The researchers compare the 2 groups to see if any exposure (such as alcohol use) was more common in the history of one group compared to the other. Controls are people who do not have the outcome.Cases are people who already have an outcome (such as breast cancer).In a case-control study, researchers identify 2 groups: cases and controls. Researchers compare the different groups (for example, they might compare heavy drinkers, moderate drinkers, light drinkers and non-drinkers) to see which group is more likely to develop an outcome (such as breast cancer). Some people will have a certain exposure (such as alcohol use) and others will not. There are 2 types of observational studies:Ī prospective cohort study follows a large group of people forward in time. They report these activities to researchers. They exercise when they want, eat what they like and take the medicines their doctors prescribe.

In observational studies, the people in the study live their daily lives as they choose. The strengths of the conclusions they reach.Though they have the same goal, observational studies and randomized controlled trials differ in:

Observational studies ( prospective cohort or case-control).

The 2 main types of epidemiology studies are:

The goal of epidemiology studies is to give information that helps support or disprove an idea about a possible link between an exposure (such as alcohol use) and an outcome (such as breast cancer) in people. Types of Research Studies Epidemiology studiesĮpidemiology is the study of the patterns and causes of disease in people.

Another word for previous studied