1. School of Clinical Medicine, University of Cambridge; Primary Care Unit, Department of Public Health and Primary Care; Strangeways Research Laboratory, 2 Worts’ Causeway Cambridge UK CB1 8RN
2. School of Public Health, Peking University; Centre for Evidence Based Medicine and Clinical Research, Department of Epidemiology and Biostatistics; Beijing China 100191
3. McMaster University; Department of Health Research Methods, Evidence, and Impact; 1280 Main Street West Hamilton ON Canada L8S 4K1
4. Catholic University of Croatia; Department of Nursing; Ilica 242 Zagreb Croatia 10000
5. General Hospital "Dr. Ivo Pedišić"; Department for Dermatology and Venereology; J.J. Strossmayera 59 Sisak Croatia 44000
6. Peking University First Hospital; Department of Dermatology and Venereology; 8 Xishiku Main Street Beijing Xicheng District China 100034
7. Beijing Key Laboratory of Molecular Diagnosis on Dermatoses; Beijing China
8. National Clinical Research Center for Skin and Immune Diseases; Beijing China
9. Yale School of Public Health; Department of Chronic Disease Epidemiology; 367 Cedar ST RM 704 New Haven Connecticut USA 06510
10. Xuanwu Hospital, Capital Medical University; Department of Neurology; Changchun Street 45 Beijing China 100053
11. The University of Nottingham; c/o Cochrane Skin Group; A103, King's Meadow Campus Lenton Lane Nottingham UK NG7 2NR