia or gastric ulcer in Greece but there is no specific instrument for the identification of dyspepsia. This paper reports on the validation and translation into Greek, of an English questionnaire for the identification of dyspepsia in the general population and discusses several possibilities of its use in the Greek primary care. The selected English postal questionnaire for the identification of people with dyspepsia in the general population consists of 30 items and was developed in 1995. The translation and cultural adaptation of the questionnaire has been performed according to international standards. For the validation of the instrument the internal consistency of the items was established using the alpha coefficient of Chronbach, the reproducibility (test - retest reliability) was measured by kappa correlation coefficient and the criterion validity was calculated against the diagnosis of the patients' records using also kappa correlation coefficient. The final Greek version of the postal questionnaire for the identification of dyspepsia in the general population was reliably translated. The internal consistency of the questionnaire was good, Chronbach's alpha was found to be 0.88 (95% CI: 0.81-0.93), suggesting that all items were appropriate to measure. Kappa coefficient for reproducibility (test - retest
The Malay Version of the Perceived Stress Scale (PSS)-10 is a Reliable and Valid Measure for Stress among Nurses in Malaysia.

PubMed

Sandhu, Sukhvinder Singh; Ismail, Noor Hassim; Rampal, Krishna Gopal

2015-11-01

The Perceived Stress Scale-10 (PSS-10) is widely used to assess stress perception. The aim of this study was to translate the original PSS-10 into Malay and assess the reliability and validity of the Malay version among nurses. The Malay version of the PSS-10 was distributed among 229 nurses from four government hospitals in Selangor State. Test-retest reliability and concurrent validity was conducted with 25 nurses with the Malay version of the Depression Anxiety Stress Scales (DASS) 21. Cronbach's alpha, confirmatory factor analysis (CFA), intraclass correlation coefficient and Pearson's r correlation coefficient were used to determine the psychometric properties of the Malay PSS-10. Two factor components were yielded through exploratory factor analysis with eigenvalues of 3.37 and 2.10, respectively. Both of the factors accounted for 54.6% of the variance. CFA yielded a two-factor structure with satisfactory goodness-of-fit indices [x 2 /df = 2.43; comparative fit index (CFI) = 0.92, goodness-of-fit Index (GFI) = 0.94; standardised root mean square residual (SRMR) = 0.07 and root mean square error of approximation (RMSEA) = 0.08 (90% CI = 0.07-0.09)]. The Cronbach's alpha coefficient for the total items was 0.63 (0.82 for factor 1 and 0.72 for factor 2). The intraclass correlation coefficient (ICC) was 0.81 (95% CI: 0.62-0.91) for test-retest reliability testing after seven days. The total score and the negative component of the PSS-10 correlated significantly with the stress component of the DASS-21: (r = 0.61, P < 0.001) and (r = 0.56, P < 0.004), respectively. The Malay version of the PSS-10 demonstrated a satisfactory level of validity and reliability to assess stress perception. Therefore, this questionnaire is valid in assessing stress perception among nurses in Malaysia.
Measuring limitations in activities of daily living: a population-based validation of a short questionnaire.

PubMed

Elfering, Achim; Cronenberg, Sonja; Grebner, Simone; Tamcan, Oezguer; Müller, Urs

2017-12-01

A newly developed questionnaire assessing limitations in activity of daily living (LADL-Q) that should improve assessment of LADL is tested in a large population-based validation study. This survey was paper-based. Overall, 16,634 individuals who were representative of the working population in the German-speaking part of Switzerland participated in the study. Item analysis was used the final version of the LADL-Q to four items per subscale that correspond to potential problems in three body regions (back and neck, upper extremities, lower extremities). Analysis included tests for reliability, internal consistency, dimensionality and convergent validity. Test-retest reliability coefficients after 2 weeks ranged from 0.82 to 0.99 (Mdn = 0.87), with no item having a coefficient below 0.60. The median item-total coefficients ranged between moderate and good. Correlation coefficients between LADL-Q subscales and three validated clinical instruments (Western Ontario and McMaster Universities osteoarthritis index, shoulder pain disability index, Oswestry) ranged from 0.63 to 0.81. In structural equation modeling the three subscales were significantly related with two important outcomes in occupational rehabilitation: self-reported general health and daily task performance. The new LADL-Q is a brief, reliable and valid tool for assessment of LADL in studies on musculoskeletal health.
Validity of the Brazilian version of the Godin-Shephard Leisure-Time Physical Activity Questionnaire.

PubMed

João, Thaís Moreira São; Rodrigues, Roberta Cunha Matheus; Gallani, Maria Cecília Bueno Jayme; Miura, Cinthya Tamie Passos; Domingues, Gabriela de Barros Leite; Amireault, Steve; Godin, Gaston

2015-09-01

This study provides evidence of construct validity for the Brazilian version of the Godin-Shephard Leisure-Time Physical Activity Questionnaire (GSLTPAQ), a 1-item instrument used among 236 participants referred for cardiopulmonary exercise testing. The Baecke Habitual Physical Activity Questionnaire (Baecke-HPA) was used to evaluate convergent and divergent validity. The self-reported measure of walking (QCAF) evaluated the convergent validity. Cardiorespiratory fitness assessed convergent validity by the Veterans Specific Activity Questionnaire (VSAQ), peak measured (VO2peak) and maximum predicted (VO2pred) oxygen uptake. Partial adjusted correlation coefficients between the GSLTPAQ, Baecke-HPA, QCAF, VO2pred and VSAQ provided evidence for convergent validity; while divergent validity was supported by the absence of correlations between the GSLTPAQ and the Occupational Physical Activity domain (Baecke-HPA). The GSLTPAQ presents level 3 of evidence of construct validity and may be useful to assess leisure-time physical activity among patients with cardiovascular disease and healthy individuals.
Quality of life in head and neck cancer patients after surgical resection: translation into Cantonese and validation of the EORTC QLQ-H&N35.

PubMed

Bower, W F; Vlantis, A C; Chung, T M L; Cheung, S K C; Bjordal, K; van Hasselt, C A

2009-07-01

High convergent and discriminant validity between subscales was achieved after the translation of EORTC QLQ-H&N35 into Cantonese. Most subscales were assessing distinct components of quality of life (QoL). The study aimed to translate the EORTC QLQ-H&N35 cancer module into Cantonese and to confirm validity and reliability for use in a Hong Kong head and neck (H&N) cancer population. An ethnocentric forward-backward translation of EORTC QLQ-H&N35 was conducted by bilingual head and neck health professionals. Discrepancies were identified and problematic wording and concepts revised. Further review preceded pilot testing in 119 postoperative H&N cancer patients. Internal consistency within each subscale, convergent and discriminant validity to check the item relevance and item representativeness within and between subscales were examined. Mean and standard deviations of each subscale and single item and Cronbach's alpha coefficients for subscales were calculated. Six of seven subscales achieved standard reliability (Cronbach's alpha coefficient >0.7). Correlation coefficients between an item and its own subscale were significantly higher than the coefficients with other subscales. Scaling success was found in all subscales. Pearson's correlation coefficient between subscales was <0.70, except between the subscales swallowing and trouble with social eating (r = 0.795), and speech problems and social contact (r = 0.754).
Modeling Group Differences in OLS and Orthogonal Regression: Implications for Differential Validity Studies

ERIC Educational Resources Information Center

Kane, Michael T.; Mroch, Andrew A.

2010-01-01

In evaluating the relationship between two measures across different groups (i.e., in evaluating "differential validity") it is necessary to examine differences in correlation coefficients and in regression lines. Ordinary least squares (OLS) regression is the standard method for fitting lines to data, but its criterion for optimal fit…
The validity and reliability of tinnitus handicap inventory Thai version.

PubMed

Limviriyakul, Siriporn; Supavanich, Walop

2012-11-01

Demonstrate the reliability and validity of the Tinnitus Handicap Inventory Thai Version (THI-T), a self-report measure of tinnitus. A cross-sectional psychometric validation study was used to determine internal consistency reliability and validity of the Tinnitus Handicap Inventory Thai Version at the Otoneurology clinic at Tertiary care center The cross-cultural adaptation of the Tinnitus Handicapped Inventory English version (Newman et al, 1996) was translated into Thai version following the steps indicated by Guillemin et al. The reliability was constructed by using Cronbach's coefficient alpha. The validity was analyzed by the correlation between Tinnitus Handicap Inventory Thai version and the 36-items short form health survey and visual analog scale using Spearman and Pearson test. The result showed good internal consistency reliabilities of total, functional, emotional, and catastrophic scale (a = 0.902, 0.804, 0.831 and 0.661, respectively) of Tinnitus Handicap Inventory Thai Version. Spearman correlation showed the significant correlation of Tinnitus Handicap Inventory to 36-items short form health survey and visual analog scale. Tinnitus Handicap Inventory Thai Version will be a vigorous tool in evaluating tinnitus patients as well as monitoring the progress of their symptoms.
Second-degree Stokes coefficients from multi-satellite SLR

NASA Astrophysics Data System (ADS)

Bloßfeld, Mathis; Müller, Horst; Gerstl, Michael; Štefka, Vojtěch; Bouman, Johannes; Göttl, Franziska; Horwath, Martin

2015-09-01

The long wavelength part of the Earth's gravity field can be determined, with varying accuracy, from satellite laser ranging (SLR). In this study, we investigate the combination of up to ten geodetic SLR satellites using iterative variance component estimation. SLR observations to different satellites are combined in order to identify the impact of each satellite on the estimated Stokes coefficients. The combination of satellite-specific weekly or monthly arcs allows to reduce parameter correlations of the single-satellite solutions and leads to alternative estimates of the second-degree Stokes coefficients. This alternative time series might be helpful for assessing the uncertainty in the impact of the low-degree Stokes coefficients on geophysical investigations. In order to validate the obtained time series of second-degree Stokes coefficients, a comparison with the SLR RL05 time series of the Center of Space Research (CSR) is done. This investigation shows that all time series are comparable to the CSR time series. The precision of the weekly/monthly and coefficients is analyzed by comparing mass-related equatorial excitation functions with geophysical model results and reduced geodetic excitation functions. In case of , the annual amplitude and phase of the DGFI solution agrees better with three of four geophysical model combinations than other time series. In case of , all time series agree very well to each other. The impact of on the ice mass trend estimates for Antarctica are compared based on CSR GRACE RL05 solutions, in which different monthly time series are used for replacing. We found differences in the long-term Antarctic ice loss of Gt/year between the GRACE solutions induced by the different SLR time series of CSR and DGFI, which is about 13 % of the total ice loss of Antarctica. This result shows that Antarctic ice mass loss quantifications must be carefully interpreted.
Design data for radars based on 13.9 GHz Skylab scattering coefficient measurements

NASA Technical Reports Server (NTRS)

Moore, R. K. (Principal Investigator)

1974-01-01

The author has identified the following significant results. Measurements made at 13.9 GHz with the radar scatterometer on Skylab have been combined to produce median curves of the variation of scattering coefficient with angle of incidence out to 45 deg. Because of the large number of observations, and the large area averaged for each measured data point, these curves may be used as a new design base for radars. A reasonably good fit at larger angles is obtained using the theoretical expression based on an exponential height correlation function and also using Lambert's law. For angles under 10 deg, a different fit based on the exponential correlation function, and a fit based on geometric optics expressions are both reasonably valid.
Reliability and Validity of Quantifying Absolute Muscle Hardness Using Ultrasound Elastography

PubMed Central

Chino, Kentaro; Akagi, Ryota; Dohi, Michiko; Fukashiro, Senshi; Takahashi, Hideyuki

2012-01-01

Muscle hardness is a mechanical property that represents transverse muscle stiffness. A quantitative method that uses ultrasound elastography for quantifying absolute human muscle hardness has been previously devised; however, its reliability and validity have not been completely verified. This study aimed to verify the reliability and validity of this quantitative method. The Young’s moduli of seven tissue-mimicking materials (in vitro; Young’s modulus range, 20–80 kPa; increments of 10 kPa) and the human medial gastrocnemius muscle (in vivo) were quantified using ultrasound elastography. On the basis of the strain/Young’s modulus ratio of two reference materials, one hard and one soft (Young’s moduli of 7 and 30 kPa, respectively), the Young’s moduli of the tissue-mimicking materials and medial gastrocnemius muscle were calculated. The intra- and inter-investigator reliability of the method was confirmed on the basis of acceptably low coefficient of variations (≤6.9%) and substantially high intraclass correlation coefficients (≥0.77) obtained from all measurements. The correlation coefficient between the Young’s moduli of the tissue-mimicking materials obtained using a mechanical method and ultrasound elastography was 0.996, which was equivalent to values previously obtained using magnetic resonance elastography. The Young’s moduli of the medial gastrocnemius muscle obtained using ultrasound elastography were within the range of values previously obtained using magnetic resonance elastography. The reliability and validity of the quantitative method for measuring absolute muscle hardness using ultrasound elastography were thus verified. PMID:23029231
Caval Subtraction 2D Phase-Contrast MRI to Measure Total Liver and Hepatic Arterial Blood Flow: Proof-of-Principle, Correlation With Portal Hypertension Severity and Validation in Patients With Chronic Liver Disease.

PubMed

Chouhan, Manil D; Mookerjee, Rajeshwar P; Bainbridge, Alan; Punwani, Shonit; Jones, Helen; Davies, Nathan; Walker-Samuel, Simon; Patch, David; Jalan, Rajiv; Halligan, Steve; Lythgoe, Mark F; Taylor, Stuart A

2017-03-01

Caval subtraction phase-contrast magnetic resonance imaging (PCMRI) noninvasive measurements of total liver blood flow (TLBF) and hepatic arterial (HA) flow have been validated in animal models and translated into normal volunteers, but not patients. This study aims to demonstrate its use in patients with liver cirrhosis, evaluate measurement consistency, correlate measurements with portal hypertension severity, and invasively validate TLBF measurements. Local research ethics committee approval was obtained. Twelve patients (mean, 50.8 ± 3.1 years; 10 men) with histologically confirmed cirrhosis were recruited prospectively, undergoing 2-dimensional PCMRI of the portal vein (PV) and the infrahepatic and suprahepatic inferior vena cava. Total liver blood flow and HA flow were estimated by subtracting infrahepatic from suprahepatic inferior vena cava flow and PV flow from estimated TLBF, respectively. Invasive hepatic venous pressure gradient (HVPG) and indocyanine green (ICG) clearance TLBF were measured within 7 days of PCMRI. Bland-Altman (BA) analysis of agreement, coefficients of variation, and Pearson correlation coefficients were calculated for comparisons with direct inflow PCMRI, HVPG, and ICG clearance. The mean difference between caval subtraction TLBF and direct inflow PCMRI was 6.3 ± 4.2 mL/min/100 g (BA 95% limits of agreement, ±28.7 mL/min/100 g). Significant positive correlations were observed between HVPG and caval subtraction HA fraction (r = 0.780, P = 0.014), but not for HA flow (r = 0.625, P = 0.053), PV flow (r = 0.244, P = 0.469), or caval subtraction TLBF (r = 0.473, P = 0.141). Caval subtraction and ICG TLBF agreement was modest (mean difference, -32.6 ± 16.6 mL/min/100 g; BA 95% limits of agreement, ±79.7 mL/min/100 g), but coefficients of variation were not different (65.7% vs 48.1%, P = 0.28). In this proof-of-principle study, caval subtraction PCMRI measurements are consistent with direct inflow PCMRI, correlate with portal
Evaluation of random errors in Williams’ series coefficients obtained with digital image correlation

NASA Astrophysics Data System (ADS)

Lychak, Oleh V.; Holyns'kiy, Ivan S.

2016-03-01

The use of the Williams’ series parameters for fracture analysis requires valid information about their error values. The aim of this investigation is the development of the method for estimation of the standard deviation of random errors of the Williams’ series parameters, obtained from the measured components of the stress field. Also, the criteria for choosing the optimal number of terms in the truncated Williams’ series for derivation of their parameters with minimal errors is proposed. The method was used for the evaluation of the Williams’ parameters, obtained from the data, and measured by the digital image correlation technique for testing a three-point bending specimen.
Channel correlation and BER performance analysis of coherent optical communication systems with receive diversity over moderate-to-strong non-Kolmogorov turbulence.

PubMed

Fu, Yulong; Ma, Jing; Tan, Liying; Yu, Siyuan; Lu, Gaoyuan

2018-04-10

In this paper, new expressions of the channel-correlation coefficient and its components (the large- and small-scale channel-correlation coefficients) for a plane wave are derived for a horizontal link in moderate-to-strong non-Kolmogorov turbulence using a generalized effective atmospheric spectrum which includes finite-turbulence inner and outer scales and high-wave-number "bump". The closed-form expression of the average bit error rate (BER) of the coherent free-space optical communication system is derived using the derived channel-correlation coefficients and an α-μ distribution to approximate the sum of the square root of arbitrarily correlated Gamma-Gamma random variables. Analytical results are provided to investigate the channel correlation and evaluate the average BER performance. The validity of the proposed approximation is illustrated by Monte Carlo simulations. This work will help with further investigation of the fading correlation in spatial diversity systems.
Improvement of geomagnetic core field modeling with a priori information about Gauss coefficient correlations

NASA Astrophysics Data System (ADS)

Schachtschneider, R.; Rother, M.; Lesur, V.

2013-12-01

We introduce a method that enables us to account for existing correlations between Gauss coefficients in core field modelling. The information about the correlations are obtained from a highly accurate field model based on CHAMP data, e.g. the GRIMM-3 model. We compute the covariance matrices of the geomagnetic field, the secular variation, and acceleration up to degree 18 and use these in the regularization scheme of the core field inversion. For testing our method we followed two different approaches by applying it to two different synthetic satellite data sets. The first is a short data set with a time span of only three months. Here we test how the information about correlations help to obtain an accurate model when only very little information are available. The second data set is a large one covering several years. In this case, besides reducing the residuals in general, we focus on the improvement of the model near the boundaries of the data set where the accerelation is generally more difficult to handle. In both cases the obtained covariance matrices are included in the damping scheme of the regularization. That way information from scales that could otherwise not be resolved by the data can be extracted. We show that by using this technique we are able to improve the models of the field and the secular variation for both, the short and the long term data set, compared to approaches using more conventional regularization techniques.
Ecology of Floristic Quality Assessment: testing for correlations between coefficients of conservatism, species traits and mycorrhizal responsiveness.

PubMed

Bauer, Jonathan T; Koziol, Liz; Bever, James D

2018-02-01

Many plant species are limited to habitats relatively unaffected by anthropogenic disturbance, so protecting these undisturbed habitats is essential for plant conservation. Coefficients of conservatism (C values) were developed as indicators of a species' sensitivity to anthropogenic disturbance, and these values are used in Floristic Quality Assessment as a means of assessing natural areas and ecological restoration. However, assigning of these values is subjective and improved quantitative validation of C values is needed. We tested whether there are consistent differences in life histories between species with high and low C values. To do this, we grew 54 species of tallgrass prairie plants in a greenhouse and measured traits that are associated with trade-offs on the fast-slow continuum of life-history strategies. We also grew plants with and without mycorrhizal fungi as a test of these species' reliance on this mutualism. We compared these traits and mycorrhizal responsiveness to C values. We found that six of the nine traits we measured were correlated with C values, and together, traits predicted up to 50 % of the variation in C values. Traits including fast growth rates and greater investment in reproduction were associated with lower C values, and slow growth rates, long-lived leaves and high root:shoot ratios were associated with higher C values. Additionally, plants with high C values and a slow life history were more responsive to mutualisms with mycorrhizal fungi. Overall, our results connect C values with life-history trade-offs, indicating that high C value species tend to share a suite of traits associated with a slow life history.
The Crucial Role of Error Correlation for Uncertainty Modeling of CFD-Based Aerodynamics Increments

NASA Technical Reports Server (NTRS)

Hemsch, Michael J.; Walker, Eric L.

2011-01-01

The Ares I ascent aerodynamics database for Design Cycle 3 (DAC-3) was built from wind-tunnel test results and CFD solutions. The wind tunnel results were used to build the baseline response surfaces for wind-tunnel Reynolds numbers at power-off conditions. The CFD solutions were used to build increments to account for Reynolds number effects. We calculate the validation errors for the primary CFD code results at wind tunnel Reynolds number power-off conditions and would like to be able to use those errors to predict the validation errors for the CFD increments. However, the validation errors are large compared to the increments. We suggest a way forward that is consistent with common practice in wind tunnel testing which is to assume that systematic errors in the measurement process and/or the environment will subtract out when increments are calculated, thus making increments more reliable with smaller uncertainty than absolute values of the aerodynamic coefficients. A similar practice has arisen for the use of CFD to generate aerodynamic database increments. The basis of this practice is the assumption of strong correlation of the systematic errors inherent in each of the results used to generate an increment. The assumption of strong correlation is the inferential link between the observed validation uncertainties at wind-tunnel Reynolds numbers and the uncertainties to be predicted for flight. In this paper, we suggest a way to estimate the correlation coefficient and demonstrate the approach using code-to-code differences that were obtained for quality control purposes during the Ares I CFD campaign. Finally, since we can expect the increments to be relatively small compared to the baseline response surface and to be typically of the order of the baseline uncertainty, we find that it is necessary to be able to show that the correlation coefficients are close to unity to avoid overinflating the overall database uncertainty with the addition of the increments.
A new scale for the assessment of performance and capacity of hand function in children with hemiplegic cerebral palsy: reliability and validity studies.

PubMed

Rosa-Rizzotto, M; Visonà Dalla Pozza, L; Corlatti, A; Luparia, A; Marchi, A; Molteni, F; Facchin, P; Pagliano, E; Fedrizzi, E

2014-10-01

In hemiplegic children, the recognition of the activity limitation pattern and the possibility of grading its severity are relevant for clinicians while planning interventions, monitoring results, predicting outcomes. Aim of the study is to examine the reliability and validity of Besta Scale, an instrument used to measure in hemiplegic children from 18 months to 12 years of age both grasp on request (capacity) and spontaneous use of upper limb (performance) in bimanual play activities and in ADL. Psychometric analysis of reliability and of validity of the Besta scale was performed. Outpatient study sample Reliability study: A sample of 39 patients was enrolled. The administration of Besta scale was video-recorded in a standardized manner. All videos were scored by 20 independent raters on subsequent viewing. 3 raters randomly selected from the 20-raters group rescored the same video two years later for intra-rater reliability. Intra and inter-rater reliability were calculated using Intraclass Correlation Coefficient (ICC) and Kendall's coefficient (K), respectively. Internal consistency reliability was assessed using Alpha's Chronbach coefficient. Validity study: a sample of 105 children was assessed 5 times (at t0 and 2, 3, 6 and 12 months later) by 20 independent raters. Each patient underwent at the same time to QUEST and Besta scale administration and assessment. Criterion validity was calculated using rho-Pearson coefficient. Reliability study: The inter-rater reliability calculated with Kendall's coefficient resulted moderate K=0.47. The intra-rater (or test-retest) reliability for 3 raters was excellent (ICC=0.927). The Cronbach's alpha for internal consistency was 0.972. Validity study: Besta scale showed a good criterion validity compared to QUEST increasing by age and severity of impairment. Rho Pearson's correlation coefficient r was 0.81 (P<0.0001). Limitations. Besta scales in infants finds hard to distinguish between mild to moderately impaired hand
Boredom proneness--the development and correlates of a new scale.

PubMed

Farmer, R; Sundberg, N D

1986-01-01

This article reports the development, validation, and correlates of a self-report measure of boredom proneness. The 28-item Boredom Proneness (BP) Scale demonstrates satisfactory levels of internal consistency (coefficient alpha = .79) and test-retest reliability (r = .83) over a 1-week interval. Evidence of validity for the BP is supported by correlations with other boredom measures and from a set of studies evaluating interest and attention in the classroom. Other hypothesized relationships with boredom were tested, with significant positive associations found with depression, hopelessness, perceived effort, loneliness, and amotivational orientation. Additional findings indicate boredom proneness to be negatively related to life satisfaction and autonomy orientation. The relationship of boredom to other affective states is discussed, and directions for future research are outlined.
Reliability and validity of simplified Chinese version of Swiss Spinal Stenosis Questionnaire for patients with degenerative lumbar spinal stenosis.

PubMed

Yi, Honglei; Wei, Xianzhao; Zhang, Wei; Chen, Ziqiang; Wang, Xinhui; Ji, Xinran; Zhu, Xiaodong; Wang, Fei; Xu, Ximing; Li, Zhikun; Fan, Jianping; Wang, Chuanfeng; Chen, Kai; Zhang, Guoyou; Zhao, Yinchuan; Li, Ming

2014-05-01

This was a prospective clinical validation study. To evaluate the reliability and validity of the adapted simplified Chinese version of Swiss Spinal Stenosis (SC-SSS) Questionnaire. The SSS Questionnaire is a reliable and valid instrument to assess the perception of function and pain for patients with degenerative lumbar spinal stenosis. However, there is no culturally adapted SSS Questionnaire for use in mainland China. This was a prospective clinical validation study. The adaption was conducted according to International Quality of Life Assessment Project guidelines. To examine the psychometric properties of the adapted SC-SSS Questionnaire, a sample of 105 patients with lumbar spinal stenosis were included. Thirty-two patients were randomly selected to evaluate the test-retest reliability. Reliability assessment of the SC-SSS Questionnaire was determined by calculating Cronbach α and intraclass coefficient values. Concurrent validity was assessed by correlating SC-SSS Questionnaire scores with relevant domains of the 36-Item Short Form Health Survey. Cronbach α of the symptom severity scale, physical function scale, patients, and satisfaction scale of SC-SSS Questionnaire are 0.89, 0.86, 0.91, respectively, which revealed very good internal consistency. The test-retest reproducibility was found to be excellent with the intraclass correlation coefficient of 0.93, 0.91, and 0.95. In terms of concurrent validity, SC-SSS Questionnaire had good correlation with physical functioning and bodily pain of 36-Item Short Form Health Survey (r = 0.663, 0.653) and low correlation with mental health (r = 0.289). The physical function scale had good correlation with physical functioning of 36-Item Short Form Health Survey (r = 0.637), whereas the rest had moderate correlation. The satisfaction scale score was highly correlated with the change in the symptom severity (r = 0.71) and physical function (r = 0.68) scale score. The SC-SSS Questionnaire showed satisfactory

Validity and Reliability of the Turkish Chronic Pain Acceptance Questionnaire

PubMed Central

Akmaz, Hazel Ekin; Uyar, Meltem; Kuzeyli Yıldırım, Yasemin; Akın Korhan, Esra

2018-01-01

Background: Pain acceptance is the process of giving up the struggle with pain and learning to live a worthwhile life despite it. In assessing patients with chronic pain in Turkey, making a diagnosis and tracking the effectiveness of treatment is done with scales that have been translated into Turkish. However, there is as yet no valid and reliable scale in Turkish to assess the acceptance of pain. Aims: To validate a Turkish version of the Chronic Pain Acceptance Questionnaire developed by McCracken and colleagues. Study Design: Methodological and cross sectional study. Methods: A simple randomized sampling method was used in selecting the study sample. The sample was composed of 201 patients, more than 10 times the number of items examined for validity and reliability in the study, which totaled 20. A patient identification form, the Chronic Pain Acceptance Questionnaire, and the Brief Pain Inventory were used to collect data. Data were collected by face-to-face interviews. In the validity testing, the content validity index was used to evaluate linguistic equivalence, content validity, construct validity, and expert views. In reliability testing of the scale, Cronbach’s α coefficient was calculated, and item analysis and split-test reliability methods were used. Principal component analysis and varimax rotation were used in factor analysis and to examine factor structure for construct concept validity. Results: The item analysis established that the scale, all items, and item-total correlations were satisfactory. The mean total score of the scale was 21.78. The internal consistency coefficient was 0.94, and the correlation between the two halves of the scale was 0.89. Conclusion: The Chronic Pain Acceptance Questionnaire, which is intended to be used in Turkey upon confirmation of its validity and reliability, is an evaluation instrument with sufficient validity and reliability, and it can be reliably used to examine patients’ acceptance of chronic pain
Concurrent validity and reliability of the Alberta Infant Motor Scale in infants at dual risk for motor delays.

PubMed

Snyder, Patricia; Eason, Jane M; Philibert, Darbi; Ridgway, Andrea; McCaughey, Tiffany

2008-01-01

Concurrent validity of scores for the Alberta Infant Motor Scale (AIMS) and the Peabody Developmental Gross Motor Scale-2 (PDGMS-2) was examined with a sample of 35 infants at dual risk for motor delays or disabilities. Dual risk was defined as low birthweight (correlation coefficients were high (r= .90 to .97), with the highest correlation between PDGMS-2 locomotion subscale and AIMS total score. Correlation coefficients were lower for infants > 9 months of age. Novice examiners' scores on both measures closely approximated those of experienced examiners (ICC range = .98 to .99). The results support concurrent validity of the AIMS and PDGMS-2 for infants at dual risk and have implications for using the AIMS in high-risk follow-up programs, particularly in relation to evaluating functional components of motor performance and ease of administration.
Validity and reliability of a self-report instrument to assess social support and physical environmental correlates of physical activity in adolescents

PubMed Central

2012-01-01

Background The purpose of this study was to examine the internal consistency, test-retest reliability, construct validity and predictive validity of a new German self-report instrument to assess the influence of social support and the physical environment on physical activity in adolescents. Methods Based on theoretical consideration, the short scales on social support and physical environment were developed and cross-validated in two independent study samples of 9 to 17 year-old girls and boys. The longitudinal sample of Study I (n = 196) was recruited from a German comprehensive school, and subjects in this study completed the questionnaire twice with a between-test interval of seven days. Cronbach’s alphas were computed to determine the internal consistency of the factors. Test-retest reliability of the latent factors was assessed using intra-class coefficients. Factorial validity of the scales was assessed using principle components analysis. Construct validity was determined using a cross-validation technique by performing confirmatory factor analysis with the independent nationwide cross-sectional sample of Study II (n = 430). Correlations between factors and three measures of physical activity (objectively measured moderate-to-vigorous physical activity (MVPA), self-reported habitual MVPA and self-reported recent MVPA) were calculated to determine the predictive validity of the instrument. Results Construct validity of the social support scale (two factors: parental support and peer support) and the physical environment scale (four factors: convenience, public recreation facilities, safety and private sport providers) was shown. Both scales had moderate test-retest reliability. The factors of the social support scale also had good internal consistency and predictive validity. Internal consistency and predictive validity of the physical environment scale were low to acceptable. Conclusions The results of this study indicate moderate to good
CROSS-CULTURAL ADAPTATION AND VALIDATION OF THE ITCHING SEVERITY SCALE IN CHILDREN AND ADOLESCENTS WITH ATOPIC DERMATITIS.

PubMed

Bruscky, Dayanne Mota Veloso; Melo, Ana Caroline Cavalcanti Dela Bianca; Sarinho, Emanuel Sávio Cavalcanti

2017-01-01

To translate, adapt and validate the Itch Severity Scale to a Brazilian version (ISS-Ped) in order to measure the severity of pruritus in children and adolescents with atopic dermatitis. This is a methodological study of validation of an instrument following recommended protocols. The translated version was evaluated by a group of experts including one professional with experience in instrument validation, three English teachers, one linguistics teacher and seven allergists. After this, the scale was applied to 42 parents of children aged between 2 and 18 years old with atopic dermatitis, and 42 parents of children without pruritic diseases. Results were evaluated according to the severity of atopic dermatitis and disease control, and they were compared between groups with and without atopic dermatitis. More than 90% of the questions were clear to the parents. The ISS-Ped showed a strong positive correlation with the severity of atopic dermatitis (Pearson: 0.74; p<0.001) and a good correlation with the control of dermatitis (point-biserial correlation coefficient: 0.65; p<0.001). The scale showed excellent internal consistency (Cronbach's α: 0.96) and adequate test and retest agreement (95% confidence interval of intraclass correlation coefficient: 0.89-0.99; p<0.001). The ISS-Ped is a feasible, valid, reliable and satisfactorily equivalent. The translated scale was appropriate to assess the severity of itching in children and adolescents with eczema, allowing comparisons in the clinical practice and in the research setting.
Validity and reliability of Arabic MOS social support survey.

PubMed

Dafaalla, Mohamed; Farah, Abdulraheem; Bashir, Sheima; Khalil, Ammar; Abdulhamid, Rabab; Mokhtar, Mousab; Mahadi, Mohamed; Omer, Zulfa; Suliman, Asgad; Elkhalifa, Mohammed; Abdelgadir, Hanin; Kheir, Abdelmoneim E M; Abdalrahman, Ihab

2016-01-01

We aimed to generate a valid reliable Arabic version of MOS social support survey (MOS-SSS). We did a cross sectional study in medical students of Faculty of Medicine in Khartoum, Sudan. We did a clustered random sampling in 500 students of which 487 were suitable for analysis. We followed the standard translation process for translating the MOS-SSS. We accomplished factor analysis to assess construct validity, and generated item-scales correlations to evaluate the convergent and discriminant validity. We extracted the Cronbach's α and Spearman Brown coefficient of spit half method to determine internal consistency. We measured stability by correlation between the scores of the MOS survey taken at two different occasions with ten days apart in 252 participants. All items correlated highly (0.788 or greater) with their hypothesized scales. All items in subscales correlated higher by two standard errors with their own scale than with any other scale. Principle component analysis with varimax rotation was conducted on the 19 items and examination of scree plot graphically suggested 4 predominant factors that account for 72 % of variance. It showed high loadings, ranging from 0.720 to 0.84 for items of emotional support, 0.699-0.845 for tangible support, 0.518-0.823 for affectionate support, and 0.740-0.816 for positive social interaction. Cronbach's alpha for overall MOS scale and subscales indicated high internal consistency. The test-retest correlation showed weak correlation between the test and retest (ranges from 0.04 to 0.104). The Arabic MOS-SSS had high validity and internal consistency.
Translation, Cross Cultural Adaptation and Validation of the Lee Chronic Graft-versus-Host Disease (GVHD) Symptom Scale in a Brazilian Population

PubMed Central

de Souza, Clarissa Vasconcellos; Vigorito, Afonso Celso; Miranda, Eliana C M; Garcia, Celso; Colturato, Vergílio Antonio Rensi; Mauad, Marcos Augusto; Moreira, Maria Cláudia Rodrigues; da Silva Bouzas, Luis Fernando; Lermontov, Simone; Hamerschlak, Nelson; Rodrigues, Morgani; de Almeida Barros, Jose Carlos; Chiattone, Ricardo; Lee, Stephanie J; Flowers, Mary ED

2017-01-01

The Lee chronic graft-versus-disease (cGVHD) Symptom Scale is a patient-reported instrument developed and validated in English to measure symptoms and functional impact of cGVHD. This tool has not been validated in a Latin America population. The Brazil-Seattle Chronic GVHD Consortium conducted a multicenter study at five Brazilian institutions to validate the Lee cGVHD Symptom Scale in adults with chronic GVHD. Study objectives included the translation and validation of the instrument in Brazilian Portuguese and evaluation of the correlation with other quality of life (QoL) tools (i.e., Medical Outcomes Study Short Form 36 [SF-36] and the Functional Assessment of Chronic Illness Therapy with Bone Marrow Transplant subscale [FACT-BMT]). Translation and validation were according to the American Association of Orthopedic Surgeons Outcome Committee guideline. Spearman’s correlation coefficient was used to measure construct validity. Reliability was assessed using Cronbach’s alpha and intraclass correlation coefficients. Between April 2011 and August 2012, 47 patients with cGVHD by the 2005 NIH criteria were enrolled in this study. Cohort median age was 48 (23–69) years and 29 (62%) were male. Lee cGVHD Symptom Scale reliability was adequate (Cronbach’s alpha 0.62–0.83). The correlations between similar domains of the Lee cGVHD Symptom Scale, SF-36 and FACT-BMT were moderate to high. The Brazilian Portuguese version of the Lee cGVHD Symptom Scale is valid and reliable and can be used in clinical trials of cGVHD in Brazil. PMID:27058616
Cross-cultural adaptation and validation of the Korean version of the Oxford shoulder score.

PubMed

Roh, Young Hak; Noh, Jung Ho; Kim, Woo; Oh, Joo Han; Gong, Hyun Sik; Baek, Goo Hyun

2012-01-01

The Oxford shoulder score (OSS) is being used increasingly and has been adapted cross-culturally in some Western countries. On the other hand, there are few validated translations of the OSS in Asian countries. This study translated and adapted cross-culturally the original OSS to produce a Korean version, and assessed the validity and reliability of the Korean version of the OSS (Korean OSS). One hundred and five patients with shoulder pain caused by degenerative or inflammatory disorders completed the Korean OSS and Korean disability of arm, shoulder and hand (DASH). In addition, the pain score by a visual analog scale (VAS) during activity and at rest, subjective assessment of activities of daily living (ADL), the active range of motion (ROM), and measurements of the abduction strength (strength) were included in the validation process. There were no major linguistic or cultural problems during the forward and backward translations of the MHQ, except for a minor change due to cultural discrepancies in eating such as using a spoon and chopsticks by one dominant hand instead of a knife and fork by two hands. The internal consistency was high (Cronbach's alpha 0.91). The reproducibility test showed no significant difference (Intra-class coefficient 0.95). The construct validity, which was tested by the Pearson correlation coefficient revealed a strong correlation (r > 0.6) between the Korean OSS against subscale of DASH disability/symptom, DASH work and ADL, as well as a moderate correlation (0.3 < r < 0.6) with the DASH sports/music, strength, ROM, pain during activity and pain at rest. The Korean OSS proved to be valid by demonstrating a significant correlation with the patient-based upper extremity questionnaire and clinical assessment. The application and evaluation of the instrument is feasible and understandable among patients in Korea.
Validity of EuroQOL-5D, time trade-off, and standard gamble for age-related macular degeneration in the Singapore population

PubMed Central

Au Eong, K G; Chan, E W; Luo, N; Wong, S H; Tan, N W H; Lim, T H; Wagle, A M

2012-01-01

Background/aims Utility values of age-related macular degeneration (AMD) in Asian patients are unknown. This study aims to assess utility values and construct validity of the EuroQOL-5D (EQ-5D), time trade-off (TTO), and standard gamble (SG) instruments in the Singapore multi-ethnic AMD population. Methods Cross-sectional, two-centre, institution-based study. Visual acuity (VA), clinical AMD severity, and utility scores on the EQ-5D, TTO, and SG were obtained from 338 AMD patients. VA was analysed in terms of the better-seeing eye (BEVA), worse-seeing eye (WEVA), and weighted average of both eyes (WVA). We evaluated SG on the perfect health-death (SG(death)) and binocular perfect vision-binocular blindness (SG(blindness)) scales. Construct validity was determined by testing a priorihypotheses relating the EQ-5D, TTO, and SG utility scores to VA and clinical AMD severity. Results The mean utilities on the EQ-5D, TTO, SG(death), and SG(blindness) were 0.89, 0.81, 0.86, and 0.90, respectively. EQ-5D scores correlated weakly with BEVA, WEVA, and WVA (Pearson's correlation coefficients −0.291, −0.247, and −0.305 respectively, P<0.001 for all). SG(death) and SG(blindness) demonstrated no correlation with BEVA, WEVA, or WVA (Pearson's correlation coefficients, range −0.06 to −0.125). TTO showed weak association only with WEVA and WVA (correlation coefficients −0.237, −0.228, P<0.0001), but not with BEVA (correlation coefficient −0.161). Clinical AMD severity correlated with EQ-5D and SG(death), but not with TTO and SG(blindness) (P=0.004, 0.002, 0.235, and 0.069, respectively). Conclusions AMD has a negative impact on utilities, although utility scores were high compared with Western cohorts. EQ-5D, TTO, and SG showed suboptimal construct validity, suggesting that health status utilities may not be sufficiently robust for cost-utility analyses in this population. PMID:22222257
Test–retest reliability and validity of a web-based food-frequency questionnaire for adolescents aged 13–14 to be used in the Norwegian Mother and Child Cohort Study (MoBa)

PubMed Central

Øverby, Nina Cecilie; Johannesen, Elisabeth; Jensen, Grete; Skjaevesland, Anne-Kirsti; Haugen, Margaretha

2014-01-01

Background The assessment of food intake is challenging and prone to errors; it is therefore important to consider the reliability and validity of the assessment methods. Objective The aim of this study was to analyze the reproducibility and validity of a developed food-frequency questionnaire (FFQ) for use among adolescents. Design In total, 58 students (aged 13–14) from four different schools in the southern part of Norway participated in the reproducibility study of filling out the FFQ 4 weeks apart. In addition, 93 students participated in the relative validity study where the FFQ was compared to 2×24-hour dietary recalls, while 92 students participated in the absolute validity study where the intakes of fatty acids and vitamin D from the FFQ were compared to fatty acids and 25-hydroxy-vitamin D3 in whole blood. Results The median Spearman correlation coefficient for all nutrients in the test–retest reliability study was 0.57. The median Spearman correlation for all nutrients in the relative validity study was 0.26, while the correlations coefficients were low in the absolute validity study with n-3 fatty acid coefficients ranging from 0.05 to 0.25, and absent for vitamin D (r=0.000). Conclusion The test–retest reproducibility was considered good, the relative validity was considered poor to good, and the absolute validity was considered poor. However, the results are comparable to other studies among adolescents. PMID:25371661
Dietary intakes assessed by 24-h recalls in peri-urban African adolescents: validity of energy intake compared with estimated energy expenditure.

PubMed

Rankin, D; Ellis, S M; Macintyre, U E; Hanekom, S M; Wright, H H

2011-08-01

The objective of this study is to determine the relative validity of reported energy intake (EI) derived from multiple 24-h recalls against estimated energy expenditure (EE(est)). Basal metabolic rate (BMR) equations and physical activity factors were incorporated to calculate EE(est). This analysis was nested in the multidisciplinary PhysicaL Activity in the Young study with a prospective study design. Peri-urban black South African adolescents were investigated in a subsample of 131 learners (87 girls and 44 boys) from the parent study sample of 369 (211 girls and 158 boys) who had all measurements taken. Pearson correlation coefficients and Bland-Altman plots were calculated to identify the most accurate published equations to estimate BMR (P<0.05 statistically significant). EE(est) was estimated using BMR equations and estimated physical activity factors derived from Previous Day Physical Activity Recall questionnaires. After calculation of EE(est), the relative validity of reported energy intake (EI(rep)) derived from multiple 24-h recalls was tested for three data subsets using Pearson correlation coefficients. Goldberg's formula identified cut points (CPs) for under and over reporting of EI. Pearson correlation coefficients between calculated BMRs ranged from 0.97 to 0.99. Bland-Altman analyses showed acceptable agreement (two equations for each gender). One equation for each gender was used to calculate EE(est). Pearson correlation coefficients between EI(rep) and EE(est) for three data sets were weak, indicating poor agreement. CPs for physical activity groups showed under reporting in 87% boys and 95% girls. The 24-h recalls measured at five measurements over 2 years offered poor validity between EI(rep) and EE(est).
Development and validation of the Healthy-Unhealthy Music Scale

PubMed Central

Saarikallio, Suvi; Gold, Christian; McFerran, Katrina

2015-01-01

Background Music is an integral part of life in youth, and although it has been acknowledged that musical behavior reflects broader psychosocial aspects of adolescent behavior, no measurement instruments have been specifically designed for assessing musical engagement as an indicator of adolescent wellbeing and/or symptomatology. This study was conducted in order to develop and validate a scale for assessing musical engagement as an indicator of proneness for depression in youth. Method Items were developed based on the literature and a prior grounded theory analysis and three surveys (N = 54, N = 187, N = 211) were conducted to select, refine, test, and validate the items. Scale structure was investigated through interitem correlations, exploratory and confirmatory factor analyses (EFA, CFA), and concurrent validity was tested with correlations to depression and wellbeing. Results The final Healthy-Unhealthy Music Scale (HUMS) consists of 13 items that are divided into Healthy and Unhealthy subscales. Cronbach's alpha coefficients were .78 for Healthy and .83 for Unhealthy. The concurrent validity of the HUMS was confirmed through correlations to wellbeing, happiness and school satisfaction on one hand and depression, rumination, and stress on the other. Conclusions The HUMS is as a promising instrument for screening musical engagement that is indicative of proneness for depression in youth. PMID:26726295
German validation of the Conners Adult ADHD Rating Scales (CAARS) II: reliability, validity, diagnostic sensitivity and specificity.

PubMed

Christiansen, H; Kis, B; Hirsch, O; Matthies, S; Hebebrand, J; Uekermann, J; Abdel-Hamid, M; Kraemer, M; Wiltfang, J; Graf, E; Colla, M; Sobanski, E; Alm, B; Rösler, M; Jacob, C; Jans, T; Huss, M; Schimmelmann, B G; Philipsen, A

2012-07-01

The German version of the Conners Adult ADHD Rating Scales (CAARS) has proven to show very high model fit in confirmative factor analyses with the established factors inattention/memory problems, hyperactivity/restlessness, impulsivity/emotional lability, and problems with self-concept in both large healthy control and ADHD patient samples. This study now presents data on the psychometric properties of the German CAARS-self-report (CAARS-S) and observer-report (CAARS-O) questionnaires. CAARS-S/O and questions on sociodemographic variables were filled out by 466 patients with ADHD, 847 healthy control subjects that already participated in two prior studies, and a total of 896 observer data sets were available. Cronbach's-alpha was calculated to obtain internal reliability coefficients. Pearson correlations were performed to assess test-retest reliability, and concurrent, criterion, and discriminant validity. Receiver Operating Characteristics (ROC-analyses) were used to establish sensitivity and specificity for all subscales. Coefficient alphas ranged from .74 to .95, and test-retest reliability from .85 to .92 for the CAARS-S, and from .65 to .85 for the CAARS-O. All CAARS subscales, except problems with self-concept correlated significantly with the Barrett Impulsiveness Scale (BIS), but not with the Wender Utah Rating Scale (WURS). Criterion validity was established with ADHD subtype and diagnosis based on DSM-IV criteria. Sensitivity and specificity were high for all four subscales. The reported results confirm our previous study and show that the German CAARS-S/O do indeed represent a reliable and cross-culturally valid measure of current ADHD symptoms in adults. Copyright © 2011 Elsevier Masson SAS. All rights reserved.
The development and validation of a questionnaire for rotator cuff disorders: The Functional Shoulder Score

PubMed Central

Ibrahim, Edward F; Petrou, Charalambos; Galanos, Antonis

2015-01-01

Background The purpose of the present study was to validate the Functional Shoulder Score (FSS), a new patient-reported outcome score specifically designed to evaluate patients with rotator cuff disorders. Methods One hundred and nineteen patients were assessed using two shoulder scoring systems [the FSS and the Constant–Murley Score (CMS)] at 3 weeks pre- and 6 months post-arthroscopic rotator cuff surgery. The reliability, validity, responsiveness and interpretability of the FSS were evaluated. Results Reliability analysis (test–retest) showed an intraclass correlation coefficient value of 0.96 [95% confidence interval (CI) = 0.92 to 0.98]. Internal consistency analysis revealed a Cronbach's alpha coefficient of 0.93. The Pearson correlation coefficient FSS-CMS was 0.782 pre-operatively and 0.737 postoperatively (p < 0.0005). There was a statistically significant increase in FSS scores postoperatively, an effect size of 3.06 and standardized response mean of 2.80. The value for minimal detectable change was ±8.38 scale points (based on a 90% CI) and the minimal clinically important difference for improvement was 24.7 ± 5.4 points. Conclusions The FSS is a patient-reported outcome measure that can easily be incorporated into clinical practice, providing a quick, reliable, valid and practical measure for rotator cuff problems. The questionnaire is highly sensitive to clinical change. PMID:27582986
Validity and reliability of the Fels physical activity questionnaire for children.

PubMed

Treuth, Margarita S; Hou, Ningqi; Young, Deborah R; Maynard, L Michele

2005-03-01

The aim was to evaluate the reliability and validity of the Fels physical activity questionnaire (PAQ) for children 7-19 yr of age. A cross-sectional study was conducted among 130 girls and 99 boys in elementary (N=70), middle (N=81), and high (N=78) schools in rural Maryland. Weight and height were measured on the initial school visit. All the children then wore an Actiwatch accelerometer for 6 d. The Fels PAQ for children was given on two separate occasions to evaluate reliability and was compared with accelerometry data to evaluate validity. The reliability of the Fels PAQ for the girls, boys, and the elementary, middle, and high school age groups range was r=0.48-0.76. For the elementary school children, the correlation coefficient examining validity between the Fels PAQ total score and Actiwatch (counts per minute) was 0.34 (P=0.004). The correlation coefficients were lower in middle school (r=0.11, P=0.31) and high school (r=0.21, P=0.006) adolescents. The sport index of the Fels PAQ for children had the highest validity in the high school participants (r=0.34, P=0.002). The Fels PAQ for children is moderately reliable for all age groups of children. Validity of the Fels PAQ for children is acceptable for elementary and high school students when the total activity score or the sport index is used. The sport index was similar to the total score for elementary students but was a better measure of physical activity among high school students.
Patient Assessment of Constipation Quality of Life Questionnaire: Translation, Cultural Adaptation, Reliability, and Validity of the Persian Version.

PubMed

Nikjooy, Afsaneh; Jafari, Hassan; Saba, Maryam A; Ebrahimi, Naghmeh; Mirzaei, Rezvan

2018-05-01

The Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire is the most validated and the most specific tool for measuring the quality of life of patients with constipation. Over 120 million people live in countries whose official language is Persian. There is no reported Persian version of the PAC-QOL questionnaire yet. The aim of this study was to translate and culturally adapt the PAC-QOL questionnaire and to assess its reliability and validity among Persian patients with chronic constipation. Following the translation and cultural adaptation of the PAC-QOL questionnaire to Persian, 100 patients (mean±SD age=40.51±13.67) with constipation were recruited for validity measurement and 20 patients were re-examined for reliability. Content validity was assessed based on the opinions of an expert committee and the floor/ceiling effect. Construct validity was evaluated according to the hypothesis test. The SF-36 questionnaire was used for concurrent criterion validity, intra-class correlation coefficient for reliability, and Cronbach's alpha for internal consistency. The content validity of the PAC-QOL questionnaire was proven, and there was no floor/ceiling effect. Construct validity also was confirmed based on the hypothesis test. The overall Cronbach's alpha of the PAC-QOL questionnaire was 0.92 (range=0.72-0.92), and the overall intra-class correlation coefficient of the questionnaire was 0.88 (range=0.69-0.87). The correlation between the SF-36 and PAC-QOL questionnaires was moderate. The Persian version of the PAC-QOL questionnaire demonstrated good validity and reliability properties in chronic constipation. Accordingly, Persian researchers and clinicians can benefit from this questionnaire in further research and assessment of treatment outcomes.
Development, linguistic and clinimetric validation of the WOMAC VA3.01 Bangla for Bangladesh Index.

PubMed

Rabbani, M G; Haq, S A; Bellamy, N; Islam, M N; Choudhury, M R; Naheed, A; Ahmed, S; Shahin, A

2015-06-01

The aim of this study was to develop and to validate a Bengali version of the Western Ontario and McMaster Osteoarthritis (WOMAC) index in Bangladesh. The WOMAC was translated into the local language of Bangladesh (Bengali) and adapted in the local sociocultural context, following the standard guidelines by Beaton et al. Content validity of the preliminary Bengali version was assessed by using the index of content validity (ICV) and floor and ceiling effects. Patients were assessed at the Department of Rheumatology of Bangabandhu Sheikh Mujib Medical University and were diagnosed to have knee OA by American College of Rheumatology criteria and recruited according to the requirements of the validation study. Convergent and divergent validity were measured by comparing with Health Assessment Questionnaire (HAQ) and the Short Form-36 (SF-36), and internal consistency was assessed using Cronbach's alpha coefficient. The questionnaire was readministered to 40 patients within a week for assessing reliability by using intra-class correlation coefficient (ICC) and Spearman's rank correlation coefficient. In addition, factor analysis of Bengali WOMAC questionnaire was performed to examine the number of factors influencing a common set of items. A Bengali version was developed with changes in three items to suit local practices. The ICV of the content validity was 1 for all items. The Bengali WOMAC had similar construct validity when compared to the HAQ (ρ 0.74, n = 70) and SF-36 bodily pain and physical functioning. It had dissimilar construct validity to SF-36 mental health domain except WOMAC pain. Factor analysis revealed five factors with eigenvalues of more than 1.0. Cronbach's alpha and ICC exceeded 0.7 in all domains. In the test-retest reliability testing, Spearman's ρ for all items exceeded 0.4 (n = 40). This study has demonstrated that the Bengali version of WOMAC is a valid tool for assessing quality of life of patients with knee osteoarthritis in Bangladesh
Cross-Cultural adaption, validity and reliability of a Hindi version of the Corah's Dental Anxiety Scale.

PubMed

Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha

2018-01-01

Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah's Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach's alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach's alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study.
[Testing reliability and validity of reduced substitutes for leadership scales(rd-SLS)].

PubMed

Kim, Jeong-Hee

2005-10-01

This paper was conducted to test the reliability and validity of rd-SLS, developed by Podsakoff, et al. (1993) which measured 'substitutes for leadership'. The subjects were 345 nurses in 5 general hospitals. Cronbach's and the Guttman split-half coefficient were used to test the reliability of rd-SLS. Factor analysis, and the correlations of the rv-SLS and SLS with rd-SLS were used for convergent and discriminant validity. Cronbach's data was 0.76 and the Guttman split-half coefficient was 0.52. Twelve factors evolved by factor analysis, which explained 70.4% of the total variance. This result was similar to previous study results. However, 'Indifference toward organizational rewards'-related items were classified two factors. It was not clear t hat the rd-SLS consisted of 13 concepts(factors). The correlations of the rv-SLS and SLS with the rd-SLS were 0.93 and 0.87 respectively. The rd-SLS showed a moderate degree of validity and reliability. Thus, it is recommended to use the rd-SLS in general nursing organizations for screening for leadership substitutes. In addition, it is necessary to clarify the concept of organizational rewards. In a further study, the factor structure of the rd-SLS may be considered.
Determination of molecular diffusion coefficient in n-alkane binary mixtures: empirical correlations.

PubMed

De Mezquia, D Alonso; Bou-Ali, M Mounir; Larrañaga, M; Madariaga, J A; Santamaría, C

2012-03-08

In this work we have measured the molecular diffusion coefficient of the n-alkane binary series nC(i)-nC(6), nC(i)-nC(10), and nC(i)-nC(12) at 298 K and 1 atm and a mass fraction of 0.5 by using the so-called sliding symmetric tubes technique. The results show that the diffusion coefficient at this concentration is proportional to the inverse viscosity of the mixture. In addition, we have also measured the diffusion coefficient of the systems nC(12)-nC(6), nC(12)-nC(7), and nC(12)-nC(8) as a function of concentration. From the data obtained, it is shown that the diffusion coefficient of the n-alkane binary mixtures at any concentration can be calculated from the molecular weight of the components and the dynamic viscosity of the corresponding mixture at 50% mass fraction.
Evaluation of the reliability and validity for X16 balance testing scale for the elderly.

PubMed

Ju, Jingjuan; Jiang, Yu; Zhou, Peng; Li, Lin; Ye, Xiaolei; Wu, Hongmei; Shen, Bin; Zhang, Jialei; He, Xiaoding; Niu, Chunjin; Xia, Qinghua

2018-05-10

Balance performance is considered as an indicator of functional status in the elderly, a large scale population screening and evaluation in the community context followed by proper interventions would be of great significance at public health level. However, there has been no suitable balance testing scale available for large scale studies in the unique community context of urban China. A balance scale named X16 balance testing scale was developed, which was composed of 3 domains and 16 items. A total of 1985 functionally independent and active community-dwelling elderly adults' balance abilities were tested using the X16 scale. The internal consistency, split-half reliability, content validity, construct validity, discriminant validity of X16 balance testing scale were evaluated. Factor analysis was performed to identify alternative factor structure. The Eigenvalues of factors 1, 2, and 3 were 8.53, 1.79, and 1.21, respectively, and their cumulative contribution to the total variance reached 72.0%. These 3 factors mainly represented domains static balance, postural stability, and dynamic balance. The Cronbach alpha coefficient for the scale was 0.933. The Spearman correlation coefficients between items and its corresponding domains were ranged from 0.538 to 0.964. The correlation coefficients between each item and its corresponding domain were higher than the coefficients between this item and other domains. With the increase of age, the scores of balance performance, domains static balance, postural stability, and dynamic balance in the elderly declined gradually (P < 0.001). With the increase of age, the proportion of the elderly with intact balance performance decreased gradually (P < 0.001). The reliability and validity of the X16 balance testing scale is both adequate and acceptable. Due to its simple and quick use features, it is practical to be used repeatedly and routinely especially in community setting and on large scale screening.

Validity and reliability of the Brazilian version of Yale-Brown obsessive compulsive scale-shopping version (YBOCS-SV).

PubMed

Leite, Priscilla Lourenço; Filomensky, Tatiana Zambrano; Black, Donald W; Silva, Adriana Cardoso

2014-08-01

The Yale-Brown Obsessive Compulsive Scale-Shopping Version (YBOCS-SV) is considered the gold standard in the assessment of shopping severity. It is designed to assess cognitions and behaviors relating to compulsive buying behavior. The present study aims to assess the validity of the Brazilian version of this scale. For the study, composed the sample 610 participants: 588 subjects of a general population and 22 compulsive buyers. Factorial analysis was performed to assess the relations and the correlation between the YBOCS-SV, the Compulsive Buying Scale (CBS), and Richmond Compulsive Buying Scale (RCBS), was assessed using Pearson coefficient, for study of convergent and divergent validity. Cronbach's alpha coefficients were used to assess internal consistency. The results show good to excellent psychometric parameters for the YBOCS-SV in its Brazilian version. With regard to correlations, the YBOCS-SV is inversely and proportionally correlated with CBS and the RCBS, indicating that the YBOCS-SV is an excellent instrument for screening compulsive buying. The YBOCS-SV presented high alpha coefficient of Cronbach's alpha (0.92), demonstrating good reliability. The Brazilian version of the YBOCS-SV is indicated to diagnose compulsive buying disorder, and likely use for the purposes intended in the Brazilian population. Copyright © 2014 Elsevier Inc. All rights reserved.
The Children's Dermatology Life Quality Index (CDLQI): linguistic and cultural validation in Serbian.

PubMed

Janković, Slavenka; Vukićević, Jelica; Djordjević, Sanja; Janković, Janko; Marinković, Jelena; Erić, Miloš

2013-01-01

The Children's Dermatology Life Quality Index (CDLQI) evaluates the impact of skin diseases on the patient's quality of life. The purpose of the study was to translate and to validate the CDLQI into Serbian. The CDLQI was translated into Serbian following international recommendations for translation and cultural adaptation. The validation study was carried out on a large cohort of secondary schoolchildren who self-reported acne. Translating the CDLQI consisted of forward translation, reconciliation, back translation, back-translation review, and cognitive debriefing. The good internal consistency of the scale was demonstrated with a Cronbach alpha coefficient of 0.87. A Spearman correlation coefficient of 0.66 between the CDLQI and the Cardiff Acne Disability Index (CADI) was deemed satisfactory to demonstrate concurrent validity. The translation, cross-cultural adaptation, and psychometric qualities of the CDLQI were satisfactory, enabling its application in clinical practice and future studies.
Reliability and validity of the Japanese version of the Resilience Scale and its short version.

PubMed

Nishi, Daisuke; Uehara, Ritei; Kondo, Maki; Matsuoka, Yutaka

2010-11-17

The clinical relevance of resilience has received considerable attention in recent years. The aim of this study is to demonstrate the reliability and validity of the Japanese version of the Resilience Scale (RS) and short version of the RS (RS-14). The original English version of RS was translated to Japanese and the Japanese version was confirmed by back-translation. Participants were 430 nursing and university psychology students. The RS, Center for Epidemiologic Studies Depression Scale (CES-D), Rosenberg Self-Esteem Scale (RSES), Social Support Questionnaire (SSQ), Perceived Stress Scale (PSS), and Sheehan Disability Scale (SDS) were administered. Internal consistency, convergent validity and factor loadings were assessed at initial assessment. Test-retest reliability was assessed using data collected from 107 students at 3 months after baseline. Mean score on the RS was 111.19. Cronbach's alpha coefficients for the RS and RS-14 were 0.90 and 0.88, respectively. The test-retest correlation coefficients for the RS and RS-14 were 0.83 and 0.84, respectively. Both the RS and RS-14 were negatively correlated with the CES-D and SDS, and positively correlated with the RSES, SSQ and PSS (all p < 0.05), although the correlation between the RS and CES-D was somewhat lower than that in previous studies. Factor analyses indicated a one-factor solution for RS-14, but as for RS, the result was not consistent with previous studies. This study demonstrates that the Japanese version of RS has psychometric properties with high degrees of internal consistency, high test-retest reliability, and relatively low concurrent validity. RS-14 was equivalent to the RS in internal consistency, test-retest reliability, and concurrent validity. Low scores on the RS, a positive correlation between the RS and perceived stress, and a relatively low correlation between the RS and depressive symptoms in this study suggest that validity of the Japanese version of the RS might be relatively low
Pancreatic neuroendocrine tumour: Correlation of apparent diffusion coefficient or WHO classification with recurrence-free survival.

PubMed

Kim, Mimi; Kang, Tae Wook; Kim, Young Kon; Kim, Seong Hyun; Kwon, Wooil; Ha, Sang Yun; Ji, Sang A

2016-03-01

To evaluate the correlation between grade of pancreatic neuroendocrine tumours (pNETs) based on the 2010 World Health Organization (WHO) classification and the apparent diffusion coefficient (ADC), and to assess whether the ADC value and WHO classification can predict recurrence-free survival (RFS) after surgery for pNETs. This retrospective study was approved by the Institutional Review Board. The requirement for informed consent was waived. Between March 2009 and November 2014, forty-nine patients who underwent magnetic resonance (MR) imaging with diffusion-weighted image and subsequent surgery for single pNETs were included. Correlations among qualitative MR imaging findings, quantitative ADC values, and WHO classifications were assessed. An ordered logistic regression test was used to control for tumour size as a confounding factor. The association between ADC value (or WHO classification) and RFS was analysed. All tumors (n=49) were classified as low- (n=29, grade 1), intermediate- (n=17, grade 2), and high-grade (n=3, grade 3), respectively. The mean ADC of pNETs was moderately negatively correlated with WHO classification before and after adjustment for tumour size (ρ=-0.64, p<0.001 and ρ=-0.55, p=0.001 respectively). RFS was significantly associated with WHO classification (p=0.007), but not with the ADC value (p=0.569). The ADC value of pNETs is moderately correlated with WHO tumour grade, regardless of tumour size. However, the WHO tumour classification of pNET may be more suitable for predicting RFS than the ADC value. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Validation of a Survey Questionnaire on Organ Donation: An Arabic World Scenario

PubMed Central

Agarwal, Tulika Mehta; Al-Thani, Hassan; Al Maslamani, Yousuf

2018-01-01

Objective To validate a questionnaire for measuring factors influencing organ donation and transplant. Methods The constructed questionnaire was based on the theory of planned behavior by Ajzen Icek and had 45 questions including general inquiry and demographic information. Four experts on the topic, Arabic culture, and the Arabic and English languages established content validity through review. It was quantified by content validity index (CVI). Construct validity was established by principal component analysis (PCA), whereas internal consistency was checked by Cronbach's Alpha and intraclass correlation coefficient (ICC). Statistical analysis was performed by SPSS 22.0 statistical package. Results Content validity in the form of S-CVI/Average and S-CVI/UA was 0.95 and 0.82, respectively, suggesting adequate relevance content of the questionnaire. Factor analysis indicated that the construct validity for each domain (knowledge, attitudes, beliefs, and intention) was 65%, 71%, 77%, and 70%, respectively. Cronbach's Alpha and ICC coefficients were 0.90, 0.67, 0.75, and 0.74 and 0.82, 0.58, 0.61, and 0.74, respectively, for the domains. Conclusion The questionnaire consists of 39 items on knowledge, attitudes, beliefs, and intention domains which is valid and reliable tool to use for organ donation and transplant survey. PMID:29593894
Precancerous esophageal epithelia are associated with significantly increased scattering coefficients

PubMed Central

Su, Jing-Wei; Lin, Yang-Hsien; Chiang, Chun-Ping; Lee, Jang-Ming; Hsieh, Chao-Mao; Hsieh, Min-Shu; Yang, Pei-Wen; Wang, Chen-Ping; Tseng, Ping-Huei; Lee, Yi-Chia; Sung, Kung-Bin

2015-01-01

The progression of epithelial precancers into cancer is accompanied by changes of tissue and cellular structures in the epithelium. Correlations between the structural changes and scattering coefficients of esophageal epithelia were investigated using quantitative phase images and the scattering-phase theorem. An ex vivo study of 14 patients demonstrated that the average scattering coefficient of precancerous epithelia was 37.8% higher than that of normal epithelia from the same patient. The scattering coefficients were highly correlated with morphological features including the cell density and the nuclear-to-cytoplasmic ratio. A high interpatient variability in scattering coefficients was observed and suggests identifying precancerous lesions based on the relative change in scattering coefficients. PMID:26504630
Synkinesis assessment in facial palsy: validation of the Dutch Synkinesis Assessment Questionnaire.

PubMed

Kleiss, Ingrid J; Beurskens, Carien H G; Stalmeier, Peep F M; Ingels, Koen J A O; Marres, Henri A M

2016-06-01

The objective of this study is to validate an existing health-related quality of life questionnaire for patients with synkinesis in facial palsy for implementation in the Dutch language and culture. The Synkinesis Assessment Questionnaire was translated into the Dutch language using a forward-backward translation method. A pilot test with the translated questionnaire was performed in 10 patients with facial palsy and 10 normal subjects. Finally, cross-cultural adaption was accomplished at our outpatient clinic for facial palsy. Analyses for internal consistency, test-retest reliability, and construct validity were performed. Sixty-six patients completed the Dutch Synkinesis Assessment Questionnaire and the Dutch Facial Disability Index. Cronbach's α, representing internal consistency, was 0.80. Test-retest reliability was 0.53 (Spearman's correlation coefficient, P < 0.01). Correlations with the House-Brackmann score, Sunnybrook score, Facial Disability Index physical function, and social/well-being function were -0.29, 0.20, -0.29, and -0.32, respectively. Correlation with the Sunnybrook synkinesis subscore was 0.50 (Spearman's correlation coefficient). The Dutch Synkinesis Assessment Questionnaire shows good psychometric values and can be implemented in the management of Dutch-speaking patients with facial palsy and synkinesis in the Netherlands. Translation of the instrument into other languages may lead to widespread use, making evaluation, and comparison possible among different providers.
Correlation between electrical conductivity and apparent diffusion coefficient in breast cancer: effect of necrosis on magnetic resonance imaging.

PubMed

Kim, Soo-Yeon; Shin, Jaewook; Kim, Dong-Hyun; Kim, Eun-Kyung; Moon, Hee Jung; Yoon, Jung Hyun; You, Jai Kyung; Kim, Min Jung

2018-03-06

To investigate the correlation between conductivity and ADC in invasive ductal carcinoma according to the presence of necrosis on MRI. Eighty-one women with invasive ductal carcinoma ≥1 cm on T2-weighted fast spin echo sequence of preoperative MRI were included. Phase-based MR electric properties tomography was used to reconstruct conductivity. Mean ADC was measured. Necrosis was defined as an area with very high T2 signal intensity. The relationship between conductivity and ADC was examined using Spearman's correlation coefficient (r). Multiple linear regression analysis was performed to identify factors associated with conductivity or ADC. In the total group, conductivity showed negative correlation with ADC (r = -0.357, p = 0.001). This correlation was maintained in the subgroup without necrosis (n = 53, r = -0.455, p = 0.001), but not in the subgroup with necrosis (n = 28, r = -0.080, p = 0.687). The correlation between the two parameters was different according to necrosis (r = -0.455 vs -0.080, p = 0.047). HER2 enriched subtype was independently associated with conductivity (p = 0.029). Necrosis on MRI was independently associated with ADC (p = 0.027). Conductivity shows negative correlation with ADC that is abolished by the presence of necrosis on MRI. • Electric conductivity showed negative correlation with ADC • However, the correlation was abolished by the presence of necrosis on MRI • HER2-enriched subtype was independently associated with conductivity • Necrosis on MRI was independently associated with ADC.
CROSS-CULTURAL ADAPTATION AND VALIDATION OF THE KOREAN VERSION OF THE CUMBERLAND ANKLE INSTABILITY TOOL.

PubMed

Ko, Jupil; Rosen, Adam B; Brown, Cathleen N

2015-12-01

The Cumberland Ankle Instability Tool (CAIT) is a valid and reliable patient reported outcome used to assess the presence and severity of chronic ankle instability (CAI). The CAIT has been cross-culturally adapted into other languages for use in non-English speaking populations. However, there are no valid questionnaires to assess CAI in individuals who speak Korean. The purpose of this study was to translate, cross-culturally adapt, and validate the CAIT, for use in a Korean-speaking population with CAI. Cross-cultural reliability study. The CAIT was cross-culturally adapted into Korean according to accepted guidelines and renamed the Cumberland Ankle Instability Tool-Korean (CAIT-K). Twenty-three participants (12 males, 11 females) who were bilingual in English and Korean were recruited and completed the original and adapted versions to assess agreement between versions. An additional 168 national level Korean athletes (106 male, 62 females; age = 20.3 ± 1.1 yrs), who participated in ≥ 90 minutes of physical activity per week, completed the final version of the CAIT-K twice within 14 days. Their completed questionnaires were assessed for internal consistency, test-retest reliability, criterion validity, and construct validity. For bilingual participants, intra-class correlation coefficients (ICC2,1) between the CAIT and the CAIT-K for test-retest reliability were 0.95 (SEM=1.83) and 0.96 (SEM=1.50) in right and left limbs, respectively. The Cronbach's alpha coefficients were 0.92 and 0.90 for the CAIT-K in right and left limbs, respectively. For native Korean speakers, the CAIT-K had high internal consistency (Cronbach's α=0.89) and intra-class correlation coefficient (ICC2,1 = 0.94, SEM=1.72), correlation with the physical component score (rho=0.70, p = 0.001) of the Short-Form Health Survey (SF-36), and the Kaiser-Meyer-Olkin score was 0.87. The original CAIT was translated, cross-culturally adapted, and validated from English to Korean
Increased correlation coefficient between the written test score and tutors' performance test scores after training of tutors for assessment of medical students during problem-based learning course in Malaysia.

PubMed

Jaiprakash, Heethal; Min, Aung Ko Ko; Ghosh, Sarmishtha

2016-03-01

This paper is aimed at finding if there was a change of correlation between the written test score and tutors' performance test scores in the assessment of medical students during a problem-based learning (PBL) course in Malaysia. This is a cross-sectional observational study, conducted among 264 medical students in two groups from November 2010 to November 2012. The first group's tutors did not receive tutor training; while the second group's tutors were trained in the PBL process. Each group was divided into high, middle and low achievers based on their end-of-semester exam scores. PBL scores were taken which included written test scores and tutors' performance test scores. Pearson correlation coefficient was calculated between the two kinds of scores in each group. The correlation coefficient between the written scores and tutors' scores in group 1 was 0.099 (p<0.001) and for group 2 was 0.305 (p<0.001). The higher correlation coefficient in the group where tutors received the PBL training reinforces the importance of tutor training before their participation in the PBL course.
Cross-cultural adaptation and validation of the Italian Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ).

PubMed

Bucci, Rosaria; Rongo, Roberto; Zito, Eugenio; Galeotti, Angela; Valletta, Rosa; D'Antò, Vincenzo

2015-03-01

To validate and cross-culturally adapt the Italian version of the Psychological Impact of Dental Aesthetics Questionnaire (PIDAQ) among Italian young adults. After translation, back translation, and cross-cultural adaptation of the English PIDAQ, a first version of the Italian questionnaire was pretested. The final Italian PIDAQ was administered to 598 subjects aged 18-30 years, along with two other instruments: the aesthetic component of the index of orthodontic treatment need (IOTN-AC) and the perception of occlusion scale (POS), which identified the self-reporting grade of malocclusion. Structural validity was assessed by means of factorial analysis, internal consistency was measured with Cronbach's alpha coefficient (α), convergent validity was assessed by means of Spearman correlation, and test-retest reliability was calculated with intra-class correlation coefficient (ICC) and standard measurement error. Criterion validity was evaluated by multivariate and univariate analysis of variance with Bonferroni post hoc tests. The α of the Italian PIDAQ domains ranged between 0.79 and 0.92. The ICC was between 0.81 and 0.90. The mean scores of each PIDAQ domain showed a statistically significant difference when analysed according to the IOTN-AC and POS scores. The satisfactory psychometric properties make PIDAQ a usable tool for future studies on oral health-related quality of life among Italian young adults.
The PEDro scale had acceptably high convergent validity, construct validity, and interrater reliability in evaluating methodological quality of pharmaceutical trials.

PubMed

Yamato, Tie Parma; Maher, Chris; Koes, Bart; Moseley, Anne

2017-06-01

The Physiotherapy Evidence Database (PEDro) scale has been widely used to investigate methodological quality in physiotherapy randomized controlled trials; however, its validity has not been tested for pharmaceutical trials. The aim of this study was to investigate the validity and interrater reliability of the PEDro scale for pharmaceutical trials. The reliability was also examined for the Cochrane Back and Neck (CBN) Group risk of bias tool. This is a secondary analysis of data from a previous study. We considered randomized placebo controlled trials evaluating any pain medication for chronic spinal pain or osteoarthritis. Convergent validity was evaluated by correlating the PEDro score with the summary score of the CBN risk of bias tool. The construct validity was tested using a linear regression analysis to determine the degree to which the total PEDro score is associated with treatment effect sizes, journal impact factor, and the summary score for the CBN risk of bias tool. The interrater reliability was estimated using the Prevalence and Bias Adjusted Kappa coefficient and 95% confidence interval (CI) for the PEDro scale and CBN risk of bias tool. Fifty-three trials were included, with 91 treatment effect sizes included in the analyses. The correlation between PEDro scale and CBN risk of bias tool was 0.83 (95% CI 0.76-0.88) after adjusting for reliability, indicating strong convergence. The PEDro score was inversely associated with effect sizes, significantly associated with the summary score for the CBN risk of bias tool, and not associated with the journal impact factor. The interrater reliability for each item of the PEDro scale and CBN risk of bias tool was at least substantial for most items (>0.60). The intraclass correlation coefficient for the PEDro score was 0.80 (95% CI 0.68-0.88), and for the CBN, risk of bias tool was 0.81 (95% CI 0.69-0.88). There was evidence for the convergent and construct validity for the PEDro scale when used to evaluate
Reliability and validity of the 12-item WHODAS 2.0 in patients with Kashin-Beck disease.

PubMed

Younus, Mohammad Imran; Wang, Di-Miao; Yu, Fang-Fang; Fang, Hua; Guo, Xiong

2017-09-01

The purpose of this study was to check the reliability and validity of the 12-item Chinese version of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) for the assessment of disability in patients with Kashin-Beck disease (KBD). We recruited 219 patients with KBD from the high-risk KBD area in the Shaanxi province, using stratified multistage random sampling. We assessed each patient using the Chinese version of the 12-item WHODAS 2.0 and the Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC). Statistical evaluations of the instruments consisted of Cronbach's alpha, intraclass correlation coefficient (ICC), confirmatory factor analysis (CFA), and Pearson's correlation coefficient. Cronbach's alpha and ICC for the six domains ranged from 0.704 to 0.906 and 0.690 to 0.852, respectively. A six-factor structure fits the data well (CFI = 0.967, TLI = 0.944, RMSEA = 0.08). Regarding convergent validity, the four domains of the 12-item WHODAS 2.0 (getting around, self-care, life activity, and participation) showed moderate-to-strong correlation for all three domains of the WOMAC (0.428 < |r| < 0.804). Regarding divergent validity, the two domains of the 12-item WHODAS 2.0 (understanding and communication, and getting along with people) showed weak correlation for the three domains of WOMAC (0.182 < |r| < 0.295). The Chinese version of 12-item WHODAS 2.0 questionnaire is a reliable and valid instrument when administered to KBD patients.
Correlation of heat transfer coefficient in quenching process using ABAQUS

NASA Astrophysics Data System (ADS)

Davare, Sandeep Kedarnath; Balachandran, G.; Singh, R. K. P.

2018-04-01

During the heat treatment by quenching in a liquid medium the convective heat transfer coefficient plays a crucial role in the extraction of heat. The heat extraction ultimately influences the cooling rate and hence the hardness and mechanical properties. A Finite Element analysis of quenching a simple flat copper sample with different orientation of sample and with different quenchant temperatures were carried out to check and verify the results obtained from the experiments. The heat transfer coefficient (HTC) was calculated from temperature history in a simple flat copper disc sample experimentally. This HTC data was further used as input to simulation software and the cooling curves were back calculated. The results obtained from software and using experimentation shows nearly consistent values.
Cross-cultural adaptation and validation of the Korean version of the neck disability index.

PubMed

Song, Kyung-Jin; Choi, Byung-Wan; Choi, Byung-Ryeul; Seo, Gyeu-Beom

2010-09-15

Validation of a translated, culturally adapted questionnaire. The purpose of this study is to translate and culturally adapt the Neck Disability Index (NDI) and to validate the use of the derived version in Korean patient. Although several valid measures exist for measurement of neck pain and functional impairment, these measures have yet been validated in Korean version. The NDI was linguistically translated into Korean, and prefinal version was assessed and modified by a pilot study. The reliability and validity of the derived Korean version was examined in 78 patients with degenerative cervical spine disease. Test-retest reliability, internal consistency, and construct validity were investigated by comparing Visual Analogue Scale (VAS) and Short Form Health Survey (SF-36) scores. Factor analysis of Korean NDI extracted 2 factors with eigenvalues >1. The intraclass-correlation coefficient of test-retest reliability was 0.93. Reliability, estimated by internal consistency, had a Cronbach alpha value of 0.82. The correlation between NDI and VAS scores was r = 0.49, and the correlation between NDI and SF-36 scores was r = -0.44. The physical health component score of SF-36 was highly correlated with NDI, and the correlation between VAS scores and the mental health component scores of SF-36 was high. The derived Korean version of the NDI was found to be a reliable and valid instrument for measuring disability in Korean patients with cervical problems. The authors recommend its use in future Korean clinical studies.
External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

DOE PAGES

Miles, Robin; Havstad, Mark; LeBlanc, Mary; ...

2015-09-15

External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m 2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.
Cross-cultural adaptation, validation, and reliability of the Michigan Hand Outcomes Questionnaire among Persian population.

PubMed

Ebrahimzadeh, Mohammad H; Birjandinejad, Ali; Kachooei, Amir Reza

2015-01-01

We aimed to validate a cross-culturally adapted version of the Persian Michigan Hand Outcomes Questionnaire (MHOQ). We followed the Beaton's guideline to translate the questionnaire to Persian. We administered the final version to 223 patients among which 79 patients returned 3 days later to respond to the Persian MHOQ for the second time. In the first visit, respondents also filled the Disabilities of the Arm Shoulder and Hand (DASH) and rated the pain based on the Visual Analogue Scale (VAS). Cronbach's alpha for the total MHOQ was 0.79 which showed good internal consistency. Intraclass correlation coefficient (ICC) for the total MHOQ was 0.84 which demonstrated good reliability between test and retest. The absolute correlation coefficient between total MHOQ and the DASH was as high as 0.74. Persian version of the MHOQ proved to be a reliable and valid instrument to be implemented among Persian population with the hand and wrist disorders.
Validity and reliability of an adapted arabic version of the long international physical activity questionnaire.

PubMed

Helou, Khalil; El Helou, Nour; Mahfouz, Maya; Mahfouz, Yara; Salameh, Pascale; Harmouche-Karaki, Mireille

2017-07-24

The International Physical Actvity Questionnaire (IPAQ) is a validated tool for physical activity assessment used in many countries however no Arabic version of the long-form of this questionnaire exists to this date. Hence, the aim of this study was to cross-culturally adapt and validate an Arabic version of the long International Physical Activity Questionnaire (AIPAQ) equivalent to the French version (F-IPAQ) in a Lebanese population. The guidelines for cross-cultural adaptation provided by the World Health Organization and the International Physical Activity Questionnaire committee were followed. One hundred fifty-nine students and staff members from Saint Joseph University of Beirut were randomly recruited to participate in the study. Items of the A-IPAQ were compared to those from the F-IPAQ for concurrent validity using Spearman's correlation coefficient. Content validity of the questionnaire was assessed using factor analysis for the A-IPAQ's items. The physical activity indicators derived from the A-IPAQ were compared with the body mass index (BMI) of the participants for construct validity. The instrument was also evaluated for internal consistency reliability using Cronbach's alpha and Intraclass Correlation Coefficient (ICC). Finally, thirty-one participants were asked to complete the A-IPAQ on two occasions three weeks apart to examine its test-retest reliability. Bland-Altman analyses were performed to evaluate the extent of agreement between the two versions of the questionnaire and its repeated administrations. A high correlation was observed between answers of the F-IPAQ and those of the A-IPAQ, with Spearman's correlation coefficients ranging from 0.91 to 1.00 (p < 0.05). Bland-Altman analysis showed a high level of agreement between the two versions with all values scattered around the mean for total physical activity (mean difference = 5.3 min/week, 95% limits of agreement = -145.2 to 155.8). Negative correlations were observed between
Development, validation, and administration of a treatment-satisfaction questionnaire for caregivers of dependent type 2 diabetic patients.

PubMed

García-Aparicio, Judit; Herrero-Herrero, José-Ignacio

2015-01-01

Satisfaction with treatment is considered a relevant factor for assessing results in clinical practice. However, when assessing satisfaction in dependent patients, the opinion of their caregivers becomes crucial, since implicit in satisfaction is the degree of caregiver involvement, of adherence to treatment, and lastly of better care of these patients. The purpose of this study was to develop, validate, and administer two versions of a specific questionnaire to assess satisfaction with blood glucose-lowering treatment in caregivers of dependent type 2 diabetic patients. This was an observational, descriptive, epidemiological study conducted in the Los Montalvos Internal Medicine Department at the University Hospital of Salamanca (Spain). Two versions of the questionnaire to assess caregivers' satisfaction with current treatment and after introducing changes in therapy were created and validated according to model procedures. Once validated, the questionnaires were implemented in 219 cases. Cronbach's α-coefficient, correlation between all the items, intraclass correlation coefficient, and correlation between the obtained scores and satisfaction with blood glucose levels all satisfied the standard for validation. Significant levels of correlation were observed between the degree of satisfaction and the number of daily administrations of the blood glucose-lowering medication (Spearman's r=-0.21, P<0.05). Caregivers of patients receiving more frequent administration of their antidiabetic medication prior to the change were more satisfied with the change (r=0.24, P<0.001). Similarly, significant correlation was found between the number of daily administrations for blood glucose-lowering medication after the change and the degree of satisfaction (r=-0.43, P<0.001). A useful novel instrument to assess caregivers' satisfaction was validated. When applied to our cohort of cases, the obtained data suggest that simplicity in antidiabetic therapy should be considered in the
Translation and validation of the German version of the Bournemouth Questionnaire for Neck Pain.

PubMed

Soklic, Marina; Peterson, Cynthia; Humphreys, B Kim

2012-01-25

Clinical outcome measures are important tools to monitor patient improvement during treatment as well as to document changes for research purposes. The short-form Bournemouth questionnaire for neck pain patients (BQN) was developed from the biopsychosocial model and measures pain, disability, cognitive and affective domains. It has been shown to be a valid and reliable outcome measure in English, French and Dutch and more sensitive to change compared to other questionnaires. The purpose of this study was to translate and validate a German version of the Bournemouth questionnaire for neck pain patients. German translation and back translation into English of the BQN was done independently by four persons and overseen by an expert committee. Face validity of the German BQN was tested on 30 neck pain patients in a single chiropractic practice. Test-retest reliability was evaluated on 31 medical students and chiropractors before and after a lecture. The German BQN was then assessed on 102 first time neck pain patients at two chiropractic practices for internal consistency, external construct validity, external longitudinal construct validity and sensitivity to change compared to the German versions of the Neck Disability Index (NDI) and the Neck Pain and Disability Scale (NPAD). Face validity testing lead to minor changes to the German BQN. The Intraclass Correlation Coefficient for the test-retest reliability was 0.99. The internal consistency was strong for all 7 items of the BQN with Cronbach α's of .79 and .80 for the pre and post-treatment total scores. External construct validity and external longitudinal construct validity using Pearson's correlation coefficient showed statistically significant correlations for all 7 scales of the BQN with the other questionnaires. The German BQN showed greater responsiveness compared to the other questionnaires for all scales. The German BQN is a valid and reliable outcome measure that has been successfully translated and

[Reliability and external validity of a questionnaire to assess the knowledge about risk and cardiovascular disease and in patients attending Spanish community pharmacies].

PubMed

Amariles, Pedro; Pino-Marín, Daniel; Sabater-Hernández, Daniel; García-Jiménez, Emilio; Roig-Sánchez, Inés; Faus, María José

2016-11-01

To determine the test-retest reliability of a questionnaire, with a validation preliminary, to assess knowledge of cardiovascular risk (CVR) and cardiovascular disease in patients attending community pharmacies in Spain. To complement the external validity, establishing the relationship between an educational activity and the increase in knowledge about CVR and cardiovascular disease. Sub-analysis of a controlled clinical study, EMDADER-CV, in which a questionnaire about knowledge concerning CVR was applied at 4 different times. Spanish Community Pharmacies. There were 323 patients in the control group, from the 640 who completed the study. Intraclass correlation coefficient to assess the reliability in 3 comparisons (post-educational activity with week 16, post-educational activity with week 32, and week 16 with week 32); and the non-parametric Friedman test to establish the relationship between an oral and written educational activity with increasing knowledge. For the 323 patients in the 3 comparisons, the intraclass correlation coefficient values were 0.624; 0.608 and 0.801, respectively (fair-good to excellent reliability). So, the Friedman test showed a statistically significant relationship between educational activity and increased knowledge (p < .0001). According to the intraclass correlation coefficient, the questionnaire aimed at assessing the knowledge on CVR and cardiovascular disease has a reliability between acceptable and excellent, which added to the previous validation, shows that the instrument meets the criteria of validity and reliability. Furthermore, the questionnaire showed the ability to relate an increase in knowledge with an educational intervention, feature that complements its external validity. Copyright © 2016 Elsevier España, S.L.U. All rights reserved.
Validity of a physical activity questionnaire in Shanghai.

PubMed

Peters, Tricia M; Shu, Xiao-Ou; Moore, Steven C; Xiang, Yong Bing; Yang, Gong; Ekelund, Ulf; Liu, Da-Ke; Tan, Yu-Ting; Ji, Bu-Tian; Schatzkin, Arthur S; Zheng, Wei; Chow, Wong Ho; Matthews, Charles E; Leitzmann, Michael F

2010-12-01

In large epidemiologic studies, physical activity (PA) is often assessed using PA questionnaires (PAQ). Because available PAQ may not capture the full range of PA in which urban Chinese adults engage, a PAQ was developed for this purpose. We examined the validity of this PAQ and the 1-yr stability of PA in 545 urban Shanghai adults. The PAQ was interview-administered twice, approximately 1 yr apart, and participants also wore an accelerometer and completed a PA-log for seven consecutive days every 3 months during the same year. The intraclass correlation coefficient (ICC) was used to evaluate the stability of PA across questionnaire administrations, and Spearman correlation coefficients (ρ) and mean differences and 95% limits of agreement were used to examine the validity of the questionnaire compared against accelerometry and the PA-log. When measured by accelerometry, estimates of time spent in moderate-to-vigorous PA were lower and estimates of time spent sedentary were higher than when self-reported on the PAQ (P < 0.001). Total PA (ICC = 0.65) and PA domains (ICC = 0.45-0.85) showed moderate to high stability across PAQ administrations. Total PA (ρ = 0.30), moderate-to-vigorous activity (ρ = 0.17), light activity (ρ = 0.36), and sedentary behavior (ρ = 0.16) assessed by PAQ and by accelerometry were significantly and positively correlated, and correlations of the PAQ with the PA-log (ρ = 0.36-0.85) were stronger than those observed with accelerometry. The PAQ significantly overestimated time spent in moderate-to-vigorous activity and underestimated time spent in light activity and sedentary behavior compared with accelerometry, but it performed well at ranking participants according to PA level.
Development and validation of the neck dissection impairment index: a quality of life measure.

PubMed

Taylor, Rodney J; Chepeha, Judith C; Teknos, Theodoros N; Bradford, Carol R; Sharma, Pramod K; Terrell, Jeffrey E; Hogikyan, Norman D; Wolf, Gregory T; Chepeha, Douglas B

2002-01-01

To validate a health-related quality-of-life (QOL) instrument for patients following neck dissection and to identify the factors that affect QOL following neck dissection. Cross-sectional validation study. The outpatient clinic of a tertiary care cancer center. Convenience sample of 54 patients previously treated for head and neck cancer who underwent a selective neck dissection or modified radical neck dissection (64 total neck dissections). Patients had a minimum postoperative convalescence of 11 months. Thirty-two underwent accessory nerve-sparing modified radical neck dissection, and 32 underwent selective neck dissection. A 10-item, self-report instrument, the Neck Dissection Impairment Index (NDII), was developed and validated. Reliability was evaluated with test-retest correlation and internal consistency using the Cronbach alpha coefficient. Convergent validity was assessed using the 36-Item Short-Form Health Survey (SF-36) and the Constant Shoulder Scale, a shoulder function test. Multiple variable regression was used to determine variables that most affected QOL following neck dissection The 10-item NDII test-retest correlation was 0.91 (P<.001) with an internal consistency Cronbach alpha coefficient of.95. The NDII correlated with the Constant Shoulder Scale (r = 0.85, P<.001) and with the SF-36 physical functioning (r = 0.50, P<.001) and role-physical functioning (r = 0.60, P<.001) domains. Using multiple variable regression, the variables that contributed most to QOL score were patient's age and weight, radiation treatment, and neck dissection type. The NDII is a valid, reliable instrument for assessing neck dissection impairment. Patient's age, weight, radiation treatment, and neck dissection type were important factors that affect QOL following neck dissection.
The Depressive Experiences Questionnaire: validity and psychological correlates in a clinical sample.

PubMed

Riley, W T; McCranie, E W

1990-01-01

This study sought to compare the original and revised scoring systems of the Depressive Experiences Questionnaire (DEQ) and to assess the construct validity of the Dependent and Self-Critical subscales of the DEQ in a clinically depressed sample. Subjects were 103 depressed inpatients who completed the DEQ, the Beck Depression Inventory (BDI), the Hopelessness Scale, the Automatic Thoughts Questionnaire (ATQ), the Rathus Assertiveness Schedule (RAS), and the Minnesota Multiphasic Personality Inventory (MMPI). The original and revised scoring systems of the DEQ evidenced good concurrent validity for each factor scale, but the revised system did not sufficiently discriminate dependent and self-critical dimensions. Using the original scoring system, self-criticism was significantly and positively related to severity of depression, whereas dependency was not, particularly for males. Factor analysis of the DEQ scales and the other scales used in this study supported the dependent and self-critical dimensions. For men, the correlation of the DEQ with the MMPI scales indicated that self-criticism was associated with psychotic symptoms, hostility/conflict, and a distress/exaggerated response set, whereas dependency did not correlate significantly with any MMPI scales. Females, however, did not exhibit a differential pattern of correlations between either the Dependency or the Self-Criticism scales and the MMPI. These findings suggest possible gender differences in the clinical characteristics of male and female dependent and self-critical depressive subtypes.
Translation and validation of the Cardiac Depression Scale to Arabic.

PubMed

Papasavvas, T; Al-Amin, H; Ghabrash, H F; Micklewright, D

2016-08-01

The Cardiac Depression Scale (CDS) has been designed to measure depressive symptoms in patients with heart disease. There is no Arabic version of the CDS. We translated and validated the CDS in an Arabic sample of patients with heart disease. Forward and back translation of the CDS was followed by assessment of cultural relevance and content validity. The Arabic version of the CDS (A-CDS) and the Arabic version of the Hospital Anxiety and Depression Scale (A-HADS) were then administered to 260 Arab in-patients with heart disease from 18 Arabic countries. Construct validity was assessed using exploratory factor analysis with polychoric correlations. Internal consistency was assessed using ordinal reliability alpha and item-to-factor polychoric correlations. Concurrent validity was assessed using Pearson's correlation coefficient between the A-CDS and the depression subscale of the A-HADS (A-HADS-D). Cultural relevance and content validity of the A-CDS were satisfactory. Exploratory factor analysis revealed three robust factors, without cross-loadings, that formed a single dimension. Internal consistency was high (ordinal reliability alpha for the total scale and the three factors were .94, .91, .86, and .87, respectively; item-to-factor correlations ranged from .77 to .91). Concurrent validity was high (r=.72). The A-CDS demonstrated a closer to normal distribution of scores than the A-HADS-D. Sensitivity and specificity of the A-CDS were not objectively assessed. The A-CDS appears to be a valid and reliable instrument to measure depressive symptoms in a representative sample of Arab in-patients with heart disease. Copyright © 2016 Elsevier B.V. All rights reserved.
Validation of the Polish Version of the Chronic Cough Quality of Life Questionnaire (Leicester Cough Questionnaire).

PubMed

Dąbrowska, Marta; Krakowiak, Karolina; Radlińska, Olga; Rybka, Aleksandra; Grabczak, Elżbieta M; Maskey-Warzęchowska, Marta; Korczyński, Piotr; Birring, Surinder S; Krenke, Rafał

2016-01-01

The Leicester Cough Questionnaire (LCQ) is one of the few specific quality-of-life questionnaires (QOLQ) dedicated to measuring the impact of chronic cough on patients' health/condition. The aim of the study was to validate the Polish version of the LCQ. The LCQ was translated forward and backward. The Polish version of the LCQ was tested on 35 patients suffering from chronic cough (23 women, median age 60 years, nonor ex-smokers, median cough duration of 23 weeks). Its validity was tested by comparison to a visual analogue scale (VAS) of cough intensity and other health questionnaires (hospital anxiety and depression scale - HADS, Euro-Quality of Life Questionnaire - EQ5D, St. George's Respiratory Questionnaire - SGRQ). The internal reliability of the Polish version of the LCQ was determined using the Cronbach alpha coefficient and its repeatability by the intraclass consistency coefficient. The translation of the LCQ into Polish was accepted by the author of the original LCQ. The Cronbach's alpha coefficient for total LCQ was 0.89, and reached 0.82, 0.86 and 0.78 for the physical, psychological and social domain, respectively. There were significant negative correlations between cough severity measured by VAS, the results of the EQ5D and SGRQ and the Polish version of the LCQ. The intraclass correlation coefficient of the test-retest reliability was significant (0.99). The Polish version of the LCQ has been validated and is a reliable tool to measure the impact of chronic cough on quality of life of patients with chronic cough.
Cross-Cultural adaption, validity and reliability of a Hindi version of the Corah’s Dental Anxiety Scale

PubMed Central

Jain, Meena; Tandon, Shourya; Sharma, Ankur; Jain, Vishal; Rani Yadav, Nisha

2018-01-01

Background: An appropriate scale to assess the dental anxiety of Hindi speaking population is lacking. This study, therefore, aims to evaluate the psychometric properties of Hindi version of one of the oldest dental anxiety scale, Corah’s Dental Anxiety Scale (CDAS) in Hindi speaking Indian adults. Methods: A total of 348 subjects from the outpatient department of a dental hospital in India participated in this cross-sectional study. The scale was cross-culturally adapted by forward and backward translation, committee review and pretesting method. The construct validity of the translated scale was explored with exploratory factor analysis. The correlation of the Hindi version of CDAS with visual analogue scale (VAS) was used to measure the convergent validity. Reliability was assessed through calculations of Cronbach’s alpha and intra class correlation 48 forms were completed for test-retest. Results: Prevalence of dental anxiety in the sample within the age range of 18-80 years was 85.63% [95% CI: 0.815-0.891]. The response rate was 100 %. Kaiser-Meyer-Olkin (KMO) test value was 0.776. After factor analysis, a single factor (dental anxiety) was obtained with 4 items.The single factor model explained 61% variance. Pearson correlation coefficient between CDASand VAS was 0.494. Test-retest showed the Cronbach’s alpha value of 0.814. The test-retest intraclass correlation coefficient of the total CDAS score was 0.881 [95% CI: 0.318-0.554]. Conclusion: Hindi version of CDAS is a valid and reliable scale to assess dental anxiety in Hindi speaking population. Convergent validity is well recognized but discriminant validity is limited and requires further study. PMID:29744307
Reliability and Validity of Athletes Disability Index Questionnaire.

PubMed

Noormohammadpour, Pardis; Hosseini Khezri, Alireza; Farahbakhsh, Farzin; Mansournia, Mohammad Ali; Smuck, Matthew; Kordi, Ramin

2018-03-01

The purpose of this study was to evaluate validity and reliability of a new proposed questionnaire for assessment of functional disability in athletes with low back pain (LBP). Validity and reliability study. Elite athletes participating in different fields of sports. Participants were 165 male and female athletes (between 12 and 50 years old) with LBP. Athlete Disability Index (ADI) Questionnaire which is developed by the authors for assessing LBP-related disability in athletes, Oswestry Disability Index (ODI), and the Roland-Morris Disability Questionnaire (RDQ). Self-reported responses were collected regarding LBP-related disability through ADI, ODI, and RDQ. The test-retest reliability was strong, and intraclass correlation value ranged between 0.74 and 0.94. The Cronbach alpha coefficient value of 0.91 (P < 0.001) demonstrated excellent internal consistency of the questionnaire. The correlation coefficient between ADI and ODI was r = 0.918 (P < 0.0001), between ADI and RDQ was r = 0.669 (P < 0.0001), and between ADI and visual analog scale was r = 0.626 (P < 0.001). According to ODI and RDQ, disability levels were mild in the large majority of subjects (91.5% and 86.0%, respectively). Alternatively, disability assessments by the ADI did not cluster at the mild level and ranged more broadly from mild to very high. The ADI is a reliable and valid instrument for assessing disability in athletes with LBP. Compared with the available LBP disability questionnaires used in the general population, ADI can more precisely stratify the disability levels of athletes due to LBP.
Sherwood correlation for dissolution of pooled NAPL in porous media

NASA Astrophysics Data System (ADS)

Aydin Sarikurt, Derya; Gokdemir, Cagri; Copty, Nadim K.

2017-11-01

The rate of interphase mass transfer from non-aqueous phase liquids (NAPLs) entrapped in the subsurface into the surrounding mobile aqueous phase is commonly expressed in terms of Sherwood (Sh) correlations that are expressed as a function of flow and porous media properties. Because of the lack of precise methods for the estimation of the interfacial area separating the NAPL and aqueous phases, most studies have opted to use modified Sherwood expressions that lump the interfacial area into the interphase mass transfer coefficient. To date, there are only two studies in the literature that have developed non-lumped Sherwood correlations; however, these correlations have undergone limited validation. In this paper controlled dissolution experiments from pooled NAPL were conducted. The immobile NAPL mass is placed at the bottom of a flow cell filled with porous media with water flowing horizontally on top. Effluent aqueous phase concentrations were measured for a wide range of aqueous phase velocities and for two different porous media. To interpret the experimental results, a two-dimensional pore network model of the NAPL dissolution kinetics and aqueous phase transport was developed. The observed effluent concentrations were then used to compute best-fit mass transfer coefficients. Comparison of the effluent concentrations computed with the two-dimensional pore network model to those estimated with one-dimensional analytical solutions indicates that the analytical model which ignores the transport in the lateral direction can lead to under-estimation of the mass transfer coefficient. Based on system parameters and the estimated mass transfer coefficients, non-lumped Sherwood correlations were developed and compared to previously published data. The developed correlations, which are a significant improvement over currently available correlations that are associated with large uncertainties, can be incorporated into future modeling studies requiring non-lumped Sh
Blinded versus unblinded estimation of a correlation coefficient to inform interim design adaptations

PubMed Central

Stallard, Nigel; Parsons, Nicholas; Todd, Susan; Friede, Tim

2016-01-01

Regulatory authorities require that the sample size of a confirmatory trial is calculated prior to the start of the trial. However, the sample size quite often depends on parameters that might not be known in advance of the study. Misspecification of these parameters can lead to under‐ or overestimation of the sample size. Both situations are unfavourable as the first one decreases the power and the latter one leads to a waste of resources. Hence, designs have been suggested that allow a re‐assessment of the sample size in an ongoing trial. These methods usually focus on estimating the variance. However, for some methods the performance depends not only on the variance but also on the correlation between measurements. We develop and compare different methods for blinded estimation of the correlation coefficient that are less likely to introduce operational bias when the blinding is maintained. Their performance with respect to bias and standard error is compared to the unblinded estimator. We simulated two different settings: one assuming that all group means are the same and one assuming that different groups have different means. Simulation results show that the naïve (one‐sample) estimator is only slightly biased and has a standard error comparable to that of the unblinded estimator. However, if the group means differ, other estimators have better performance depending on the sample size per group and the number of groups. PMID:27886393
Standardized uptake value and apparent diffusion coefficient of endometrial cancer evaluated with integrated whole-body PET/MR: Correlation with pathological prognostic factors.

PubMed

Shih, I-Lun; Yen, Ruoh-Fang; Chen, Chi-An; Chen, Bang-Bin; Wei, Shwu-Yuan; Chang, Wen-Chun; Sheu, Bor-Ching; Cheng, Wen-Fang; Tseng, Yao-Hui; Chen, Xin-Jia; Chen, Chi-Hau; Wei, Lin-Hung; Chiang, Ying-Cheng; Torng, Pao-Ling; Yen, Men-Luh; Shih, Tiffany Ting-Fang

2015-12-01

To evaluate the correlation between maximum standardized uptake value (SUVmax ) and minimum apparent diffusion coefficient (ADCmin ) of endometrial cancer derived from an integrated positron emission tomography / magnetic resonance (PET/MR) system and to determine their correlation with pathological prognostic factors. This prospective study was approved by the Institutional Review Board of the hospital, and informed consent was obtained. Between April and December 2014, 47 consecutive patients with endometrial cancer were enrolled and underwent simultaneous PET/MR examinations before surgery. Thirty-six patients with measurable tumors on PET/MR were included for image analysis. Pearson's correlation coefficient was used to evaluate the correlation between SUVmax and ADCmin of the tumors. The Mann-Whitney U-test was utilized to evaluate relationships between these two imaging biomarkers and pathological prognostic factors. The mean SUVmax and ADCmin were 14.7 ± 7.1 and 0.48 ± 0.13 × 10(-3) mm(2) /s, respectively. A significant inverse correlation was found between SUVmax and ADCmin (r = -0.53; P = 0.001). SUVmax was significantly higher in tumors with advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05). ADCmin was lower in tumors with higher grade, advanced stage, and cervical invasion (P < 0.05). The ratio of SUVmax to ADCmin was higher in tumors with higher grade, advanced stage, deep myometrial invasion, cervical invasion, lymphovascular space involvement, and lymph node metastasis (P < 0.05). SUVmax and ADCmin of endometrial cancer derived from integrated PET/MR are inversely correlated and are associated with pathological prognostic factors. © 2015 Wiley Periodicals, Inc.
Dynamic Time Warping compared to established methods for validation of musculoskeletal models.

PubMed

Gaspar, Martin; Welke, Bastian; Seehaus, Frank; Hurschler, Christof; Schwarze, Michael

2017-04-11

By means of Multi-Body musculoskeletal simulation, important variables such as internal joint forces and moments can be estimated which cannot be measured directly. Validation can ensued by qualitative or by quantitative methods. Especially when comparing time-dependent signals, many methods do not perform well and validation is often limited to qualitative approaches. The aim of the present study was to investigate the capabilities of the Dynamic Time Warping (DTW) algorithm for comparing time series, which can quantify phase as well as amplitude errors. We contrast the sensitivity of DTW with other established metrics: the Pearson correlation coefficient, cross-correlation, the metric according to Geers, RMSE and normalized RMSE. This study is based on two data sets, where one data set represents direct validation and the other represents indirect validation. Direct validation was performed in the context of clinical gait-analysis on trans-femoral amputees fitted with a 6 component force-moment sensor. Measured forces and moments from amputees' socket-prosthesis are compared to simulated forces and moments. Indirect validation was performed in the context of surface EMG measurements on a cohort of healthy subjects with measurements taken of seven muscles of the leg, which were compared to simulated muscle activations. Regarding direct validation, a positive linear relation between results of RMSE and nRMSE to DTW can be seen. For indirect validation, a negative linear relation exists between Pearson correlation and cross-correlation. We propose the DTW algorithm for use in both direct and indirect quantitative validation as it correlates well with methods that are most suitable for one of the tasks. However, in DV it should be used together with methods resulting in a dimensional error value, in order to be able to interpret results more comprehensible. Copyright © 2017 Elsevier Ltd. All rights reserved.
Inertial Measurement Units for Clinical Movement Analysis: Reliability and Concurrent Validity

PubMed Central

Nicholas, Kevin; Sparkes, Valerie; Sheeran, Liba; Davies, Jennifer L

2018-01-01

The aim of this study was to investigate the reliability and concurrent validity of a commercially available Xsens MVN BIOMECH inertial-sensor-based motion capture system during clinically relevant functional activities. A clinician with no prior experience of motion capture technologies and an experienced clinical movement scientist each assessed 26 healthy participants within each of two sessions using a camera-based motion capture system and the MVN BIOMECH system. Participants performed overground walking, squatting, and jumping. Sessions were separated by 4 ± 3 days. Reliability was evaluated using intraclass correlation coefficient and standard error of measurement, and validity was evaluated using the coefficient of multiple correlation and the linear fit method. Day-to-day reliability was generally fair-to-excellent in all three planes for hip, knee, and ankle joint angles in all three tasks. Within-day (between-rater) reliability was fair-to-excellent in all three planes during walking and squatting, and poor-to-high during jumping. Validity was excellent in the sagittal plane for hip, knee, and ankle joint angles in all three tasks and acceptable in frontal and transverse planes in squat and jump activity across joints. Our results suggest that the MVN BIOMECH system can be used by a clinician to quantify lower-limb joint angles in clinically relevant movements. PMID:29495600
Development and validation of a beverage and snack questionnaire for use in evaluation of school nutrition policies.

PubMed

Neuhouser, Marian L; Lilley, Sonya; Lund, Anne; Johnson, Donna B

2009-09-01

School nutrition policies limiting access to sweetened beverages, candy, and salty snacks have the potential to improve the health of children. To effectively evaluate policy success, appropriate and validated dietary assessment instruments are needed. The objective of this study was to develop and validate a beverage and snack questionnaire suitable for use among young adolescents. A new 19-item Beverage and Snack Questionnaire (BSQ) was administered to middle school students on two occasions, 2 weeks apart, to measure test-retest reliability. The questionnaire inquired about frequency of consumption, both at school and away from school, of soft drinks, salty snacks, sweets, milk, and fruits and vegetables. Students also completed 4-day food records. To assess validity, food-record data were compared with BSQ data. Forty-six students of diverse backgrounds from metropolitan Seattle, WA, participated in this study. Participants answered the BSQ during class time and completed the food record at home. Pearson correlation coefficients assessed test-retest reliability and validity. Using frequency per week data, the test-retest reliability coefficients were r=0.85 for fruits and vegetables consumed at school and r=0.74 and r=0.72 for beverages and sweets/snacks, respectively, consumed at school. Correlations ranged from r=0.73 to 0.77 for foods consumed outside of school. Compared with the criterion food record, validity coefficients were very good: r=0.69 to 0.71 for foods consumed at school and r=0.63 to 0.70 for foods consumed away from school. The validity coefficients for the 19 individual food items ranged from r=0.56 to 0.87. This easy-to-administer 19-item questionnaire captures data on sugar-sweetened beverages, salty snacks, sweets, milk, and fruit and vegetables as well as a more lengthy and expensive food record does. The BSQ can be used by nutrition researchers and practitioners to accurately evaluate student consumption of foods that are the focus of
Construct validity of the Free and Cued Selective Reminding Test in older adults with memory complaints.

PubMed

Clerici, Francesca; Ghiretti, Roberta; Di Pucchio, Alessandra; Pomati, Simone; Cucumo, Valentina; Marcone, Alessandra; Vanacore, Nicola; Mariani, Claudio; Cappa, Stefano Francesco

2017-06-01

The Free and Cued Selective Reminding Test (FCSRT) is the memory test recommended by the International Working Group on Alzheimer's disease (AD) for the detection of amnestic syndrome of the medial temporal type in prodromal AD. Assessing the construct validity and internal consistency of the Italian version of the FCSRT is thus crucial. The FCSRT was administered to 338 community-dwelling participants with memory complaints (57% females, age 74.5 ± 7.7 years), including 34 with AD, 203 with Mild Cognitive Impairment, and 101 with Subjective Memory Impairment. Internal Consistency was estimated using Cronbach's alpha coefficient. To assess convergent validity, five FCSRT scores (Immediate Free Recall, Immediate Total Recall, Delayed Free Recall, Delayed Total Recall, and Index of Sensitivity of Cueing) were correlated with three well-validated memory tests: Story Recall, Rey Auditory Verbal Learning test, and Rey Complex Figure (RCF) recall (partial correlation analysis). To assess divergent validity, a principal component analysis (an exploratory factor analysis) was performed including, in addition to the above-mentioned memory tasks, the following tests: Word Fluencies, RCF copy, Clock Drawing Test, Trail Making Test, Frontal Assessment Battery, Raven Coloured Progressive Matrices, and Stroop Colour-Word Test. Cronbach's alpha coefficients for immediate recalls (IFR and ITR) and delayed recalls (DFR and DTR) were, respectively, .84 and .81. All FCSRT scores were highly correlated with those of the three well-validated memory tests. The factor analysis showed that the FCSRT does not load on the factors saturated by non-memory tests. These findings indicate that the FCSRT has a good internal consistency and has an excellent construct validity as an episodic memory measure. © 2015 The British Psychological Society.
Ecology of Floristic Quality Assessment: testing for correlations between coefficients of conservatism, species traits and mycorrhizal responsiveness

PubMed Central

Koziol, Liz; Bever, James D

2018-01-01

Abstract Many plant species are limited to habitats relatively unaffected by anthropogenic disturbance, so protecting these undisturbed habitats is essential for plant conservation. Coefficients of conservatism (C values) were developed as indicators of a species’ sensitivity to anthropogenic disturbance, and these values are used in Floristic Quality Assessment as a means of assessing natural areas and ecological restoration. However, assigning of these values is subjective and improved quantitative validation of C values is needed. We tested whether there are consistent differences in life histories between species with high and low C values. To do this, we grew 54 species of tallgrass prairie plants in a greenhouse and measured traits that are associated with trade-offs on the fast-slow continuum of life-history strategies. We also grew plants with and without mycorrhizal fungi as a test of these species’ reliance on this mutualism. We compared these traits and mycorrhizal responsiveness to C values. We found that six of the nine traits we measured were correlated with C values, and together, traits predicted up to 50 % of the variation in C values. Traits including fast growth rates and greater investment in reproduction were associated with lower C values, and slow growth rates, long-lived leaves and high root:shoot ratios were associated with higher C values. Additionally, plants with high C values and a slow life history were more responsive to mutualisms with mycorrhizal fungi. Overall, our results connect C values with life-history trade-offs, indicating that high C value species tend to share a suite of traits associated with a slow life history. PMID:29383232
Toddler physical activity study: laboratory and community studies to evaluate accelerometer validity and correlates.

PubMed

Hager, Erin R; Gormley, Candice E; Latta, Laura W; Treuth, Margarita S; Caulfield, Laura E; Black, Maureen M

2016-09-06

Toddlerhood is an important age for physical activity (PA) promotion to prevent obesity and support a physically active lifestyle throughout childhood. Accurate assessment of PA is needed to determine trends/correlates of PA, time spent in sedentary, light, or moderate-vigorous PA (MVPA), and the effectiveness of PA promotion programs. Due to the limited availability of objective measures that have been validated and evaluated for feasibility in community studies, it is unclear which subgroups of toddlers are at the highest risk for inactivity. Using Actical ankle accelerometry, the objectives of this study are to develop valid thresholds, examine feasibility, and examine demographic/ anthropometric PA correlates of MVPA among toddlers from low-income families. Two studies were conducted with toddlers (12-36 months). Laboratory Study (n = 24)- Two Actical accelerometers were placed on the ankle. PA was observed using the Child Activity Rating Scale (CARS, prescribed activities). Analyses included device equivalence reliability (correlation: activity counts of two Acticals), criterion-related validity (correlation: activity counts and CARS ratings), and sensitivity/specificity for thresholds. Community Study (n = 277, low-income mother-toddler dyads recruited)- An Actical was worn on the ankle for > 7 days (goal >5, 24-h days). Height/weight was measured. Mothers reported demographics. Analyses included frequencies (feasibility) and stepwise multiple linear regression (sMLR). Laboratory Study- Acticals demonstrated reliability (r = 0.980) and validity (r = 0.75). Thresholds demonstrated sensitivity (86 %) and specificity (88 %). Community Study- 86 % wore accelerometer, 69 % had valid data (mean = 5.2 days). Primary reasons for missing/invalid data: refusal (14 %) and wear-time ≤2 days (11 %). The MVPA threshold (>2200 cpm) yielded 54 min/day. In sMLR, MVPA was associated with age (older > younger, β = 32.8, p < 0
Validity and reliability of the Physical Activity Scale for the Elderly (PASE) in Japanese elderly people.

PubMed

Hagiwara, Akiko; Ito, Naomi; Sawai, Kazuhiko; Kazuma, Keiko

2008-09-01

In Japan, there are no valid and reliable physical activity questionnaires for elderly people. In this study, we translated the Physical Activity Scale for the Elderly (PASE) into Japanese and assessed its validity and reliability. Three hundred and twenty-five healthy and elderly subjects over 65 years were enrolled. Concurrent validity was evaluated by Spearman's rank correlation coefficient between PASE scores and an accelerometer (waking steps and energy expenditure), a physical activity questionnaire for adults in general (the Japan Arteriosclerosis Longitudinal Study Physical Activity Questionnaire, JALSPAQ), grip strength, mid-thigh muscle area per bodyweight, static valance and bodyfat percentage. Reliability was evaluated by the test-retest method over a period of 3-4 weeks. The mean PASE score in this study was 114.9. The PASE score was significantly correlated with walking steps (rho = 0.17, P = 0.014), energy expenditure (rho = 0.16, P = 0.024), activity measured with the JALSPAQ (rho = 0.48, P < 0.001), mid-thigh muscle area per bodyweight (rho = 0.15, P = 0.006) and static balance (rho = 0.19, P = 0.001). The proportion of consistency in the response between the first and second surveys was adequately high. The intraclass correlation coefficient for the PASE score was 0.65. The Japanese version of PASE was shown to have acceptable validity and reliability. The PASE is useful to measure the physical activity of elderly people in Japan.
[Analysis of reliability and validity of the Chinese Version of Dizziness Handicap Inventory (DHI)].

PubMed

Zhang, Yi; Liu, Bo; Wang, Yongjun; Zhou, Yun; Wang, Rui; Gong, Jing; Peng, Xiaoxia

2015-09-01

To investigate the reliability and validity of the Chinese Version of Dizziness Handicap Inventory (DHI). Cross-cultural adaptation of health-related quality of life measures was used for translating the DHI to Chinese version. The DHI contains 7 physical, 9 emotional, and 9 functional questions.The patients scored the DHI straightforward. Then the scores of the total scale and each subscales were calculated and evaluated.Three hundred and sixty-six dizzy patients,116 males and 250 females, aged from 14 to 79 years, were included in the research and finished the questionnaire of the evaluation.SPSS 13.0 was used for statistical analysis. Reliability: Cronbach α values for the total and subscale of DHI were 0.751-0.912. The reliability coefficients were 0.877-0.921 (P < 0.001). the correlation coefficients between the total scale and three subscale were 0.815-0.934 (P < 0.001). The correlation coefficients of the scores internal the subscale were higher than between the other subscale (r = 0.446-0.781). Common factor analysis provides 5 factors. The cumulative variance ratio was 54.5%. The component of each item was over 0.4. Chinese version of DHI has good reliability and validity, which can be used to evaluate the dizzy patients.
Validity and reliability of a pilot scale for assessment of multiple system atrophy symptoms.

PubMed

Matsushima, Masaaki; Yabe, Ichiro; Takahashi, Ikuko; Hirotani, Makoto; Kano, Takahiro; Horiuchi, Kazuhiro; Houzen, Hideki; Sasaki, Hidenao

2017-01-01

Multiple system atrophy (MSA) is a rare progressive neurodegenerative disorder for which brief yet sensitive scale is required in order for use in clinical trials and general screening. We previously compared several scales for the assessment of MSA symptoms and devised an eight-item pilot scale with large standardized response mean [handwriting, finger taps, transfers, standing with feet together, turning trunk, turning 360°, gait, body sway]. The aim of the present study is to investigate the validity and reliability of a simple pilot scale for assessment of multiple system atrophy symptoms. Thirty-two patients with MSA (15 male/17 female; 20 cerebellar subtype [MSA-C]/12 parkinsonian subtype [MSA-P]) were prospectively registered between January 1, 2014 and February 28, 2015. Patients were evaluated by two independent raters using the Unified MSA Rating Scale (UMSARS), Scale for Assessment and Rating of Ataxia (SARA), and the pilot scale. Correlations between UMSARS, SARA, pilot scale scores, intraclass correlation coefficients (ICCs), and Cronbach's alpha coefficients were calculated. Pilot scale scores significantly correlated with scores for UMSARS Parts I, II, and IV as well as with SARA scores. Intra-rater and inter-rater ICCs and Cronbach's alpha coefficients remained high (> 0.94) for all measures. The results of the present study indicate the validity and reliability of the eight-item pilot scale, particularly for the assessment of symptoms in patients with early state multiple system atrophy.

CROSS-CULTURAL ADAPTATION AND VALIDATION OF THE ITCHING SEVERITY SCALE IN CHILDREN AND ADOLESCENTS WITH ATOPIC DERMATITIS

PubMed Central

Bruscky, Dayanne Mota Veloso; Melo, Ana Caroline Cavalcanti Dela Bianca; Sarinho, Emanuel Sávio Cavalcanti

2017-01-01

ABSTRACT Objective: To translate, adapt and validate the Itch Severity Scale to a Brazilian version (ISS-Ped) in order to measure the severity of pruritus in children and adolescents with atopic dermatitis. Methods: This is a methodological study of validation of an instrument following recommended protocols. The translated version was evaluated by a group of experts including one professional with experience in instrument validation, three English teachers, one linguistics teacher and seven allergists. After this, the scale was applied to 42 parents of children aged between 2 and 18 years old with atopic dermatitis, and 42 parents of children without pruritic diseases. Results were evaluated according to the severity of atopic dermatitis and disease control, and they were compared between groups with and without atopic dermatitis. Results: More than 90% of the questions were clear to the parents. The ISS-Ped showed a strong positive correlation with the severity of atopic dermatitis (Pearson: 0.74; p<0.001) and a good correlation with the control of dermatitis (point-biserial correlation coefficient: 0.65; p<0.001). The scale showed excellent internal consistency (Cronbach’s α: 0.96) and adequate test and retest agreement (95% confidence interval of intraclass correlation coefficient: 0.89-0.99; p<0.001). Conclusions: The ISS-Ped is a feasible, valid, reliable and satisfactorily equivalent. The translated scale was appropriate to assess the severity of itching in children and adolescents with eczema, allowing comparisons in the clinical practice and in the research setting. PMID:28977301
Use of the Method of Triads in the Validation of Sodium and Potassium Intake in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil)

PubMed Central

Pereira, Taísa Sabrina Silva; Cade, Nágela Valadão; Mill, José Geraldo; Sichieri, Rosely; Molina, Maria del Carmen Bisi

2016-01-01

Introduction Biomarkers are a good choice to be used in the validation of food frequency questionnaire due to the independence of their random errors. Objective To assess the validity of the potassium and sodium intake estimated using the Food Frequency Questionnaire ELSA-Brasil. Subjects/Methods A subsample of participants in the ELSA-Brasil cohort was included in this study in 2009. Sodium and potassium intake were estimated using three methods: Semi-quantitative food frequency questionnaire, 12-hour nocturnal urinary excretion and three 24-hour food records. Correlation coefficients were calculated between the methods, and the validity coefficient was calculated using the method of triads. The 95% confidence intervals for the validity coefficient were estimated using bootstrap sampling. Exact and adjacent agreement and disagreement of the estimated sodium and potassium intake quintiles were compared among three methods. Results The sample consisted of 246 participants, aged 53±8 years, 52% of women. Validity coefficient for sodium were considered weak (рfood frequency questionnaire actual intake = 0.37 and рbiomarker actual intake = 0.21) and moderate (рfood records actual intake 0.56). The validity coefficient were higher for potassium (рfood frequency questionnaire actual intake = 0.60; рbiomarker actual intake = 0.42; рfood records actual intake = 0.79). Conclusions: The Food Frequency Questionnaire ELSA-Brasil showed good validity in estimating potassium intake in epidemiological studies. For sodium validity was weak, likely due to the non-quantification of the added salt to prepared food. PMID:28030625
Use of the Method of Triads in the Validation of Sodium and Potassium Intake in the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

PubMed

Pereira, Taísa Sabrina Silva; Cade, Nágela Valadão; Mill, José Geraldo; Sichieri, Rosely; Molina, Maria Del Carmen Bisi

2016-01-01

Biomarkers are a good choice to be used in the validation of food frequency questionnaire due to the independence of their random errors. To assess the validity of the potassium and sodium intake estimated using the Food Frequency Questionnaire ELSA-Brasil. A subsample of participants in the ELSA-Brasil cohort was included in this study in 2009. Sodium and potassium intake were estimated using three methods: Semi-quantitative food frequency questionnaire, 12-hour nocturnal urinary excretion and three 24-hour food records. Correlation coefficients were calculated between the methods, and the validity coefficient was calculated using the method of triads. The 95% confidence intervals for the validity coefficient were estimated using bootstrap sampling. Exact and adjacent agreement and disagreement of the estimated sodium and potassium intake quintiles were compared among three methods. The sample consisted of 246 participants, aged 53±8 years, 52% of women. Validity coefficient for sodium were considered weak (рfood frequency questionnaire actual intake = 0.37 and рbiomarker actual intake = 0.21) and moderate (рfood records actual intake 0.56). The validity coefficient were higher for potassium (рfood frequency questionnaire actual intake = 0.60; рbiomarker actual intake = 0.42; рfood records actual intake = 0.79). Conclusions: The Food Frequency Questionnaire ELSA-Brasil showed good validity in estimating potassium intake in epidemiological studies. For sodium validity was weak, likely due to the non-quantification of the added salt to prepared food.
Correlation between incidences of self-inflicted burns and means of inbreeding coefficients, an ecologic study.

PubMed

Saadat, Mostafa; Zendeh-Boodi, Zahra

2006-09-01

The aim of the study is to obtain more insight into the possible association between consanguinity and the incidence of deliberate self-burning. Data were obtained by analysis of medical records of patients hospitalized in two referral burn centers: Chormy Burn Center (Bushehr Province, south of Iran) from March 21, 1998, through March 20, 2004, and Shahid Sadoqi Center of Burns and Injuries (Yazd Province, center of Iran) from March 21, 2000, through March 20, 2004. The incidence of suicidal burns was 6.51 and 2.32/100,000 person-years for Bushehr and Yazd Provinces, respectively. The observed sex ratio of patients in both centers indicated there was a female predominance in patients with self-inflicted burns. Using patients' home addresses, patients were sorted into 16 cities. The incidence of suicide by self-burning ranged from 0.80 (for Tabas, located in Yazd Province) to 12.60/100,000 person-years (for Dilam, located in Bushehr Province). The coefficient of inbreeding defines the probability that an individual received both alleles of a pair from an identical ancestral source. There was a significant correlation between incidences of suicidal burns and mean coefficient of inbreeding (r = 0.782, df = 14, p < 0.001). In addition to other factors, consanguineous marriage may be a risk factor that influences the incidence of suicidal burns in a population.
Arabic cross cultural adaptation and validation of the National Institutes of Health Stroke Scale.

PubMed

Hussein, Haitham M; Abdel Moneim, Amr; Emara, Tamer; Abd-Elhamid, Yousry A; Salem, Haitham H; Abd-Allah, Foad; Farrag, Mohammad A; Tork, M Amir; Shalash, Ali S; Ezz El Dein, Khaled H; Osman, Gamaleldin; Georgy, Shady S; Ghali, Peter G; Lyden, Patrick D; Moustafa, Ramez R

2015-10-15

The National Institutes of Health Stroke Scale (NIHSS), the most commonly used tool to quantify neurological deficit in acute stroke, was initially developed in English. We present our experience in developing and validating an Arabic version of the NIHSS (arNIHSS). In 6months, 137 patients were recruited (mean age±standard deviation 62±12years; 48 women). For interrater agreement, weighted kappa value ranged from 0.36 to 0.66 and intraclass correlation coefficient (ICC) for the whole scale was excellent at 0.95 (95% confidence interval [CI] 0.94-0.97). For intrarater agreement, weighted kappa ranged from 0.52 to 1.0 and the ICC was 0.94 (95% CI 0.87-0.98). The construct validity of the arNIHSS is demonstrated by its correlation with the DWI-ASPECT and the 3months mRS score (Spearman correlation -0.46 and 0.58 respectively; P<0.001 for both). We developed and validated a culturally adapted Arabic version of the NIHSS. Further validation in other Arab countries is recommended. Copyright © 2015 Elsevier B.V. All rights reserved.
Relative validity of a food frequency questionnaire to identify dietary patterns in an adult Mexican population.

PubMed

Denova-Gutiérrez, Edgar; Tucker, Katherine L; Salmerón, Jorge; Flores, Mario; Barquera, Simón

2016-01-01

To examine the validity of a semi-quantitative food frequency questionnaire (SFFQ) to identify dietary patterns in an adult Mexican population. A 140-item SFFQ and two 24-hour dietary recalls (24DRs) were administered. Foods were categorized into 29 food groups used to derive dietary patterns via factor analysis. Pearson and intraclass correlations coefficients between dietary pattern scores identified from the SFFQ and 24DRs were assessed. Pattern 1 was high in snacks, fast food, soft drinks, processed meats and refined grains; pattern 2 was high in fresh vegetables, fresh fruits, and dairy products; and pattern 3 was high in legumes, eggs, sweetened foods and sugars. Pearson correlation coefficients between the SFFQ and the 24DRs for these patterns were 0.66 (P<0.001), 0.41 (P<0.001) and 0.29 (P=0.193) respectively. Our data indicate reasonable validity of the SFFQ, using factor analysis, to derive major dietary patterns in comparison with two 24DR.
[Reliability and validity of Parkinson's disease sleep scale-Chinese version in the south west of China].

PubMed

Zhang, J H; Peng, R; Du, Y; Mou, Y; Li, N N; Cheng, L

2016-11-08

Objective: To evaluate the reliability and validity of Parkinson's disease sleep scale-Chinese version (CPDSS) through a study of a large PD population in southwest China, and to explore the prevalence and characteristics of sleep disorders in Parkinson's disease (PD) patients from southwest China. Methods: A total of 544 PD patients and 220 control subjects were enrolled in our study. Demographic data, CPDSS, ESS, PDQ39, HAMD and H-Y stage were assessed in all subjects. Statistical description, Cronbach's alpha coefficient, intra-class correlation coefficient ( ICC ), Spearman rank correlation coefficient and Mann-Whitney U test were used for statistical analyses. Result: The Cronbach's alpha coefficient for CPDSS was 0.79, ICC of the total scale was 0.94 and ICC of each item ranged from 0.73 to 0.97. The factor analysis yielded a five-factor solution, which explained 63.4% of the total variance. Total and each item scores of CPDSS in PD patients were lower than those in healthy controls. 69.3% of PD patients had sleep disorder, while prevalence in the control group was only 29.6%. Negative correlation was found between CPDSS and ESS. Daytime sleepiness was the most common factor (35.9%) leading to sleep disorders. The sleep disorders of PD patients in Southwest China were significantly related with the course of disease, the severity of disease, the quality of life, depression, cognitive level and motor symptoms. Conclusion: CPDSS has good feasibility, reliability and validity in PD population from southwest China. CPDSS is considered as an effective tool for the assessment of sleep disorder in PD patients.
Lecture Notes on Criticality Safety Validation Using MCNP & Whisper

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Forrest B.; Rising, Michael Evan; Alwin, Jennifer Louise

Training classes for nuclear criticality safety, MCNP documentation. The need for, and problems surrounding, validation of computer codes and data area considered first. Then some background for MCNP & Whisper is given--best practices for Monte Carlo criticality calculations, neutron spectra, S(α,β) thermal neutron scattering data, nuclear data sensitivities, covariance data, and correlation coefficients. Whisper is computational software designed to assist the nuclear criticality safety analyst with validation studies with the Monte Carlo radiation transport package MCNP. Whisper's methodology (benchmark selection – C k's, weights; extreme value theory – bias, bias uncertainty; MOS for nuclear data uncertainty – GLLS) and usagemore » are discussed.« less
Evaluation of generalized heat-transfer coefficients in pilot AFBC units

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grewal, N.S.

Experimental data for heat transfer rates as obtained in a 0.209m/sup 2/ AFBC unit at the GFETC is examined in the light of the existing four correlations for heat transfer coefficient between an immersed staggered array of horizontal tubes and a gas-solid fluidized bed. The predicted values of heat transfer coefficient from the correlations proposed by Grewal and Bansal are found to be in good agreement with the experimental values of heat transfer coefficient when the contribution due to radiation is also included.
Evaluation of generalized heat transfer coefficients in pilot AFBC units

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grewal, N.S.

Experimental data for heat transfer rates as obtained in a 0.209m/sup 2/ AFBC unit at the GFETC is examined in the light of the existing four correlations for heat transfer coefficient between an immersed staggered array of horizontal tubes and a gas-solid fluidized bed. The predicted values of heat transfer coefficient from the correlations proposed by Grewal and Bansal are found to be in good agreement with the experimental values of heat transfer coefficient when the contribution due to radiation is also included.
Reliability and Validity of the Turkish Version of the Gastrointestinal Symptom Rating Scale.

PubMed

Turan, Nuray; Aşt, Türkinaz Atabek; Kaya, Nurten

The purpose of this methodological study is to investigate the validity and reliability of the Turkish version of the Gastrointestinal Symptom Rating Scale (GSRS). The scale was adapted to the Turkish language via backward translation. Content validity was examined by referring to experts. Reliability was examined via test-retest reliability and internal consistency, and validity was examined with divergent and convergent validity. The Epworth Sleepiness Scale (ESS) and the Marlowe-Crowne Social Desirability Scale (MCSDS) were used for divergent validity. As for convergent validity, the Constipation Severity Instrument (CSI) and the Patient Assessment of Constipation Quality of Life Scale (PAC-QOLQ) were utilized. The relationship between the GSRS and the health-related quality of life (36-item short-form health survey [SF-36]) was also analyzed. The study population consisted of patients in orthopedic clinic who volunteered to participate. Test-retest reliability was examined with the participation of 30 patients; internal consistency and validity were examined with 150 patients. Test-retest reliability correlation coefficients of the GSRS varied from 0.39 to 0.87 for all items. For internal consistency, the GSRS's item total correlation was found to be 0.17-0.67, and Cronbach α was 0.82 for all items. There was a positive linear significant correlation between the GSRS, CSI, and PAC-QOLQ. There was no significant correlation between the GSRS, MCSDS, and ESS. Higher GSRS scores inversely correlated with general quality of life (SF-36). The Turkish version of the GSRS has been found to be a reliable and valid instrument for assessing patients' gastrointestinal symptoms. Therefore, this instrument can be confidently used with Turkish individuals.
Cross-Cultural Adaptation, Validity, and Reliability of the Persian Version of the Orebro Musculoskeletal Pain Screening Questionnaire.

PubMed

Shafeei, Asrin; Mokhtarinia, Hamid Reza; Maleki-Ghahfarokhi, Azam; Piri, Leila

2017-08-01

Observational study. To cross-culturally translate the Orebro Musculoskeletal Pain Screening Questionnaire (OMPQ) into Persian and then evaluate its psychometric properties (reliability, validity, ceiling, and flooring effects). To the authors' knowledge, prior to this study there has been no validated instrument to screen the risk of chronicity in Persian-speaking patients with low back pain (LBP) in Iran. The OMPQ was specifically developed as a self-administered screening tool for assessing the risk of LBP chronicity. The forward-backward translation method was used for the translation and cross-cultural adaptation of the original questionnaire. In total, 202 patients with subacute LBP completed the OMPQ and the pain disability questionnaire (PDQ), which was used to assess convergent validity. 62 patients completed the OMPQ a week later as a retest. Slight changes were made to the OMPQ during the translation/cultural adaptation process; face validity of the Persian version was obtained. The Persian OMPQ showed excellent test-retest reliability (intraclass correlation coefficient=0.89). Its internal consistency was 0.71, and its convergent validity was confirmed by good correlation coefficient between the OMPQ and PDQ total scores ( r =0.72, p <0.05). No ceiling or floor effects were observed. The Persian version of the OMPQ is acceptable for the target society in terms of face validity, construct validity, reliability, and consistency. It is therefore considered a useful instrument for screening Iranian patients with LBP.
Significant Differences Characterise the Correlation Coefficients between Biocide and Antibiotic Susceptibility Profiles in Staphylococcus aureus.

PubMed

Oggioni, Marco R; Coelho, Joana Rosado; Furi, Leonardo; Knight, Daniel R; Viti, Carlo; Orefici, Graziella; Martinez, Jose-Luis; Freitas, Ana Teresa; Coque, Teresa M; Morrissey, Ian

2015-01-01

There is a growing concern by regulatory authorities for the selection of antibiotic resistance caused by the use of biocidal products. We aimed to complete the detailed information on large surveys by investigating the relationship between biocide and antibiotic susceptibility profiles of a large number of Staphylococcus aureus isolates using four biocides and antibiotics commonly used in clinical practice. The minimal inhibitory concentration (MIC) for most clinically-relevant antibiotics was determined according to the standardized methodology for over 1600 clinical S. aureus isolates and compared to susceptibility profiles of benzalkonium chloride, chlorhexidine, triclosan, and sodium hypochlorite. The relationship between antibiotic and biocide susceptibility profiles was evaluated using non-linear correlations. The main outcome evidenced was an absence of any strong or moderate statistically significant correlation when susceptibilities of either triclosan or sodium hypochlorite were compared for any of the tested antibiotics. On the other hand, correlation coefficients for MICs of benzalkonium chloride and chlorhexidine were calculated above 0.4 for susceptibility to quinolones, beta-lactams, and also macrolides. Our data do not support any selective pressure for association between biocides and antibiotics resistance and furthermore do not allow for a defined risk evaluation for some of the compounds. Importantly, our data clearly indicate that there does not involve any risk of selection for antibiotic resistance for the compounds triclosan and sodium hypochlorite. These data hence infer that biocide selection for antibiotic resistance has had so far a less significant impact than feared.
Validating hospital antibiotic purchasing data as a metric of inpatient antibiotic use

PubMed Central

Tan, Charlie; Ritchie, Michael; Alldred, Jason; Daneman, Nick

2016-01-01

Objectives Antibiotic purchasing data are a widely used, but unsubstantiated, measure of antibiotic consumption. To validate this source, we compared purchasing data from hospitals and external medical databases with patient-level dispensing data. Methods Antibiotic purchasing and dispensing data from internal hospital records and purchasing data from IMS Health were obtained for two hospitals between May 2013 and April 2015. Internal purchasing data were validated against dispensing data, and IMS data were compared with both internal metrics. Scatterplots of individual antimicrobial data points were generated; Pearson's correlation and linear regression coefficients were computed. A secondary analysis re-examined these correlations over shorter calendar periods. Results Internal purchasing data were strongly correlated with dispensing data, with correlation coefficients of 0.90 (95% CI = 0.83–0.95) and 0.98 (95% CI = 0.95–0.99) at hospitals A and B, respectively. Although dispensing data were consistently lower than purchasing data, this was attributed to a single antibiotic at both hospitals. IMS data were favourably correlated with, but underestimated, internal purchasing and dispensing data. This difference was accounted for by eight antibiotics for which direct sales from some manufacturers were not included in the IMS database. The correlation between purchasing and dispensing data was consistent across periods as short as 3 months, but not at monthly intervals. Conclusions Both internal and external antibiotic purchasing data are strongly correlated with dispensing data. If outliers are accounted for appropriately, internal purchasing data could be used for cost-effective evaluation of antimicrobial stewardship programmes, and external data sets could be used for surveillance and research across geographical regions. PMID:26546668
Validation of the King's Sarcoidosis Questionnaire (KSQ) in a Dutch sarcoidosis population.

PubMed

Van Manen, Mirjam J G; Wapenaar, Monique; Strookappe, Bert; Drent, Marjolein; Elfferich, Marjon; de Vries, Jolanda; Gosker, Harry R; Birring, Surinder S; Patel, Amit S; van den Toorn, Leon; van den Blink, Bernt; Boomars, Karin; Hoitsma, Elske; Wijsenbeek, Marlies S

2016-03-29

The King's Sarcoidosis Questionnaire (KSQ) is a brief questionnaire assessing health status using five modules (General Health Status, Lung, Eyes, Skin, Medication) in patients with sarcoidosis. The KSQ was only validated in one English sarcoidosis cohort. The aim of this study was to validate the KSQ in a Dutch sarcoidosis population. The KSQ was translated according to international guidelines and tested in interviews with patients. Consecutive outpatients completed multiple questionnaires twice, two weeks apart. Construct validity, internal consistency and repeatability were determined. Of the 98 patients included 85 had lung, 22 skin and 24 eye disease. There was good construct validity of the KSQ General Health Status module against the World Health Organization Quality of Life-BREF questionnaire. The Medication module correlated weak to moderate with most questionnaires. The correlations with organ-specific questionnaires varied from strong for Eyes (r=0.75), Skin (r=-0.62) to moderate for Lung (r=-0.45 with MRC breathlessness scale). Internal consistency was good for all KSQ modules (Cronbach's α 0.72-0.93). Intraclass correlation coefficients (0.70-0.90) and Bland-Altman plots showed good repeatability of the KSQ. The Dutch KSQ is the first translation of the English KSQ, validated in a Dutch sarcoidosis population.
Adults' past-day recall of sedentary time: reliability, validity, and responsiveness.

PubMed

Clark, Bronwyn K; Winkler, Elisabeth; Healy, Genevieve N; Gardiner, Paul G; Dunstan, David W; Owen, Neville; Reeves, Marina M

2013-06-01

Past-day recall rather than recall of past week or a usual/typical day may improve the validity of self-reported sedentary time measures. This study examined the test-retest reliability, criterion validity, and responsiveness of the seven-item questionnaire, Past-day Adults' Sedentary Time (PAST). Participants (breast cancer survivors, n = 90, age = 33-75 yr, body mass index = 25-40 kg·m) in a 6-month randomized controlled trial of a lifestyle-based weight loss intervention completed the interviewer-administered PAST questionnaire about time spent sitting/lying on the previous day for work, transport, television viewing, nonwork computer use, reading, hobbies, and other purposes (summed for total sedentary time). The instrument was administered at baseline, 7 d later for test-retest reliability (n = 86), and at follow-up. ActivPAL3-assessed sit/lie time in bouts of ≥5 min during waking hours on the recall day was used as the validity criterion measure at both baseline (n = 72) and follow-up (n = 68). Analyses included intraclass correlation coefficients, Pearson's correlations (r), and Bland-Altman plots and responsiveness index. The PAST had fair to good test-retest reliability (intraclass correlation coefficient = 0.50, 95% confidence interval [CI] = 0.32-0.64). At baseline, the correlation between PAST and activPAL sit/lie time was r = 0.57 (95% CI = 0.39-0.71). The mean difference between PAST at baseline and retest was -25 min (5.2%), 95% limits of agreement = -5.9 to 5.0 h, and the activPAL sit/lie time was -9 min (1.8%), 95% limits of agreement = -4.9 to 4.6 h. The PAST showed small but significant responsiveness (-0.44, 95% CI = -0.92 to -0.04); responsiveness of activPAL sit/lie time was not significant. The PAST questionnaire provided an easy-to-administer measure of sedentary time in this sample. Validity and reliability findings compare favorably with other sedentary time questionnaires. Past-day recall of sedentary time shows promise for use in
Validating automated kidney stone volumetry in computed tomography and mathematical correlation with estimated stone volume based on diameter.

PubMed

Wilhelm, Konrad; Miernik, Arkadiusz; Hein, Simon; Schlager, Daniel; Adams, Fabian; Benndorf, Matthias; Fritz, Benjamin; Langer, Mathias; Hesse, Albrecht; Schoenthaler, Martin; Neubauer, Jakob

2018-06-02

To validate AutoMated UroLithiasis Evaluation Tool (AMULET) software for kidney stone volumetry and compare its performance to standard clinical practice. Maximum diameter and volume of 96 urinary stones were measured as reference standard by three independent urologists. The same stones were positioned in an anthropomorphic phantom and CT scans acquired in standard settings. Three independent radiologists blinded to the reference values took manual measurements of the maximum diameter and automatic measurements of maximum diameter and volume. An "expected volume" was calculated based on manual diameter measurements using the formula: V=4/3 πr³. 96 stones were analyzed in the study. We had initially aimed to assess 100. Nine were replaced during data acquisition due of crumbling and 4 had to be excluded because the automated measurement did not work. Mean reference maximum diameter was 13.3 mm (5.2-32.1 mm). Correlation coefficients among all measured outcomes were compared. The correlation between the manual and automatic diameter measurements to the reference was 0.98 and 0.91, respectively (p<0.001). Mean reference volume was 1200 mm³ (10-9000 mm³). The correlation between the "expected volume" and automatically measured volume to the reference was 0.95 and 0.99, respectively (p<0.001). Patients' kidney stone burden is usually assessed according to maximum diameter. However, as most stones are not spherical, this entails a potential bias. Automated stone volumetry is possible and significantly more accurate than diameter-based volumetric calculations. To avoid bias in clinical trials, size should be measured as volume. However, automated diameter measurements are not as accurate as manual measurements.
Penalized spline estimation for functional coefficient regression models.

PubMed

Cao, Yanrong; Lin, Haiqun; Wu, Tracy Z; Yu, Yan

2010-04-01

The functional coefficient regression models assume that the regression coefficients vary with some "threshold" variable, providing appreciable flexibility in capturing the underlying dynamics in data and avoiding the so-called "curse of dimensionality" in multivariate nonparametric estimation. We first investigate the estimation, inference, and forecasting for the functional coefficient regression models with dependent observations via penalized splines. The P-spline approach, as a direct ridge regression shrinkage type global smoothing method, is computationally efficient and stable. With established fixed-knot asymptotics, inference is readily available. Exact inference can be obtained for fixed smoothing parameter λ, which is most appealing for finite samples. Our penalized spline approach gives an explicit model expression, which also enables multi-step-ahead forecasting via simulations. Furthermore, we examine different methods of choosing the important smoothing parameter λ: modified multi-fold cross-validation (MCV), generalized cross-validation (GCV), and an extension of empirical bias bandwidth selection (EBBS) to P-splines. In addition, we implement smoothing parameter selection using mixed model framework through restricted maximum likelihood (REML) for P-spline functional coefficient regression models with independent observations. The P-spline approach also easily allows different smoothness for different functional coefficients, which is enabled by assigning different penalty λ accordingly. We demonstrate the proposed approach by both simulation examples and a real data application.
An agreement coefficient for image comparison

USGS Publications Warehouse

Ji, Lei; Gallo, Kevin

2006-01-01

Combination of datasets acquired from different sensor systems is necessary to construct a long time-series dataset for remotely sensed land-surface variables. Assessment of the agreement of the data derived from various sources is an important issue in understanding the data continuity through the time-series. Some traditional measures, including correlation coefficient, coefficient of determination, mean absolute error, and root mean square error, are not always optimal for evaluating the data agreement. For this reason, we developed a new agreement coefficient for comparing two different images. The agreement coefficient has the following properties: non-dimensional, bounded, symmetric, and distinguishable between systematic and unsystematic differences. The paper provides examples of agreement analyses for hypothetical data and actual remotely sensed data. The results demonstrate that the agreement coefficient does include the above properties, and therefore is a useful tool for image comparison.
Drag Coefficient Estimation in Orbit Determination

NASA Astrophysics Data System (ADS)

McLaughlin, Craig A.; Manee, Steve; Lichtenberg, Travis

2011-07-01

Drag modeling is the greatest uncertainty in the dynamics of low Earth satellite orbits where ballistic coefficient and density errors dominate drag errors. This paper examines fitted drag coefficients found as part of a precision orbit determination process for Stella, Starlette, and the GEOSAT Follow-On satellites from 2000 to 2005. The drag coefficients for the spherical Stella and Starlette satellites are assumed to be highly correlated with density model error. The results using MSIS-86, NRLMSISE-00, and NRLMSISE-00 with dynamic calibration of the atmosphere (DCA) density corrections are compared. The DCA corrections were formulated for altitudes of 200-600 km and are found to be inappropriate when applied at 800 km. The yearly mean fitted drag coefficients are calculated for each satellite for each year studied. The yearly mean drag coefficients are higher for Starlette than Stella, where Starlette is at a higher altitude. The yearly mean fitted drag coefficients for all three satellites decrease as solar activity decreases after solar maximum.

Validity and reliability of the Hawaii anaerobic run test.

PubMed

Kimura, Iris F; Stickley, Christopher D; Lentz, Melissa A; Wages, Jennifer J; Yanagi, Kazuhiko; Hetzler, Ronald K

2014-05-01

This study examined the reliability and validity of the Hawaii anaerobic run test (HART) by comparing anaerobic capacity measures obtained to those during the Wingate Anaerobic Test (WAnT). Ninety-six healthy physically active volunteers (age, 22.0 ± 2.8 years; height, 163.9 ± 9.5 cm; body mass, 70.6 ± 14.7 kg; body fat %, 19.29 ± 5.39%) participated in this study. Each participant performed 2 anaerobic capacity tests: the WAnT and the HART by random assignment on separate days. The reliability of the HART was calculated from 2 separate trials of the test and then determined through intraclass correlation coefficients (ICCs). Blood samples were collected, and lactate was analyzed both pretest and posttest for each of the 2 exercise modes. Heart rate and rate of perceived exertion were also measured pre- and post-exercise. Hawaii anaerobic run test peak and mean momentum were calculated as body mass times highest or average split velocity, respectively. Intraclass correlation coefficients between trials of the HART for peak and mean momentum were 0.98 and 0.99, respectively (SEM = 18.8 and 25.7, respectively). Validity of the HART was established through comparison of momentum on the HART with power on the WAnT. High correlations were found between peak power and peak momentum (r = 0.88), as well as mean power and mean momentum (r = 0.94). The HART was considered to be a reliable test of anaerobic power. The HART was also determined to be a valid test of anaerobic power when compared with the WAnT. When testing healthy college-aged individuals, the HART offers an easy and inexpensive alternative maximal effort anaerobic power test to other established tests.
Reliability and Validity of the Musculoskeletal Tumor Society Scoring System for the Upper Extremity in Japanese Patients.

PubMed

Uehara, Kosuke; Ogura, Koichi; Akiyama, Toru; Shinoda, Yusuke; Iwata, Shintaro; Kobayashi, Eisuke; Tanzawa, Yoshikazu; Yonemoto, Tsukasa; Kawano, Hirotaka; Kawai, Akira

2017-09-01

The Musculoskeletal Tumor Society (MSTS) scoring system developed in 1993 is a widely used disease-specific evaluation tool for assessment of physical function in patients with musculoskeletal tumors; however, only a few studies have confirmed its reliability and validity. The aim of this study was to validate the MSTS scoring system for the upper extremity (MSTS-UE) in Japanese patients with musculoskeletal tumors for use by others in research. Does the MSTS-UE have: (1) sufficient reliability and internal consistency; (2) adequate construct validity; and (3) reasonable criterion validity in comparison to the Toronto Extremity Salvage Score (TESS) or SF-36? Reliability was performed using test-retest analysis, and internal consistency was evaluated with Cronbach's alpha coefficient. Construct validity was evaluated using a scree plot to confirm the construct number and the Akaike information criterion network. Criterion validity was evaluated by comparing the MSTS-UE with the TESS and SF-36. The test-retest reliability with intraclass correlation coefficient (0.95; 95% CI, 0.91-0.97) was excellent, and internal consistency with Cronbach's α (0.7; 95% CI, 0.53-0.81) was acceptable. There were no ceiling and floor effects. The Akaike Information Criterion network showed that lifting ability, pain, and dexterity played central roles among the components. The MSTS-UE showed substantial correlation with the TESS scoring scale (r = 0.75; p < 0.001) and fair correlation with the SF-36 physical component summary (r = 0.37; p = 0.007). Although the MSTS-UE showed slight correlation with the SF-36 mental component summary, the emotional acceptance component of the MSTS-UE showed fair correlation (r = 0.29; p = 0.039). We can conclude that the MSTS is not an adequate measure of general health-related quality of life; however, this system was designed mainly to be a simple measure of function in a single extremity. To evaluate the mental state of patients with
Investigating bias in squared regression structure coefficients

PubMed Central

Nimon, Kim F.; Zientek, Linda R.; Thompson, Bruce

2015-01-01

The importance of structure coefficients and analogs of regression weights for analysis within the general linear model (GLM) has been well-documented. The purpose of this study was to investigate bias in squared structure coefficients in the context of multiple regression and to determine if a formula that had been shown to correct for bias in squared Pearson correlation coefficients and coefficients of determination could be used to correct for bias in squared regression structure coefficients. Using data from a Monte Carlo simulation, this study found that squared regression structure coefficients corrected with Pratt's formula produced less biased estimates and might be more accurate and stable estimates of population squared regression structure coefficients than estimates with no such corrections. While our findings are in line with prior literature that identified multicollinearity as a predictor of bias in squared regression structure coefficients but not coefficients of determination, the findings from this study are unique in that the level of predictive power, number of predictors, and sample size were also observed to contribute bias in squared regression structure coefficients. PMID:26217273
Reliability and validity of television food advertising questionnaire in Malaysia.

PubMed

Zalma, Abdul Razak; Safiah, Md Yusof; Ajau, Danis; Khairil Anuar, Md Isa

2015-09-01

Interventions to counter the influence of television food advertising amongst children are important. Thus, reliable and valid instrument to assess its effect is needed. The objective of this study was to determine the reliability and validity of such a questionnaire. The questionnaire was administered twice on 32 primary schoolchildren aged 10-11 years in Selangor, Malaysia. The interval between the first and second administration was 2 weeks. Test-retest method was used to examine the reliability of the questionnaire. Intra-rater reliability was determined by kappa coefficient and internal consistency by Cronbach's alpha coefficient. Construct validity was evaluated using factor analysis. The test-retest correlation showed moderate-to-high reliability for all scores (r = 0.40*, p = 0.02 to r = 0.95**, p = 0.00), with one exception, consumption of fast foods (r = 0.24, p = 0.20). Kappa coefficient showed acceptable-to-strong intra-rater reliability (K = 0.40-0.92), except for two items under knowledge on television food advertising (K = 0.26 and K = 0.21) and one item under preference for healthier foods (K = 0.33). Cronbach's alpha coefficient indicated acceptable internal consistency for all scores (0.45-0.60). After deleting two items under Consumption of Commonly Advertised Food, the items showed moderate-to-high loading (0.52, 0.84, 0.42 and 0.42) with the Scree plot showing that there was only one factor. The Kaiser-Meyer-Olkin was 0.60, showing that the sample was adequate for factor analysis. The questionnaire on television food advertising is reliable and valid to assess the effect of media literacy education on television food advertising on schoolchildren. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Cross-cultural adaptation and validation of the Persian version of the Intermittent and Constant Osteoarthritis Pain Measure for the knee.

PubMed

Panah, Sara Hojat; Baharlouie, Hamze; Rezaeian, Zahra Sadat; Hawker, Gilian

2016-01-01

The present study aimed to translate and evaluate the reliability and validity of the Persian version of the 11-item Intermittent and Constant Osteoarthritis Pain (ICOAP) measure in Iranian subjects with Knee Osteoarthritis (KOA). The ICOAP questionnaire was translated according to the Manufacturers Alliance for Productivity and Innovation (MAPI) protocol. The procedure consisted of forward and backward translation, as well as the assessment of the psychometric properties of the Persian version of the questionnaire. A sample of 230 subjects with KOA was asked to complete the Persian versions of ICOAP and Knee injury and Osteoarthritis Outcome Score (KOOS). The ICOAP was readministered to forty subjects five days after the first visit. Test-retest reliability was assessed using Intraclass Correlation Coefficient (ICC), and internal consistency was assessed by Cronbach's alpha and item-total correlation. The correlation between ICOAP and KOOS was determined using Spearman's correlation coefficient. Subjects found the Persian-version of the ICOAP to be clear, simple, and unambiguous, confirming its face validity. Spearman correlations between ICOAP total and subscale scores with KOOS scores were between 0.5 and 0.7, confirming construct validity. Cronbach's alpha, used to assess internal consistency, was 0.89, 0.93, and 0.92 for constant pain, intermittent pain, and total pain scores, respectively. The ICC was 0.90 for constant pain and 0.91 for the intermittent pain and total pain score. The Persian version of the ICOAP is a reliable and valid outcome measure that can be used in Iranian subjects with KOA.
Validation of a German Version of the Ethical Leadership at Work Questionnaire by Kalshoven et al. (2011)

PubMed Central

Steinmann, Barbara; Nübold, Annika; Maier, Günter W.

2016-01-01

The present study evaluates the psychometric properties of a German version of the Ethical Leadership at Work questionnaire (ELW-D), and further embeds the construct of ethical leadership within its nomological network. Confirmatory factor analyses (CFAs) based on the total sample of N = 363 employees support the assumed seven-factor structure of the German translation. Within a sub-sample of N = 133, the ELW-D shows positive correlations with related leadership behaviors (transformational leadership, contingent reward, and servant leadership), and negative correlations with destructive ones (passive leadership, autocratic leadership, and abusive supervision), approving convergent validity of the scale. Comparisons of correlated correlation coefficients reveal restrictions of its discriminant validity. In support of the criterion-related validity (N = 100), the ELW-D relates to work-related attitudes (e.g., job satisfaction, satisfaction with the leader, trust in the leader) and follower behaviors (e.g., extra effort, organizational citizenship behavior) in the way expected. Besides, ELW-D-dimensions show incremental validity over and above the Ethical Leadership Scale, emphasizing the added value of this questionnaire. PMID:27065916
Validation of a German Version of the Ethical Leadership at Work Questionnaire by Kalshoven et al. (2011).

PubMed

Steinmann, Barbara; Nübold, Annika; Maier, Günter W

2016-01-01

The present study evaluates the psychometric properties of a German version of the Ethical Leadership at Work questionnaire (ELW-D), and further embeds the construct of ethical leadership within its nomological network. Confirmatory factor analyses (CFAs) based on the total sample of N = 363 employees support the assumed seven-factor structure of the German translation. Within a sub-sample of N = 133, the ELW-D shows positive correlations with related leadership behaviors (transformational leadership, contingent reward, and servant leadership), and negative correlations with destructive ones (passive leadership, autocratic leadership, and abusive supervision), approving convergent validity of the scale. Comparisons of correlated correlation coefficients reveal restrictions of its discriminant validity. In support of the criterion-related validity (N = 100), the ELW-D relates to work-related attitudes (e.g., job satisfaction, satisfaction with the leader, trust in the leader) and follower behaviors (e.g., extra effort, organizational citizenship behavior) in the way expected. Besides, ELW-D-dimensions show incremental validity over and above the Ethical Leadership Scale, emphasizing the added value of this questionnaire.
Reliability and Validation of the International Consultation on Incontinence Questionnaire in Over Active Bladder to Persian Language.

PubMed

Sari Motlagh, Reza; Hajebrahimi, Sakineh; Sadeghi-Bazargani, Homayoun; Joodi Tutunsaz, Javad

2015-05-01

Overactive bladder syndrome is a common syndrome in the world in both men and women. Correct diagnosis and accurate measurement of symptoms severity and also quality of life of patients is necessary to ensure proper treatment and to facilitate sound relationships among patients, researchers and doctors. The International Consultation on Incontinence Questionnaire in Over Active Bladder (ICIQ-OAB) questionnaire is a concise and strong tool to evaluate the symptoms of OAB and their effects on patients' quality of life and treatment results. The objective of this study was to translate and validate a simple and strong tool that could be used in clinics and research. First, the original British English questionnaire was translated into Persian by two bilingual and originally Persian-speaking translators. Then the Persian version was back translated to English and a native English speaker studied and compared the questionnaire with the original version. At the end, the translated and corrected Persian version was finalized by a research team. Content validity of the items and ensuring that the questions could convey the main concept to readers was assessed through Modified Content Validity Index (MCVI). Reliability was calculated by Cronbach's α coefficient. Internal Consistency of the questionnaire with the calculation of Kendall correlation coefficient were evaluated by performing test-retest in 50 participants. The modified content validity index was > 0.78 for all of the questions. Cronbach's α coefficient was calculated 0.76 for all of the participants. Kendall correlation coefficient was calculated for test-re-test assessment 0.66. Both of which indicates the reliability of this questionnaire. Persian version of ICIQ-OAB questionnaire is a simple and strong tool for research, treatment and screening purposes. © 2014 Wiley Publishing Asia Pty Ltd.
Identifying Careless Responding With the Psychopathic Personality Inventory-Revised Validity Scales.

PubMed

Marcus, David K; Church, Abere Sawaqdeh; O'Connell, Debra; Lilienfeld, Scott O

2018-01-01

The Psychopathic Personality Inventory-Revised (PPI-R) includes validity scales that assess Deviant Responding (DR), Virtuous Responding, and Inconsistent Responding. We examined the utility of these scales for identifying careless responding using data from two online studies that examined correlates of psychopathy in college students (Sample 1: N = 583; Sample 2: N = 454). Compared with those below the cut scores, those above the cut on the DR scale yielded consistently lower validity coefficients when PPI-R scores were correlated with corresponding scales from the Triarchic Psychopathy Measure. The other three PPI-R validity scales yielded weaker and less consistent results. Participants who completed the studies in an inordinately brief amount of time scored significantly higher on the DR and Virtuous Responding scales than other participants. Based on the findings from the current studies, researchers collecting PPI-R data online should consider identifying and perhaps screening out respondents with elevated scores on the DR scale.
Reliability and construct validity of the Spanish version of the 6-item CTS symptoms scale for outcomes assessment in carpal tunnel syndrome.

PubMed

Rosales, Roberto S; Martin-Hidalgo, Yolanda; Reboso-Morales, Luis; Atroshi, Isam

2016-03-03

The purpose of this study was to assess the reliability and construct validity of the Spanish version of the 6-item carpal tunnel syndrome (CTS) symptoms scale (CTS-6). In this cross-sectional study 40 patients diagnosed with CTS based on clinical and neurophysiologic criteria, completed the standard Spanish versions of the CTS-6 and the disabilities of the arm, shoulder and hand (QuickDASH) scales on two occasions with a 1-week interval. Internal-consistency reliability was assessed with the Cronbach alpha coefficient and test-retest reliability with the intraclass correlation coefficient, two way random effect model and absolute agreement definition (ICC2,1). Cross-sectional precision was analyzed with the Standard Error of the Measurement (SEM). Longitudinal precision for test-retest reliability coefficient was assessed with the Standard Error of the Measurement difference (SEMdiff) and the Minimal Detectable Change at 95 % confidence level (MDC95). For assessing construct validity it was hypothesized that the CTS-6 would have a strong positive correlation with the QuickDASH, analyzed with the Pearson correlation coefficient (r). The standard Spanish version of the CTS-6 presented a Cronbach alpha of 0.81 with a SEM of 0.3. Test-retest reliability showed an ICC of 0.85 with a SRMdiff of 0.36 and a MDC95 of 0.7. The correlation between CTS-6 and the QuickDASH was concordant with the a priori formulated construct hypothesis (r 0.69) CONCLUSIONS: The standard Spanish version of the 6-item CTS symptoms scale showed good internal consistency, test-retest reliability and construct validity for outcomes assessment in CTS. The CTS-6 will be useful to clinicians and researchers in Spanish speaking parts of the world. The use of standardized outcome measures across countries also will facilitate comparison of research results in carpal tunnel syndrome.
Validation of EORTC IN-PATSAT32 for Chinese cancer patients.

PubMed

Zhang, Lei; Dai, Zhenbo; Cheng, Siying; Xie, Shumin; Woo, Stephanie Mu-Lian; Luo, Zhiqin; Wu, Jinglian; Gao, Tianwen; Liu, Jiahao; Zhang, Kai; Zhang, Jing; Jia, Xinyu; Miller, Adam R; Wang, Changli

2015-09-01

The aim of this study is to test the psychometric properties and acceptability of the European Organization for Research and Treatment of Cancer (EORTC) inpatient satisfaction with care questionnaire 32 (IN-PATSAT32) for evaluating Chinese cancer patients and to analyze the influence of age, educational level, diagnostic time, and tumor stage on patient satisfaction. Three hundred two cancer inpatients in Tianjin Cancer Institution and Hospital from June 2013 to December 2013 were recruited for this study. All participants self-administered the EORTC IN-PATSAT32 and EORTC quality of life questionnaire-core 30 (QLQ-C30). Psychometric evaluation of the validity, reliability, acceptability, as well as the influence of age, educational level, diagnostic time, and tumor stage on patient satisfaction, was conducted. A favorable internal consistency reliability was confirmed, as the Cronbach's α coefficients were >0.80 for all scales in the EORTC IN-PATSAT32, ranging from 0.849 to 0.944. Multi-trait scaling analysis showed that all item-scale correlation coefficients met the standard of convergent validity, and 79.3 % met the standard of discriminant validity. Weak correlations were found between the scales and single items of the EORTC IN-PATSAT32 and EORTC QLQ-C30, proving the validity of EORTC IN-PATSAT32. None of the EORTC IN-PATSAT32 scales were able to discriminate between patients across age categories, while significant influences of educational level on doctors' and nurses' conduct, as well as influences of diagnostic time and tumor stage on nurses' conduct, and information provision scales were discovered. The questionnaire was easily understood with a satisfactory acceptability. The EORTC IN-PATSAT32 appears to be a reliable, valid, and acceptable instrument to use on cancer patients and is appropriate for measuring the patient satisfaction of Chinese patients.
Environmental education curriculum evaluation questionnaire: A reliability and validity study

NASA Astrophysics Data System (ADS)

Minner, Daphne Diane

The intention of this research project was to bridge the gap between social science research and application to the environmental domain through the development of a theoretically derived instrument designed to give educators a template by which to evaluate environmental education curricula. The theoretical base for instrument development was provided by several developmental theories such as Piaget's theory of cognitive development, Developmental Systems Theory, Life-span Perspective, as well as curriculum research within the area of environmental education. This theoretical base fueled the generation of a list of components which were then translated into a questionnaire with specific questions relevant to the environmental education domain. The specific research question for this project is: Can a valid assessment instrument based largely on human development and education theory be developed that reliably discriminates high, moderate, and low quality in environmental education curricula? The types of analyses conducted to answer this question were interrater reliability (percent agreement, Cohen's Kappa coefficient, Pearson's Product-Moment correlation coefficient), test-retest reliability (percent agreement, correlation), and criterion-related validity (correlation). Face validity and content validity were also assessed through thorough reviews. Overall results indicate that 29% of the questions on the questionnaire demonstrated a high level of interrater reliability and 43% of the questions demonstrated a moderate level of interrater reliability. Seventy-one percent of the questions demonstrated a high test-retest reliability and 5% a moderate level. Fifty-five percent of the questions on the questionnaire were reliable (high or moderate) both across time and raters. Only eight questions (8%) did not show either interrater or test-retest reliability. The global overall rating of high, medium, or low quality was reliable across both coders and time, indicating
Reliability of environmental sampling culture results using the negative binomial intraclass correlation coefficient.

PubMed

Aly, Sharif S; Zhao, Jianyang; Li, Ben; Jiang, Jiming

2014-01-01

The Intraclass Correlation Coefficient (ICC) is commonly used to estimate the similarity between quantitative measures obtained from different sources. Overdispersed data is traditionally transformed so that linear mixed model (LMM) based ICC can be estimated. A common transformation used is the natural logarithm. The reliability of environmental sampling of fecal slurry on freestall pens has been estimated for Mycobacterium avium subsp. paratuberculosis using the natural logarithm transformed culture results. Recently, the negative binomial ICC was defined based on a generalized linear mixed model for negative binomial distributed data. The current study reports on the negative binomial ICC estimate which includes fixed effects using culture results of environmental samples. Simulations using a wide variety of inputs and negative binomial distribution parameters (r; p) showed better performance of the new negative binomial ICC compared to the ICC based on LMM even when negative binomial data was logarithm, and square root transformed. A second comparison that targeted a wider range of ICC values showed that the mean of estimated ICC closely approximated the true ICC.
Blinded versus unblinded estimation of a correlation coefficient to inform interim design adaptations.

PubMed

Kunz, Cornelia U; Stallard, Nigel; Parsons, Nicholas; Todd, Susan; Friede, Tim

2017-03-01

Regulatory authorities require that the sample size of a confirmatory trial is calculated prior to the start of the trial. However, the sample size quite often depends on parameters that might not be known in advance of the study. Misspecification of these parameters can lead to under- or overestimation of the sample size. Both situations are unfavourable as the first one decreases the power and the latter one leads to a waste of resources. Hence, designs have been suggested that allow a re-assessment of the sample size in an ongoing trial. These methods usually focus on estimating the variance. However, for some methods the performance depends not only on the variance but also on the correlation between measurements. We develop and compare different methods for blinded estimation of the correlation coefficient that are less likely to introduce operational bias when the blinding is maintained. Their performance with respect to bias and standard error is compared to the unblinded estimator. We simulated two different settings: one assuming that all group means are the same and one assuming that different groups have different means. Simulation results show that the naïve (one-sample) estimator is only slightly biased and has a standard error comparable to that of the unblinded estimator. However, if the group means differ, other estimators have better performance depending on the sample size per group and the number of groups. © 2016 The Authors. Biometrical Journal Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Validation and reliability of the Physical Activity Scale for the Elderly in Chinese population.

PubMed

Ngai, Shirley P C; Cheung, Roy T H; Lam, Priscillia L; Chiu, Joseph K W; Fung, Eric Y H

2012-05-01

Physical Activity Scale for the Elderly (PASE) is a widely used questionnaire in epidemiological studies for assessing the physical activity level of elderly. This study aims to translate and validate PASE in Chinese population. Cross-sectional study. Chinese elderly aged 65 or above. The original English version of PASE was translated into Chinese (PASE-C) following standardized translation procedures. Ninety Chinese elderly aged 65 or above were recruited in the community. Test-retest reliability was determined by comparing the scores obtained from two separate administrations by the intraclass correlation coefficient. Validity was evaluated by Spearman's rank correlation coefficients between PASE and Medical Outcome Survey 36-Item Short Form Health Survey (SF-36), grip strength, single-leg-stance, 5 times sit-to-stand and 10-m walk. PASE-C demonstrated good test-retest reliability (intraclass correlation coefficient = 0.81). Fair to moderate association were found between PASE-C and most of the subscales of SF-36 (rs = 0.285 to 0.578, p < 0.01), grip strength (rs = 0.405 to 0.426, p < 0.001), single-leg-stance (rs = 0.470 to 0.548, p < 0.001), 5 times sit-to-stand (rs = -0.33, p = 0.001) and 10-m walk (rs = -0.281, p = 0.007). PASE-C is a reliable and valid instrument for assessing the physical activity level of elderly in Chinese population.
[Translation and validation in italian of the Moral Distress Scale for psychiatric nurses (MDS-P)].

PubMed

Canciani, Eleonora; Spotti, Daniela; Bonetti, Loris

2016-01-01

Moral distress (MD) is a painful feeling and/or psychological disequilibrium, which may lead to negative consequences into the wellness of a nurse's working life. Nurses who work in psychiatry are more likely to experience a different type of MD compared with nurses of other contexts. In Italy a tool to evaluate MD in nurses who work in psychiatry doesn't exist. The aim of this study is to validate the Moral Distress Scale for Psychiatric Nurses (MDS-P) in Italian language. For translation the forward and back-translation has been used; the effectiveness regarding content and face validity of the translated scale has been analyzed through a focus group with experts of the field. In order to check the reliability of the scale the test-retest method has been used, by means of the determination of Spearman's correlation coefficient, Intraclass Correlation Coefficient (ICC) and Cronbach's alpha. The forward and back-translation process was successful. During the focus group analysis, 8 items were added to the 15 items of the original scale, due to experts suggestions. 32 nurses took part in the test-retest phase. Spearman's correlation coefficient resulted to be 0,91, ICC > 0,9, Cronbach's alpha calculated on test and retest, was always >0,9. The Italian version of the MDS-P proves to be an effective, appropriate and reliable instrument to measure the MD phenomenon within the population of nurses who work in the psychia- tric field in Italy.
Comparison of RNFL thickness and RPE-normalized RNFL attenuation coefficient for glaucoma diagnosis

NASA Astrophysics Data System (ADS)

Vermeer, K. A.; van der Schoot, J.; Lemij, H. G.; de Boer, J. F.

2013-03-01

Recently, a method to determine the retinal nerve fiber layer (RNFL) attenuation coefficient, based on normalization on the retinal pigment epithelium, was introduced. In contrast to conventional RNFL thickness measures, this novel measure represents a scattering property of the RNFL tissue. In this paper, we compare the RNFL thickness and the RNFL attenuation coefficient on 10 normal and 8 glaucomatous eyes by analyzing the correlation coefficient and the receiver operator curves (ROCs). The thickness and attenuation coefficient showed moderate correlation (r=0.82). Smaller correlation coefficients were found within normal (r=0.55) and glaucomatous (r=0.48) eyes. The full separation between normal and glaucomatous eyes based on the RNFL attenuation coefficient yielded an area under the ROC (AROC) of 1.0. The AROC for the RNFL thickness was 0.9875. No statistically significant difference between the two measures was found by comparing the AROC. RNFL attenuation coefficients may thus replace current RNFL thickness measurements or be combined with it to improve glaucoma diagnosis.
Molecular dynamics calculation of rotational diffusion coefficient of a carbon nanotube in fluid.

PubMed

Cao, Bing-Yang; Dong, Ruo-Yu

2014-01-21

Rotational diffusion processes are correlated with nanoparticle visualization and manipulation techniques, widely used in nanocomposites, nanofluids, bioscience, and so on. However, a systematical methodology of deriving this diffusivity is still lacking. In the current work, three molecular dynamics (MD) schemes, including equilibrium (Green-Kubo formula and Einstein relation) and nonequilibrium (Einstein-Smoluchowski relation) methods, are developed to calculate the rotational diffusion coefficient, taking a single rigid carbon nanotube in fluid argon as a case. We can conclude that the three methods produce same results on the basis of plenty of data with variation of the calculation parameters (tube length, diameter, fluid temperature, density, and viscosity), indicative of the validity and accuracy of the MD simulations. However, these results have a non-negligible deviation from the theoretical predictions of Tirado et al. [J. Chem. Phys. 81, 2047 (1984)], which may come from several unrevealed factors of the theory. The three MD methods proposed in this paper can also be applied to other situations of calculating rotational diffusion coefficient.
Braden scale (ALB) for assessing pressure ulcer risk in hospital patients: A validity and reliability study.

PubMed

Chen, Hong-Lin; Cao, Ying-Juan; Zhang, Wei; Wang, Jing; Huai, Bao-Sha

2017-02-01

The inter-rater reliability of Braden Scale is not so good. We modified the Braden(ALB) scale by defining nutrition subscale based on serum albumin, then assessed it's the validity and reliability in hospital patients. We designed a retrospective study for validity analysis, and a prospective study for reliability analysis. Receiver operating curve (ROC) and area under the curve (AUC) were used to evaluate the predictive validity. Intra-class correlation coefficient (ICC) was used to investigate the inter-rater reliability. Two thousand five hundred twenty-five patients were included for validity analysis, 76 patients (3.0%) developed pressure ulcer. Positive correlation was found between serum albumin and nutrition score in Braden scale (Spearman's coefficient 0.2203, P<0.0001). The AUCs for Braden scale and Braden(ALB) scale predicting pressure ulcer risk were 0.813 (95% CI 0.797-0.828; P<0.0001), and 0.859 (95% CI 0.845-0.872; P<0.0001), respectively. The Braden(ALB) scale was even more valid than the Braden scale (z=1.860, P=0.0628). In different age subgroups, the Braden(ALB) scale seems also more valid than the original Braden scale, but no statistically significant differences were found (P>0.05). The inter-rater reliability study showed the ICC-value for nutrition increased 45.9%, and increased 4.3% for total score. The Braden(ALB) scale has similar validity compared with the original Braden scale for in hospital patients. However, the inter-rater reliability was significantly increased. Copyright © 2016 Elsevier Inc. All rights reserved.
Validation of the Spanish version of the "Questionnaire on the treatment of approximal and occlusal caries".

PubMed

Ruiz, Begoña; Urzúa, Iván; Cabello, Rodrigo; Rodríguez, Gonzalo; Espelid, Ivar

2013-01-01

To translate and validate a Spanish version of the "Questionnaire on the treatment of approximal and occlusal caries" as a method of collecting information about treatment decisions on caries management in Chilean primary health care services. The original questionnaire proposed by Espelid et al. was translated into Spanish using the forward-backward translation technique. Subsequently, validation of the Spanish version was undertaken. Data were collected from two separate samples; first, from 132 Spanish-speaking dentists recruited from primary health care services and second, from 21 individuals characterised as cariologists. Internal consistency was evaluated by the generation of Cronbach's alpha, test-retest reliability was evaluated by Cohen's kappa, convergent validity was evaluated by comparing the total scale scores to a global evaluation of treatment trends and discriminant validity was evaluated by investigating the differences in total scale scores between the Spanish-speaking dentist and cariologist samples. Cronbach's alpha indicated an internal consistency of 0.63 for the entire scale. Cohen's kappa correlation coefficient expressed a test-retest reliability of 0.83. Convergent validity determined a Pearson's correlation coefficient of 0.24 (p < 0.01). The comparison of proportions (chi-squared) indicated that discriminant validity was statistically significant (p < 0.01), using a one-tailed test. The Spanish version of the "Questionnaire on the treatment of approximal and occlusal caries" is a valid and reliable instrument for collecting information regarding treatment decisions in cariology. The clinical relevance of this study is to acquire a reliable instrument that allows for the determination of treatment decisions in Spanish-speaking dentists.

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