Parents are asked to tick off a checkbox if the item in question is a concern [20]. The ASQ:SE has a scoring range of 0 to 255 in the 18-month version. 3) the short validated Dutch version of the Parenting Stress Index [21], called ‘Nijmeegse ouderlijke stress index – kort’ (NOSIK) [22]. The NOSIK consists of 25 items using a 6-point Likert scale ranging from ‘do not agree at all’ to ‘do completely agree’, with a scoring range of 25 to 150. 4) a partly validated questionnaire on psychological and pedagogic problems in young children which is frequently used in preventive CHC in the Netherlands: the ‘Kort Instrument voor de Psychologische en Pedagogische Probleem Inventarisatie’ (KIPPPI) [23]. This self-report questionnaire consists of 70 items grouped into a total score, and 19 yes/no items on life events.