Cornelia Junghans, Gene Feder, Harry Hemingway, Adam Timmis, Melvyn Jones
Junghans C, Feder G, Hemingway H, Timmis A, Jones M.
Recruiting patients to medical research: double blind randomised trial of “opt-in” versus “opt-out” strategies
BMJ 2005; 331 :940
doi:10.1136/bmj.38583.625613.AE