The number of patients needed for each arm of the experiment was estimated assuming an absolute 2-year risk of treatment failure of 15% in the control arm. Assuming proportional hazards there is an absolute 2-year risk of failure in the peer-support group of 7%. Requiring a power of 80% and a significance level of 5% approximately 480 patients are required. In order to account for some losses to follow-up and deviations from our assumptions, we will recruit a total of 260 patients into each arm.