Reliability and validity of patient‐reported outcome instruments in US adults with hemophilia B and caregivers in the B‐HERO‐S study.

Objective: To assess the reliability and validity of six patient‐reported outcomes (PRO) instruments for evaluating health‐related quality of life in adults with mild‐severe hemophilia B and caregivers of children with hemophilia B, including affected women/girls. Methods: Adults with hemophilia B and caregivers completed separate online surveys containing several PRO instruments, which were administered to adult participants only (EQ‐5D‐5L, Brief Pain Inventory v2 Short Form, Hemophilia Activities List, and International Physical Activities Questionnaire), both adults and caregivers (Patient Health Questionnaire [PHQ‐9]), or caregivers only (Generalized Anxiety Disorder 7‐Item [GAD‐7] scale). Construct validity and item‐total correlation were assessed using Pearson product‐moment correlation, internal consistency was assessed using Cronbach's alpha coefficient, and known‐group validity was assessed by comparisons to self‐reported characteristics based on the Kruskal‐Wallis test. Results: Patient‐reported outcomes instruments generally showed satisfactory reliability for adults (n = 299) and caregivers (n = 150). In adults, PRO instruments generally showed high construct validity. Most PRO instruments showed expected significant differences among known groups for adults and caregivers. PHQ‐9 and GAD‐7 did not show significant differences among caregiver age groups. Conclusions: Patient‐reported outcomes instruments administered in B‐HERO‐S demonstrated reliability and validity in the broader population of adults with hemophilia B and caregivers when including all severities and genders. [ABSTRACT FROM AUTHOR]