Statistical Tests And Outcomes Practice Test

A 28-year-old woman (weight 62 kg) with migraine is considering Preventive Drug H. In a trial, the mean reduction in monthly migraine days was 2.1 days with Drug H vs 1.4 days with placebo; mean difference $=0.7$ days with 95% CI $0.1$ to $1.3$, $p=0.02$. How does the confidence interval impact your decision on patient treatment?

A 66-year-old man (weight 78 kg) with COPD is considering Vaccine V to prevent hospitalization from respiratory infection. In a randomized trial, hospitalization occurred in 4.5% with Vaccine V vs 6.0% with placebo; RR $=0.75$ (95% CI $0.58$ to $0.97$), $p=0.03$. Which statistical finding is most crucial for assessing drug efficacy?