64
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Using Rasch rating scale model to reassess the psychometric properties of the Persian version of the PedsQL TM 4.0 Generic Core Scales in school children

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Background

          Item response theory (IRT) is extensively used to develop adaptive instruments of health-related quality of life (HRQoL). However, each IRT model has its own function to estimate item and category parameters, and hence different results may be found using the same response categories with different IRT models. The present study used the Rasch rating scale model (RSM) to examine and reassess the psychometric properties of the Persian version of the PedsQL TM 4.0 Generic Core Scales.

          Methods

          The PedsQL TM 4.0 Generic Core Scales was completed by 938 Iranian school children and their parents. Convergent, discriminant and construct validity of the instrument were assessed by classical test theory (CTT). The RSM was applied to investigate person and item reliability, item statistics and ordering of response categories.

          Results

          The CTT method showed that the scaling success rate for convergent and discriminant validity were 100% in all domains with the exception of physical health in the child self-report. Moreover, confirmatory factor analysis supported a four-factor model similar to its original version. The RSM showed that 22 out of 23 items had acceptable infit and outfit statistics (<1.4, >0.6), person reliabilities were low, item reliabilities were high, and item difficulty ranged from -1.01 to 0.71 and -0.68 to 0.43 for child self-report and parent proxy-report, respectively. Also the RSM showed that successive response categories for all items were not located in the expected order.

          Conclusions

          This study revealed that, in all domains, the five response categories did not perform adequately. It is not known whether this problem is a function of the meaning of the response choices in the Persian language or an artifact of a mostly healthy population that did not use the full range of the response categories. The response categories should be evaluated in further validation studies, especially in large samples of chronically ill patients.

          Related collections

          Most cited references40

          • Record: found
          • Abstract: found
          • Article: not found

          Applying item response theory (IRT) modeling to questionnaire development, evaluation, and refinement.

          Health outcomes researchers are increasingly applying Item Response Theory (IRT) methods to questionnaire development, evaluation, and refinement efforts. To provide a brief overview of IRT, to review some of the critical issues associated with IRT applications, and to demonstrate the basic features of IRT with an example. Example data come from 6,504 adolescent respondents in the National Longitudinal Study of Adolescent Health public use data set who completed to the 19-item Feelings Scale for depression. The sample was split into a development and validation sample. Scale items were calibrated in the development sample with the Graded Response Model and the results were used to construct a 10-item short form. The short form was evaluated in the validation sample by examining the correspondence between IRT scores from the short form and the original, and by comparing the proportion of respondents identified as depressed according to the original and short form observed cut scores. The 19 items varied in their discrimination (slope parameter range: .86-2.66), and item location parameters reflected a considerable range of depression (-.72-3.39). However, the item set is most discriminating at higher levels of depression. In the validation sample IRT scores generated from the short and long forms were correlated at .96 and the average difference in these scores was -.01. In addition, nearly 90% of the sample was classified identically as at risk or not at risk for depression using observed score cut points from the short and long forms. When used appropriately, IRT can be a powerful tool for questionnaire development, evaluation, and refinement, resulting in precise, valid, and relatively brief instruments that minimize response burden.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Optimizing rating scale category effectiveness.

            J. Linacre (2001)
            Rating scales are employed as a means of extracting more information out of an item than would be obtained from a mere "yes/no", "right/wrong" or other dichotomy. But does this additional information increase measurement accuracy and precision? Eight guidelines are suggested to aid the analyst in optimizing the manner in which rating scales categories cooperate in order to improve the utility of the resultant measures. Though these guidelines are presented within the context of Rasch analysis, they reflect aspects of rating scale functioning which impact all methods of analysis. The guidelines feature rating-scale-based data such as category frequency, ordering, rating-to-measure inferential coherence, and the quality of the scale from measurement and statistical perspectives. The manner in which the guidelines prompt recategorization or reconceptualization of the rating scale is indicated. Utilization of the guidelines is illustrated through their application to two published data sets.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              An item response analysis of the pediatric PROMIS anxiety and depressive symptoms scales.

              The Patient-Reported Outcomes Measurement Information System (PROMIS) aims to develop self-reported item banks for clinical research. The PROMIS pediatrics (aged 8-17) project focuses on the development of item banks across several health domains (physical function, pain, fatigue, emotional distress, social role relationships, and asthma symptoms). The psychometric properties of the anxiety and depressive symptom item banks are described. Participants (n = 1,529) were recruited in public school settings, hospital-based outpatient and subspecialty pediatrics clinics. The anxiety (k = 18) and depressive symptoms (k = 21) items were split between two test administration forms. Hierarchical confirmatory factor-analytic models (CFA) were conducted to evaluate scale dimensionality and local dependence. IRT analyses were then used to finalize item banks and short forms. CFA results confirmed that anxiety and depressive symptoms are separate constructs and indicative of negative affect. Items with local dependence and DIF were removed resulting in 15 anxiety and 14 depressive symptoms items. The psychometric differences between short forms and simulated computer adaptive tests are presented. PROMIS pediatric item banks were developed to provide efficient assessment of health-related quality of life domains. This sample provides initial calibrations of anxiety and depressive symptoms item banks and creates PROMIS pediatric instruments, version 1.0.
                Bookmark

                Author and article information

                Journal
                Health Qual Life Outcomes
                Health Qual Life Outcomes
                Health and Quality of Life Outcomes
                BioMed Central
                1477-7525
                2012
                13 March 2012
                : 10
                : 27
                Affiliations
                [1 ]Department of Biostatistics, Shiraz University of Medical Sciences, Shiraz, Iran
                Article
                1477-7525-10-27
                10.1186/1477-7525-10-27
                3353856
                22414135
                a63a844f-6a2d-4758-a136-30237fd30fb0
                Copyright ©2012 Jafari et al; licensee BioMed Central Ltd.

                This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                : 6 December 2011
                : 13 March 2012
                Categories
                Research

                Health & Social care
                rasch model,quality of life,school children,iran
                Health & Social care
                rasch model, quality of life, school children, iran

                Comments

                Comment on this article