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Cohort Study is an observational study in which a group of individuals â a cohort â are followed over a period of time in order to determine either the incidence rate of certain diseases or the risk factors that lead to those diseases. These studies can be either prospective or retrospective.
What researchers mean by... cohort studies, case control studies and randomized controlled trials. When people read about a research study, they may not pay attention to how the study was designed. But to understand the quality of the findings, itâs important to know a bit about study design. According to the widely-accepted hierarchy of evidence, the most reliable evidence comes from systematic reviews, followed by evidence from randomized controlled trials, cohort studies and then case control studies.