Table 2 Participant characteristics (n = 1028)

Gender (%)

   Boys

51.2

   Girls

48.8

Year (%)

First

35.3

Second

64.7

Educational track (%)

Lower subtrack of prevocational education

22.7

Higher subtracks of prevocational education

77.3

Ethnic status (%)

Both parents born in het Netherlands

79.2

One or both parents born abroad

20.8

Mean age in years (SD)

13.0 (0.8)

Socio-economic position score based on postal code area (scale 4 to -4, low to high)

-0.04(0.86)