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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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Direction of case control study
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The correct answer is  Case-control study has 3 distinct features: Both exposure and outcome have occurred before the sta of the study The study proceeds backward from effect to cause It uses a control or comparison group to suppo or refute an inference Ref: 25th edition, Park's Textbook of Preventive and Social Medicine, Page no. 79