Developing a disease activity tool for systemic-onset juvenile idiopathic arthritis by international consensus using the Delphi approach

OBJECTIVES: The systemic form of juvenile idiopathic arthritis may present with many diverse symptoms, signs and laboratory abnormalities. Our aim was to elicit and pool items useful for developing a consensus disease activity measure for systemic arthritis in children, using an international pool of respondents. METHODS: We used a Delphi survey process in two steps. First we surveyed 187 paediatric rheumatologists and allied health professionals. We elicited 2607 items that, when combined with previously elicited items from parents/patients, could be pooled into 107 independent items. We then surveyed the paediatric rheumatologists to determine the frequency and importance of the 107 items. RESULTS: Our response rate was 83% to both surveys. We identified 29 items as being the most important and most frequently seen indicators of active disease. The most highly rated of these items were: presence of fever, presence of rash, elevated ESR, elevated CRP, requirement for increasing medications, abnormal physician global evaluation and presence of joints with active arthritis. CONCLUSIONS: Twenty-nine items are thought by medical practitioners to be most relevant in determining disease activity in systemic arthritis. As a next step, the measurement properties of these items will be tested to help develop a disease activity tool.