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What is Most common type of mental retardation - and explain in detail?
The number of mild cases far exceed the severe and profound cases English statistics suggest that among 100 mentally handicaped persons 70 mild, 20 moderate, 5 severe cases WHO classification of Mental retardation(MR) mild MR...IQ 50-70 moderate MR ...35-49 severe MR..IQ 20-34 profound MR...IQ under 20 ref; (page no;582) 23rd edition of PARK&;s textbook of Preventive and Social medicine