National, regional, and global trends in body-mass index since 1980: systematic analysis of health examination surveys and epidemiological studies with 960 country-years and 9.1 million participants - Finucane, M M; Stevens, G A; Cowan, M J; Danaei, G; Lin, J K; Paciorek, C J; Singh, G M; Gutierrez, H R; Lu, Y; Bahalim, A N; Farzadfar, F; Riley, L M; Ezzati, M (Lancet, 2011)