Statistics notes: Matching
- 29 October 1994
- Vol. 309 (6962) , 1128
- https://doi.org/10.1136/bmj.309.6962.1128
Abstract
This is the ninth in a series of occasional notes on medical statistics In many medical studies a group of cases, people with a disease under investigation, are compared with a group of controls, people who do not have the disease but who are thought to be comparable in other respects. This happens in epidemiological case-control studies, where a possible risk factor is compared between cases and controls to investigate the nature of the disease. In both types of study cases and controls are sometimes matches. This means that for every case there is a control who has the same (or closely similar) values of the matching variables. Matching may be by sex, age to within five years, ethnic group, etc. Sometimes there are two or more such controls for each case. We match to ensure that controls and cases …This publication has 0 references indexed in Scilit: