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What is Which one of the following is a coho study and explain in detail?
A coho study is a paicular form of a longitudinal study that samples a coho (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as bih or graduation), performing a cross-section at intervals through time. Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 83