A, Limb salvage and (B) amputation-free 3-year survival are shown for the femoral-popliteal bypass and primary superficial femoral artery (SFA) stent groups in patients with critical limb ischemia (CLI). For limb salvage after femoral-popliteal bypass, number at risk was 82 at the start and 22 at 3 years, and the standard error was .088. For amputation-free survival, the number was 82 at risk to start and 24 at 3 years, and the the standard error was 0.097. For limb salvage after primary SFA intervention, the number at risk was 103 at the start and 35 at 3 years was 35. The standard error was 0.088 at 3 years. For amputation-free survival, the number at risk was 103 to start and 37 at 3 years. The standard error was 0.089 at 3 years. CI, Confidence interval.