Brazilian-Portuguese version and applicability questionnaire of the mobility index for ankylosing spondyliti.

PURPOSE To translate and adapt the Bath Ankylosing Spondylitis Methodology Index (BASMI) - a metrological measurement for the assessment of patients with ankylosing spondylitis to Brazilian-Portuguese and to analyze the applicability of the questionnaire. METHODS The Brazilian-Portuguese version of the Bath Ankylosing Spondylitis Methodology Index was achieved through a translation and back-translation process. This new Bath Ankylosing Spondylitis Methodology Index version was administered to 25 consecutive patients with ankylosing spondylitis who met the 1984 New York criteria for ankylosing spondylitis and were followed in the Soronegative Spondyloarthropathy Unit of the Rheumatology Division, São Paulo University Medical School, from May to November 2005. In order to evaluate the applicability of the questionnaire, it was administered to patients by 2 separate observers, A and B (Rheumatologists), enabling inter-observer test analysis. After 2 weeks, the second interview was administered to the same patients by observer A only to analyze the intra-observer test. All interviews were conducted in the morning. The Pearson coefficient correlation was used to evaluate applicability. RESULTS There was no conflict stemming from translation and re-translation of Bath Ankylosing Spondylitis Methodology Index questionnaire, and cross-cultural adaptation proved unnecessary. All components had statistically significant coefficients for intra- and inter-observational applicability, with scores ranging from 0.85 to 1.00 and 0.80 to 0.94, respectively. DISCUSSION The Brazilian-Portuguese version of the Bath Ankylosing Spondylitis Methodology Index proved to be an applicable instrument for analyzing the mobility index of Brazilian patients with ankylosing spondylitis.