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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.
Correlational Study Correlational research studies are one common type of scientific research. It is important to have a good understanding of correlational research.orrelational Study Correlational research studies are one common type of scientific research. It is important to have a good understanding of correlational research.