Statistical Analysis
We estimated that the annual rate of the primary
end point would be 14.5% and the rate of death
from cardiovascular causes would be 7.0% in the
enalapril group. Calculation of the sample size was
based on mortality from cardiovascular causes. We
estimated that we would need to follow approximately
8000 patients for 34 months, with 1229
deaths from cardiovascular causes, to provide
the study with a power of 80% to detect a relative
reduction of 15% in the risk of death from cardiovascular
causes in the LCZ696 group, at an
overall two-sided alpha level of 0.05. On the basis
of these calculations, we estimated that the primary
end point would occur in 2410 patients,
which would provide a power of 97% to detect a
15% reduction in the risk of this outcome.
The data and safety monitoring committee