Case-control studies are a commonly used to study rare diseases with long latency periods, and matching cases and controls individually is an often used method to control for the effects of potential confounding variables. The analysis of such matched data, however, requires special statistical methods.
Niven et al. (1) wished to investigate how many of published, peer-reviewed matched case-control studies that were analysed using appropriate statistical methodology. They identified and reviewed 37 matched case-control studies. Of these, 16 (43%), were adequately analysed. Studies with adequate analysis had more often than other studies cases with cancer and heart disease, 10/16 (63%) versus 5/21 (24%) and more often multiple controls , 14/16 (88%) versus 13/21 (62%). They were also more often published in a high impact journal.
The authors conclude that it their study raises concern that a majority of matched case-control studies present findings that are based on inadequate statistical analyses.
- Niven DJ, Berthiaume LR, Fick GH, Laupland KB. Matched case-control studies: a review
of reported statistical methodology. Clinical Epidemiology 2012:4;99–110.