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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Of the different epidemiological study designs available to test the association between risk factor and disease, the best design is of
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The correct answer is  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