Assessment of internal consistency reliability and concurrent validity of PROMIS® dyspnea characteristics v1.0, PROMIS® dyspnea functional limitations 10a, and PROMIS® global health v1.2 in a dysautonomia cohort

Background Dyspnea, or shortness of breath, is frequently reported among individuals with autonomic nervous system dysfunction, or dysautonomia. Currently, there are no validated dyspnea-specific patient-reported outcome measures for this population. Methodology We conducted a patient-reported outcomes study to evaluate the internal consistency, reliability, and concurrent criterion-related validity of three PROMIS ® instruments: Dyspnea Characteristics v1.0, Dyspnea Functional Limitations 10a, and Global Health v1.2 in a cohort of adult individuals with dysautonomia. These instruments assess the prevalence of dyspnea, general quality of life, and dyspnea-related functional limitations. Results Of the 617 participants enrolled in this study, 414 individuals without comorbid conditions causing dyspnea were included in the primary analysis. The PROMIS ® Dyspnea Characteristics v1.0 and PROMIS ® Dyspnea Functional Limitations 10a instruments demonstrated good to excellent internal consistency reliability (Cronbach’s alpha = 0.896-0.909; McDonald’s omega total = 0.911-0.912). The PROMIS ® Global Health v1.2 instrument demonstrated good overall internal consistency (Cronbach’s alpha = 0.846, McDonald’s omega total = 0.852), although reliability varied among the Global Physical Health and Global Mental Health summary scores (Cronbach’s alpha = 0.640-0.759; McDonald’s omega total = 0.664-0.767). Confirmatory factor analysis supported a unidimensional structure for both the PROMIS ® Dyspnea Characteristics v1.0 and Dyspnea Functional Limitations 10a instruments and a two-factor structure (Global Physical Health and Global Mental Health) for the Global Health v1.2 instrument. The indices demonstrated a good to excellent model fit (Comparative Fit Index = 0.983-1.00). Analyses demonstrated strong concurrent criterion-related validity for the PROMIS ® Dyspnea Functional Limitations 10a instrument (r = 0.59063) and weak-to-moderate concurrent validity for the Global Health v1.2 instrument (r = -0.17763 to -0.35034). Conclusion These findings support the use of the PROMIS ® Dyspnea Functional Limitations 10a and Global Health v1.2 instruments in clinical and research settings to assess symptom burden, functional limitations, and quality of life in adults with dysautonomia.