Fear of Return to Sport Scale (FRESS): a new instrument for use in injured professional or recreational athletes in rehabilitation

Objective To create, develop, and validate the Fear of Return to Sport Scale (FRESS) for injured professional or recreational athletes in rehabilitation. Methods This is a questionnaire validation study. To determine the structural and construct validity, 192 injured professional or recreational athletes of different sports modalities were included. We used a subsample with 32 participants to analyze test–retest reliability and internal consistency. Main outcome measures were the FRESS, Numerical Pain Scale (NPS), Pain-Related Catastrophizing Thoughts Scale (PCTS), Self-Estimated Functional Inability because of Pain Questionnaire for athletes (SEFIP-sport), and Hospital Anxiety and Depression Scale (HADS). Results Initially, 25 questions were proposed by the specialists. Of these, 4 questions were excluded due to similarity with others. After applying the content validity coefficient, 8 questions were excluded for presenting a value lower than 0.80, leaving 13 items. The exploratory factor analysis identified the one-dimensional structure of the FRESS with 13 items. However, five items were excluded for presenting high covariance with the error of several other FRESS items in the confirmatory factor analysis. Thus, the final version of the FRESS was defined with one domain and eight items. Regarding the construct validity, we observed a magnitude of correlation varying between 0.257 and 0.470 between the FRESS and the instruments used here. We observed adequate test–retest reliability (intraclass correlation coefficient = 0.896) and internal consistency (Cronbach’s alpha = 0.868). Ceiling and floor effects were not observed. Conclusion The FRESS with one domain and eight items has acceptable measurement properties and its use in clinical and sports environments to measure the fear of returning to sport in injured professional or recreational athletes is supported.