USMLE Step 1 biostatistics and epidemiology practice questions

10 questions · Untimed · Explanation after each question

Study designs, bias, test characteristics, risk and number-needed-to-treat calculations, hypothesis testing, confidence intervals, screening and prevention. 4–6% of Step 1.

Line drawing of a notebook with a two-by-two grid, a pencil, a ruler and a stack of journal articles

Before you start

Every question is a clinical vignette with five options and one best answer. Step 1 questions ask for the mechanism, cause or finding behind the case. After each answer you see why the key is best, a note on every option and the reference behind it. A lab values panel is one click away, as on test day.
Check each answer to see the explanation before moving on. Checked answers cannot be changed.

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Original practice questions written to the USMLE content outlines and current standard references. USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and NBME. Independent practice, not affiliated with or endorsed by the FSMB, NBME or Intealth (ECFMG).