Funding for this research was provided by:
Received: 12 September 2018
Accepted: 31 May 2019
First Online: 13 June 2019
Change Date: 20 August 2019
Change Type: Correction
Change Details: An error occurred during the publication of a number of articles in <i>BMC Rheumatology</i>. Several articles were published in volume 3 with a duplicate citation number.
Ethics approval and consent to participate
: Ethical approval for the study was granted by the Committee on Research involving Human Subjects, region Arnhem-Nijmegen (CCMO number: NL36793.091.11) and local feasibility and approval was confirmed by the ethical review boards of all participating hospitals. All participants provided written informed consent.
: Not applicable.
: The authors declare that they have no competing interests.