From June 1980 to December 1982 164 patients with ovarian cancer stage III and IV were randomized into the three-legged Austrian Ovarian Cancer Study. A new polychemotherapy, known as the "changing-scheme" (adriamycin/cisplatinum--vincristine/cyclophosphamide--high dose methotrexate), developed in Vienna, was compared with adriamycin/cyclophosphamide and adriamycin/cisplatinum. The risk factors were stratified by means of special computer-assisted randomization. The first study evaluation in 1982 showed a significant advantage for the changing-scheme with regard to recurrence-free interval and survival (Mantel test: p less than 0.01, Breslow test: p less than 0.03). No difference was found between the combinations of adriamycin/cyclophosphamide and adriamycin/cisplatinum. At the second study evaluation in June 1984 the differences previously observed were no longe present to the same significant extent. The changing-scheme continued to be superior for the subgroups of patients with highly differentiated tumors, without ascites, with larger postoperative tumor burden and with liver metastases. The use of this therapy is be recommended for women with advanced ovarian cancer, especially in consideration of the much lower toxicity caused by the less frequent cisplatinum administrations as compared to the adriamycin/cisplatinum combination.