MRC/Arthritis Research UK Centre for Musculoskeletal Health and Work (grant no: 20665 CI KW-B). The BSRBR-AS is funded by the British Society for Rheumatology who have received funding for this from Pfizer, AbbVie and UCB. These companies receive advance copies of manuscripts for comments. They have no input in determining the topics for analysis or work involved in undertaking it.Peer reviewedPostprin