Background: The Functional Assessment of Cancer Therapy-General (FACT-G) is a widely used quality-of-life measure. However, no studies have examined the FACT-G among patients with life-limiting illnesses who present to emergency departments (EDs). Objective: The goal of this study was to examine the psychometric properties of the FACT-G among patients with life-limiting illnesses who present to EDs in the United States. Methods: This cross-sectional study pooled data from 12 EDs between April 2018 and January 2020 (n = 453). Patients enrolled in the study were adults with one or more of the four life-limiting illnesses: advanced cancer, Congestive Heart Failure, Chronic Obstructive Pulmonary Disease, or End-Stage Renal Disease. We conducted item, exploratory, and confirmatory analyses (exploratory factor analysis [EFA] and confirmatory factor analysis [CFA]) to determine the psychometric properties of the FACT-G. Results: The FACT-G had good internal consistency (Cronbach's alpha α = 0.88). The simplest EFA model was a six-factor structure. The CFA supported the six-factor structure, evidenced by the adequate fit indices (comparative fit index = 0.93, Tucker-Lewis index = 0.92, root-mean-square error of approximation = 0.05; 90% confidence interval: 0.04 - 0.06). The six-factor structure comprised the physical, emotional, work and daily activities-related functional well-being, and the family and friends-related social well-being domains. Conclusions: The FACT-G is a reliable measure of health-related quality of life among patients with life-limiting illnesses who present to the ED. Clinical Trial Registration: NCT03325985.
Keywords: FACT-G; confirmatory factor analysis; emergency department; exploratory factor analysis; measurement invariance; patients with life-limiting illnesses.