[1] Univ Nottingham, Queens Med Ctr, Ctr Evidence Based Dermatol, Univ Hosp NHS Trust, Nottingham NG7 2YH, England
[2] Univ Auckland, Sch Populat Hlth, Auckland, New Zealand
[3] Univ Childrens Hosp, Munich, Germany
[4] Natl Heart & Lung Inst, London, England
[5] Univ London, Div Community Hlth Sci, London, England