SAS macros for longitudinal IRT models

Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Danmark
DOI
10.7287/peerj.preprints.26740v1
Subject Areas
Data Science, Graphics, Programming Languages
Keywords
polytomous IRT model, Birnbaum model, 1PL model, 2PL model, Generalized Partial Credit model, Rasch model, item parameter drift, longitudinal IRT model, SAS, response dependence
Copyright
© 2018 Olsbjerg et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Olsbjerg M, Christensen KB, European Rasch Teaching Group (ERTG). 2018. SAS macros for longitudinal IRT models. PeerJ Preprints 6:e26740v1

Abstract

IRT models are often applied when observed items are used to measure a unidimensional latent variable. Originally used in educational research, IRT models are now widely used when focus is on physical functioning or psychological well-being. Modern applications often need more general models, typically models for multidimensional latent variables or longitudinal models for repeated measurements. This paper describes a collection of SAS macros that can be used for fitting data to, simulating from, and visualizing longitudinal IRT models. The macros encompass dichotomous as well as polytomous item response formats and are sufficiently flexible to accommodate changes in item parameters across time points and local dependence between responses at different time points.

Author Comment

This is a submission to PeerJ Computer Science for review.