A study on weight reduction shows a p-value of 0.04 with 95% confidence interval for mean weight loss of −0.2 kg to −5.8 kg. The MOST correct interpretation is:

• A There is a 96% probability the true effect lies between −0.2 and −5.8 kg
• B 95% of individual patients lose between 0.2 and 5.8 kg
• C The probability that the null hypothesis is true is 4%
• D If the study were repeated 100 times, approximately 95 of those confidence intervals would contain the true population mean difference ✓

Explanation

A 95% confidence interval is a frequentist concept meaning that if the same study were repeated many times, 95% of constructed intervals would contain the true parameter. It does not represent a 95% probability that this specific interval contains the true mean. The p-value (0.04) tells us the probability of observing this result if the null hypothesis were true, not the probability the null is true.

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.