Agreement between physicians and parents in rating functional ability of children with juvenile idiopathic arthritis

OBJECTIVE: To investigate concordance between physicians and parents in rating the degree of functional ability of children with juvenile idiopathic arthritis (JIA). METHODS: The attending physician and a parent were asked to rate independently the level of physical functioning of 155 patients with disease duration ≥ 5 years on a 6-point scale ranging from 1 = no disability (i.e. the child can do without difficulty all activities that children of his/her age can do) to 6 = severe disability (i.e. all activities are difficult for the child). At study visit, measures of JIA activity and damage were assessed. Agreement was evaluated with weighted kappa (<0.40 = poor agreement; 0.41–0.60 = moderate agreement; 0.61–0.80 = substantial agreement; >0.80 excellent agreement). Physician/parent evaluations were divided in 3 groups: 1) concordance; 2) parent over-rating = parent assessment over-rated relative to physician assessment; 3) physician over-rating = physician assessment over-rated relative to parent assessment. Factors affecting concordance/discordance were evaluated by means of Kruskal-Wallis or Chi-square/Fisher exact test. RESULTS: Concordance, parent over-rating and physician over-rating were observed in 107 (69%), 29 (18.7%) and 19 (12.3%) evaluations, respectively. Kappa value was 0.69. Parent over-rating was associated with greater intensity of pain (p = 0.01) and higher Childhood Health Assessment Questionnaire (C-HAQ) score (p = 0.004), whereas physician over-rating was associated with more severe joint disease (p = 0.04 to <0.001), higher C-reactive protein (p = 0.03) higher frequency of Steinbrocker functional class = II (p < 0.001), and greater articular damage, as measured with the Juvenile Arthritis Damage Index (p < 0.001). CONCLUSION: Physicians and parents revealed fair concordance in rating functional ability of children with JIA. Parent over-rating was associated with greater child's pain and worse C-HAQ score, whereas physician over-rating was associated with greater severity of joint inflammation and damage.