Translation, cultural adaptation and reproducibility of the Oxford Shoulder Score questionnaire for Brazil, among patients with rheumatoid arthritis: Tradução, adaptação cultural e reprodutibilidade do questionário Oxford Shoulder Score para o Brasil em pacientes com artrite reumatoide

CONTEXT AND OBJECTIVE: Although shoulder questionnaires validated for Brazil do exist, none of them are aimed at populations with rheumatic disease. We believe that the Oxford Shoulder Score (OSS) may be useful in this population. The objective of this study was to translate the OSS, adapt it to Brazilian culture and test its reproducibility. DESIGN AND SETTING: Validation study conducted in university outpatient clinics. METHODS: The OSS was translated into Portuguese by two English teachers and was then retranslated into English by two native English teachers. These translations were reviewed by a committee to establish the version of OSS-Brazil to be administered to 30 patients with rheumatoid arthritis (RA) and shoulder pain, in order to test the cultural adaptation. The validity and reproducibility was tested among another 30 patients with RA and shoulder pain, of both genders and aged 18 to 65 years. The internal consistency and reproducibility were analyzed. The following instruments were evaluated: OSS-Brazil; a numerical scale for shoulder pain; DASH; HAQ and SF-36. RESULTS: The internal consistency was 0.957 and the intra and inter-rater reproducibility was 0.917 and 0.861, respectively. A high level of correlation was found between OSS-Brazil and the following: HAQ (-0.663), DASH (-0.731) and the SF-36 domains of functional capacity (0.589), physical aspects (0.507), pain (0.624), general state of health (0.444), vitality (0.634) and mental health (0.578). CONCLUSION: OSS-Brazil was successfully translated and adapted, and this version exhibited good internal consistency, reliability and construct validity.