title: Psychometric properties of the parent strengths and difficulties questionnaire in the general population of German children and adolescents: results of the BELLA study.
abstract: BACKGROUND
  The strengths and difficulties questionnaire (SDQ) is a brief screening instrument that addresses negative and positive behavioural attributes of children and adolescents in the age range of 4-16 years and can be completed by parents, teachers, and as a self-report. Furthermore, the impact supplement of the extended SDQ surveys for perceived problems, impact, and burden.
  
  
  OBJECTIVE
  This paper aims to examine the psychometric properties of the parent form and to investigate differences in the SDQ scores for sociodemographic and socioeconomic subgroups. Patterns of association with other measures of mental health and descriptive comparison with the first normative sample are also reported.
  
  
  METHODS
  Within the BELLA study module of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), a total of 2,406 children and adolescents aged 7-16 years as well as their parents answered the items of the SDQ and the additional impact supplement. The internal consistency of scale responses was assessed via Cronbach's alpha (alpha). Likert scale assumptions of sufficient and similar item-total correlation and item variance were investigated. The factorial validity of the SDQ measurement model was tested by means of exploratory and confirmatory factor analysis. Mean score differences between males and females, age groups (7-10 years vs. 11-16 years), and socioeconomic status groups (Winkler index) were examined via ANOVA.
  
  
  RESULTS
  Factor analysis provided an exact replication of the original five-factor SDQ subscale structure. All subscales were sufficiently homogeneous. The mean total difficulties and SDQ subscale scores of the BELLA sample did not differ from the first German normative data. Younger children were more impaired on various SDQ scales than older children, girls were more emotionally affected, and boys showed more externalising problems.
  
  
  CONCLUSIONS
  The present study confirmed the validity and reliability of the parent-reported SDQ scale structure. The SDQ was found to be a valid and helpful questionnaire for use in the framework of an epidemiological survey.
authors.affiliation: Department of Child and Adolescent Psychiatry, University of Göttingen, von-Siebold-Strasse 5, 37075, Göttingen, Germany. arothen@gwdg.de
authors.forename: Aribert
authors.initials: A
authors.lastname: Rothenberger
authors.forename: Andreas
authors.initials: A
authors.lastname: Becker
authors.forename: Michael
authors.initials: M
authors.lastname: Erhart
authors.forename: Nora
authors.initials: N
authors.lastname: Wille
authors.forename: Ulrike
authors.initials: U
authors.lastname: Ravens-Sieberer
mesh_terms: D000223:Adaptation, Psychological; D000293:Adolescent; D000296:Adolescent Psychiatry / Q000706:statistics & numerical data; D017677:Age Distribution; D000704:Analysis of Variance; D002648:Child; D002665:Child Psychiatry / Q000706:statistics & numerical data; D005163:Factor Analysis, Statistical; D005260:Female; D005858:Germany / Q000453:epidemiology; D006306:Health Surveys; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000453:epidemiology*; D010290:Parents / Q000523:psychology*; D011594:Psychometrics; D015203:Reproducibility of Results; D017678:Sex Distribution; D012959:Socioeconomic Factors; D013315:Stress, Psychological / Q000453:epidemiology* / Q000523:psychology; D011795:Surveys and Questionnaires / Q000592:standards*