Step 3 is the final exam of the USMLE series. Step 2 focuses more on clinical science applicants. Students generally take Step 2 during the third or fourth year of medical school. Step 1 is an exam that most medical students take in their second or third year of school, which tests basic science knowledge relevant to the practice of medicine.

The USMLE Step exams are one of the most important and anxiety-inducing aspects of medical training.