Received: 5 April 2018
Accepted: 9 October 2018
First Online: 16 October 2018
Ethics approval and consent to participate
: The VU University Medical Ethical Committee approved the study protocol (VUmc 2015.136). No identifying participant information was collected for the purpose of this study, and written informed consent was signed by one parent and the participating student.
: Consent for publication was obtained from all included participants.
: The authors declare that they have no competing interests.
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