Funding for this research was provided by:
Ministry of the Flemish Community (x)
Received: 11 May 2020
Accepted: 2 February 2021
First Online: 26 February 2021
Ethics approval and consent to participate
: The study protocol was approved by the Ethical Committee of the University of Antwerp on July 3, 2002.
: Not applicable.
: The authors declare that they have no competing interests.