Pocock SJ, Stone GW. The Primary Outcome Is Positive – Is That Good Enough? The New England journal of medicine. 375(10):971-9. 2016. PMID: 27602669 [free full text]
The key questions to ask when a trials primary outcome is positive:
- Is a P value less than 0.05 good enough?
- What is the magnitude of the treatment benefit?
- Is the primary outcome clinically important (and internally consistent)?
- Are secondary outcomes supportive?
- Are the principal findings consistent across important subgroups?
- Is the trial large enough to be convincing?
- Was the trial stopped early?
- Do concerns about safety counterbalance positive efficacy?
- Is the efficacy–safety balance patient-specific?
- Are there flaws in trial design and conduct?
- Do the findings apply to my patients?