====== Retrospective Controlled Cohort Study ======

A Retrospective Controlled Cohort Study is a type of [[observational study]] in which researchers look back in time (using existing data) to compare outcomes between two or more predefined groups (cohorts) based on their exposure or treatment status.

Key Features:

[[Retrospective study]]: The study uses past records or data (e.g., medical charts, registries) to identify both exposures and outcomes.

[[Controlled study]]: There is a comparison group—often a control cohort that did not receive the intervention or exposure of interest.

[[Cohort study]]: Participants are grouped based on a shared characteristic or exposure, such as having received a particular treatment.

Temporal relationship: The exposure precedes the outcome, but both have already occurred at the time of study initiation.