Education level of 15-year-olds: 1. Preparatory secondary vocational education (vmbo) basic vocational or advanced vocational track; 2. Vmbo combined or theoretical track; 3. Higher general secondary education (havo) 4. Pre-university education (vwo). Practical training courses and apprenticeship programmes are not surveyed and therefore not taken into account.
The survey population comprises all children aged 15 on 1 October 2013, i.e. born between 1 October 1997 and 30 September 1998. The survey covers more than 177 thousand children, of whom 847 were adopted.