Psychometric Evaluation of Unfolding Case Studies for Clinical Judgment Assessment

Background and Purpose: Unfolding case studies offer promising approaches for assessing clinical judgment in nursing education, but concerns about efficiency and item dependency have limited their adoption in high-stakes examinations. This study evaluated response time patterns and psychometric properties of unfolding case studies in operational nursing licensure assessment contexts. Methods: Two complementary analyses used the National Council Licensure Examination for Registered Nurses examination data. Study 1 compared response times between unfolding cases and equivalent standalone items (N = 54,519). Study 2 examined item dependency using Yen's Q_{3, *} statistic in operational pretest conditions (N = 91,518). Results: Unfolding cases showed initial time costs (23.5% increase) followed by substantial efficiency gains (39% average reduction) across subsequent items, with very large effect sizes (Cohen's d = 2.37). Item dependency analysis revealed minimal statistical dependence (Q_{3, *} median = 0.107), indicating maintained local independence assumptions. Conclusions: Unfolding case studies demonstrate both practical efficiency advantages and psychometric soundness in high-stakes assessment contexts, supporting their broader integration in nursing assessments while maintaining rigorous measurement standards.