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What is Migration study is used to study: and explain in detail?
MIGRATION STUDIES Use: Evaluation of role of possible Genetic and Environmental factors in occurence of a disease in a population. Study Design: Comparision of Disease rates & Death rates of, Migrants with kin who stayed at home. MIgrants with Local population of host country. Limitation: Non-random assignment to Groups: Migrants are self-selected Environmental factors may act at ceain age/point only Not useful for disease with long incubation period Ref: Park 25th edition Pgno: 75