Journal Club Summary

Methodology Score: 2.5/5              
Usefulness Score: 2/5
Gouin S, Vo TT, Roy M, Lebel D, Gravel J.
Pediatrics. 2012 Jun;129(6):1050-5.
This randomized, double-blinded, placebo-controlled trial of 144 children in Montreal found that the prescription of oral dimenhydrinate did not significantly decrease the frequency of vomiting in children with acute gastroenteritis compared with placebo (treatment failure rates 31% and 29%, respectively; absolute difference 0.02; CI 0.12-0.17). Journal Club attendees felt that despite this study’s generalizability to our own local pediatric ED population, methodological flaws limited its usefulness (low power, unequal baseline characteristics, and multiple potential sources of bias).
By: Dr. Tighe Crombie
(Presented June 2013)

Epi Lesson: Sample Size in Clinical Trials  

All intervention studies should indicate how the sample size was estimated including the desired alpha error (usually 0.05), power (usually 80-90%), and expected outcome rate in the control group. Most important is a statement of the minimal clinically important difference (MCID) that would have to be shown by the study intervention for clinicians to accept the new treatment as better. In an effort to keep sample size low, investigators sometimes estimate an MCID much larger than is reasonable. By: Dr. Ian Stiell