A general diagnostic modelling framework for forced-choice assessments

Diagnostic classification modelling (DCM) is a family of restricted latent class models often used in educational settings to assess students' strengths and weaknesses. Recently, there has been growing interest in applying DCM to noncognitive traits in fields such as clinical and organizational psychology, as well as personality profiling. To address common response biases in these assessments, such as social desirability, Huang (2023, Educational and Psychological Measurement, 83, 146) adopted the forced-choice (FC) item format within the DCM framework, developing the FC-DCM. This model assumes that examinees with no clear preference for any statements in an FC block will choose completely at random. Additionally, the unique parametrization of the FC-DCM poses challenges for integration with established DCM frameworks in the literature. In the present study, we enhance the capabilities of DCM by introducing a general diagnostic framework for FC assessments. We present an adaptation of the G-DINA model to accommodate FC responses. Simulation results show that the G-DINA model provides accurate classifications, item parameter estimates and attribute correlations, outperforming the FC-DCM in realistic scenarios where item discrimination varies. A real FC assessment example further illustrates the better model fit of the G-DINA. Practical recommendations for using the FC format in diagnostic assessments of noncognitive traits are provided.