The bath ankylosing spondylitis radiology index (BASRI) - A new, validatedapproach to disease assessment

Objective. To develop a reproducible and simple radiologic scoring system f or the spine in patients with ankylosing spondylitis (AS): the Bath Ankylos ing Spondylitis Radiology Index for the spine (BASRI-s), Methods. Radiographs of 470 patients with AS were scored using the New York criteria for the sacroiliac joints and, similarly, grading the lumbar and cervical spine on a scale of 0-4 (for normal, suspicious, mild, moderate, a nd severe), These 3 scores were added together to produce the BASRI-s score (scored 2-12), Radiographs of 188 patients were used to test reproducibili ty, Blinded radiographs of 89 non-AS patients were included, randomly, to a ssess disease specificity. Sensitivity to change was assessed using 177 rad iographs from 58 AS patients. Results. Intra- and interobserver variation showed 75-86% and 73-79% comple te agreement at all sites, respectively, Specificities of 0.83-0.89 suggest ed that the lumbar and cervical spine BASRI: scores were disease specific. Sensitivity to change became apparent kat 2 years (P < 0.001), Using a late ral view and an anteroposterior view of the lumbar spine was more sensitive than using a lateral view alone, Grading a set of radiographs (sacroiliac joints, lumbar spine, and cervical spine) took 30 seconds. Conclusion. BASRI is a reliable method for grading radiographic changes in patients with AS. It is disease specific, sensitive to change, valid, simpl e, and rapid to perform.