The current paper describes new opportunities for patient-centred assessment methods which have come about by the increased adoption of affordable smart technologies in biopsychosocial research and medical care. In this commentary, we review modern assessment methods including item response theory (IRT), computer adaptive testing (CAT), and ecological momentary assessment (EMA) and explain how ...

Mega- or meta-analytic studies (e.g. genome-wide association studies) are increasingly used in behavior genetics. An issue in such studies is that phenotypes are often measured by different instruments across study cohorts, requiring harmonization of measures so that more powerful fixed effect meta-analyses can be employed. Within the Genetics of Personality Consortium, we demonstrate for two c...

BACKGROUND Multi-item questionnaires are important instruments for monitoring health in epidemiological longitudinal studies. Mostly sum-scores are used as a summary measure for these multi-item questionnaires. The objective of this study was to show the negative impact of using sum-score based longitudinal data analysis instead of Item Response Theory (IRT)-based plausible values. METHODS In...

OBJECTIVE To develop a self-reported measure of the subjective impact of pressure ulcers on health-related quality of life (HRQOL) in individuals with spinal cord injury (SCI) as part of the SCI quality of life (SCI-QOL) measurement system. DESIGN Grounded-theory based qualitative item development methods, large-scale item calibration testing, confirmatory factor analysis (CFA), and item resp...

This research examined students’ responses to mathematics problem-solving tasks and applied a general multidimensional IRT model at the response category level. In doing so, cognitive processes were identified and modelled through item response modelling to extract more information than would be provided using conventional practices in scoring items. More specifically, the study consisted of tw...

BACKGROUND Patients-Reported Outcomes (PRO) are increasingly used in clinical and epidemiological research. Two main types of analytical strategies can be found for these data: classical test theory (CTT) based on the observed scores and models coming from Item Response Theory (IRT). However, whether IRT or CTT would be the most appropriate method to analyse PRO data remains unknown. The statis...

This introduction to the R package plink is a (slightly) modified version of Weeks (2010), published in the Journal of Statistical Software. The R package plink has been developed to facilitate the linking of mixed-format tests for multiple groups under a common item design using unidimensional and multidimensional IRT-based methods. This paper presents the capabilities of the package in the co...

of the Dissertation Identifying DIF for Latent Classes with the Dirichlet Process by Miles Satori Chen Doctor of Philosophy in Statistics University of California, Los Angeles, 2015 Professor Peter Bentler, Chair In Item Response Theory (IRT), Differential Item Functioning (DIF) occurs when individuals who have the same ability, but belong to different groups, have different probabilities of an...

The present study applied item response theory (IRT) to the NEO five factor inventory (NEO-FFI) completed by a community based sample of adolescents. The results revealed that many of these personality items may not be discriminating well, with some traits demonstrating greater reliability than others. Furthermore, the threshold values highlighted that the majority of the items had skewed respo...

An approach to essay grading based on signal detection theory (SDT) is presented. SDT offers a basis for understanding rater behavior with respect to the scoring of construct responses, in that it provides a theory of psychological processes underlying the raters’ behavior. The approach also provides measures of the precision of the raters and the accuracy of classifications. An application of ...