Received: 24 May 2019
Accepted: 28 October 2019
First Online: 4 November 2019
Ethics approval and consent to participate
: This study involved human participants. All the procedures carried out in the context of this study were in accordance with the ethical standards of our institutional and/or national research ethics committee and with the 1964 Helsinki Declaration and its amendments or comparable ethical standards. The study was approved by the ethical review board of University Medical Center Groningen, the Netherlands. Informed consent was obtained in writing from all the parents of the participating infants.
: For the purpose of this study we did not use any individual person’s data, such as images, videos, or other personal details.
: The authors declare that they have nothing to disclose, financially or otherwise. No conflicts of interest were reported.