Table 2.

Results of categorical regression analysis

Explanatory variable	Scale (number of categories)	Coefficient		p	Pratt’s relative importance
		β	SE
Size	Ordinal (5)	0.427	0.131	0.000	0.43
Material	Nominal (6)	0.441	0.102	0.000	0.49
Animal species	Nominal (4)	0.204	0.103	0.011	−0.05
Route of exposure	Nominal (3)	0.258	0.093	0.001	0.14

β standardized partial regression coefficient