An error occurred in table 1 of a paper published in the May 2007 issue (de Jager W, Hoppenreijs PAH, Wulffraat NM, Wedderburn LR, Kuis W, Prakken BJ. Blood and synovial fluid cytokine signatures in patients with juvenile idiopathic arthritis: a cross-sectional study. Ann Rheum Dis 2007;66:589–98). The correct table is available online at http://ard.bmj.com/contents/vol67/issue2.