Most sources of error due to confounding and bias are more common in retrospective studies than in prospective studies.
For this reason, retrospective investigations are often criticised.
Case–control studies are often used to identify factors that may contribute to a medical condition by comparing subjects who have that condition/disease (the "cases") with patients who do not have the condition/disease but are otherwise similar (the "controls").
They require fewer resources but provide less evidence for causal inference than a randomized controlled trial.
Increasing the number of controls above the number of cases, up to a ratio of about 4 to 1, may be a cost-effective way to improve the study.
A prospective study watches for outcomes, such as the development of a disease, during the study period and relates this to other factors such as suspected risk or protection factor(s).
The case–control study is frequently contrasted with cohort studies, wherein exposed and unexposed subjects are observed until they develop an outcome of interest.
Controls can carry the same disease as the experimental group, but of another grade/severity, therefore being different from the outcome of interest.
The study usually involves taking a cohort of subjects and watching them over a long period.
The outcome of interest should be common; otherwise, the number of outcomes observed will be too small to be statistically meaningful (indistinguishable from those that may have arisen by chance).
Comments Matched Case Control Study
Case–control study - Wikipedia
A case–control study is a type of observational study in which two existing groups differing in outcome are identified and compared on the basis of some.…
Why matching? - FEM Wiki
This process is called matching. Matching is most often applied in to case controls studies, however matching may be performed also in cohort studies 1.…
A matched case-control study to assess the association between.
We conducted a matched population-based case-control study using linked administrative healthcare data in Ontario, Canada to assess the.…
Statistical Analysis of Individually Matched Case-Control Studies in.
Statistical analysis of individually matched case-control studies in epidemiology factor under study a discrete variable taking multiple values. M. C. PIKE* and J.…
A retrospective, matched case–control study - Nature
This is a retrospective, paired case–control study in which 121 children with ED case group and 121 children without ED control group were.…
Design and Analysis of Case-Control Studies - UC Davis Health
Control studies. ▫ Understand key considerations in designing a case-control study, such as confounding and matching. ▫ How to determine.…
The use and misuse of matching in case-control studies the.
Matching control selection strategies are often used in polycystic ovary syndrome case-control studies; however, they are infrequently used in an appropriate.…
Matched case-control studies - Cambridge University Press
The individual matching of controls to cases in a case-control study may be used to control for confounding or background variables at the.…
Case Control - Study Design 101 - Himmelfarb Library
Case control studies are observational because no intervention is attempted and. Does the study use matching or pairing appropriately to avoid the effects of a.…
Case-Control Study Definition, Real Life Examples - Statistics How To
Non-matched case-control study this is the simplest form. Find a person with the disease and enroll them in the study. Then enroll a control and.…