BACKGROUND: Psychological readiness plays an important role in return to sport (RTS) following shoulder instability. The Shoulder Instability Return to Sport after Injury (SIRSI) scale is a validated tool designed to evaluate psychological readiness as part of the RTS decision-making process. This study aimed to translate and validate the SIRSI into German (SIRSI-D) for a German-speaking population. METHODS: SIRSI-D was developed via forward-back translation, expert synthesis, and cognitive debriefing with 20 patients. Adults with shoulder instability completed the SIRSI-D, Western Ontario Shoulder Instability Intex (WOSI), and return-to-sport surveys; SIRSI-D was re-administered after 7–10 days. Psychometric properties, including reliability, internal consistency, construct and criterion validity, and responsiveness, were evaluated per COSMIN guidelines using CFA/EFA, ICCs, Cronbach’s alpha, Pearson correlations, ROC analysis, and distribution-based MDC/MCID. RESULTS: Confirmatory and exploratory factor analyses supported a final 11-item, three-factor SIRSI-D model (chi-square = 63.10, df = 41, CFI = 0.975, RMSEA = 0.079, SRMR = 0.041); standardized loadings exceeded 0.70 except for item 2. Test–retest reliability was 0.91 and Cronbach alpha was 0.95. Convergent validity was supported by correlations with WOSI (−0.72), Subjective Shoulder Value (SSV) (0.62), and sport-specific SSV (0.67). MDC was 7.88 (individual) and 4.55 (group). Distribution-based MCID was 5.67. Area under the curve was 0.80, with an odds ratio of 1.58 per 10-point increase and cutoff of 59 points for return-to-sport. CONCLUSION: The SIRSI-D demonstrated promising psychometric properties, including acceptable reliability, internal consistency, and convergent validity, with a provisional three-factor structure requiring further validation in larger cohorts.
Schätz et al. (Fri,) studied this question.