Question

what is case-controlled studies. and examples

Answer 1

Ans. Case controlled studies - a case controlled studies is a retrospective study that looks back in time to find the relative risk between a specific exposure ( e.g.second hand tobacco smoker) and an outcome ( e.g. cancer) .

A control group of people who did not have the disease or who did not experience the event is used for comparison

The case control is a type of epidemiological observational study.

An observational study is a study in which subjects are not randomized to the exposed or unexposed group rather the subjects are observed in order to determine both their exposure and their outcome status and the exposure status in thus not determined by the researchers

Example

This study for non-Hodgkin lymphoma found a connection between the disease and inflammatory disorder like sjogrens,celiac and rheumatoid arthritis.

This study investigated how increased consuption of fruits and vegetables protects against cervical intraepithelial neoplasia .