Validation and reliability of a Spanish version of Simple Shoulder Test (SST-Sp).

Background: The Simple Shoulder Test (SST-Sp) is a widely used outcome measure. Objective: The purpose of this study was to develop and validate a Spanish-version SST (SST-Sp). Methods: A two-stage observational study was conducted. The SST was initially cross-culturally adapted to Spanish through double forward and backward translation and then validated for its psychometric characteristics. Participants ( n = 66) with several shoulder disorders completed the SST-Sp, DASH, VAS and SF-12. The full sample was employed to determine factor structure, internal consistency and concurrent criterion validity. Reliability was determined in the first 24-48 h in a subsample of 21 patients. Results: The SST-Sp showed three factors that explained the 56.1 % of variance, and the internal consistency for each factor was α = 0.738, 0.723 and 0.667, and reliability was ICC = 0.687-0.944. The factor structure was three-dimensional and supported construct validity. Criterion validity determined from the relationship between the SST-Sp and DASH was strong ( r = −0.73; p < 0.001) and fair for VAS ( r = −0.537; p < 0.001). Relationships between SST-Sp and SF-12 were weak for both physical ( r = −0.47; p < 0.001) and mental ( r = −0.43; p < 0.001) dimensions. Conclusions: The SST-Sp supports the findings of the original English version as being a valid shoulder outcome measure with similar psychometric properties to the original English version. [ABSTRACT FROM AUTHOR]