The development of a financial toxicity patient-reported outcome instrument (PRO) in cancer.
6612 Background: Considering patients' (pts) subjective experience is essential for optimal decision making and care. However, despite increasing recognition of the impact of costs on oncology care, there is no accepted and validated PRO that specifically describes the financial burdens cancer pts experience. Methods: A financial toxicity PRO in advanced cancer pts undergoing treatment was developed in 3 stages. Stage 1: literature review and semi-structured qualitative interviews with pts for item generation; items were classified into 5 theoretical domains (financial, resources, affect, coping and family); draft items were examined for redundancy. Stage 2: pts assessed the items for readability and importance to their quality of life via two Likert scales (0 – 3 scales) to generate an importance score; items were ranked by decreasing importance score until at least 3 items per theoretical domain had been retained. Stage 3: pilot-testing assessing inter-item (IIC) and item–total (ITC) correlations to identify redundancy (Spearman’s rho >0.7, p<0.05) and statistically unrelated content; items were formatted in accordance with the Functional Assessment of Cancer Therapy (FACT) quality of life measure, with a 7-day time window and a 5-point Likert scale. Subject data on tumor type, age, gender, race, income, insurance type and educational level were collected. Results: 132 pts (20 in stage 1, 45 in stage 2 and 67 in stage 3) were approached and 101 agreed to participate. Stage 1: literature review, 20 pts, and 6 investigators generated 98 items, which were reduced to 58 due to redundancy. Stage 2: 35 pts ranked the items for importance, and 30 items were retained. The mean importance score was 1.83 (range 1.04 – 2.11). Stage 3: 46 pts completed the 30-item instrument. Their mean age was 61 years; 59% were male and 53% had private or employer purchased insurance; 14 items were excluded due to high IIC and 3 were excluded due to non-significant ITC, resulting in a 13-item PRO. The mean IIC and ITC of the final items were 0.373 and 0.645, respectively. Conclusions: A 13-item financial toxicity PRO has been developed in 101 pts with advanced cancers. This instrument will undergo validation as a subscale of the FACT in a larger cohort of cancer pts.