[1] Univ Nottingham, Nottingham, England
[2] Univ Bristol, Populat Hlth Sci, Bristol Med Sch, Bristol, England
[3] Keele Univ, Res Inst Primary Care & Hlth Sci, Keele, Staffs, England
[4] Chang Gung Mem Hosp, Div Rheumatol Allergy & Immunol, Taoyuan 333, Taiwan
[5] Univ Nottingham, Sch Med, Div Primary Care, Nottingham, England
[6] Univ Nottingham, Div Rheumatol Orthopaed & Dermatol, Acad Rheumatol, Nottingham, England