A 10-year prospective cohort study enrolls 10,000 current smokers (mean age 55, smoking ≥1 pack daily for ≥30 years) and 10,000 age-matched never-smokers to assess lung cancer risk. At baseline, spirometry shows FEV1/FVC ratio of 0.68 in smokers versus 0.82 in never-smokers. During the 10-year follow-up period, 200 smokers are diagnosed with histologically-confirmed lung adenocarcinoma compared to 20 never-smokers. Occupational asbestos and radon exposure are similar between groups. Which of the following best represents the relative risk of lung cancer in smokers compared to never-smokers?
- A)0.1
- B)1.8
- C)10.0GABARITO
- D)18.0
- E)20.0
Explicação
Relative risk (RR) is calculated as the risk (incidence rate) in the exposed group divided by the risk in the unexposed group. Risk in smokers = 200/10,000 = 0.02 or 2%. Risk in never-smokers = 20/10,000 = 0.002 or 0.2%. Therefore, RR = 0.02/0.002 = 10.0. This... Ver explicação completa e trilha adaptativa →