Epidemiology & Prevention USMLE Step 1 Practice Question
A case-control study examines the relationship between oral contraceptive use and venous thromboembolism (VTE) in women aged 25-45 years. Researchers enroll 200 women with newly diagnosed deep vein thrombosis confirmed by compression ultrasound and 400 age-matched controls without VTE history. Chart review reveals that 80 of the cases used oral contraceptives, while 60 of the controls used oral contraceptives. All participants were ambulatory without recent surgery or prolonged immobilization. Which of the following best describes the odds ratio for the association between oral contraceptive use and VTE?
Answer choices
- A0.75
- B1.33
- C1.87
- D2.13Correct answer
- E3.42
- F4.67
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