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Slide Presentation from the AHRQ 2007 Annual Conference

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Case-Control Study Design

Text Description is below the image.

Flowchart showing "Case-Control Study Design." The chart begins on the right with the heading "Begin." The heading on the left is "Classify/Compare." Under "Begin" there is an arrow pointing to two text boxes: one saying Cases (ADE), and the other one Controls. The Cases (ADE) box has an arrow pointing left to the Classify/Compare column to a text box labeled "Drug Exposure: Yes or No?." The Controls text box has an arrow pointing to an identical text box directly under the first text box.


We use Medicaid data to perform observational studies. We employ traditional epidemiologic methods—primarily case-control and cohort study designs. This figure describes the case-control study design. In this type of study, we actually begin at the end with people who have experienced a particular outcome of interest—these are the cases. In our studies, cases are defined by the use of a drug that we believe to be a proxy or marker for an adverse drug reaction or ADR. We also identify controls who are not receiving this particular drug treatment. Then we search back into the past of the cases and controls for another drug exposure that might be related to the adverse drug reaction.

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