Using standardized video cases for assessment of medical communication skills: reliability of an objective structured video examination by computer.

ABSTRACT

OBJECTIVE: Using standardized video cases in a computerized objective structured video examination (OSVE) aims to measure cognitive scripts underlying overt communication behavior by questions on knowledge, understanding and performance. In this study the reliability of the OSVE assessment is analyzed using the generalizability theory. METHODS: Third year undergraduate medical students from the Academic Medical Center of the University of Amsterdam answered short-essay questions on three video cases, respectively about history taking, breaking bad news, and decision making. Of 200 participants, 116 completed all three video cases. Students were assessed in three shifts, each using a set of parallel case editions. About half of all available exams were scored independently by two raters using a detailed rating manual derived from the other half. Analyzed were the reliability of the assessment, the inter-rater reliability, and interrelatedness of the three types of video cases and their parallel editions, by computing a generalizability coefficient G. RESULTS: The test score showed a normal distribution. The students performed relatively well on the history taking type of video cases, and relatively poor on decision making and did relatively poor on the understanding ('knows why/when') type of questions. The reliability of the assessment was acceptable (G = 0.66). It can be improved by including up to seven cases in the OSVE. The inter-rater reliability was very good (G = 0.93). The parallel editions of the video cases appeared to be more alike (G = 0.60) than the three case types (G = 0.47). DISCUSSION: The additional value of an OSVE is the differential picture that is obtained about covert cognitive scripts underlying overt communication behavior in different types of consultations, indicated by the differing levels of knowledge, understanding and performance. The validation of the OSVE score requires more research. CONCLUSION AND PRACTICE IMPLICATIONS A computerized OSVE has been successfully applied with third year undergraduate medical students. The test score meets psychometric criteria, enabling a proper discrimination between adequately and poorly performing students. The high inter-rater reliability indicates that a single rater is permitted.