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The answer to this is misleading. Unlike in cohort or experimental studies, matching in a case-control study does not of itself reduce confounding (paradoxically, it can introduce confounding where none was present). It can, however, make statistical adjustment for a suspected confounder more efficient [1]
1.Rothman KJ. Chapter 13, Matching. In: Rothman KJ. Modern Epidemiology. Little Brown and Company: Boston, 1986, p237-246.
Competing interests:
No competing interests
16 February 2012
David Coggon
Professor of occupational and Environemntal Medicine
Keith Palmer
MRC Lifecourse Epidemiology Unit, University of Southampton
MRC Lifecoursse Epidemiology Unit, Southampton General Hospital, Southampton SO16 6YD
Re: Why match in case-control studies?
The answer to this is misleading. Unlike in cohort or experimental studies, matching in a case-control study does not of itself reduce confounding (paradoxically, it can introduce confounding where none was present). It can, however, make statistical adjustment for a suspected confounder more efficient [1]
1.Rothman KJ. Chapter 13, Matching. In: Rothman KJ. Modern Epidemiology. Little Brown and Company: Boston, 1986, p237-246.
Competing interests: No competing interests