Identifying latent factors in the Living With Cancer (LWC) patient-reported outcomes (PRO) tool for patients with advanced malignancies.

Abstract

150 Background: End-of-Life Care (EOLC) discussions are frequently delayed past the time of usefulness, resulting in cancer patients (pts) receiving aggressive, expensive, non-desired care. The “Living with Cancer” project has developed a 7-item, 5-level Likert scale PRO tool that evaluates, from the pt perspective, their concerns regarding performance status, pain, family/financial burden, and depression during their cancer journey. The instrument was shown to correlate well with the oncologist’s opinion of appropriateness to continue treatment and might be useful as a quality metric in guiding timing of EOLC discussions (J Palliative Med 2016). Methods: The LWC PRO was administered to 1302 pts with advanced malignancies receiving care by Regional Cancer Care Associates (NJ) between Sept 2015 and Aug 2016, with confirmation of life status in Sept 2016. Exploratory factor analysis was conducted on the LWC instrument to identify latent constructs (factors) contributing to the item scores. The data set was deemed suitable for factor analysis based on standard statistical tests, including Bartlett’s test (p < 0.001). Results: A 3-factor model comprised of factors (1) Global functioning (using 5/7 items), (2) Financial toxicity (1/7 items), and (3) Depression (1/7 items) was fitted to the data using maximum likelihood and promax rotation (p = 0.043). Factor scores were compared between the cohort of 133 pts who expired within 3 months of completing their final survey and the 1124 who remained alive after 3 months. The mean global functioning score was significantly greater (worse) in the expired cohort (p < 0.001), suggesting the PRO description of distress correlated with survival. Financial toxicity and depression factor scores did not correlate with survival. Conclusions: The 7-item LWC PRO instrument contains 5 items defined by a global functioning factor that discriminates based on 3-month overall survival. This finding adds further evidence that the 7-item PRO tool can be used to time EOLC discussions with the aim to ensure better correlation between pts’ treatment desires and delivered care. LWC may also serve as a quality metric evaluating timing of EOLC discussions.