The study is primarily comprised of a cross-sectional survey of patients who have been referred to rheumatologists with a history of back pain and are considered at high risk for spinal inflammatory arthritis because of associated conditions such as psoriasis, inflammatory bowel disease, or uveitis. The attending rheumatologist will be asked to record specific items from the routine history and physical exam in the study report form. Information from routine lab tests and diagnostic imaging will also be recorded. The aim of the study is to determine which of these items is particularly useful to be incorporated into a screening strategy for spinal arthritis which could eventually be implemented by a nurse co-ordinator. The study is non-interventional and aimed at passive collection of data that is routinely obtained in the course of clinical evaluation of patients with back pain.