[1] Univ Tampere, Sch Med, Dept Int Hlth, FIN-33101 Tampere, Finland
[2] Duke Natl Univ Singapore, Grad Sch Med, Ctr Quantitat Med, Singapore, Singapore
[3] Singapore Clin Res Inst, Dept Biostat, Singapore, Singapore
[4] Univ Calif Davis, Dept Nutr, Davis, CA 95616 USA
[5] Univ Malawi, Coll Med, Dept Community Hlth, Blantyre, Malawi
[6] Univ Calif Davis, Dept Agr & Resource Econ, Davis, CA 95616 USA
[7] Tampere Univ Hosp, Dept Paediat, Tampere, Finland