Strengths and Difficulties Questionnaire (SDQ)- parent form The Dutch version of the Strengths and Difficulties Questionnaire - Parent Form for children (SDQ) [3, 18, 24, 25] was used. It consists of 25 items describing positive and negative attributions of children and adolescents that can be allocated to five scales of five items each: Emotional symptoms, Conduct problems, Hyperactivity-Inattention, Peer problems and Prosocial behaviour. Each item has to be scored on a 3-point Likert with 0 ‘not true’,1‘somewhat true’ and 2 ‘certainly true’. Scale scores are computed by summing the scores on the scale items (range 0–10).