[1] Univ Amsterdam, Acad Med Ctr, Emma Childrens Hosp, NL-1105 AZ Amsterdam, Netherlands
[2] Univ Amsterdam, Acad Med Ctr, Dept Social Med, NL-1105 AZ Amsterdam, Netherlands
[3] Univ Amsterdam, Acad Med Ctr, Dept Gen Practice, NL-1105 AZ Amsterdam, Netherlands
[4] TNO Qual Life Child Hlth Prevent & Phys Activ, NL-2301 CE Leiden, Netherlands