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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.
user
The type of study that determines the norms and limits of the distribution of variables, including the characteristics of the events and population under study, is reffered to as-
assistant
The correct answer is  Descriptive studies are the first phase of an epidemiological investigation. Procedures in descriptive studies include: 1)defining the population to be studied 2)defining the disease under study 3)describing the study by time , place, person 4)measurement of disease 5)comparing with known indices 6)formulation of an aetiological hypothesis (refer pgno:63 park 23 rd Edition)