[1] Univ Cape Town, Dept Publ Hlth & Primary Hlth Care, Hlth Econ Unit, Fac Hlth Sci,Observatory, ZA-7925 Cape Town, South Africa
[2] Univ Witwatersrand, Ctr Hlth Policy, Johannesburg, South Africa
[3] London Sch Hyg & Trop Med, Hlth Econ & Financing Programme, London WC1, England