[1] Univ Queensland, Sch Publ Hlth, Fac Med, Brisbane, Qld 4006, Australia
[2] Clin Res Educ Networking & Consultancy, Noncommunicable Dis Unit, Douala, Cameroon
[3] Univ Libre Bruxelles, Fac Med, Brussels, Belgium
[4] Bamendjou Dist Hosp, Bamendjou, Cameroon
[5] Etoug Ebe Baptist Hosp Yaounde EBHY, Yaounde, Cameroon
[6] Univ Liverpool Liverpool Sch Trop Med, Dept Int Publ Hlth, Pembroke Pl, Liverpool L3 5QA, Merseyside, England
[7] Hlth & Human Dev Res Grp 2HD, Douala, Cameroon
[8] Univ Buea, Fac Hlth Sci, Buea, Cameroon
[9] London Sch Hyg & Trop Med, Fac Infect & Trop Dis, Dept Clin Res, London, England