Utilizing the Question-behaviour Effect to Promote Bowel Cancer Screening: a Randomized Controlled Trial

Abstract

Question-behaviour effect (QBE) refers to the finding that answering questions about behaviour can increase behaviour itself. We investigated the QBE and motivation as methods to increase bowel cancer screening. Participants (N= 10693) were randomized into four conditions and received a Theory of Planned Behaviour questionnaire only or combined with the offer of a £5 incentive for returning the questionnaire. Two control groups received either a demographic questionnaire or no contact. Behaviour was objectively measured by whether a bowel screening test kit was returned within 19 weeks. Total attendance was highest (61.5%) in the no contact control condition which was marginally significantly higher than the QBE condition (58.9%). Significantly more questionnaire returners in the QBE condition (97.3%) attended than the demographic control (94.5%). The incentive did not affect motivation and all questionnaire returners had high levels of motivation. These findings suggest the QBE cannot be applied as a population-wide intervention to increase bowel cancer screening, but for some individuals , simply completing a questionnaire can increase their likelihood of carrying out screening.