Neuropsychological effects of interferon beta-1a in relapsing multiple sclerosis. Multiple Sclerosis Collaborative Research Group - Fischer, JS; Priore, RL; Jacobs, LD; Cookfair, DL; Rudick, RA; Herndon, RM; Richert, JR; Salazar, AM; Goodkin, DE; Granger, CV; Simon, JH; Grafman, JH; Lezak, MD; O’Reilly Hovey, KM; Perkins, KK; Barilla-Clark, D; Schacter, M; Shucard, DW; Davidson, AL; Wende, KE; Bourdette, DN; Kooijmans-Coutinho, MF (Ann Neurol, 2000)