You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Case - control study is a type of - and explain in detail?
. case control studies are generally called "retrospective studies"are used to test casual hypothesis.they are basically comparison studies.cases and controls must be compared with respect to known "confounding factors"other kind of analytical studies include coho study. ref;park&;s textbook of preventive and social medicine,22 nd edition,pg no 66