The Strengths and Difficulties Questionnaire (SDQ) is one of the most broadly used questionnaires to evaluate children's psychological adjustment, however its internal structure has been a target of ongoing controversy. Recent studies suggested a three-factor structure of the SDQ, however data is still scarce. The present study used the Multitrait-Multimethod analysis to examine SDQ construct related-validity with three and five dimensions, provided by children, their parents and teachers. A total of 415 participants were recruited from a Portuguese community sample. Both SDQ versions presented good convergence-related validity, with higher values for the five version. Findings from this study suggest that the SDQ with three dimensions could be more suitable as a screening measure of children's psychological adjustment in a community low-risk sample. Nevertheless, the SDQ still needs further psychometric improvements in order to properly collect information from multi-source samples about the prevalence of children's psychological adjustment.
Keywords: Strengths and difficulties questionnaire; convergent-related validity; discriminant-related validity; multi-informants; multitrait-multimethod.