Clinical assessment. Many child and adolescent mental health clinics now use the SDQ as part of the initial assessment, getting parents, teachers and young people over the age of 11 to complete questionnaires prior to the first clinical assessment. The findings can then influence how the assessment is carried out and which professionals are involved in that assessment. For example, if a child has been referred with marked conduct problems, an assessment that focused too narrowly on these behaviors and related family issues might overlook associated hyperactivity. Advance knowledge that the child has been given high SDQ hyperactivity ratings by parents and teachers can help ensure that the assessment inquires in detail about hyperactivity; it may also be important to obtain a psychiatric or pediatric opinion early on in the assessment process with a view to establishing suitability for medication (Goodman, Renfrew, & Mullick, 2000).
Evaluating outcome. “Before” and “after” SDQs can be used to audit everyday practice (e.g. in clinics or special schools) and to evaluate specific interventions (e.g. parenting groups). Studies using the SDQ along with research interviews and clinical ratings have shown that the SDQ is sensitive to treatment effects. Child and adolescent mental health services, and other specialist services for children with emotional and behavioral difficulties, can use an ‘added value’ score based on the SDQ as one index of how much help they are providing to the young people they see.
Epidemiology. The SDQ’s emphasis on strengths as well as difficulties makes it particularly acceptable to community samples (Goodman & Scott, 1999). It has been widely used in large epidemiological studies. The SDQ is well adapted for studies of the general population since it is a dimensional measure across its full range, with each one-point increase corresponding to an increased rate of disorder (Goodman & Goodman, 2009). In addition, the same risk factors that predict change in total difficulty score across the entire range also predict it in children one standard deviation above and one standard deviation below the mean (Collishaw, Meltzer, & Goodman, 2007). In Britain, mean SDQ scores can be used to generate prevalence estimates in sub-populations defined by a wide range of characteristics (e.g. ethnicity, family type, socioeconomic deprivation) (Goodman & Goodman, 2011). Note, however, that these prevalence estimators cannot be used to generate valid prevalence estimators cross-nationally (Goodman et. al., 2011).
Research. The SDQ is being used as a research tool throughout the world in over 4000 studies. These include developmental, genetic, social, clinical and educational studies.
Screening. In community samples, multi-informant SDQs can predict the presence of a psychiatric disorder with good specificity and moderate sensitivity (Goodman et. al., 2000) (Goodman, Renfrew, & Mullick, 2000).