Funding for this research was provided by:
Received: 15 October 2018
Accepted: 7 January 2019
First Online: 18 January 2019
Ethics approval and consent to participate
: This study was conducted with the approval of the regional ethics committee at Leiden University Medical Center. The IMPROVED study was approved by the Medical Ethics Committees of all participating hospitals. Informed consent was obtained from all participants.
: Not applicable.
: R.E.M.T., T.W.J.H., and L.A.T. are among the inventors of a patent on the use of carbamylated antigens for diagnosis. H.B. is an employee of Orgentec Diagnostika, which manufactures diagnostic anti-acetylated peptide antibody assays. All other authors declare that they have no competing interests.
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