A clinical trial reports a p-value of 0.03 for the primary outcome. The most accurate interpretation is:
- A There is a 3% probability of observing this extreme or more extreme result if the null hypothesis were true ✓
- B There is a 3% probability that the null hypothesis is true
- C There is a 97% probability that the treatment is effective
- D The absolute risk reduction is 3%
Correct answer: A. There is a 3% probability of observing this extreme or more extreme result if the null hypothesis were true
Explanation
A p-value is the probability of observing a result as extreme as or more extreme than the observed data, assuming the null hypothesis is true. A p-value of 0.03 does NOT mean there is a 3% probability that the null hypothesis is true (that is a Bayesian posterior probability). It means: if the null hypothesis were true, the probability of obtaining this result by chance is 3%. Statistical significance does not imply clinical importance.
Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.