Text and Data Mining valid from 2019-09-09
Received: 3 July 2019
Accepted: 2 September 2019
First Online: 9 September 2019
Ethics approval and consent to participate
: This study conforms to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a priori approval by the local Ethical Committee of the University Hospitals of Leuven.
: Not applicable.
: The authors declare that they have no competing interests.