To the Editor In clinical trial design, the minimal clinically important difference (MCID) is used in sample size calculations to ensure enough statistical power to detect the smallest difference needed to justify changing patient treatment. Unfortunately, because these calculations are based on probabilities of hypothetical findings, clinical trials can produce statistically significant results for differences smaller than those considered clinically important. To avoid implementing changes based on statistical differences that are not clinically meaningful, it is important to consider if the MCID falls within the 95% CI of the effect estimate.1