P. Craig, P. Dieppe, S. Macintyre, S. Michie, I. Nazareth, and M. Petticrew. BMJ (Clinical research ed.), (January 2008)4737<m:linebreak></m:linebreak>LR: 20081117; GR: Medical Research Council/United Kingdom; JID: 8900488; CIN: BMJ. 2008;337:a1937. PMID: 18945728; CIN: BMJ. 2008;337:a2473. PMID: 19001487; epublish;<m:linebreak></m:linebreak>Intervenció/placebo.