Oral Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2026

Optimising investment in colorectal cancer screening promotion interventions in Australia: a modelling study (146402)

Anna Kelly 1 , Han Ge 1 , Joachim Worthington 1 , Karen Canfell 1 , Eleonora Feletto 1 , Jie-Bin Lew 1 , MAIL, GP, SCALE Investigator Team 1 2 3 4 5 6 7 8 9 10 11 12 13 14
  1. Cancer Elimination Collaboration, Sydney School of Public Health, The University of Sydney, Newtown, NSW, Australia
  2. Cancer Institute NSW, Sydney, NSW, Australia
  3. University of New South Wales, Sydney, NSW, Australia
  4. Centre for Behavioural Research in Cancer, Cancer Council Victoria, Melbourne, Victoria, Australia
  5. Australia School of Psychological Sciences, The University of Melbourne, Melbourne, Victoria, Australia
  6. Cancer Council Queensland , Fortitude Valley, Queensland, Australia
  7. Melbourne School of Population and Global Health, Centre for Epidemiology and Biostatistics, University of Melbourne, , Melbourne
  8. Cancer Council Victoria, Melbourne, Victoria
  9. School of Public Health, University of Adelaide, Adelaide, South Australia
  10. Cancer Council Western Australia, Perth, Western Australia
  11. Cancer Council Australia, Sydney, NSW
  12. Cancer Council NSW, Sydney, NSW
  13. Queensland Health, Brisbane, Queensland
  14. The Daffodil Centre, Sydney, NSW

Aims: Participation in Australia's National Bowel Cancer Screening Program (NBCSP), a cost-effective program for reducing colorectal cancer (CRC) burden, remains low (~42%). Although interventions such as mass-media campaigns have been shown to increase participation and be cost-effective, evidence to guide investment in other participation-enhancing strategies is limited. This study estimated the health and economic impacts of interventions to increase NBCSP participation in Australia.

Methods: A targeted literature review identified studies published in 2015-2025 evaluating interventions to increase participation in faecal occult blood test (FOBT)-based CRC screening programs and reporting intervention costs. Published costs were used to estimate indicative Australian national scale-up costs where sufficient information was available. The Policy1-Bowel microsimulation model simulated NBCSP-eligible Australians aged 50-74 years in 2027 and estimated maximum cost-effective investment thresholds (MCEIT) for participation increases, based on a willingness-to-pay threshold of AUD$50,000 per life-year saved.

Results: Twelve studies met the inclusion criteria. Intervention effectiveness varied considerably across individual-, health service-, and population-level settings. Four studies (relative risks [RR]=1.01-1.30) provided sufficient data to estimate indicative Australian national scale-up costs. One intervention, general practitioner endorsement (RR=1.01), was estimated to result in 13,165 additional kits returned in 2027. Its indicative scale-up cost ($6.7 million) remained below the estimated MCEIT ($8.0 million), indicating this is likely to be a cost-effective intervention. A higher-impact telephone reminder intervention (RR=1.30) corresponded to an estimated 394,947 additional kits returned in 2027. Its estimated scale-up cost ($24.5 million) was well below the corresponding MCEIT ($185.9 million).

Conclusions: Additional investment in evidence-based interventions to increase NBCSP participation could be made while remaining cost-effective. By combining international evidence with modelling, this study provides benchmarks to support prioritisation of interventions that maximise CRC screening participation in Australia.