Cohort study

A cohort study or panel study is a quasi-experiment in the form of a longitudinal study (generally a type of observational study) used in medicine, nursing, psychology, social science, actuarial science, business analytics, and ecology. In a cohort study there is a passive follow-up of a group of people and a documentation of relevant characteristics or events related to this group of people. For instance in medicine, it is an analysis of risk factors and follows a group of people who do not have the disease, and uses correlations to determine the absolute risk of subject contraction. It is one type of clinical study design and should be compared with a cross-sectional study. Cohort studies are largely about the life histories of segments of populations, and the individual people who constitute these segments.