IntroductionThe Strengths and Difficulties Questionnaire (SDQ) is a relatively short instrument developed to detect psychosocial problems in children aged 3–16 years. It addresses four dimensions: emotional problems, conduct problems, hyperactivity/inattention problems, peer problems that count up to the total difficulties score, and a fifth dimension; prosocial behaviour. The validity and reliability of the SDQ has not been fully investigated in younger age groups. Therefore, this study assesses the validity and reliability of the parent and teacher versions of the SDQ in children aged 5–6 years in the total sample, and in subgroups according to child gender and parental education level.MethodsThe SDQ was administered as part of the Dutch regularly provided preventive health check for children aged 5–6 years. Parents provided information on 4750 children and teachers on 4516 children.ResultsFactor analyses of the parent and teacher SDQ confirmed that the original five scales were present (parent RMSEA = 0.05; teacher RMSEA = 0.07). Interrater correlations between parents and teachers were small (ICCs of 0.21–0.44) but comparable to what is generally found for psychosocial problem assessments in children. These correlations were larger for males than for females. Cronbach’s alphas for the total difficulties score were 0.77 for the parent SDQ and 0.81 for the teacher SDQ. Four of the subscales on the parent SDQ and two of the subscales on the teacher SDQ had an alpha <0.70. Alphas were generally higher for male children and for low parental education level.DiscussionThe validity and reliability of the total difficulties score of the parent and teacher SDQ are satisfactory in all groups by informant, child gender, and parental education level. Our results support the use of the SDQ in younger age groups. However, some subscales are less reliable and we recommend only to use the total difficulties score for screening purposes.

The total difficulties score of the parent- and teacher-rated SDQ is valid and reliable for different ethnic groups within Dutch society. However, there are differences in reliability and validity of the subscales, which makes interpretation of the subscales difficult for certain ethnic groups.

Child health professionals should be aware of ethnic variations in problem perception as low problem perception in parents of non-Dutch children may lead to miscommunication and unmet need for professional care for the child.