Prospective measurement of a problem-based learning course sequence.

Objective: To measure the effect, over time, of a 2-year problem-based learning (PBL) sequence on the skills, knowledge, and abilities it was designed to develop and enhance.

Design: At the start of each PBL semester, students were provided a "work sample" case with a main medical issue not previously covered in the curriculum. A standardized form containing 6 sections (hypotheses, learning issues to investigate, how hypotheses ruled in/out, primary-problem identification, plan, and goals of plan) was completed for each case. To rate student performance, investigators used a standardized form with 5-point Likert scale.

Assessment: Sixty-seven students who completed 4 assessments were included in data analyses. Scores significantly improved for each semester compared with baseline. Minimal significant differences were observed among semesters 2, 3, and 4.

Conclusion: The 2-year PBL sequence improved students' performance compared with baseline, but the performance ceiling observed in our study requires further investigation.