Non-enrolment of ovarian cancer patients in clinical trials: reasons and background. - Harter,P.; du Bois,A.; Schade-Brittinger,C.; Burges,A.; Wollschlaeger,K.; Gropp,M.; Schmalfeldt,B.; Huober,J.; Staehle,A.; Pfisterer,J. (Ann Oncol, 2005)