Anna Santos Salas ^1* Nahyeni Bassah ¹ Anna Pujadas Botey ^2,3 Paula Robson ^2,4 Julia Beranek ¹ Iqmat Iyiola ¹ Megan Kennedy ⁵

• ¹ Faculty of Nursing, College of Health Sciences, University of Alberta, Edmonton, Canada
• ² Cancer Strategic Clinical Network, Alberta Health Services, Edmonton, Alberta, Canada
• ³ School of Public Health, University of Alberta, Edmonton, Alberta, Canada
• ⁴ Cancer Research & Analytics, Cancer Care Alberta, Alberta Health Services, Edmonton, Canada
• ⁵ Geoffrey and Robyn Sperber Health Sciences Library, University of Alberta Library, Edmonton, Alberta, Canada

Background: Underserved populations both globally and in Canada face serious cancer inequities that result from systemic economic, environmental, and social conditions. These pose barriers in access to cancer care and lead to suboptimal cancer care experiences and outcomes. Knowledge of effective interventions to improve access to cancer care is needed to inform the design of tailored interventions for these populations. Aim: To identify interventions and programs to improve access to cancer care for underserved populations in high income countries with universal health coverage (UHC) and the United States (US) throughout the cancer care continuum. Methods: We conducted a systematic review following the PRISMA standards. We searched Medline, EMBASE, PsycINFO, CINAHL, Scopus, and the Cochrane Library. Inclusion criteria: quantitative and qualitative studies published in English in the last 10 years (2013-2023), describing interventions/programs to improve access to cancer care for underserved populations (18 years and over). We included studies in the US given the body of scholarship on equity in cancer care in that country. Screening, data extraction and analysis were undertaken by two independent reviewers. Results: Our search yielded 7,549 articles, and 74 met the inclusion criteria. Of these, 56 were conducted in the US, 8 in Australia, 6 in Canada, and 4 in the UK. Most (90.5%) were quantitative studies and 47.3% were published between 2020-2023. Seven types of interventions were identified: patient navigation, education and counselling, virtual health, service redesign, financial support, improving geographical accessibility and multicomponent interventions. Interventions were mainly designed to mitigate language, distance, financial, lack of knowledge and cultural barriers. Most interventions focused on access to cancer screening, targeted rural populations, racialized groups and people with low socioeconomic status, and were conducted in community-based settings. The majority of interventions or programs significantly improved access to cancer care. Conclusion: Our systematic review findings suggest that interventions designed to remove specific barriers faced by underserved populations can improve access to cancer care. Few studies came from countries with UHC. Research is required to understand tailored interventions for underserved populations in countries with UHC.