Funding for this research was provided by:
Prinses Beatrix Spierfonds (W.OR15-09)
Metakids ING goede doelen fonds (2014-055)
Ride4Kids Foundation (191213)
Received: 3 October 2019
Revised: 13 November 2019
Accepted: 26 November 2019
First Online: 21 December 2019
Ethics approval and consent to participate
: Written informed consent was obtained from all participants, and this study was approved by the medical ethical committee of the Erasmus MC, The Netherlands.
: Not applicable.
: The authors declare that they have no competing interests.