J Rheumatol 2019 02 1;46(2):145-152. Epub 2018 Nov 1.
From the Epidemiology Group, School of Medicine, Medical Sciences and Nutrition, and the Aberdeen Centre for Arthritis and Musculoskeletal Health, and the Medical Research Council (MRC)/Arthritis Research UK Centre for Musculoskeletal Health and Work, University of Aberdeen, Aberdeen, UK; MRC Lifecourse Epidemiology Unit, University of Southampton, Southampton, UK; Spondylitis Program, Department of Rheumatology, Toronto Western Hospital, University Health Network, Toronto, Ontario, Canada.