Item response theory applications in personality disorder research.

This article describes how item response theory (IRT) has begun to address several of the measurement limitations inherent in the personality disorder (PD) literature. In particular, we describe how IRT can be used to improve PD measurement precision, develop PD instruments, and inform PD theory. In closing, we address a key assumption of unidimensional IRT models, and address the need to move beyond these models to include multidimensional models. In this context, we outline what we see as a future direction in PD measurement. (PsycINFO Database Record (c) 2017 APA, all rights reserved).