A 12-year-old child who is having difficulty in school is given an intelligence test. The test determines that the child is functioning mentally at the level of an 8-year-old child. What category of intellectual function best describes this child?

Using the IQ formula, IQ = MA/CA x 100, the IQ of this child is 8 years (mental age)/12 years (chronological age) x 100, that is, about 66 (IQ). An individual with an IQ of 66 is classified with mild mental retardation (IQ 50-70). ICD 10 LEVEL IQ ICD 10 code Mild (Educable) 50-70 F70 Moderate (Trainable) 35-49 F71 Severe (Dependent) 20-34 F72 Profoun <20 F73 Severity unspecified Untestable by standard tests F78