USMLE Step 1 Syllabus: The Complete Content Outline

“Syllabus” isn’t the official term, but it’s what most students mean when they ask what Step 1 actually covers. The real document is the USMLE Step 1 Content Outline, published directly by the NBME and FSMB, and it breaks the exam down three different ways at once: by organ system, by discipline, and by physician task. This guide walks through all three, with the exact percentage ranges from the official outline.

What the Step 1 syllabus actually is

Every Step 1 question is tagged along three separate axes simultaneously: a system (which organ system or process the question is about), a discipline (which basic science field it draws on), and a physician task (what kind of reasoning it’s testing). A single cardiology question about a drug’s mechanism could count toward the cardiovascular system, pharmacology as a discipline, and medical knowledge as a task, all at once.

The systems breakdown

The system breakdown tells you which organ systems and processes get the most questions, regardless of what discipline the question is drawing from.

The disciplines breakdown

The discipline breakdown tells you which basic science field a question is drawing its reasoning from, independent of which organ system it happens to be about.

The physician task breakdown

The physician task breakdown tells you what kind of thinking a question is actually asking you to do, separate from the subject matter entirely.

What this means for how you study

Three things stand out once you see the actual numbers instead of guessing at them.

• Pathology and Physiology dominate the discipline axis. At 45 to 55% and 30 to 40% respectively, these two disciplines alone can account for the reasoning behind most questions on the exam, regardless of which organ system they are attached to. If your review time is limited, these are the two disciplines where depth matters most.
• No single organ system dominates the way Pathology dominates disciplines. The highest system category, Reproductive & Endocrine, tops out at 16%, and the spread across systems is much flatter than the spread across disciplines. Skipping an entire organ system is a riskier bet than skipping depth in a smaller discipline like Genetics.
• Most of the exam is still foundational science, not management. Even though Step 1 is written entirely as clinical vignettes, 60 to 70% of it is classified as applying foundational science concepts, not diagnosis or patient management. The vignette format tests how you apply basic science, not how you run a clinic.

If you want a week-by-week plan that actually reflects this weighting, our Step 1 study guide includes a sample dedicated-period schedule, and our 8 things to know about Step 1 covers the exam’s rules and policies that the content outline does not.

Frequently asked questions

Is "content outline" the same thing as "syllabus"?

Close enough for practical purposes. USMLE’s own term is the Content Outline and Specifications, published by the NBME and FSMB. Most students just call it the syllabus or the blueprint.

Why do the percentages in different tables not add up to 100% together?

Because systems, disciplines and physician tasks are three separate, overlapping ways of classifying the same set of questions, not three different sets of questions. Each table sums to roughly 100% on its own.

What is the single most heavily tested discipline on Step 1?

Pathology, at 45 to 55% of the exam, by a wide margin over every other discipline on the official outline.

What is the single most heavily tested organ system on Step 1?

Reproductive & Endocrine Systems, at 12 to 16%, though the spread across systems is much flatter than the spread across disciplines, so no single system dominates the way Pathology does.

What about the Step 2 CK syllabus?

See our Step 2 CK syllabus guide for the same breakdown applied to Step 2 CK, which replaces Step 1’s discipline axis with a clinical science axis organized by rotation.

What about the Step 3 syllabus?

See our Step 3 syllabus guide for the same breakdown applied to Step 3, which drops the discipline axis entirely and shifts heavily toward diagnosis and management instead of foundational science.

Does the content outline ever change?

The NBME and FSMB can update it, so treat the figures here as a snapshot and confirm the current outline directly on USMLE.org before building a study plan around exact percentages.

Sources and disclaimers

Percentage ranges are taken directly from the USMLE Step 1 Content Outline and Specifications, published by the NBME and FSMB at usmle.org, checked on October 1, 2026. These figures are set by the USMLE program and can change, so confirm the current outline directly on USMLE.org before relying on it for exam preparation. MedPrep Institute is not affiliated with or endorsed by NBME, FSMB or USMLE. All trademarks belong to their owners.