Download I - PREDICTOR

5.3.2.4
Studying
the
Comparing dead and alive patients
discrimination
between these two groups of
outcomes for patients, we are
trying
to
compare
two
independent populations with
respect to a particular variable.
This variable will always be
numeric, or at least we will
treat it as such, so the statistical
functions that we will use will
be the ones listed in M.3.4.
Hypothesis testing (Appendix
M): T-test and Mann-Whitney
Test.
Figure 15 - I-PREDICTOR: Statistical tests Tab (Statistical screen)
5.3.3
Define a day
One of the main problems that we had during the implementation was to how define a ‘day’ in
the context of each patient’s stay in the ICU. The first option was to define a day in the normal
way, starting at 00:00h and ending at 23:59h on the same day. But is that the definition of a
patient’s day used by the
clinicians? If we consider a day
as a natural day, and we are
comparing
selecting
a
patients
by
specific
time
period (e.g. Day 2), we will
always be comparing different
time points of the patients'
stays
(unless
their
unit
admission time was at the
same time of day).
For
example,
two
considering
Figure 16 – I-PREDICTOR: Time Period Tab (Statistical screen), selecting days
50