Because reliable esti- mates of benefit, such as absolute risk reduction, are fre- quently unavailable for many specific subgroups, the risk for death can be estimated before treatment and the anticipated absolute risk reduction calculated (obtained by multiplying the RR reduction by the pretreatment risk). In the STICH (Surgical Treatment for Ischemic Heart Failure) trial, in which 1212 patients with an LVEF #35% and CAD amena- ble to revascularization were randomized to CABG or med- ical therapy, there was no significant difference in overall mortality rate, but during a median follow-up of 56 months, 28% of those assigned to CABG died of a cardiovascular cause, compared with 33% of those receiving medical ther- apy.410 This information can be converted to a more interpre- table framework, such as the average reduction in risk of events or number needed to treat. In this example, the average reduction in cardiovascular events was 19%, and it would be necessary to perform bypass surgery on about 5 patients with LV dysfunction to prevent 1 cardiovascular death at 5 years Fihn et al Stable Ischemic Heart Disease: Full Text e391 (ie, number needed to treat 5 5, calculated as 1 4 absolute risk reduction, or 1/0.19 [although there would be no effect on overall mortality rate]). This process complies with the Institute of Medicine s goals for transparently sharing evi- dence with patients so that they can control (or more actively participate in) their own decisions.411 In general, a beneficial effect of revascularization on survival has been demonstrated most clearly among patients with the highest cardiovascular risk.412 Although traditional methods of risk stratification have relied on coronary anatomy and LV function, other strategies described in this guideline can be used (Figure 5). 