The Framingham hea study is an example of-
Coho study is also known as incidence study. The cohos are identified prior to the appearance of disease under investigation. The study group so defined are observed over a period of time to determine the frequency of disease among them. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 83
Case-control study
Coho study
Randomized controlled trial
Cross-sectional study
Epidemiology