[1] Aarhus Univ, Aarhus, Denmark
[2] Univ Med Ctr Hamburg Eppendorf, Hamburg, Germany
[3] Aristotle Univ Thessaloniki, Thessaloniki, Greece
[4] Austrian Natl Publ Hlth Inst, Vienna, Austria
[5] Univ Iowa, Iowa City, IA USA
[6] Royal Coll Surgeons Ireland, Dublin, Ireland