This research project was run jointly by the University of Stirling and the Scottish Bowel Screening Centre. The research was funded by a grant from the Chief Scientist Office, Scotland of £207,430 (ref: CZH/4/793). This project has the full support of both the Scottish Bowel Screening Programme Board and the Detect Cancer Early Programme.


Colorectal cancer (CRC) is the second leading cause of cancer deaths in the UK. Screening is key to early detection.  The Scottish programme of CRC screening is running successfully, and involves all adults aged between 50 and 74 being invited to post back a faecal sample for testing every 2 years. However, screening uptake is sub-optimal, often below 50%. Between November 2009 and October 2011, for instance, the kit return rates ranged from 39% for males in the most deprived socio-economic groups up to 67% for females in the least deprived groups. 

Previous research

This research follows on from a previous project conducted by a team at the screening centre, which resulted in a 5% increase in screening uptake (Libby et al., 2011). This was a large, randomised controlled trial (RCT) which tested the efficacy of a simple pre-notification letter embedded within the national colorectal cancer screening programme. 60,000 Scottish adults aged 50-74 years were randomly allocated to one of 3 conditions: standard invitation (no pre-notification), simple pre-notification letter posted two weeks before the Faecal Occult Blood test (FOBT) kit, and pre-notification letter plus a more detailed information booklet. Uptake was significantly higher with both the pre-notification letter (59.0%) and the letter plus booklet (58.5%), compared with the usual no prior notification method of invitation (53.9%).

Reference: Libby G, Bray J, Champion J, Brownlee LA, Birrell J, Gorman DR, Crighton EM, Fraser CG, Steele RJ: Prenotification increases uptake of colorectal cancer screening in all demographic groups: a randomized controlled trial. J Med Screen 2011, 8: 249.

As a result of these findings, all individuals invited for screening are now sent a standard pre-notification letter 2 weeks before being sent a FOBT by post to complete at home, and then return to the laboratory at the Scottish Bowel Screening Centre in Dundee for analysis.

Project Summary

The current project follows on from this previous research with a brief, psychological questionnaire-based intervention, included with the pre-notification letter.

Recent research has shown that asking people to consider the consequences of not participating in screening, can lead to a significant increase in screening uptake. People’s attitudes towards health and bowel screening may also influence their decision to complete their bowel screening kit.

In this project, we compared the effects of including different questionnaires along with the pre-notification letter, in a large RCT with 60,000 members of the general public. The primary outcome was test kit return. It is estimated that a 5% increase in FOBT screening uptake could translate into approximately 11 additional cancers diagnosed per 100,000 of the target population. Therefore, if the current intervention resulted in a significant increase in CRC screening returns, this would represent a rare example of a theoretically-driven, simple intervention that could result in earlier detection of CRC and many more lives saved.


Dr Julie Chambers was appointed as post-doctoral Research Fellow on the ARTICS trial. She was responsible for the day-to-day management and running of the trial. She is a very experienced research Health Psychologist who recently ran the IAMSS (Improving Medication Adherence in Stroke Survivors) randomised controlled trial (IAMSS). She also has experience of evaluating the long-term outcome of cognitive behaviour therapy clinical trials.

The study protocol is available as an open-access article from:

The research ran from October 2012 to May 2014.


Participants were randomly allocated to one of three groups: 1) no questionnaire (Control), 2) Health Locus of Control questionnaire (HLOC) or 3) anticipated regret questionnaire (AR). Primary outcome was return of the FOBT test kit within 6 months. Secondary outcomes included intention to return the test kit, perceived disgust (the ICK factor), perceived benefit (PB), and beliefs about control over one’s health (HLOC). Questionnaires were sent alongside the current standard pre-notification letter.

Key Results

60,000 people were randomised to one of the 3 treatment group; 59,366 received the pre-notification letter/ questionnaire and were included in the analysis (the others had moved out of Scotland, withdrawn from the screening programme or the letter/questionnaire was undelivered). There were no differences in the percentage of people returning an FOBT test kit between treatment groups (Control: 57.3%, HLOC: 56.9%, AR: 57.4%). Older (compared to younger) people, women (compared to men) and people from lower (compared to higher) levels of deprivation were all more likely to return their test kit. People who had previously returned one or more test kits and/or had previously failed to return their kit on fewer invited occasions were also much more likely to return their current kit.

13,645 (34.2%) people returned completed questionnaires. Most (90.8%) people who returned their questionnaire also returned their kit which is likely related to the fact that most of those returning questionnaires reported very strong intentions to return their kit. Those reporting lower perceived disgust (ICK) about completing their kit and higher anticipated regret ( AR) at not completing it reported higher intentions and were more likely to return their kit. The secondary outcomes of perceived benefit and Health Locus of Control were not associated with kit return.

Amongst questionnaire returners who reported less than strong intentions to return their FOBT kit (and therefore those who may have been most open to influence from the intervention), kit return was around 4% higher in the AR (84.6%) versus the HLOC group (80.4%), but there was no difference for those reporting strong intentions (AR: 95.3%, HLOC: 94.3%). The difference in those reporting low intentions was greatest (7.6% difference) in the lowest socioeconomic group.

The main results are now published:

O’Carroll, R.E., Chambers, J.A., Brownlee, L., Libby, G., Steele, R.J.C. (2015).  Anticipated regret to increase uptake of colorectal cancer screening (ARTICS): a randomised controlled trial. Social Science and Medicine, 142, 118-127. DOI:


We have shown that psychological concepts including AR and perceived disgust (ICK) are important factors in determining FOBT uptake. However, there was no overall simple effect of sending out an AR questionnaire, suggesting that many people may not have read their questionnaire and hence were not exposed to the AR intervention.

Nonetheless, AR was effective at increasing FOBT uptake (by 4.2%) for people definitely exposed to the intervention (i.e. returned a questionnaire) whom we wished to target i.e. those who had less than strong intentions to return their kit. This difference was even greater in the lowest socio-economic group (7.6%). As it is estimated that a 5% increase in FOBT uptake may translate into around 11 additional cancers diagnosed per 100,000 of the target population, this observed increase may be clinically important, providing it could be more widely achieved.


If you have any queries about the project, please do not hesitate to contact Dr Julie Chambers or Professor Ronan O'Carroll.