Effect of training on outcomes
Primary end point of mortality
Overall, there were 88 deaths in the exercise arm (median time to
event, 618 days) and 105 in the control arm (421 days). Mortality
was significantly lower in the exercise group (log rank 2 = 5.9,
P = 0.015). After verification of the Cox proportional hazards
assumption (2 = 3.1, P > 0.05), the hazard ratio for mortality was
computed to be 0.65 (95% confidence interval 0.46 to 0.92). The
survival curves are shown in figure 3. These results would imply
a number needed to treat of 17 to prevent one death in two years.