Validation of the ACL-RSI Scale in Pediatric and Adolescent Patients

Abstract

Background: The Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) scale is a 12-item questionnaire assessing psychological readiness to return to sport after anterior cruciate ligament reconstruction. It has been validated for use in adults in multiple languages and in an abbreviated 6-question short form. Additionally, literature has been published using this scale in pediatric and adolescent populations, however it has not yet been validated for use with them. Purpose: To validate the ACL-RSI scale for use with pediatric and adolescent patients. Study Design: Cohort study (Diagnosis); Level of evidence, 2. Methods: Scores of 6- and 12-item ACL-RSI scales for patients undergoing return-to-sport readiness testing 6 to 8 months after anterior cruciate ligament reconstruction were analyzed. Convergent validity testing was performed against the International Knee Documentation Committee (IKDC)/Pediatric IKDC score, Single Assessment Numeric Evaluation (SANE) score, and peak torque asymmetry of knee flexion and extension using Spearman correlations. Discriminant validity testing was performed against age (Spearman correlation), body mass index (Spearman correlation), and sex (Mann-Whitney U test). Reliability testing was performed by calculating Cronbach’s alpha. Floor and ceiling effects were assessed by calculating the number of minimum and maximum scores in the cohort. Results: A total of 51 patients were included in the final analysis. The mean age at surgery was 15.2 ± 2.2 years, and 51.0% were female. The 6- and 12-item ACL-RSI scales demonstrated a strong significant positive correlation with IKDC/Pediatric IKDC scores (R = 0.723 and 0.717, respectively; P < .001) and moderate significant positive correlation with Single Assessment Numeric Evaluation scores (R = 0.516 and 0.502, respectively; P < .001) Age at surgery, body mass index, and sex were not correlated with either ACL-RSI scale. Cronbach’s alpha values of the 12- and 6-item ACL-RSI scales in this population were 0.959 and 0.897, respectively. For both the 12- and the 6-item ACL-RSI scales, no floor or ceiling effects were found as the minimum score (0) was not observed in either version, and the maximum score (100) was only observed twice (3.9%) in both versions. Conclusion: The ACL-RSI scale is valid to use with pediatric and adolescent patients. The 6-item scale may be a better choice because it has fewer redundancies and minimizes the risk of questionnaire fatigue.