Which of the following is a clinical statistic used to interpret meaningful change in patients?

• A. Number Needed to Treat
• B. Minimal Clinically Important Difference
• C. Minimal Detectable Change
• D. Effect Size

Answer: (B)

Focuses on a patient-centered threshold for meaningful change in outcomes. Minimal Clinically Important Difference is the smallest change in a patient-reported outcome that patients perceive as beneficial and that would lead to a change in the patient’s management. This makes it the clinically relevant benchmark for interpreting whether an observed change really matters to the patient, beyond just statistical significance. MCID is typically determined with anchor-based methods that link score changes to an external indicator of improvement, sometimes supplemented by distribution-based estimates. It’s important to note that MCID can vary by condition, baseline severity, and population. In contrast, Minimal Detectable Change concerns whether a change exceeds the instrument’s measurement error, not whether it matters clinically; Effect Size describes the magnitude of change in standardized units for study comparison but doesn’t specify patient-perceived importance; Number Needed to Treat expresses how many patients must be treated for one additional favorable outcome at the population level, not the per-patient meaningful change. So the statistic used to interpret meaningful change in patients is Minimal Clinically Important Difference.