Casecontrol
Case-control study, also known as case-control design, is an observational study used to identify factors associated with a particular outcome, most commonly a disease. It starts with people who already have the outcome (cases) and compares them with people who do not (controls) to examine prior exposure history. The aim is to determine whether exposure is more common among cases, suggesting a possible association.
Selection: Cases are individuals with the disease or outcome of interest; controls are chosen from the same
Analysis: The primary measure is the odds ratio, estimating how the odds of exposure differ between cases
Limitations: Susceptible to biases, notably recall bias and selection bias in control selection. Confounding can distort
Variants: Nested case-control studies within a cohort, population-based or hospital-based designs, matched or unmatched. Nested designs