The Validation of the COmprehensive Score for Financial Toxicity (COST) Scale in Greek Language.

The aim of this study was to investigate the psychometric properties of the Greek version of FACIT-COST, as well as to assess the levels of financial distress of patients suffering from lung cancer in relation to their quality of life and lung cancer symptom burden. This was a cross-sectional quantitative study. A self-assessment instrument was used to gather the data. The study involved 120 lung cancer patients who were treated using chemotherapy in a day clinic of a General Hospital in Athens. Data were collected with the COST-FACIT-v2 (used to assess the patients' financial toxicity), The 12-item Health Survey (SF-12), and functional Assessment of Cancer Therapy-Lung Symptom Index Questionnaire-7 items-version 4 (FACIT-FACT-LCS). Descriptive statistics as well as exploratory factor analysis performed all the statistical analyses, which were conducted using IBM SPSS Statistics 25 and had p-values with a significance level of 0.05. The majority of the participants were male (68.3%), married or cohabitated (81.3%), and had been diagnosed with microcell cancer (90%). The factor analysis resulted in one factor that interpreted 35% of the total variance. FACT-L (r = 0.365, p < 0.001), physical component SF-12 (r = 0.184, p = 0.045), and mental health component SF-12 (r = 0.268, p = 0.003) were positively correlated to FACIT-OST, as expected. The Greek validated COST-FACIT-v2 is a reliable tool in providing rapid assessment of cancer patients' level of financial distress.