A systematic review of some reliability and validity issues regarding the Strengths and Difficulties Questionnaire focusing on its use in out-of-home care.

Purpose: A systematic review was conducted to analyze the inter-rater reliability, cross-informant consistency, test-retest reliability, and temporal stability of the Strengths and Difficulties Questionnaire (SDQ), and its ability to discriminate. Method: We searched three databases for articles about the SDQ (parent, teacher, and self-report version), used samples of children up to age 18 and reported inter-rater reliability, cross-informant reliability, test-retest reliability, temporal stability, specificity, sensitivity, positive predictive value (PPV), and negative predictive value (NPV). Results: Focusing on the TDS, inter-rater, and cross-informant reliability showed acceptable values, but respondent types (e.g., mothers and fathers) are not interchangeable. Test-retest reliability and temporal stability were also acceptable, and not excessively high. Specificity and NPV were acceptable but not sensitivity and PPV. Discussion and Conclusion: Greater transparency is needed about who the respondent is when the term “parents” is used. The SDQ is an important supplement to service-as-usual assessments by social care professionals.