3.1. Conscientiousness cognitive ability interactions
In Step 2, the 95% confidence intervals excluded zero for Care-
fulness cognitive ability, Discipline cognitive ability, and glo-
bal conscientiousness cognitive ability, suggesting these
interaction terms have predictive power with regard to safety. An
examination of the change in Multiple R for each set of regressions
illustrates that inclusion of the interaction term results in a substantial
increase in predictive power over the additive terms alone,
13% for Carefulness cognitive ability (
DR = .04), 26% for Discipline
cognitive ability (
DR = .07), and 21% for global conscientiousness
cognitive ability (
DR = .06). Plots of these interactions
are presented in Figs. 1a, 1b, and 1c, respectively. The general pattern
is similar across interactions. These figures suggest that lower
levels of safety behavior were displayed by individuals with both
low cognitive ability and low conscientiousness. In contrast, those
with high levels of cognitive ability were found to display higher
safety behavior regardless of their level of facet or global conscientiousness.
As shown in Table 3, additional analyses (c.f. Perkins &
Corr, 2006) revealed that correlations between facet/factor-level
conscientiousness and safety were strong and positive
(r = .35.43) for participants with cognitive ability scores one SD
or more below the mean. However, for participants with cognitive
ability scores one SD or more above the mean, conscientiousness –
safety correlations were substantially weaker (r = .09.04), with
confidence intervals including zero.