Summary

The Thai version of the SST demonstrated acceptable reliability and validity, making it a suitable patient-reported outcome measure for assessing shoulder function in Thai patients with pathologies.

Abstract

Background

The Simple Shoulder Test (SST) is a widely used patient-reported outcome measure for shoulder function. However, there is currently no Thai version of the SST.

Purpose

To cross-culturally adapt and evaluate the reliability and validity of the Thai version of the SST for patients with shoulder pathologies, using the American Shoulder and Elbow Surgeons (ASES) score as a comparison tool.

Methods

The Thai version of the SST was developed using a standard translation and cross-cultural adaptation process. A total of 75 Thai patients, comprising 73 with rotator cuff tears, 3 with combined rotator cuff tear and secondary stiff shoulder, 2 with combined rotator cuff tear and biceps tendinitis, 1 with isolated adhesive capsulitis, and 1 with isolated long head biceps tendinopathy, completed the Thai version of the SST and the ASES score. The internal consistency, test-retest reliability, and construct validity of the Thai version of the SST were assessed.

Results

Seventy-five participants, comprising 19 men and 56 women with a mean age of 63.16 years, participated in the study. The Thai version of the SST demonstrated a strong correlation with the Thai version of the ASES (r = 0.714). The test-retest reliability measures for the Thai version of the SST were good (intraclass correlation coefficient [ICC] = 0.895). The Cronbach's alpha of the Thai SST is 0.852, indicating good and acceptable internal consistency. Both the total ASES score and SST exhibited acceptable floor and ceiling effects

Conclusion

The Thai version of the SST demonstrated acceptable reliability and validity, making it a suitable patient-reported outcome measure for assessing shoulder function in Thai patients with rotator cuff tears and shoulder instability. The Thai version of the SST can be used to assess the effectiveness of interventions for these shoulder pathologies in Thai patients.