USMLE® Step 2 CK · chapter BIO

Biostatistics & Epidemiology: USMLE® Step 2 CK topics

19 topics. Each one opens a review page with its guideline basis and key clinical sections, then links the QuestionBank questions, ChartWalk flowchart, FlashCards and ImageBank plates that share its code.

1. Choosing the correct statistical test

   BIO-STAT-039 questions · Review Book p. 82 · 2022 USMLE® Step 2 CK Content Outline

2. Confounding, effect modification & statistical adjustment

   BIO-CONF-0140 questions · Review Book p. 78 · 2022 USMLE® Step 2 CK Content Outline

3. Drug advertisements & medical literature/abstract interpretation

   BIO-LIT-019 questions · Review Book p. 86 · 2022 USMLE® Step 2 CK Content Outline; Bekelman et al. JAMA 2003

4. Experimental studies — RCT design, randomization & blinding

   BIO-STUDY-0218 questions · Review Book p. 67 · Consolidated Standards of Reporting Trials 2025 Statement

5. Hypothesis testing — type I/II error, p-value, alpha

   BIO-STAT-0127 questions · Review Book p. 79 · 2022 USMLE® Step 2 CK Content Outline

6. Information/measurement bias — recall, observer, Hawthorne

   BIO-BIAS-0211 questions · Review Book p. 77 · 2022 USMLE® Step 2 CK Content Outline

7. Likelihood ratios & Bayesian pre-/post-test probability

   BIO-TEST-027 questions · Review Book p. 73 · 2022 USMLE® Step 2 CK Content Outline

8. Measures of disease frequency — incidence & prevalence

   BIO-MEAS-0123 questions · Review Book p. 68 · 2022 USMLE® Step 2 CK Content Outline

9. Measures of risk & treatment effect — RR, OR, NNT

   BIO-MEAS-0222 questions · Review Book p. 70 · Consolidated Standards of Reporting Trials 2025 Statement

10. Meta-analysis, systematic review & levels of evidence

    BIO-EBM-0111 questions · Review Book p. 83 · Cochrane Handbook for Systematic Reviews of Interventions v6.5 (2024), ch 10, 13 + 14

11. Observational study designs — cohort, case-control, cross-sectional

    BIO-STUDY-0120 questions · Review Book p. 66 · 2022 USMLE® Step 2 CK Content Outline; Grading of Recommendations Assessment, Development and Evaluation evidence hierarchy

12. Quality improvement, patient safety & error reporting

    BIO-QI-016 questions · Review Book p. 87 · 2022 USMLE® Step 2 CK Content Outline; Institute for Healthcare Improvement PDSA Model

13. Screening program criteria & lead-/length-time bias

    BIO-SCREEN-0147 questions · Review Book p. 74 · USPSTF Procedure Manual; UK NSC screening criteria (2022); WHO screening guide (2020)

14. Selection bias — sampling, nonresponse & Berkson

    BIO-BIAS-0130 questions · Review Book p. 75 · 2022 USMLE® Step 2 CK Content Outline; Cochrane Risk of Bias Tool

15. Social determinants of health & health disparities

    BIO-SDOH-012 questions · Review Book p. 89 · Healthy People 2030 SDOH Framework

16. Statistical power & sample size determination

    BIO-STAT-0230 questions · Review Book p. 81 · 2022 USMLE® Step 2 CK Content Outline

17. Study validity — internal/external validity, ITT vs per-protocol

    BIO-VALID-0126 questions · Review Book p. 85 · 2022 USMLE® Step 2 CK Content Outline

18. Survival analysis — Kaplan-Meier curves & hazard ratio

    BIO-SURV-0110 questions · Review Book p. 83 · 2022 USMLE® Step 2 CK Content Outline

19. Test performance — sensitivity, specificity & predictive values

    BIO-TEST-0127 questions · Review Book p. 71 · 2022 USMLE® Step 2 CK Content Outline; 2015 Standards for Reporting of Diagnostic Accuracy Guideline

Written and clinically reviewed by TheCodexes.com (editorial policy). Guideline citations are the primary sources each topic follows.