Using Computerized Patient Simulations to Measure the Clinical Competence of Physicians

The National Board of Medical Examiners is developing a computer-based patient-simulation examination (CBX) to be used in the evaluation of the clinical competence of physicians. The Rasch partial credit model (RPCM; Masters, 1982; Wright & Masters, 1982) is used to scale examinee performance on the simulated patient case. This article describes the scoring and scaling of a CBX case to demonstrate how the RPCM can be used (a) to increase the quality of the examination by detecting errors in scoring logic and (b) to construct an explicit performance-based definition of the person measures for use in standard setting.