Historical Cohort Study

A historical cohort study is a research method that looks back at existing records to compare groups based on past exposures or experiences. Researchers identify a group of people who were exposed to a certain factor (like a chemical or behavior) and a comparable group who were not. They then follow both groups' records over time to see how many develop a specific outcome, such as a disease. This approach helps scientists understand potential causes of health conditions by analyzing data already collected, making it a cost-effective way to study associations between exposures and outcomes.