1Thorax Centre Twente, Medisch Spectrum Twente, Enschede, The Netherlands
2Department of Cardiology, Bravis Ziekenhuis, Roosendaal, The Netherlands
3Department of Research methodology, Methods and Data Analysis, University of Twente, Enschede, The Netherlands
4Medical School Twente, Medisch Spectrum Twente, Enschede, The Netherlands
© The Author(s) 2017
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