The primary endpoint by which the two strategies were compared was total mortality, analyzed by intention-to-treat. Secondary endpoints were composite end points (total mortality, disabling intracranial bleed, stroke, disabling anoxic encephalopathy, cardiac arrest, major noncentral nervous system bleed, cost of therapy, and quality of life. Follow-up was a minimum of two years and an average of 3.5 years. Recruitment and intervention extended from November 1995 through October 1999 with 4,060 patients enrolled by 213 sites.