Cross-cultural adaptation and validation of the Chinese version of the shoulder pain and disability index in patients with symptomatic shoulder pain A prospective case series

The aim of this study is to cross-culturally adapt and translate the original version of SPADI into Chinese (C-SPADI), and to test the reliability, validity, and responsiveness of the C-SPADI. This research was a test of previously developed diagnostic criteria in a series of consecutive patients with universally applied gold standard. The original version was translated into Chinese according to international recognized standards. Patients who were diagnosed with a shoulder disorder and underwent shoulder arthroscopic treatments from 2014 to 2015 were enrolled in our study. Each participant was asked to finish the C-SPADI, the Short-Form 36 (SF-36), and the Oxford Shoulder score (OSS) at first visit. The C-SPADI was completed a second time with an interval of 7 days. Six months after arthroscopic treatments, the C-SPADI was completed a third time for responsiveness evaluation. The Cronbach alpha, intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimally detectable change (MDC), Pearson correlation coefficient (r), effect size (ES), and standardized response mean (SRM) were calculated to evaluate the reliability, validity, and responsiveness of C-SPADI respectively. The original version of the SPADI was well adapted and translated into Chinese. The Cronbach alpha ranged from 0.812 to 0.912 in all subscales and total scale of the C-SPADI, indicating good or excellent internal consistency. The test retest reliability (ICC = 0.8870.915, SEM = 5.47, MDC = 15.16) was proved to be good or excellent. Moderate or good correlations (r = 0.556-0.672) were obtained between the C-SPADI and the OSS, physical subscales of SF-36; and poor, fair, or moderate correlations (r = 0.038-0.492) were obtained between the C-SPADI and mental subscales of SF-36, which, adequately illustrated good discriminant validity in the C-SPADI. Additionally, the responsiveness was considered good in the C-SPADI (SRM = 1.58-2A4, ES = 1.79-2.17). The C-SPADI was documented to be a reliable, valid, and responsible instrument for self-assessment of patients with shoulder disorders in China. Level of Evidence: Level II.