Development and validation of the european league against rheumatism response criteria for rheumatoid arthritis. Comparison with the preliminary american college of rheumatology and the world health organization/international league against rheumatism criteria - van Gestel, AM; Prevoo, ML; van’t Hof, MA; van Rijswijk, MH; van de Putte, LB; van Riel, PL (Arthritis Rheum, 1996)