Authors: Anton Pottegård; Maija Bruun Haastrup; Tore Bjerregaard Stage; Morten Rix Hansen; Kasper Søltoft Larsen; Peter Martin Meegaard; Line Haugaard Vrdlovec Meegaard; Henrik Horneberg; Charlotte Gils; Dorthe Dideriksen; Lise Aagaard; Anna Birna Almarsdottir; Jesper Hallas; Per Damkier Journal: BMJ Date: 2014-12-16