%0 Journal Article %A J A Kopec %A J M Esdaile %T Bias in case-control studies. A review. %D 1990 %R 10.1136/jech.44.3.179 %J Journal of Epidemiology and Community Health %P 179-186 %V 44 %N 3 %U https://jech.bmj.com/content/jech/44/3/179.full.pdf