Disorders of intellectual development

Definition

Disorders of intellectual development are a group of etiologically diverse conditions originating during the developmental period characterised by significantly below average intellectual functioning and adaptive behaviour that are approximately two or more standard deviations below the mean (approximately less than the 2.3rd percentile), based on appropriately normed, individually administered standardized tests. Where appropriately normed and standardized tests are not available, diagnosis of disorders of intellectual development requires greater reliance on clinical judgment based on appropriate assessment of comparable behavioural indicators.

Coding note

Use additional code, if desired, to identify any known aetiology.

Exclusions

• Dementia

6 subordinate codes

• 6A00.0Disorder of intellectual development, mild
• 6A00.1Disorder of intellectual development, moderate
• 6A00.2Disorder of intellectual development, severe
• 6A00.3Disorder of intellectual development, profound
• 6A00.4Disorder of intellectual development, provisional
• 4B4ZDiseases of the immune system, unspecified

Nearby in Neurodevelopmental disorders

• 6A01Developmental speech or language disorders
• 6A02Autism spectrum disorder
• 6A03Developmental learning disorder
• 6A04Developmental motor coordination disorder
• 6A05Attention deficit hyperactivity disorder
• 6A06Stereotyped movement disorder
• 4B4YOther specified diseases of the immune system
• 4B4ZDiseases of the immune system, unspecified