Funding for this research was provided by:
world childhood foundation
Received: 24 June 2021
Accepted: 20 September 2021
First Online: 25 September 2021
: The study protocol of the RCT study was approved by the Ethics Committee at the University of Ulm (#176/16). All participants and their legal guardians, if minor, were informed about the study protocol and gave their written consent prior study inclusion.
: The consent for publication was obtained from all study participants. The individual information was handled anonymous and no images or videos were employed.
: There are no competing interests.