Factor Structure of the Self-Report Strength and Difficulties Questionnaire in a Diverse U.S. Sample

The Strengths and Difficulties Questionnaire (SDQ) is a widely used mental health screening instrument developed in the United Kingdom that measures five proposed factors. U.S. research, however, historically supports a slightly different three-factor solution. The present study reports results using both principal factor analysis (PFA) and confirmatory factor analysis (CFA) on data from multiple waves of an ongoing mental health project in middle school aged children. PFA analyses suggested three, five and six-factor solutions with substantial cross-loadings from items. CFAs showed alternative five and six-factor solutions fit well when items guided by the initial PFA were allowed to cross-load. Neither the original five-factor nor popular three-factor models fit well without allowing cross-loading items. These data suggest that popular SDQ three and five-factor model may have variable fit in certain U.S. populations.