The Strengths and Difficulties Questionnaire: the factor structure in a sample of Korean immigrant parents in New Zealand

OBJECTIVE: The Strengths and Difficulties Questionnaire (SDQ) is a widely used, brief, 25-item instrument for screening for adaptive and problematic behaviour in children and adolescents. Despite its widespread application in child and adolescent research, concerns regarding the construct validity of the instrument have been expressed. Further, to date, limited research has been conducted using Korean and Korean immigrant samples to provide data about the reliability and validity of the SDQ and the factorial structure of this instrument. The purpose of this study was to examine the construct validity, based on pre-existing models suggested by the extant literature, for the parent-informant version of the questionnaire.

METHODS: A sample of 207 Korean immigrant parents in New Zealand completed the SDQ for their children (ages 6 and 10). The resulting data were subjected to confirmatory factor analysis (CFA), testing four competing models: a three-factor model (internalization dimension, externalization dimension, and a prosocial factor), a five-factor model (emotional symptoms, peer problems, conduct problems, hyperactivity, and prosocial), a six-factor model (a separated uncorrelated method factor, four symptom factors, and the single prosocial factor), and a hierarchical model in which the four first-order problem-oriented scales form a higher order difficulties factor.

RESULTS: CFA of the SDQ partially supported the traditional five-factor conceptualization of the SDQ, although some modifications were necessary to reach an acceptable fit. Reliability was a concern particularly for Emotional Symptoms and Peer Problems.

CONCLUSIONS: The use of the revised five-factor model of the SDQ in the present setting should be interpreted with caution. Some items need to be further evaluated and revised to capture the originally intended constructs.