Funding for this research was provided by:
Soonchunhyang University (NA)
Ministry of National Research Foundation of Korea (2018R1C1B5045586)
Korean College of Rheumatology (NA)
Received: 3 April 2019
Accepted: 21 August 2019
First Online: 11 September 2019
Ethics approval and consent to participate
: This study was approved by the ethics committee of all institutions involved including Institutional Review Board (IRB) of Soonchunhyang University Cheonan Hospital (IRB number: 2015–12-012). Informed consent was obtained by each involved institution. Informed written consent from patients was obtained by each involved institution. The full names of ethics committees of the participating institutions are provided by Additional file InternalRef removed.
: Not applicable
: The authors declare that they have no competing interests.