Childhood pneumonia and crowding, bed-sharing and nutrition: a case-control study from The Gambia - Howie, SR; Schellenberg, J; Chimah, O; Ideh, RC; Ebruke, BE; Oluwalana, C; Mackenzie, G; Jallow, M; Njie, M; Donkor, S; Dionisio, KL; Goldberg, G; et al. (International Journal of Tuberculosis and Lung Disease, 2016)