Comparing the Measurement Properties and Preferability of Patient-reported Outcome Measures in Pediatric Rheumatology: PROMIS vs CHAQ

Objective. The Childhood Health Assessment Questionnaire (CHAQ), though widely used for assessments in pediatric rheumatology, has drawbacks, including low correlation to disease activity and ceiling effects. We sought to determine if any tools from the Patient Reported Outcomes Measurement Information System (PROMIS) improve on these shortcomings and/or are preferred by patients. Methods. Patients 5-17 years of age with juvenile idiopathic arthritis (JIA) or juvenile dermatomyositis (JDM) were recruited from the rheumatology clinics at a Canadian children's hospital. Participants completed the CHAQ, 3 PROMIS measures (pain interference, mobility, and physical activity), and underwent a standard clinical assessment. Results. Fifty-two patients participated, 25 with JIA and 27 with JDM. None of the PROMIS measures suffered from ceiling effects, whereas the CHAQ Disability Index (DI) and pain visual analog scales both did, with 50% and 20% of patients achieving the best possible scores, respectively. The PROMIS mobility was moderately correlated to the CHAQ-DI (r(s) -0.60, 95% CI -0.75 to -0.40), and the PROMIS pain interference was strongly correlated to the CHAQ pain score (r(s) 0.65, 95% CI 0.43-0.80). No measures correlated with disease activity. Patients preferred the PROMIS to the CHAQ. Conclusion. The PROMIS pain interference, mobility, and physical activity measures improve in some areas where the CHAQ is weak: they do not suffer from ceiling effects, and patients prefer the PROMIS tools. More work is needed to determine the correlation and responsiveness of the PROMIS tools to changes in disease activity over time before they should be widely adopted for clinical use.