A randomised controlled trial of personalised decision support delivered via the internet for bowel cancer screening with a faecal occult blood test: The effects of tailoring of messages according to social cognitive variables on participation

Abstract

Background: In Australia, bowel cancer screening participation using faecal occult blood testing (FOBT) is low. Decision support tailored to psychological predictors of participation may increase screening. The study compared tailored computerised decision support to non-tailored computer or paper information. The primary outcome was FOBT return within 12 weeks. Additional analyses were conducted on movement in decision to screen and change on psychological variables. Methods: A parallel, randomised controlled, trial invited 25,511 people aged 50-74 years to complete an eligibility questionnaire. Eligible respondents (n∈=∈3,408) were assigned to Tailored Personalised Decision Support (TPDS), Non-Tailored PDS (NTPDS), or Control (CG) (intention-to-treat, ITT sample). TPDS and NTPDS groups completed an on-line baseline survey (BS) and accessed generic information. The TPDS group additionally received a tailored intervention. CG participants completed a paper BS only. Those completing the BS (n∈=∈2270) were mailed an FOBT and requested to complete an endpoint survey (ES) that re-measured BS variables (per-protocol, PP sample). Results: FOBT return: In the ITT sample, there was no significant difference between any group (χ 2(2)∈=∈2.57, p∈=∈.26; TPDS, 32.5%; NTPDS, 33%; and CG, 34.5%). In the PP sample, FOBT return in the internet groups was significantly higher than the paper group (χ 2(2)∈=∈17.01, p∈