Paul Hewitson|Alison Ward|Carl Heneghan|Stephen P Halloran|David Mant
Primary care endorsement letter and a patient leaflet to improve participation in colorectal cancer screening: results of a factorial randomised trial
University of Oxford|University of Oxford|University of Oxford|University of Surrey|University of Oxford
trial aimed investigate whether general practitioners gp letter encouraging participation explicit leaflet explaining complete faecal occult blood test fobt included england bowel cancer screening programme invitation materials would improve uptakea randomised controlled 2 2 factorial trial conducted south england overall 1288 patients registered 20 gps invited screening october 2009 participated trial participants randomised either gps endorsement letter andor enhanced information leaflet fobt kit primary outcome verified return test kit within 20 weeksboth gps endorsement letter enhanced procedural leaflet increased participation 6 gps letter 58 95 ci 4178 leaflet 60 95 ci 4381 basis intentiontotreat analysis random effects logistic regression model confirmed important interaction two interventions estimated adjusted rate ratio 111 p0038 gps letter 112 p0029 leaflet absence interaction additive effect receiving gps letter leaflet 118 95 ci 8516 confirmed perprotocol analysis indicated insertion electronic gps signature endorsement letter associated increased participation p0039including endorsement letter patients gp explicit procedural leaflet could increase participation english bowel cancer screening programme 10 relative improvement 20 current performance