Etanercept in juvenile idiopathic arthritis: Who will benefit? by van den Berg JM, Swart JF, Dolman KM, Gorter SL, Koopman-Keemink Y, Twilt M, Hoppenreijs EPAH, ten Cate R, Armbrust W, Prince FHM, Otten MH, Wulffraat NM, van Rossum MAJ, van Suijlekom-Smit LWA