Item Response Theory–Based Approaches for Computing Minimum Passing Scores From an Angoff-Based Standard-Setting Study

Abstract

Even when the scoring of an examination is based on item response theory (IRT), standard-setting methods seldom use this information directly when determining the minimum passing score (MPS) for an examination from an Angoff-based standard-setting study. Often, when IRT scoring is used, the MPS value for a test is converted to an IRT-based theta ability estimate by using the test characteristic curve. The purpose of this study is to investigate some approaches to determining the MPS from an Angoff-based standard-setting study when the test questions have been calibrated using IRT methods. Although the methods studied appear to converge on the same cut score, the cut scores derived from the IRT-based approaches are all within one standard error of the Angoff-based MPS value.