Measuring financial toxicity as a clinically relevant patient‐reported outcome: The validation of the COmprehensive Score for financial Toxicity (COST)

Abstract

BACKGROUNDCancer and its treatment lead to increased financial distress for patients. To the authors' knowledge, to date, no standardized patient‐reported outcome measure has been validated to assess this distress.METHODSPatients with AJCC Stage IV solid tumors receiving chemotherapy for at least 2 months were recruited. Financial toxicity was measured by the COmprehensive Score for financial Toxicity (COST) measure. The authors collected data regarding patient characteristics, clinical trial participation, health care use, willingness to discuss costs, psychological distress (Brief Profile of Mood States [POMS]), and health‐related quality of life (HRQOL) as measured by the Functional Assessment of Cancer Therapy: General (FACT‐G) and the European Organization for Research and Treatment of Cancer (EORTC) QOL questionnaires. Test‐retest reliability, internal consistency, and validity of the COST measure were assessed using standard‐scale construction techniques. Associations between the resulting factors and other variables were assessed using multivariable analyses.RESULTSA total of 375 patients with advanced cancer were approached, 233 of whom (62.1%) agreed to participate. The COST measure demonstrated high internal consistency and test‐retest reliability. Factor analyses revealed a coherent, single, latent variable (financial toxicity). COST values were found to be correlated with income (correlation coefficient [r] = 0.28; P<.001), psychosocial distress (r = ‐0.26; P<.001), and HRQOL, as measured by the FACT‐G (r = 0.42; P<.001) and by the EORTC QOL instruments (r = 0.33; P<.001). Independent factors found to be associated with financial toxicity were race (P = .04), employment status (P<.001), income (P = .003), number of inpatient admissions (P = .01), and psychological distress (P = .003). Willingness to discuss costs was not found to be associated with the degree of financial distress (P = .49).CONCLUSIONSThe COST measure demonstrated reliability and validity in measuring financial toxicity. Its correlation with HRQOL indicates that financial toxicity is a clinically relevant patient‐centered outcome. Cancer 2017;123:476–484. © 2016 American Cancer Society.

Unmet need for clinician engagement regarding financial toxicity after diagnosis of breast cancer

“…Scholars have already developed useful tools for the rigorous evaluation of financial experiences that are ideally suited as endpoints in studies that seek improvement of financial burden. 24 …”

Identifying subgroups of well‐being among patients with cancer: Differences in attitudes and preferences around surveillance after curative‐intent surgery

“…Levels of patient financial toxicity were assessed using the COmprehensive Score for Financial Toxicity (COST), from the Functional Assessment of Chronic Illness Therapy (FACIT) measurement system. The COST scale has 11 items with strong internal validity (Cronbach's alpha = .90) . Psychosocial well‐being was assessed with the emotional, family/social, and functional subscales from the General Functional Assessment of Cancer Therapy Questionnaire (FACT‐G).…”

Understanding, measuring, and addressing the financial impact of cancer on adolescents and young adults

“…(4) Have you been unable to cover the cost of medical care visits? Even briefer is the single item from the European Organisation for Research and Treatment of Cancer QLQ‐Q30 which asks, “Has your physical condition or medical treatment caused you financial difficulties?” A more psychometrically robust but relatively brief measure of financial hardship is the Comprehensive Score for Financial Toxicity measure, an 11‐item self‐report measure of the financial impact of illness . Recent psychometric testing has supported the internal consistency, test‐retest reliability, and convergent and divergent validity of the scale . Although the validation sample included 51 participants who were 50 years or less in age, there was no specific focus on AYAs.…”