Minimal Clinically Important Difference DefiningWhat Really Matters to Patients

When assessing the clinical utility of therapies intended to improve subjective outcomes, the amount of improvement that is important to patients must be determined.1 The smallest benefit of value to patients is called the minimal clinically impor-tant difference (MCID). The MCID is a patient-centered concept, capturing both the magnitude of the improvement and also the value patients place on the change. Using patient-centered MCIDs is important for studies involving patient-reported outcomes,2 for which the clinical importance of a given change may not be obvious to clinicians selecting treatments. The MCID defines the smallest amount an outcomemust change to be meaningful to patients.1 In this issue of JAMA, Hinmanet al3 report findings froma clini