 The Surgical Treatments Outcomes Project for Dysfunctional Uterine Bleeding STOP-DUB is a multicenter, randomized clinical trial that assessed the efficacy and effectiveness of hysterectomy versus endometrial ablation EA for dysfunctional uterine bleeding DUB in women for whom medical management has not provided relief. Institutional review board-approved study sites included the coordinating center, chairs office, the American College of Obstetricians and Gynecologists, and 33 clinical centers in the United States and Canada. STOP-DUB enrolled 1 237 eligible patients for whom medical treatment had not been successful and who were randomized to either hysterectomy or EA; and 2 an observational cohort of 139 patients who were provisionally ineligible or who were eligible but did not wish to be randomized. Enrollment began November 25, 1997 and ended June 30, 2001. Randomized women were followed using telephone interviews at least 2 years and observational women were followed a maximum of 6 months. We also collected information on return clinical center visits and hospital bills from the sites directly. The primary outcome addressed by the randomized trial is the impact of surgery on bleeding, pain, fatigue, and the major problem symptom that led the woman to seek treatment for her condition, measured 1 year following surgery. Additional outcomes included the impact of surgery at time points after 1 year; changes in quality of life, activity limitation, sexual functioning, and urinary incontinence; surgical complications; additional surgery; and resource utilization. The costs and the relative cost-effectiveness of the two surgeries will be calculated. The main scientific objective for the observational study was to examine changes over time in terms of treatment selected, DUB-related symptoms, and quality of life. Enrolled women signed an informed consent to participate. 