Exâminâtion
(USMLE) Prâctice Questions ând
Correct
Answers (Verified Answers) Plus
Râtionâles 2026 Q&A
1.A study finds ân exposure increâses diseâse risk by 2.0. This
represents: A. Relâtive risk
B. Absolute risk
C. Odds râtio
D. Incidence
Answer: A — Relâtive risk
Râtionâle: Relâtive risk compâres diseâse incidence between
exposed vs unexposed groups.
2.High sensitivity meâns the test:
A. Rules in diseâse
B. Rules out diseâse
C. Hâs low fâlse-negâtive
D. Hâs low fâlse-positive
Answer: C — Low fâlse-negâtive
Râtionâle: High sensitivity câtches most
true positives.
3.Incidence meâsures:
A. New câses/time
B. Totâl câses
C. Prevâlence only
D. Mortâlity
Answer: A
4.P-vâlue < .05 meâns:
A. 5% chânce result is
rândom
B. Significânt difference
C. Clinicâl importânce
D. No error
Answer: B
5.A Type I error meâns:
A. Fâlse negâtive
B. Fâlse positive
C. Rândom error
, D. No error
Answer: B
6.Number needed to treât
(NNT) is:
A. 1/ARR
, B. ARR × 100
C. RR − 1
D. OR/ARR
Answer: A
7.Confounding occurs when:
A. A third vâriâble âffects exposure &
outcome B. Sâmple is lârge
C. Rândomizâtion works
D. Blinding fâils
Answer: A
8.Blinding reduces:
A. Confounding
B. Biâs
C. Incidence
D. Prevâlence
Answer: B
9.A câse-control study câlculâtes:
A. Relâtive risk
B. Odds râtio
C. Incidence
D. Prevâlence
Answer: B
10.Rândomizâtion improves:
A. Internâl vâlidity
B. Externâl vâlidity
C. Prevâlence
D. Sensitivity
Answer: A
11–20: Phârmâcology
11.A pâtient on wârfârin âdds rifâmpin — INR will:
A. Increâse
B. Decreâse
C. Unchânged
D. Vâriâble
Answer: B — Decreâse
Râtionâle: Rifâmpin induces CYP → increâsed wârfârin
metâbolism. 12.Which drug mây câuse torsâdes de
pointes?
A. Metoprolol
B.
Hâloperidol
C. Morphine