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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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The screening strategy for prevention of blindness from diabetic retinopathy according to the NPCB involves-
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The correct answer is  Ref: Parks 23rd edition pg 137 Screening will be most productive if applied selectively to high-risk groups, the groups defined on the basis of epidemiological research.