Funding for this research was provided by:
Received: 5 January 2017
Accepted: 4 April 2018
First Online: 12 April 2018
Ethics approval and consent to participate
: The trial is registered at ClinicalTrials.gov, number NCT01432327 and ethical approval was obtained from the Medical Ethics Committee of the KU Leuven. Each participant signed an informed consent.
: All participants have consented with publication based on the informed consent.
: The use of commercial names in this manuscript is solely for informational purposes and does not represent any endorsement. The authors declare no conflict of interest.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.