(HealthDay News) — A four-step process has been used to develop a patient-reported outcome measure of financial toxicity for cancer patients, according to a study published online June 20 in Cancer.
Jonas A. de Souza, MD, from the University of Chicago, and colleagues used a stepwise approach to develop content for a comprehensive score for financial toxicity (COST) in 155 patients undergoing treatment for advanced cancer. Content was generated via literature review and semi-structured interviews with patients (step 1); patients assessed items for importance to their quality of life (step 2); redundancy and statistically unrelated content were identified in pilot testing (step 3); and exploratory factor analysis was conducted (step 4).
The researchers identified 147 items from literature review and interviews with 20 patients, which were reduced to 58 items after review for redundancy. These items were rated by 35 patients and 30 of the 58 were retained. Forty-six patients assessed these 30 items and 14 and three, respectively, were excluded for higher inter-item and nonsignificant item-total correlations, respectively. In a factor analysis of 100 patients, two items were discarded due to poor loadings, resulting in an 11-item patient-reported outcome measure.
“The content for a financial toxicity patient-reported outcome measure was developed in 155 patients,” the authors write. “The provisional COST measure demonstrated face and content validity, as well as internal consistency, and should be validated in larger samples.”