The Strengths and Difficulties Questionnaire [SDQ; (1)] is a multi-informant instrument for screening developmental psychopathology. This study contributes to the validation of the Italian SDQ-Parent version (SDQ-P), analyzing its factorial structure, providing norms and investigating cross-informant agreement (parents-teachers). The SDQ-P and the SDQ-Teacher version (SDQ-T) were completed for 1917 primary and middle school students. Confirmatory factor analyses were performed to compare two factorial structures: the original five-factor model and the structure obtained in a past Italian study (2). The original model showed the best fit. Significant differences by gender and school grade were found; norms were provided separately for males and females attending 1st-2nd, 3rd-5th and 6th-8th grades. Finally, the analysis of parent-teacher agreement showed correlations ranging from small (prosocial behavior) to large (hyperactivity-inattention). This study offers some reflections on the best way to use this instrument in a community sample.
Keywords: Cross-informant agreement; Italian norms; Parents; Psychometric properties; Strengths and Difficulties Questionnaire.