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Luis Prieto - One of the best experts on this subject based on the ideXlab platform.

  • Classical Test Theory versus Item Response Theory to Shorten the Inflammatory Bowel Disease Questionnaire (IBDQ)
    The American Journal of Gastroenterology, 2004
    Co-Authors: Luis Prieto, Francesc Casellas, Maria-jose Alcala, J R Armengol, Juan-ramon Malagelada
    Abstract:

    Classical Test Theory versus Item Response Theory to Shorten the Inflammatory Bowel Disease Questionnaire (IBDQ)

  • Classical Test Theory versus rasch analysis for quality of life questionnaire reduction
    Health and Quality of Life Outcomes, 2003
    Co-Authors: Luis Prieto, Jordi Alonso, Rosa Lamarca
    Abstract:

    Background Although health-related quality of life (HRQOL) instruments may offer satisfactory results, their length often limits the extent to which they are actually applied in clinical practice. Efforts to develop short questionnaires have largely focused on reducing existing instruments. The approaches most frequently employed for this purpose rely on statistical procedures that are considered exponents of Classical Test Theory (CTT). Despite the popularity of CTT, two major conceptual limitations have been pointed out: the lack of an explicit ordered continuum of items that represent a unidimensional construct, and the lack of additivity of rating scale data. In contrast to the CTT approach, the Rasch model provides an alternative scaling methodology that enables the examination of the hierarchical structure, unidimensionality and additivity of HRQOL measures. METHODS: In order to empirically compare CTT and Rasch Analysis (RA) results, this paper presents the parallel reduction of a 38-item questionnaire, the Nottingham Health Profile (NHP), through the analysis of the responses of a sample of 9,419 individuals.

Juan-ramon Malagelada - One of the best experts on this subject based on the ideXlab platform.

Patricia Hyland - One of the best experts on this subject based on the ideXlab platform.

  • Generalisability and Classical Test Theory analyses of Koppitz's Scoring System for human figure drawings
    British Journal of Educational Psychology, 2001
    Co-Authors: Gordon Rae, Patricia Hyland
    Abstract:

    Background. Scoring systems to evaluate children's human drawings for intellectual maturity have been found to have good intra- and inter-scorer reliability. However, there is some evidence (McCarthy, 1944) that such scores may not be stable over time. Aim. The aim of the study was to investigate raters and occasions as potential sources of error in children's Draw-a-Person scores using generalisability and Classical Test Theory. Sample. The sample consisted of 85 school children (45 girls and 40 boys) aged between 8 years I month to 9 years and 7 months. Method. The Koppitz Draw-A-Person (1968) Test was administered as a class Test on two occasions with exactly a two-week interval between the occasions. All the children's drawings were scored by the same four raters. Results. Generalisability analyses of the Koppitz scores indicated that the variance components for raters and its interaction with both persons and occasions were very small, suggesting that very little measurement error was associated with the raters. However, the estimated variance component for the interaction of persons by occasions was substantial. With four raters and two occasions the generalisability coefficient was .47. These results were consistent with the Classical Test Theory analysis which indicated generally high inter-rater reliabilities but a low Test-reTest reliability, based on a composite of the four raters. Conclusion. If satisfactory levels of reliability/generalisability are to be achieved with the Koppitz scoring system children have to be Tested on several occasions.

  • Generalisability and Classical Test Theory analyses of Koppitz's scoring system for human figure drawings.
    The British journal of educational psychology, 2001
    Co-Authors: Gordon Rae, Patricia Hyland
    Abstract:

    Scoring systems to evaluate children's human drawings for intellectual maturity have been found to have good intra- and inter-scorer reliability. However, there is some evidence (McCarthy, 1944) that such scores may not be stable over time. The aim of the study was to investigate raters and occasions as potential sources of error in children's Draw-a-Person scores using generalisability and Classical Test Theory. The sample consisted of 85 school children (45 girls and 40 boys) aged between 8 years 1 month to 9 years and 7 months. The Koppitz Draw-A-Person (1968) Test was administered as a class Test on two occasions with exactly a two-week interval between the occasions. All the children's drawings were scored by the same four raters. Generalisability analyses of the Koppitz scores indicated that the variance components for raters and its interaction with both persons and occasions were very small, suggesting that very little measurement error was associated with the raters. However, the estimated variance component for the interaction of persons by occasions was substantial. With four raters and two occasions the generalisability coefficient was .47. These results were consistent with the Classical Test Theory analysis which indicated generally high inter-rater reliabilities but a low Test-reTest reliability, based on a composite of the four raters. If satisfactory levels of reliability/generalisability are to be achieved with the Koppitz scoring system children have to be Tested on several occasions.

Thomas R. Kwapil - One of the best experts on this subject based on the ideXlab platform.

  • Psychometric Properties of the Wisconsin Schizotypy Scales in an Undergraduate Sample: Classical Test Theory, Item Response Theory, and Differential Item Functioning
    Journal of Psychopathology and Behavioral Assessment, 2011
    Co-Authors: Beate P. Winterstein, Terry A. Ackerman, Paul J. Silvia, Thomas R. Kwapil
    Abstract:

    The Wisconsin Schizotypy Scales are widely used for assessing schizotypy in nonclinical and clinical samples. However, they were developed using Classical Test Theory (CTT) and have not had their psychometric properties examined with more sophisticated measurement models. The present study employed item response Theory (IRT) as well as traditional CTT to examine psychometric properties of four of the schizotypy scales on the item and scale level, using a large sample of undergraduate students ( n  = 6,137). In addition, we investigated differential item functioning (DIF) for sex and ethnicity. The analyses revealed many strengths of the four scales, but some items had low discrimination values and many items had high DIF. The results offer useful guidance for applied users and for future development of these scales.

  • psychometric properties of the wisconsin schizotypy scales in an undergraduate sample Classical Test Theory item response Theory and differential item functioning
    Journal of Psychopathology and Behavioral Assessment, 2011
    Co-Authors: Beate P. Winterstein, Terry A. Ackerman, Paul J. Silvia, Thomas R. Kwapil
    Abstract:

    The Wisconsin Schizotypy Scales are widely used for assessing schizotypy in nonclinical and clinical samples. However, they were developed using Classical Test Theory (CTT) and have not had their psychometric properties examined with more sophisticated measurement models. The present study employed item response Theory (IRT) as well as traditional CTT to examine psychometric properties of four of the schizotypy scales on the item and scale level, using a large sample of undergraduate students (n?=?6,137). In addition, we investigated differential item functioning (DIF) for sex and ethnicity. The analyses revealed many strengths of the four scales, but some items had low discrimination values and many items had high DIF. The results offer useful guidance for applied users and for future development of these scales. The items for the Wisconsin Schizotypy Scales are available from Thomas R. Kwapil.

Ron D Hays - One of the best experts on this subject based on the ideXlab platform.

  • overview of Classical Test Theory and item response Theory for the quantitative assessment of items in developing patient reported outcomes measures
    Clinical Therapeutics, 2014
    Co-Authors: Joseph C Cappelleri, Jason J Lundy, Ron D Hays
    Abstract:

    Background: The US Food and Drug Administration’s guidance for industry document on patientreported outcomes (PRO) defines content validity as “the extent to which the instrument measures the concept of interest” (FDA, 2009, p. 12). According to Strauss and Smith (2009), construct validity "is now generally viewed as a unifying form of validity for psychological measurements, subsuming both content and criterion validity” (p. 7). Hence, both qualitative and quantitative information are essential in evaluating the validity of measures. Methods: We review Classical Test Theory and item response Theory (IRT) approaches to evaluating PRO measures, including frequency of responses to each category of the items in a multi-item scale, the distribution of scale scores, floor and ceiling effects, the relationship between item response options and the total score, and the extent to which hypothesized “difficulty” (severity) order of items is represented by observed responses. Results: If a researcher has few qualitative data and wants to get preliminary information about the content validity of the instrument, then descriptive assessments using Classical Test Theory should be the first step. As the sample size grows during subsequent stages of instrument development, confidence in the numerical estimates from Rasch and other IRT models (as well as those of Classical Test Theory) would also grow. Conclusion: Classical Test Theory and IRT can be useful in providing a quantitative assessment of items and scales during the content-validity phase of PROmeasure development. Depending on the particular type of measure and the specific circumstances, the Classical Test Theory and/or the IRT should be considered to help maximize the content validity of PRO measures. (Clin Ther. 2014;36:648–662) & 2014

  • Classical Test Theory and item response Theory analyses of multi-item scales assessing parents' perceptions of their children's dental care.
    Medical care, 2006
    Co-Authors: Ron D Hays, Julie Brown, Lorraine U Brown, Karen L Spritzer, James J Crall
    Abstract:

    Classical Test Theory and item response Theory methods can provide useful and potentially different insights into the performance of items in a survey designed to elicit parental perceptions of dental care delivered to children in publicly funded programs. We sought to illustrate the use of both Classical Test Theory and item response Theory to evaluate survey instruments. : Using 2 years of cross-sectional data collected from enrollees in dental plans in 2001 and 2002, we studied families with children between ages 4 to 18 who were enrolled in 1 of 5 dental plans for 12 months or longer. The 2001 survey yielded a total of 2536 usable surveys and the 2002 survey yielded 2232 useable surveys (50% and 46% response rate, respectively) for a total sample size of 4036 children who used the plan for most or all of their care. The beta version of the CAHPS(R) dental care survey instrument includes 2 global rating items (dental care, dental plan) and multi-item scales assessing getting needed care, getting care quickly, communication with dental providers, office staff, and customer service. Item missing data rates were low. Item-scale correlations for hypothesized scales (corrected for overlap) tended to exceed correlations of items with other scales. Classical Test Theory analyses identified 5 of 10 communication items that did not perform well. Internal consistency reliability estimates for the scales ranged from 0.73 to 0.86. Item response Theory painted a more promising picture than Classical Test Theory for the 2 communication items that assessed access to an interpreter when needed. The beta CAHPS(R) dental survey performed well and the revised instrument is recommended for future studies. Classical Test Theory and item response Theory can provide complementary information about survey items.