Table 2

Summary of hierarchical regression analysis for variables predicting residents’ self-reports of near misses (n=28)

Variable	Step 1			Step 2
Variable	β†	SE β	β‡	β†	SE β	β‡
Exercise	0.151	0.087	0.296	0.129	0.076	0.253
Preshift energy	−0.007	0.048	−0.024	0.021	0.043	0.073
Preshift stress	0.037	0.054	0.125	0.068	0.048	0.232
Expectation of stressfulness of shift	0.035	0.054	0.110	0.035	0.047	0.111
Work-related exhaustion	−0.010	0.004	−0.381*	−0.009	0.004	−0.371*
TNF-α	0.002	0	0.638***	0.002	0.001	0.612**
Critically ill patients				0.010	0.068	0.028
Patients with trauma				0.195	0.068	0.386*
R²	0.583			0.716
F for change in R²	4.884**			4.466*