Supporting older people to make informed cancer screening decisions

Abstract

Decisions about whether older adults should screen for cancer or not are complex due to the uncertain benefit-harm trade-off. Compared to younger, healthier adults, older adults with limited life expectancy, frailty and/or comorbidity are less likely to benefit from early detection through reduced morbidity and mortality. They are more likely to be overdiagnosed with a screen-detected cancer that my never cause symptoms or death, which can lead to overtreatment. Guidelines recommend an age after which cancer screening should stop in countries with national screening programs, or individualized screening decisions based on life expectancy and health status. However, people 75+ years continue to be screened, including those with limited life expectancy. Supporting informed choice is a key element of individualising screening decisions for older adults. Further research is needed to understand how interventions can be developed and implemented internationally to support informed screening decisions for older adults.

Aims: This thesis examines how to support older adults to make informed cancer screening decisions using a mixed-methods approach, with a focus on breast, cervical, prostate and bowel screening. More specifically, this thesis aimed to:

1) Summarise the existing evidence on the factors associated with older adults’ cancer screening decisions,

2) Summarise the existing evidence on the factors associated with clinicians’ cancer screening recommendations for older adults,

3) Explore GPs’ experiences of discussions and perceived roles in older adults’ decision-making about cancer screening,

4) Explore older adult (70 years) perspectives and views on continuing or stopping cancer screening beyond the upper age of guideline recommendations in Australia,

5) Conduct a randomise controlled trial to develop and test an intervention to support informed choice about cancer screening for older adults.