Received: 23 May 2019
Accepted: 25 October 2019
First Online: 9 November 2019
Ethics approval and consent to participate
: The study was conducted in accordance with common ethical standards and was approved by the appropriate institutional review board (Aufsichts- und Dienstleistungsbehoerde, reference number: 51 111-32/20-13). Informed consent was provided from the children’s caregivers. This article does not contain any studies with animals performed by any of the authors.
: Not applicable.
: The authors declare that they have no competing interests.