Turning Intention Into Behaviour: The Effect of Providing Cues to Action on Participation Rates for Colorectal Cancer Screening

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in males and second in females; throughout the world over 1.2 million new CRC cases and 608,7000 deaths are estimated to have occurred in 2008 (Jemal et al., 2011). The only developed country to have demonstrated a significantly decreasing incidence in both males and females is the United States, and this is largely due to the early detection and removal of pre-cancerous lesions through CRC screening (Jemal et al., 2011). Thus, an understanding of the variables that encourage people to participate in CRC screening is important because early detection and treatment of precancerous lesions and adenomas results in a significantly higher survival rate than if treatment is delayed until physical symptoms of the condition are apparent. Population screening using a Faecal Occult Blood Test (FOBT) can facilitate the detection of CRC at its early stages. FOBT is the collective term for a guiaic FOBT (gFOBT) or a faecal immunochemical test (FIT). Both are home-based tests which, although differing in the technology utilised, involve a stool sample being sent to a laboratory to be analysed for occult blood, ideally followed by colonoscopy for those with a positive result. The cost effectiveness of FOBTs for the screening of CRC, measured as Quality Adjusted Life Years gained, is comparable to other screening procedures (Frazier et al., 2000) and more costeffective than treatment after physical symptoms are evident (Fisher et al., 2006). Randomised clinical trials have shown that both biennial and annual screening using FOBT screening reduces CRC incidence (Mandel et al., 2000) and mortality (Hardcastle et al., 1996; Kronborg et al., 2004; Mandel et al., 1993), and a systematic review concluded that FOBT screening is likely to avoid 1 in 6 colorectal cancer deaths (Hewitson et al., 2007). Effectiveness, however, depends upon yield and is critically dependent upon participation rates, which for population-based screening programs have been low, often despite high levels of intention to participate. For example, in Australia the National Bowel Cancer Screening Program, which provides people turning 50, 55 and 60 years with a free FOBT, had a participation rate in 2008 of 41% of the eligible population (AIHW, 2010). In England, the second round (2003–2005) of the pilot bowel cancer screening program had a