OBJECTIVES: To evaluate psychometric properties of the patient-reported PROMIS Fatigue-Short Form 7a (PROMIS F-SF 7a) in adults with newly diagnosed or recurrent MAC lung disease (MAC-LD).

METHODS: Data analyzed were from ARISE (NCT04677543; baseline and longitudinal data) and ENCORE (NCT04677569; baseline data) double-blind, randomized, active-control trials assessing impact of once-daily amikacin liposome inhalation suspension (ALIS) treatment on fatigue symptoms in MAC-LD. In ARISE, treatment was administered for 6 months, followed by 1 month off treatment. Modern psychometric methods (MPMs) were employed to test item properties and establish an empirical scoring algorithm. Classical measurement properties evaluated included reliability (internal consistency, test-retest reliability [TRTR]), convergent and known-groups validity, and responsiveness (meaningful within-patient change [MWPC]). MPMs, internal consistency (Cronbach’s alpha), convergent validity (Pearson correlations), and known-groups validity were analyzed at baseline (N=230 patients [ARISE: n=98, ENCORE: n=132]). Convergent validity was assessed between PROMIS F-SF 7a and the EXACT tool, E-RS scale, SGRQ, and FACIT-Fatigue. Known-groups validity compared PROMIS F-SF 7a scores across PGI-S Fatigue groups. TRTR was estimated via intraclass correlation coefficient (ICC[A,1]) among patients reporting no change in PGI-S Fatigue between screening and baseline. Anchor-based MWPC thresholds were estimated between baseline and end of study (month 7) and supplemented with empirical cumulative distribution curves (N=99 patients from ARISE).

RESULTS: MPMs supported relevance of all items and a sum score for the PROMIS F-SF 7a. The PROMIS F-SF 7a demonstrated strong internal consistency (Cronbach’s alpha: 0.86, 95% CI: 0.83–0.89), TRTR (ICC[A,1]: 0.76), and convergent validity (EXACT: 0.56, E-RS: 0.52, SGRQ: 0.66, FACIT-Fatigue: -0.80). Known-groups validity was demonstrated across PGI-S Fatigue groups. MWPC analyses supported a -4.00-point change from baseline as a proposed clinically meaningful within-patient improvement.

CONCLUSIONS: The findings demonstrate the PROMIS F-SF 7a has adequate reliability, validity, and responsiveness for assessing fatigue symptoms in adults with newly diagnosed or recurrent MAC-LD.