Funding for this research was provided by:
European Research Council
Received: 15 September 2017
Accepted: 4 February 2018
First Online: 1 March 2018
Ethics approval and consent to participate
: Ethics approval for the SPACE cohort was given by the Ethics Committee of the Leiden University Medical Center, Leiden Amsterdam and subsequently by all participating centers. All participants gave their written informed consent.
: Not applicable.
: TW and NB share a patent on the application of CD74 antibodies in diagnosing spondyloarthritis. All other authors declare they have no competing interests.
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