General population reference values for the Functional Assessment of Cancer Therapy-Lung and PROMIS-29

Therapeutic advances in lung cancer have turned attention toward patient-reported outcome measures (PROMs) as important clinical outcomes. The Functional Assessment of Cancer Therapy-Lung (FACT-L) is a common endpoint in lung cancer trials. This study calculated FACT-L reference values for the United States (US) general population.

Adults from the US general population (N = 2001) were surveyed between September 2020 and November 2020. Surveys contained 126 questions, including the FACT-L [36 items; FACT-G and four subscales (Physical Well-Being [PWB], Social Well-Being [SWB], Emotional Well-Being [EWB], and Functional Well-Being [FWB]) and the Lung Cancer Subscale (LCS), and a Trial Outcome Index (TOI)]. Reference values for each FACT-L scale were calculated with means for the total sample and separately for participants with: no comorbidities, COVID-19 as only comorbidity, no COVID-19.

In the total sample, the reference scores were as follows: PWB = 23.1; SWB = 16.8; EWB = 18.5; FWB = 17.6; FACT-G = 76.0; LCS = 23.0, TOI = 63.7, and FACT-L Total = 99.0. Scores were lower for those reporting a prior diagnosis of COVID-19, especially for SWB (15.7) and FWB (15.3). SWB scores were lower than previous references values.

These data provide US general adult population reference value set for FACT-L. While some of the subscale results were lower than those found in the reference data for other PROMs, these data were obtained in a more contemporaneous time frame juxtaposed with the COVID-19 pandemic and may represent a new peri-pandemic norm. Thus, these reference values will be useful for future clinical research.