1. Division of Rheumatology, Allergy and Immunology, Chang Gung Memorial Hospital, Taoyuan, Taiwan
2. Department of Internal Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan
3. Biostatistics Core Laboratory, Molecular Medicine Research Centre, Taoyuan, Taiwan
4. Department of Public Health, College of Medicine, Chang Gung University, Taoyuan, Taiwan
5. Division of Rheumatology, Orthopaedics and Dermatology, School of Medicine, University of Nottingham, Nottingham, UK