USMLE Step 1 assesses whether medical school students or graduates understand and can apply important concepts of the basic sciences to the practice of medicine. Step 1 ensures mastery of not only the sciences that provide a foundation for the safe and competent practice of medicine in the present, but also the scientific principles required for maintenance of competence through lifelong learning. Step 1 is constructed according to an integrated content outline that organizes basic science material along two dimensions: system and process. It includes the following subjects: Anatomy, Behavioral sciences, Biochemistry, Microbiology, Pathology, Pharmacology, Physiology, Interdisciplinary topics, such as nutrition, genetics, and aging.
Step 1 is a one-day examination. It is divided into seven 60-minute blocks and administered in one 8-hour testing session. The number of questions per block on a given examination form will vary, but will not exceed 40. The total number of items on the overall examination form will not exceed 280.
US medical students take Step 1 at the end of the Basic Sciences portion of the curriculum, usually after the second year of medical school. The Step 1 score is frequently used in medical residency applications as a measure of a candidate’s likelihood to succeed in that particular residency (and on that specialty’s board exams), and it has been cited by residency program directors as their most important criterion in selecting graduating medical students for their residency program. Average USMLE Step 1 scores for various residencies are available in Charting Outcomes in the Match.
If the student passes the exam, he or she may not repeat it to achieve a higher score, and any failed attempt is permanently recorded. This “one-time deal” situation is the reason the Step 1 is broadly viewed as the most arduous and paramount examination a medical student will ever sit during his or her career. It has substantial bearing on the specialties and location a residency applicant is competitive for.