Carlene Wilson – CCSA Chair of Cancer Prevention (Behavioural Science); Flinders Centre for Innovation in Cancer, Flinders University of South Australia
Published 13 January 2014
The National Bowel Cancer Screening Program (NBSCP) – participation rates
Bowel cancer is one of the most common forms of cancer in Australia but it can be successfully treated if identified early in its progression. The use of the Fecal Occult Blood Test (FOBT) by people aged 50 years and above to detect the presence of minute levels of blood in the stool is a cost-effective strategy for managing population risk. Despite this, government statistics suggest that, at the moment, fewer than 40 per cent of bowel cancers are detected early and around 80 Australians die each week from the disease (see National Bowel Cancer Screening Program – About the program).
The National Bowel Cancer Screening Pilot Program ran between late 2002 and mid 2004 with the aim of testing the feasibility, acceptability and cost-effectiveness of bowel cancer screening designed around the provision of an FOBT to age-based subgroups of people delivered through a centralized invitation system. Three sites were utilized in the pilot; suburbs in Melbourne and Adelaide, and the town of Mackay in Queensland. Results were encouraging, though less than optimal, with a rate of 45.4 per cent in the pilot phase. As with most health behaviours, women participated more than men (47.4 and 43.4 per cent respectively). In the pilot, 9 per cent of participants returned a positive FOBT result. Phase One was rolled out after the pilot and achieved an overall participation rate of 38.7 per cent, with the rate staying relatively stable at the end of the most recent Phase Two (38.4 per cent). It has been suggested that decreased participation rates, post pilot, reflect the inclusion of younger cohorts who, like men and people from a non-English speaking background, are less likely to participate.
By way of comparison, uptake in the first round of the English bowel cancer screening pilot program was 61.8 per cent although this reduced to 57 per cent in the second round, and then increased to 58.7 per cent in the third and final pilot round. It is important to note participants’ registered NHS general practitioners were integral in the delivery of this program and research indicates recommendation from a trusted health provider is a key predictor of participation.
GP endorsement of bowel cancer screening
General Practitioners have a powerful influence on the health decision-making of older Australians and research indicates that their endorsement of bowel cancer screening is one of the strongest demonstrated influences on participation. The attitude of Australian GPs to bowel cancer screening, however, has not always been uniformly positive. For example, a study undertaken in 1996,1 before the introduction of the pilot program, and involving a survey of a national random sample of 1271 (response rate 67%), indicated that many doctors were concerned about the FOBT with only 38% rating the test effective. A smaller survey study2 undertaken with 692 Queensland GPs (41% response rate) in 2004 indicated that 50.5% of respondents would support a population screening program that used the FOBT. These results suggested that, at least in Queensland, attitudes had improved significantly in the intervening period. A survey with 1500 GPs undertaken in the same state in 20063 (55.6% response rate) suggested some levelling out of the approval rate with 53% supporting the use of the FOBT with asymptomatic people aged 50 and over.
The size of the current GP disapproval rate is unknown but it is likely that this, at least partly, influences current decision-making by some people in the population of NBCSP non-participants. Work undertaken by Graeme Young and Steve Cole at the Repatriation General Hospital and Flinders University, suggests that GP endorsement improves uptake of an initial offer of an FOBT kit by as much as 8%4 and that this advantage persists over three repeated invitations to screening rounds5.
The most recent survey of GPs’ attitudes and practices was completed in 2011 by 212 GPs in the Sydney South West Area Health Service6 (invited eligible sample size 606, response rate 36%). The results indicated that support for use of the FOBT had continued to improve with 87% of participants in the study agreeing that use of the FOBT for bowel cancer screening in average-risk patients improved survival. Notwithstanding this improvement, related clinical practice varied with differences reported for screening starting age, screening frequency, and use of FOBT for other purposes (e.g., investigation of anemia, altered bowel habits). Additionally, the results indicated that likelihood of recommending FOBT use varied between immigrants and non-immigrant patient groups with the former receiving less endorsement and GPs reporting poorer participation.
Barriers to GPs’ recommendation to screen were also identified. These barriers were, in order of prevalence; lack of time (31.6%), confusing screening guidelines (21.5%), difficulties organizing an interpreter (21.3%), difficulties finding a specialist who speaks the same language as patient (19.7%), perceived inaccuracy of the FOBT (19.1%), lack of remuneration (18%), not speaking the same language (12%) and lack of interest by the doctor (10%).
Expansion of the program
The attitudes to, and practices of, GPs with regard to bowel cancer screening will continue to be a vital influence on participation rates both within and outside of the NBCSP. The 2012-13 Federal Budget committed the Australian Government to the expansion of the program to include Australians turning 60 years of age from 2013, and those turning 70 from 2015. Additionally, the future program will implement a phased introduction of biennial screening in 2017-18. The aim is for all Australians aged between 50 and 74 years to be offered free screening every two years, consistent with the recommendations of the National Health and Medical Research Council. The role of the GP in the delivery of the NBCSP is clearly described in the screening pathway documentation (see National Bowel Cancer Screening Program: Participant’s Screening Pathway [PDF]). Less clearly defined is the critical contribution GP endorsement of screening plays to uptake rates and rescreening participation. GPs who initiate discussions about screening with underserved population segments in particular (e.g., those aged between 50 and 55, men, and people from a non-English speaking background) are in a unique position to decrease inequity in health outcomes and improve morbidity and mortality from bowel cancer.
- M.J. Sladden & J.E. Ward (1999). Australian general practitioners’ views and use of colorectal cancer screening tests. Medical Journal of Australia, 170 (3), 110-113.
- S. Tong, K. Hughes, B. Oldenburg, & C. Del Mar (2004). Would general practitioners support a population-based colorectal screening programme of faecal-occult blood testing? Internal Medicine Journal, Sep-Oct; 34 (9-10), 532-538.
- P.H. Youl, C. Jackson, B. Oldenburg, C. Brown, J. Dunn & J. Aitken (2006). Attitudes, knowledge and practice of CRC screening among GPs in Queensland. Australian Family Physician, 35 (7), 547-550.
- S.R. Cole, G.P. Young, D. Byrne, J.R. Guy, and J. Morcom (2002). Participation in screening for colorectal cancer based on faecal occult blood test is improved by endorsement by the primary care practitioner. Journal of Medical Screening, 9 (4), 147-152.
- I.T. Zajac, A.H. Whibley, S.R. Cole, D. Byrne, J. Gou, J. Morcom & G.P.Young. (2010). Endorsement by the primary care practitioner consistently improves participation in screening for colorectal cancer: a longitudinal analysis. Journal of Medical Screening, 17, 19-24.
- J.H. Koo, M.Y. You, K. Liu, M.D. Athureliya, C.W.Y. Tang, D.M. Redmond, S.J. Connor, & R.W.L. Leong (2012). Colorectal cancer screening practise is influenced by ethnicity of medical practitioner and patient. Journal of Gastroenterology and Hepatology, 27, 390-396.