A neurologist is evaluating whether to incorporate a newly approved disease-modifying therapy into their clinical practice for patients with moderate-to-severe relapsing-remitting multiple sclerosis (RRMS). To make an evidence-based decision, the physician reviews a recent phase III trial published in a prominent medical journal. The study included adult patients with RRMS who were randomly assigned in a ratio to receive either the new therapy or a placebo over a -month period.
During the study period, of the patients receiving the new therapy experienced a confirmed clinical relapse. In contrast, of the patients in the placebo group experienced a confirmed clinical relapse. The authors of the study report a relative risk of for clinical relapse ( CI, to ; ).
Based on the data provided, which of the following is the most accurate interpretation regarding the efficacy and clinical impact of this new therapy?
- AThe therapy provides a statistically significant reduction in clinical relapses, and approximately 33 patients must be treated to prevent one clinical relapse.
- BThe therapy provides a statistically significant reduction in clinical relapses, and approximately 43 patients must be treated to prevent one clinical relapse.
- CThe therapy does not provide a statistically significant reduction in clinical relapses because the 95% confidence interval for the relative risk does not include zero.
- The therapy provides a statistically significant reduction in clinical relapses, and approximately 34 patients must be treated to prevent one clinical relapse.Answer
- EThe observed reduction in clinical relapses is likely due to effect modification rather than a true treatment effect, as the relative risk is less than 1.0.