Choosing between USMLE Step 1 and its alternatives is a fork in the road for every medical student. This guide cuts through the noise — no fluff, just the facts you need to decide.
USMLE Step 1 vs NBME Subject Exams
NBME subject exams (often called "shelf exams") are end-of-rotation assessments in specific clinical disciplines like internal medicine or surgery. They test knowledge from your clerkship, not foundational sciences.
Key differences:
- Scope: USMLE Step 1 covers basic sciences (anatomy, physiology, pharmacology, etc.). NBME subject exams focus on one specialty at a time.
- Purpose: Step 1 is a licensing exam for US medical practice. Shelf exams are used by medical schools to grade clerkships.
- Scoring: Step 1 moved to pass/fail in early 2022. Shelf exams are scored on a 1–99 scale, with national percentiles.
- Impact: Step 1 pass/fail status affects residency applications differently than a numeric shelf score.
When to choose which:
- Take USMLE Step 1 if you plan to practice medicine in the US or need it for ECFMG certification.
- Use NBME subject exams to prepare for Step 2 CK or to gauge your knowledge in a specific rotation.
Take a free USMLE Step 1 demo mock to find out where you stand: Try the demo →
USMLE Step 1 vs COMLEX Level 1
COMLEX Level 1 is the osteopathic equivalent of USMLE Step 1, required for DO students. Both test basic sciences, but COMLEX includes osteopathic manipulative medicine (OMM).
Key differences:
- Format: Both are computer-based, multi-hour exams. COMLEX has more OMM questions.
- Scoring: COMLEX Level 1 is numeric (pass/fail threshold around 400). USMLE Step 1 is pass/fail.
- Recognition: USMLE is accepted by all US residency programs. COMLEX is primarily for DO residencies, though many programs accept both.
- Cost: Verify on official portals — USMLE Step 1 fees were last revised in early 2026. COMLEX fees are similar but check the NBOME site.
When to choose which:
- DO students: You must take COMLEX Level 1 for licensure. Many also take USMLE Step 1 to open more residency doors.
- MD students: USMLE Step 1 is your path. COMLEX is not relevant unless you transfer to an osteopathic program.
Decision Matrix
| Factor | USMLE Step 1 | NBME Subject Exams | COMLEX Level 1 | |---|---|---|---| | Primary audience | MD/IMGs | All med students | DO students | | Content focus | Basic sciences | Single specialty | Basic sciences + OMM | | Scoring | Pass/Fail | Numeric (1-99) | Numeric (pass ~400) | | Required for | US licensure (MD) | Clerkship grading | DO licensure | | Residency impact | High (pass/fail matters) | Low (internal use) | Moderate (DO programs) | | Cost | ~$645 (verify) | ~$60 per exam | ~$660 (verify) |
How to Decide
Your choice boils down to your career path:
- MD students or IMGs aiming for US residency: Start with USMLE Step 1. It’s non-negotiable.
- DO students: Take COMLEX Level 1. Add USMLE Step 1 if you want competitive specialties.
- For clerkship prep: NBME subject exams are useful practice, but not a substitute for Step 1.
See USMLE Step 1 mock-test packs and pricing: View plans →