[1] Ghent Univ Hosp, Dept Gen Internal Med, Ghent, Belgium
[2] Ghent Univ Hosp, Dept Phys & Rehabil Med, Ghent, Belgium
[3] Catholic Univ Louvain, Dept Occupat Environm & Insurance Med, Louvain, Belgium
[4] Univ Ghent, Dept Gen Practice & Primary Hlth Care, Ghent, Belgium
[5] Serv Specialized Guidance Persons Special Needs G, Ghent, Belgium
[6] Christian Sickness Fund, Med Dept, Brussels, Belgium