There were ten possible variables in this
study with the results of the univariate tests.
The next step in securing a model was the
application of multivariate testing with
stepwise logistic regression. The univariate
results were informative but there was the
question of whether the association was a
direct association or whether there was a
joint correlation with a third variable. A
univariate test does not allow detection of
interaction effects which multivariate tests
may find. This study used model (1) with nine
variables (without Z scores) and model (2)
with ten variables, Z score included.