Received: 13 July 2017
Accepted: 18 April 2018
First Online: 9 May 2018
Ethics approval and consent to participate
: The study is approved by the Medical Research and Ethics Committee of the Maastricht University Medical Centre, Maastricht, the Netherlands in 2015 (METC 15–4-032). The need for consent has been waived by the Medical Research and Ethics Committee of the Maastricht University Medical Centre because this study includes unidentifiable data and there will be no details on individuals reported.
: The authors declare that they have no competing interests.
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