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Cohort study

If we not able to randomly assign people,  we have the following type of study called a cohort study. A defined population not randomly assigned with self selected or assigned by other people to exposure to non-exposure. People for example may work at certain industrial plan. Others seek job at another plan. And then we follow-up people who have the exposure and people who don’t have the exposure and look at the rate of the disease at both groups. If indeed the exposure is related to the disease we would expect to see a greater number of people with the disease in the exposure group than the non-expose group.


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