1 *Arthritis Research UK Primary Care Centre, Primary Care Sciences, Keele University, Keele, Staffordshire, United Kingdom †Musculoskeletal Division, The George Institute for Global Health, University of Sydney, Australia and EMGO+ Institute, VU University Medical Centre, Amsterdam, the Netherlands; and ‡Spine Centre of Southern Denmark, Hospital Lillibælt, Institute of Regional Health Services Research, University of Southern Denmark, Odense, Denmark.