Funding for this research was provided by:
Stichting Innovatie Alliantie (Grant 2014-046PRO)
Received: 19 November 2018
Accepted: 30 August 2019
First Online: 6 September 2019
Ethics approval and consent to participate
: All participants gave written informed consent prior to participation. The study protocol was a non-medical research and no registration was required by the Medical Ethical Review Board of the Leiden University.
: Not applicable.
: The authors declare that they have no competing interests.