Screening for psychiatric disorders in a total population of adults with intellectual disability and challenging behaviour using the PAS-ADD checklist.

Background Previous research has suggested a variety of possible relationships between the presence of symptoms of psychiatric disorder and challenging behaviours in people with intellectual disability. This study explores this relationship in a total population sample of adults with challenging behaviour. Materials and Methods Over 800 service settings in a defined geographical area were screened to identify individuals with challenging behaviour. Detailed behavioural data, Psychiatric Assessment Schedule for Adults with a Developmental Disability (PAS-ADD) checklist and Adaptive Behaviour Scale (Part 1) scores were collected on 76% of the 930 adults identified. Results Just under 17% of participants reached threshold scores on one on more subscales of the PAS-ADD checklist. There was some evidence of increasing behavioural severity being associated with increasing psychiatric symptoms. There were no associations between specific forms of challenging behaviour and individual symptoms. Conclusions The data would appear supportive of previous suggestions that it is unlikely that the majority of challenging behaviours in adults with intellectual disability are underpinned by psychiatric disorder.