A broad spectrum of disorders with childhood onset, characterized by impairment or delay in functions related
to central nervous system maturation, and with a steady course rather than remissions and relapses as in other
mental illnesses. They include intellectual disability/mental retardation as well as pervasive developmental disorders
such as autism.


  • May not be known
  • Nutritional deficiencies e.g iodine deficiencies
  • Medical conditions
  • Alcohol use during pregnancy
  • Risk factors: maternal depression, infections in pregnancy

Clinical features

  • Delay in development (using local developmental
    milestones or comparison with other children)

Intellectual disability

  • Impairment of skills across multiple development areas (i.e. cognitive, language, motor and skills)
  • Lower intellingence and decreased ability to adapt to daily demands of life

Pervasive developmental disorders including autism

  • Impaired social behaviour, communication and language
  • Oddities in communication (lack of social use of language skills, lack of flexibility of language used)
  • Loss of previously acquired skills
  • Narrow range of interests and activities that are both unique to the individual and carried out repetitively
  • Originating in infancy or early childhood
  • Some degree of intellectual disability may be present


  • Look for other priority mental, neurological or substance use disorder (depression, epilepsy, behavioural disorder)
  • Consider if delay in development could be due to non stimulating environment or maternal depression
  • Assess for nutritional and other medical conditions e.g. sensory impairments (blindness, deafness etc.)


  • Address medical issues including visual and hearing impairment, nutritional problems
  • Family psychoeducation
  • Parent skills training
  • Contact teachers, advise and plan for special needs education
  • Provide support to carers/family
  • Link with community based rehabilitation services if available
  • Protect and promote human rights of the child: THESE CHILDREN ARE VERY VULNERABLE
  • Refer to specialist for more comprehensive assessment and management