OP-22 Measuring the true cost of informal cancer caregiving: development of a co-designed economic assessment tool

<h3>Background</h3> Recognised as the ‘foundation of the palliative care workforce’, informal caregivers disproportionately carry the burden of caring for patients with cancer, providing an estimated 75–90% of home-based care.¹ Current economic evaluations of health services and interventions are based on the benefits to the formal healthcare system, while the financial impact on informal caregivers is routinely overlooked. This lack of a societal approach precludes a more nuanced understanding of the drivers of burden experienced by caregivers and does not account for direct or indirect costs borne by caregivers, such as the impact on employment. To date, no standardised instrument exists to understand the economic impact of informal caregiving for cancer patients at the end-of-life. <h3>Aim</h3> To co-design a questionnaire that comprehensively captures the resources incurred by caregivers for cancer patients at the end-of-life To assess its feasibility, acceptability and face validity. <h3>Methods</h3> This is a qualitative study conducted in three phases: Semi-structured interviews conducted with caregivers to explore the depth and breadth of resources used in day-to-day life. Supported by economic theory, themes were grouped into direct and indirect costs and broader themes identified inductively according to the principles outlined by Braun and Clarke.² Questionnaire design by a community advisory group (CAG) comprised of caregivers and community-based clinicians using the findings from phase one, previous literature and lived experience. Questionnaire piloting and psychometric testing using cognitive-interviewing techniques to assess its feasibility, acceptability and face validity <h3>Results</h3> For caregivers of someone with cancer who has accessed palliative care, direct cost categories include home environment, food, equipment, medications, transport, healthcare, insurance and funeral and faith-based costs. Indirect cost categories include carer time, family and friend time, employment absenteeism and presenteeism, own health impacts, and leisure or opportunity costs. These categories informed the final questionnaire content, which consists of eight domains with 36 questions that meaningfully capture the economic impact of informal caring for cancer patients at the end-of-life. The initial pilot results have found the tool to be feasible, acceptable and valid. <h3>Conclusions/Discussion</h3> This tool has the potential to shape how we value informal caregivers by contributing data informed by a societal perspective to future economic evaluations for provision of care in the palliative and end-of-life phase. <h3>References</h3> Gardiner C, Robinson J, Connolly M, Hulme C, Kang K, Rowland C, Larkin P, Meads D, Morgan T, Gott M. Equity and the financial costs of informal caregiving in palliative care: a critical debate. <i>BMC palliative Care</i> 2020;<b>19</b>(1):71. https://doi.org/10.1186/s12904-020-00577-2 Braun V, Clarke V. Using thematic analysis in psychology. <i>Qualitative Research in Psychology</i> 2006;<b>3</b>(2):77–101. https://doi.org/10.1191/1478088706qp063oa Funded by Bethlehem Griffiths Research Foundation (BGRF) and St. Vincent’s Hospital Research Endowment Fund