Measurement properties of translated versions of the Scoliosis Research Society-22 Patient Questionnaire, SRS-22: a systematic review.

PURPOSE: The Scoliosis Research Society-22 Patient Questionnaire (SRS-22) has been translated into various languages and tested in patients with scoliosis. However, the translations and their psychometric properties have never been systematically reviewed. This study aimed to evaluate the psychometric properties and to provide the current level of evidence of all the available translations of the SRS-22 using the "COnsensus-based Standards for the selection of health status Measurement INstruments" (COSMIN). METHODS: A systematic review was performed. The PubMed, Medline, EMbase, and CINAHL databases were searched for articles concerning the translations of the SRS-22 and/or evaluating any of their measurement properties. Two reviewers independently assessed the methodological quality and the psychometric estimates of the selected studies by using the 4-point rating scale COSMIN checklist and a validated quality assessment criteria, respectively. The level of evidence of each psychometric property per language was determined combining COSMIN outcomes and psychometric results. RESULTS: The search strategy led to 24 articles evaluating the SRS-22 in 17 different languages. The methodological quality of the properties was mostly poor to fair, and there was a lack of information regarding them. The overall assessment was positive in 42.5 % of cases. The level of evidence resulted in a limited positive evidence in 11 languages. CONCLUSIONS: The Chinese (traditional), Dutch, Italian, Norwegian, and Spanish translations are advisable; the Greek, Japanese, Korean, Persian, Thai, and Turkish translations showed encouraging results but should be used with caution; the Brazilian, Chinese (simplified), Polish, and Swedish translations showed contradictory or scarce results, and no suggestions can be formulated; the French Canadian and German translations did not provide methodologically sound information. Further attention should be given to cross-cultural and structural validity, hypothesis testing, and responsiveness.