1. Department of Epidemiology of Microbial Disease, Yale School of Public Health, 60 College Street, New Haven, CT 06520, USA
2. Yale University School of Medicine, 333 Cedar St, New Haven, CT 06510, USA
3. Johns Hopkins Hospital, 600 N. Wolfe St., Harvey 808, Baltimore, MD 21287, USA
4. Faculty of Nursing and Public Health, Khesar Gyalpo University of Medicine and Health Sciences, Thimphu, Bhutan
5. Bhutan Cancer Society, PO Box 169, Changlam House No. 8, Thimphu, Bhutan