An internal medicine residency program is holding an evidence-based medicine journal club. The residents are reviewing methodology excerpts from five recent clinical trials to evaluate their validity, potential biases, and clinical applicability. Match each trial methodology excerpt to the corresponding epidemiological or statistical concept it best describes.
- Data analysis was restricted only to those participants who took at least 80% of their assigned medication and completed all scheduled clinic visits.Per-protocol analysis
- All randomized subjects were included in the final statistical model according to their original group assignment, regardless of subsequent noncompliance, crossover, or withdrawal.Intention-to-treat analysis
- Because the primary composite outcome was not statistically significant, the authors subsequently stratified the cohort by baseline symptom severity and reported a benefit solely in the 'severe' group.Post-hoc subgroup analysis
- The trial was powered to demonstrate that the new once-weekly injection preserves bone density no worse than the standard daily oral medication by a pre-specified margin of 1.5%.Non-inferiority design
- The investigators assessed the efficacy of the new lipid-lowering agent by measuring the reduction in LDL cholesterol at 6 months, rather than tracking 5-year myocardial infarction rates.Surrogate endpoint
Answer
1 matches Per-protocol analysis; 2 matches Intention-to-treat analysis; 3 matches Post-hoc subgroup analysis; 4 matches Non-inferiority design; 5 matches Surrogate endpoint.
Each excerpt perfectly illustrates a foundational concept in medical literature interpretation. Understanding these concepts is critical for physicians to accurately evaluate the validity of clinical trials and the applicability of drug advertisements to patient care.
Step-by-Step Solution
Key Concept
Methodological principles in clinical trial design and analysis.
Estimated Time:2m 0s