title: Foreword.
authors.affiliation: VieCuri Medisch Centrum voor Noord-Limburg, Venlo , the Netherlands , whmkuijk@viecuri.nl.
authors.forename: Willi
authors.initials: W
authors.lastname: van Kuijk
authors.affiliation: Ziekenhuis Bronovo, Den Haag , the Netherlands , y.w.j.sijpkens@lumc.nl.
authors.forename: Yvo
authors.initials: Y
authors.lastname: Sijpkens
authors.affiliation: Hans Mak Instituut , Naarden , the Netherlands , elsboeschoten@hansmakinstituut.nl.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Boeschoten
authors.affiliation: Academisch Medisch Centrum Amsterdam, the Netherlands and Stichting Dianet, Amsterdam-Utrecht , the Netherlands , Wa.smit@amc.nl.
authors.forename: Watske
authors.initials: W
authors.lastname: Smit