Functional Assessment Scores Not Interchangeable in Adolescents With Juvenile Idiopathic Arthritis

The scores from 3 health assessment questionnaires used in adolescents with juvenile idiopathic arthritis (JIA) were found to be not fully interchangeable, according to results from a study published in Arthritis Care & Research.

The researchers studied a group of 107 adolescents (or their proxies), using data from the Childhood Arthritis Prospective Study (CAPS) in the United Kingdom. Study participants self- or proxy-completed 1 of 3 assessment questionnaires of functional ability used in JIA, which included the proxy-completed Childhood Health Assessment Questionnaire (P-CHAQ), the adult HAQ, and the adolescent-specific CHAQ (A-CHAQ). Agreement and ability of the instruments to equivalently classify clinical changes in adolescents over time were evaluated.

After analysis, the researchers found that scores from the 3 tools exhibited strong associations (r>0.8), but were not fully interchangeable, with agreement rates varying from 70% to 80%. In addition, they reported that the HAQ and A-CHAQ questionnaires equivalently classified 80% to 90% of participants as having improved or worsened with respect to function.

One key limitation of the study was the lack of comparison between adolescents with severe disability.

“Whilst there is relatively high agreement and similar classification of change between HAQ and two CHAQ scores, these are not completely interchangeable,” the researchers wrote.

“The absolute values of the scores are therefore not directly comparable as adolescents move from [pediatric] to adult practice,” they concluded.

Reference

Shoop-Worrall SJW, Hyrich KL, Verstappen SM, et al. Comparing proxy, adolescent and adult assessments of functional ability in adolescents with juvenile idiopathic arthritis [published online March 15, 2019]. Arthritis Care Res. doi:10.1002/acr.23877