Validation of the EQ-5D-Y-5L parent-proxy version among children with juvenile idiopathic arthritis.

ABSTRACT

OBJECTIVES: Juvenile idiopathic arthritis (JIA) is the most common type of arthritis among children. It can cause joint pain and permanent physical damage, which affects mobility and daily activities. The EQ-5D-Y-3L self-report version has been validated in JIA, but the validity of EQ-5D-Y-5L remains unknown. We examined the psychometric properties of the EQ-5D-Y-5L parent-proxy version among children with JIA. METHODS: We used data from the Understanding Childhood Arthritis Network Canadian-Dutch collaboration study cohort, including patients with new-onset JIA, and those starting or stopping biologics. Clinical data and the parent-proxy version of the childhood health assessment questionnaire (CHAQ) and EQ-5D-Y-5L were collected. We evaluated the ceiling and floor effect; convergent and divergent validity using Spearman's rank correlation; known-group validity using one-way ANOVA (Analysis of Variance) and effect size; and informativity using Shannon's evenness index. RESULTS: 467 patient visits representing 407 patients were analyzed. The EQ-5D-Y-5L had no ceiling/floor effect. The EQ-5D-Y-5L showed good convergent (e.g., EQ-5D-Y-5L pain/discomfort dimension vs. CHAQ pain index (Spearman's r = 0.74, 95% confidence interval (C.I.) 0.69-0.79)), divergent (e.g., EQ-5D-Y-5L pain/discomfort dimension vs. CHAQ eating dimension (Spearman's r = 0.19, 95% C.I. 0.09-0.29)) and known-group validity (e.g., mean EQ-5D-Y-5L level summary score for patients with inactive versus active disease status, 6.34 vs. 10.52 (p < 0.001, effect size = 1.20 (95% C.I. 0.95-1.45)). Shannon's evenness index ranged from 0.52 to 0.88, suggesting most dimensions had relatively even distributions. CONCLUSIONS: In this patient sample, EQ-5D-Y-5L parent-proxy version exhibited construct validity and informativity, suggesting the EQ-5D-Y-5L can be used to measure the quality of life of children with JIA.

Juvenile idiopathic arthritis is the most common type of arthritis affecting children. It can cause pain and permanent physical damage to joints and affects mobility and daily activities. While there is no cure yet, new therapies like biologics are effective. However, biologics are expensive and can have side effects. To decide when is the best time to use these biologics, we need to understand their cost and impact on patients. EQ-5D-Y-5L is a common tool to measure how the disease affects a patient's life. It is unclear whether EQ-5D-Y-5L works well for patients with juvenile idiopathic arthritis. In this study, we compared the EQ-5D-Y-5L to another tool that measures how the illness impacts functional ability. We looked to see if the EQ-5D-Y-5L could tell the difference between children who were more or less sick. We also assessed whether the EQ-5D-Y-5L has the ability to describe patients with different severity in health status. This study indicates that the EQ-5D-Y-5L is a good tool to measure the health of patients with juvenile idiopathic arthritis. Findings from this study support the use of the EQ-5D-Y-5L among this patient population in future clinical trials and research studies.