DEVELOPMENT OF VALIDATED DISEASE-ACTIVITY AND DAMAGE INDEXES FOR THE JUVENILE IDIOPATHIC INFLAMMATORY MYOPATHIES .1. PHYSICIAN, PARENT, ANDPATIENT GLOBAL ASSESSMENTS

Objective. To determine the reliability, content validity, and respons iveness of physician global assessments of disease activity and damage in the juvenite idiopathic inflammatory myopathies (IIM), and to inve stigate concordance among physician, parent, and patient global rating s. Methods. Sixteen pediatric rheumatologists rated 10 juvenile IIM pa per patient cases far global disease activity and damage, and assessed the importance of 51 clinical and laboratory parameters in formulatin g their global assessments, Then, 117 juvenile IIM patients were enrol led in a protocol to examine the relationship between Likert and visua l analog scale global assessments, their sensitivity to change, and th e comparability of physician, parent, and patient global ratings. Resu lts. Pediatric rheumatologists demonstrated excellent interrater relia bility in their global assessments of juvenile IIM disease activity an d damage (97.7% and 94.7% agreement among raters, respectively), and a greed on a core set of clinical parameters in formulating their judgme nts. Likert scale ratings correlated with those on a visual analog sca le, and both were comparable in responsiveness (standardized response means -0.56 for disease activity, 0.02 [Likert] and 0.14 [visual analo g] for damage, measured over 8 months). Parent global ratings of disea se activity correlated with physician assessments, but were not coline ar (Spearman's correlation [r] = 0.41-0.45). Patient global disease ac tivity assessments correlated with those done by parents (r = 0.57-0.8 4) and physicians (r = 0.37-0.63), but demonstrated less responsivenes s (standardized response means -0.21 and -0.12, respectively, over 8 m onths). Conclusion. Physician global assessments of juvenile IIM disea se activity and damage demonstrated high interrater reliability and we re shown to be comprehensive measures. Both physician and parent disea se activity assessments should be considered valuable as quantitative measures for evaluating therapeutic responses in juvenile IIM patients .