Webster, J; Chandramohan, D; Freeman, T; Greenwood, B; Kamawal, AU; Rahim, F; Rowland, M; (2003) A health facility based case-control study of effectiveness of insecticide treated nets: potential for selection bias due to pre-treatment with chloroquine. Tropical medicine & international health, 8 (3). pp. 196-201. ISSN 1360-2276 DOI: https://doi.org/10.1046/j.1365-3156.2003.01013.x Full text not available from this repository.