[1] Univ Antwerp Hosp, Antwerp, Belgium
[2] Univ Hosp Liege, Liege, Belgium
[3] Laval Hosp, Res Ctr, Ste Foy, PQ, Canada
[4] St Lukes Roosevelt Hosp, New York, NY USA
[5] Univ Helsinki, Cent Hosp, Helsinki, Finland
[6] Univ Hosp Geneva, Geneva, Switzerland