[1] St Elizabeth Hosp, Tilburg, Netherlands
[2] Catharina Hosp, Eindhoven, Netherlands
[3] Univ Med Ctr Utrecht, Utrecht, Netherlands
[4] Univ Med Ctr Utrecht, Julius Ctr Hlth Sci & Primary Care, Utrecht, Netherlands
[5] Diakonessenhuis Utrecht, Utrecht, Netherlands
[6] Schweitzer Ziekenhuis, Dordrecht, Netherlands
[7] AZ St Lucas, Ghent, Belgium
[8] Univ Groningen, Univ Med Ctr Groningen, Dept Epidemiol, NL-9713 AV Groningen, Netherlands