Psychiatric disturbances in children with intellectual disability : Prevalence, risk factors and assessment

Children with intellectual disability are at increased risk for emotional and behavioural problems, but many of these disturbances fail to be diagnosed. Structured checklists have been used to supplement the psychiatric assessment of children without intellectual disability, but for children with intellectual disability, only a few checklists are available. The aim of the study was to investigate psychiatric disturbances among children with intellectual disability: the prevalence, types and risk factors of psychiatric disturbances as well as the applicability of the Finnish translations of the Developmental Behaviour Checklist (DBC-P) and the Child Behavior Checklist (CBCL) in the assessment of psychopathology. The subjects comprised 155 children with intellectual disability, and data were obtained from case records and five questionnaires completed by the parents or other carers of the child. According to case records, a psychiatric disorder had previously been diagnosed in 11% of the children. Upon careful re-examination of case records, the total proportion of children with a psychiatric disorder increased to 33%. According to checklists, the frequency of probable psychiatric disorder was 34% by the DBC-P, and 43% by the CBCL. The most common diagnoses were pervasive developmental disorders and hyperkinetic disorders. The results support previous findings that compared with children without intellectual disability, the risk of psychiatric disturbances is 2-3-fold in children with intellectual disability. The risk of psychopathology was most significantly increased by moderate intellectual disability and low socio-economic status, and decreased by adaptive behaviour, language development, and socialisation as well as living with both biological parents. The results of the study suggest that both the DBC-P and the CBCL can be used to discriminate between children with intellectual disability with and without emotional or psychiatric disturbance. The DBC-P is suitable for children with any degree of intellectual disability, and the CBCL is suitable at least for children with mild intellectual disability. Because the problems of children with intellectual disability differ somewhat from those of children without intellectual disability, checklists designed specifically for children with intellectual disability are needed.