Cross-cultural adaptation of the PROFFIT Instrument to measure financial toxicity in people living with cancer within a UK population

Background This study aimed to develop a British version of the Patient Reported Outcomes for Fighting Financial Toxicity of Cancer (PROFFIT): originally designed to measure financial toxicity in cancer for an Italian universal healthcare system. The instrument was carefully evaluated for cross cultural equivalence, face validity and practicality. Methods A systematic approach to cross-cultural adaptation was used, including forward translation, synthesis, backward translation, consolidation of translations with an expert committee, and cognitive interviews. As part of the cognitive interview process, 18 cancer patients completed a structured interview of 60–90 min in length. Results The translated and modified PROFFIT questionnaire demonstrated good psycho-linguistic properties, including high compliance (only one item was revised for clarity), high retrieval from memory, high decision-making processes, and high response processes. Conclusion PROFFIT has been found to be functional and adaptable in a new social environment. The tool may be useful for tailoring interventions to address and measure financial hardships within the cancer population, which appear to be a current challenge for public health.