Design considerations for cases used in pharmacy teaching and learning using the case difficulty cube

Introduction: Learner-centered authentic learning opportunities in health science disciplines can be provided using cases to allow integration of theoretical knowledge across multiple subject areas and development of problem-solving skills. We have previously described the adaptation of the case difficulty cube (CDC), a model from business education, that proposes assignment of case difficulty based on three dimensions (analytical, conceptual, and presentation) in pharmacy education. Methods: The CDC for use in health science disciplines (modCDC) was evaluated using 13 cases from summative undergraduate pharmacy examinations. Inter-rater agreement (IRA) and inter-rater reliability (IRR) for modCDC ratings were first determined, then a post hoc investigation of the relationship between the modCDC score and student marks was undertaken. Results: First, the IRA for each dimension of the modCDC was adequate for aggregating ratings. IRR was excellent for the conceptual axis, good for the presentation axis, and poor for the analytical axis. Second, analysis of the relationship between the modCDC score and student marks indicated that there was a significant difference between student marks awarded at each level of case difficulty, except for the lower levels of difficulty. The results indicate that the modCDC is a relatively robust tool that could be used to determine case difficulty prior to cases being used in assessments. Conclusions: The modCDC is a simple tool that can assist academic staff in providing consistent learning opportunities for, and assessment of, pharmacy students at an appropriate level.