Evaluation of the Responsiveness of the Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) Scale

BACKGROUND: The Anterior Cruciate Ligament Return to Sport After Injury (ACL-RSI) scale is a reliable and valid tool for evaluation of psychological readiness to return to sport after ACL injury, but its responsiveness to change has not been extensively evaluated. PURPOSE: To determine the responsiveness of the ACL-RSI scale. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: The ACL-RSI scale and the knee confidence question from the Knee injury and Osteoarthritis Outcome Score–Quality of Life subscale was completed at 6 and 12 months after ACL reconstruction surgery. Responsiveness was assessed using distribution and anchor-based methods for the full- and short-form versions of the scale and subgroup analyzed for sex. From distribution statistics, the standardized response mean (SRM) and the smallest detectable change (SDC) were calculated. Using the anchor-based method, the minimally important change (MIC) that was associated with an improvement in knee confidence was determined using receiver operating characteristic analysis. RESULTS: A total of 441 patients (257 men, 184 women; mean age of 25 years) were included in this study. An SRM of 0.7 was found for both versions, indicating a moderate level of responsiveness. The MIC was 13.4 points for the full-form version and 15.1 points for the short-form version. These values were larger than SDC values at the group level but not at the individual patient level. Responsiveness was similar between male and female patients. CONCLUSION: The ACL-RSI scale had sufficient responsiveness to investigate the efficacy of an intervention at a group level, but it may be more limited at an individual patient level.