A four-hour integrated teaching session on clinical decision analysis has been developed and introduced as part of the Life Long Learning Skills course for medical students at The Chinese University of Hong Kong. The feasibility and effectiveness of teaching the principles and practice of clinical decision analysis to final-year undergraduate medical students was evaluated. One hundred and thirty-two students were randomly assigned to medical (intervention) and surgical rotations (control) and were assessed two weeks before and three weeks following a teaching session. The students' performance was assessed in response to 10 A-type multiple choice question items that incorporated various clinical scenarios requiring decision making and interpreting cost-effectiveness ratios and sensitivity analysis graphs. More students in the intervention group improved their overall performance scores compared with those in the control group (23.4% vs. 7.4%; 16.1% difference; 95% confidence interval [CI], 3.8-28.5%; p = 0.01). Improvements were in interpretation of decision making (22.2% difference; 95% CI, 10.1-34.4%; p < 0.001). No improvements were seen for calculating cost-effectiveness ratios or interpreting sensitivity analysis graphs. The overall educational intervention was well received by students and effective in improving students' clinical decision analysis skills under simulated conditions.