Authors: Dirk Timmerman; Lieveke Ameye; Daniela Fischerova; Elisabeth Epstein; Gian Benedetto Melis; Stefano Guerriero; Caroline Van Holsbeke; Luca Savelli; Robert Fruscio; Andrea Alberto Lissoni; Antonia Carla Testa; Joan Veldman; Ignace Vergote; Sabine Van Huffel; Tom Bourne; Lil Valentin Journal: BMJ Date: 2010-12-14