Using the strengths and difficulties questionnaire with adults with Down syndrome

The Strengths and Difficulties Questionnaire (SDQ) has been widely used to screen typically developing children for mental health problems; in recent years it has also been used with children with intellectual disabilities. The present study investigated the possible use of the SDQ to screen adults with Down syndrome (DS).

Only four items on the SDQ were changed slightly to remove references to children. Parents or carers completed the SDQ and all 125 adults with DS (aged 18-43 years) were assessed for mental health problems by a psychiatrist.

Twenty-eight adults were diagnosed with a psychiatric condition. Parents and carers found the SDQ easy to complete and liked the inclusion of positive behaviours. The SDQ did discriminate significantly between those with and without a diagnosis, however the sensitivity and specificity were insufficient. Exploratory and Confirmatory Factor Analyses showed a four factor model (pro-social behaviour, emotional difficulties, hyperactivity and conduct disorders) to be the best solution. This structure was similar to previous research findings of three factors of pro-social behaviour, internalising disorders and externalising disorders.

Construct validity and reliability suggest that the SDQ has potential for use with adults with DS and possibly those with other intellectual disabilities. The SDQ is user friendly for parents and carers, and did highlight behavioural and mental health needs, suggesting that it would be worthwhile to develop the SDQ specifically for adults with intellectual disability.