Purpose: Emotional development, an important component of nascent professional competence, is likely to be shaped by specific formative experiences. This study sought to identify and gauge the impact of highly evocative experiences occurring during medical school.

Method: A 34-item list of candidate formative experiences was developed through focus group meetings of "colleges program"-affiliated student-advising faculty. The resulting survey instrument was administered to 216 graduating medical students at the Johns Hopkins University School of Medicine in 2007 and 2008 in a cohort study. Primary outcomes were exposure rates for the experiences and students' ratings of impact for those that occurred.

Results: One hundred eighty-one students (84%) responded. All events were experienced by >25% of students. Two events were described by most as having tremendous impact: "finding an exceptional role model" and "identifying a perfect area of medicine." Other prevalent events with strong impact included "a special patient-care experience," "working well with a team," "seeing a patient whose life was saved," "encountering a negative role model," "seeing a patient die," "seeing a patient experience severe pain," and "a bad clinical experience." Factor analysis revealed three event clusters: "inspiring experiences," "mortality-related experiences," and "negative experiences relating to the learning environment."

Conclusions: Specific formative experiences have especially strong impacts on medical students. Whereas the intrinsic value of such experiences should continue to drive educational design, increased awareness of the diversity and range of formative experiences will prepare educators to more effectively guide positive emotional development, enhancing personal and professional growth during medical school.