Mental health difficulties in children and adolescents: The study of the SDQ in the Spanish National Health Survey 2011-2012.

The Strengths and Difficulties Questionnaire (SDQ) is a well-known measuring instrument widely used for the assessment of mental health in children and adolescents. Relatively few studies have analysed the factor structure, the measurement invariance, and the internal consistency, including the information function of the SDQ in its parent version. The study included a large sample (N = 3828) from the Spanish National Survey (2016 were male; 52.7%). Mean age was 9.13 (SD = 3.21) with ages ranging from 4 to 14. The level of internal consistency of the scores for the Total difficulties score was 0.84, ranging between 0.75 and 0.78 for the SDQ subscales. Results from the confirmatory factor analysis showed a five-factor model as the most appropriate. Nonetheless, the fit indices were inadequate and different modifications were needed. The hypothesis of measurement invariance of the SDQ scores across gender and educational level was supported. The present study allows us to affirm that the SDQ, parent's version form, appears to be an adequate tool for the screening of emotional and behavioural problems for children and adolescents. Future research should analyse the SDQ at cross-cultural level, incorporating novel psychometric frameworks and new mental health classifications.