Patient-reported outcomes in non-small cell lung cancer: psychometric evaluation of the PROMIS PF-SF 8c and NSCLC-SAQ in two phase 3 clinical trials

Physical functioning and symptom severity are important factors in the experience of people with living with non-small cell lung cancer (NSCLC). This study evaluates the reliability, validity, and meaningful within-person change (MWPC) thresholds of 2 patient-reported outcome (PRO) measures in NSCLC: the Patient-Reported Outcomes Measurement Information System (PROMIS®) Physical Function (PF) short form (SF) 8c and the Non-Small Cell Lung Cancer Symptom Assessment Questionnaire (NSCLC-SAQ).

Data came from 2 Phase 3 clinical trials among people living with NSCLC. PROMIS PF-SF analyses included data from 300 participants in the PAPILLON trial, and NSCLC-SAQ analyses included 615 participants in the MARIPOSA 2 trial. Prespecified expected relationships between target PRO measures and relevant study variables were used to evaluate validity evidence. Additionally, MWPC thresholds were estimated using anchor- and distribution-based analyses.

Both PRO measures exhibited adequate internal consistency for clinical trial use. All examined correlations with reference variables and score differences between clinically meaningful groups conformed to expectations for both measures. Estimated thresholds for meaningful worsening were a decrease of 6–7 points on the PROMIS PF-SF and an increase of 2–3 points on NSCLC-SAQ.

This study is the first to examine longitudinal measurement properties of PROMIS PF-SF and investigates thresholds for meaningful change on the PROMIS PF-SF and NSCLC-SAQ measures. Results support the validity of these measures in NSCLC and aid the interpretation of clinically meaningful change in scores over time.