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What is Severe mental retardation means IQ in the range of and explain in detail?
ICD-10 Codes for Mental Retardation F70 Mild mental retardation IQ 50-69 F71 Moderate mental retardation IQ 35-49 F72 Severe mental retardation IQ 20-34 F73 Profound mental retardation IQ <20 Reference: Page No .3450 chap. 37 Intellectual Disability (Kaplan & Sadock's Comprehensive Textbook of Psychiatry, 9th Edition)