Minimal clinically important difference (MCID) and other measures of minimum clinical importance are increasingly recognized as important clinical considerations for evaluating the efficacy of an intervention. As our interpretation of clinical outcome evolves beyond statistical significance, psychometric properties such as MCID will be increasingly important to various stakeholders in the orthopaedic community. The purpose of this study was to: 1) describe the state of clinically important outcome reporting and 2) describe the methods used to derive these psychometric values for sports medicine patients undergoing operative treatments.
A review of the MEDLINE database was performed. Studies primarily deriving and reporting clinically important outcome measures for operative interventions in sports medicine were included. Demographic, methodological and psychometric properties of included studies were extracted. Level of Evidence and the Newcastle Ottawa Scale (NOS) were used to assess study quality. Statistical analysis was primarily descriptive.
Fifteen studies met inclusion criteria; 10 of the 15 studies were Level II evidence and mean NOS score was 5.3/9. Minimal detectable change (MDC) was the most commonly derived measure of clinical importance, calculated in 53.3% of studies, followed by MCID, calculated in 40.0% of studies. A combination of distribution and anchor-based methods was the most commonly used method to determine clinical importance (N = 7, 46.7%) followed by distribution only (N = 5, 33.3%). Predictors of clinically important change were reported in four studies and were most commonly related to pre-operative functional score.
MDC and the MCID are the most commonly reported measures of clinically important outcome after operative treatment in sports medicine. A combination of both distribution and anchor-based methods is commonly used to derive these values. More attention should be paid to reporting outcomes that are clinically important and developing guidelines for reporting clinical meaningful outcome.