Deterministic Cost Analysis
The iv PPI strategy resulted in an expected cost per
subject of $4240, while the expected cost per subject for the standard treatment without iv PPI was
$5160. Therefore, early administration of iv PPI to
all subjects presenting to the ED generated expected
savings of $920 per subject. That strategy would
also have prevented 40 recurrent bleeds, 16 for iv
PPI versus 56 for no iv PPI; 9 surgical procedures, 5
for iv PPI versus 14 for no iv PPI; and 223 hospital
days, 1176 for iv PPI vs. 1398 for no iv PPI, per
1000 subjects.
One-Way Sensitivity Analyses
The results of the sensitivity analysis showed that
use of iv PPI would be cost-saving under a wide
range of scenarios, confirming that the finding was
robust (Fig. 2). The largest impact on the incremental cost, an 85% reduction in incremental savings,
originated from changes in the relative risk of a first
rebleed. However, even when a value corresponding
to a very small therapeutic benefit of iv PPI was
used, the incremental cost per subject still yielded
savings of $140 per subject.
Following the one-way sensitivity analyses, the
result that iv PPI prevented bleeding recurrences
was also robust to changes in values assigned to the
parameters of the model. This held even when considering extreme values for each of the variables
being tested.