Item Response Theory, Approach to Test Construction

Abstract

Item response theory (IRT) has had a major impact on instrument design and analysis, both in academic and clinical settings. This entry provides an introduction to the common dichotomous and polytomous IRT models and motivates the use of IRT in the test design process by comparing it with the previously dominant classical test theory. This entry provides a brief introduction to IRT to provide a foundation for the reader to develop a functional instrument within the IRT framework.