What type of study follows two groups from their inception for many years to observe the effects of exposure?

A cohort study is designed to follow two groups over an extended period to observe how different exposures affect outcomes. In this type of study, researchers identify a population or cohort and classify individuals based on their exposure status. For example, one group may be exposed to a certain risk factor, while the other group is not. By tracking these groups over time, researchers can gather data on the incidence or prevalence of specific health outcomes, allowing them to analyze the relationship between the exposure and the outcome of interest.

The longitudinal nature of cohort studies is crucial, as it enables the observation of temporal relationships and the development of disease or other outcomes, providing insights into cause-and-effect relationships. This makes cohort studies particularly valuable for identifying risk factors and understanding the natural progression of diseases within populations over time.