Reliability, validity, and feasibility of the objective structured clinical examination in assessing clinical skills of final year surgical clerkship

OBJECTIVE: To report our experience with measurements of the objective structured clinical examination (OSCE) conducted for the final surgical clerkship year.

METHODS: A pilot study of the OSCE was conducted on 64 students split over 2 consecutive days lasting 160 minutes each day in May 22-23, 2005 at the Department of Surgery, College of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia. There were 24 actual stations in day one and 22 in day 2, consisting of combinations of history taking/communication skills, physical examination skills, and problem solving skills.

RESULTS: The stability of the OSCE measured by Cronbach's alpha on day one was 0.68 and 0.79 on day 2. The internal consistency of the OSCE measured by Carmine's theta on day one was 0.79 and 0.81 on day 2. Credibility and comprehensiveness of the OSCE were considered good by both staff and students. Accuracy of the OSCE measured by Pearson's correlation with the MCQs was 0.5.

CONCLUSION: The OSCE proved to be reliable, and a valid format for testing the clinical skills of final surgical clerkship year. Feasibility of the OSCE can be further improved with experience, repetitions, and use of standardized patients.