Core functions of a financial navigation intervention: An in-depth assessment of the Lessening the Impact of Financial Toxicity (LIFT) intervention to inform adaptation and scale-up in diverse oncology care settings.

Background: Lessening the Impact of Financial Toxicity (LIFT) is an intervention designed to address financial toxicity (FT) and improve cancer care access and outcomes through financial navigation (FN). FN identifies patients at risk for FT, assesses eligibility for financial support, and develops strategies to cope with those costs. LIFT successfully reduced FT and improved care access in a preliminary study among patients with high levels of FT in a single large academic cancer center. Adapting LIFT requires distinguishing between core functions (components that are key to its implementation and effectiveness) and forms (specific activities that carry out core functions). Our objective was to complete the first stage of adaptation, identifying LIFT core functions. Methods: We reviewed LIFT's protocol and internal standard-operating procedures. We then conducted 45-90 min in-depth interviews, using Kirk's method of identifying core functions, with key LIFT staff ( Results: Six intervention core functions (i.e., what makes LIFT effective) and five implementation core functions (i.e., what facilitated LIFT's implementation) were identified to be sufficient to reduce FT. Intervention core functions included systematically cataloging knowledge and tracking patient-specific information related to eligibility criteria for FT relief. Repeat contacts between the financial navigator and participant created an ongoing relationship, removing common barriers to accessing resources. Implementation core functions included having engaged sites with the resources and willingness necessary to implement FN. Developing navigators' capabilities to implement LIFT-through training, an established case management system, and connections to peer navigators-were also identified as implementation core functions. Conclusion: This study adds to the growing evidence on FN by characterizing intervention and implementation core functions, a critical step toward promoting LIFT's implementation and effectiveness.