Validity of the Strengths and Difficulties Questionnaire in Preschool-Aged Children

BACKGROUND: The Strengths and Difficulties Questionnaire (SDQ) is widely used to screen for child mental health problems and measure common forms of psychopathology in 4- to 16-year-olds. Using longitudinal data, we examined the validity of a version adapted for 3- to 4-year-olds. METHODS: We used SDQ data from 16 659 families collected by the Millennium Cohort Study, which charts the development of children born throughout the United Kingdom during 2000–2001. Parents completed the preschool SDQ when children were aged 3 and the standard SDQ at ages 5 and 7. The SDQ’s internal factor structure was assessed by using confirmatory factor analysis, with a series of competing models and extensions used to determine construct, convergent, and discriminant validity and measurement invariance over time. Predictive validity was evaluated by examining the relationships of age 3 SDQ scores with age 5 diagnostic measures of attention-deficit/hyperactivity disorder, autism spectrum disorder/Asperger syndrome, and teacher-reported measures of personal, social, and emotional development. RESULTS: Confirmatory factor analysis supported a 5-factor measurement model. Internal reliability of subscales ranged from ω = 0.66 (peer problems) to ω = 0.83 (hyperactivity). Item-factor structures revealed measurement invariance over time. Strong positive correlations between ages 3 and 5 SDQ scores were not significantly different from correlations between age 5 and 7 scores. Conduct problems and hyperactivity subscales independently predicted developmental and clinical outcomes 2 years later. CONCLUSIONS: Satisfactory psychometric properties of the adapted preschool version affirm its utility as a screening tool to identify 3- to 4-year-olds with emotional and behavioral difficulties.