The human ability for self-consciousness—the capacity to reflect on oneself and to think about one’s thoughts, experiences, and actions—is central to understanding personality and motivation. The present research examined the psychometric properties of the Self-reflection and Insight Scale (SRIS), a prominent self-report scale for measuring individual differences in private self-consciousness. Using tools from Rasch and item response theory models, the SRIS was evaluated using responses from a large sample of young adults (n = 1192). The SRIS had many strengths, including essentially zero gender-based differential item functioning (DIF), but a cluster of poor performing items was identified based on item misfit, high local dependence, and low item difficulty and discrimination. Based on the IRT analyses, a concise 12-item scale, evenly balanced between self-reflection and insight, was crafted. The short SRIS showed strong dimensionality, reliability, item fit, and local independence as well as essentially no gender DIF. Taken together, the many psychometric strengths of the SRIS support its popularity, and the short form will be useful for research and applied contexts where an efficient, concise version is needed.
Application of the mixture item response theory model to the Self-Administered Food Security Survey Module for Children