. 2007 Jun 12;7:109. doi: 10.1186/1471-2458-7-109

Table 3.

Regression models assessing the association between independent variables and antitetanus toxin levels* in pre-vaccination sera of Group A and Group B women – p values

Independent variable	Group A^a(n = 22)		Group B^b(n = 66)

	Univariate analysis	Final model	Univariate analysis	Final model
Age in years	0.506	-	<0.001	-
Age at first tetanus toxoid	0.132	-	<0.001	<0.001
N.° doses of tetanus toxoid	0.002	0.022	0.376	-
Years since last tetanus toxoid^c	0.001	0.016	0.007	0.041
Age at last tetanus toxoid	0.007	-	0.002	-
R²	-	0.56	-	0.32

* Log transformation of values in mIU/ml

a: Group A = women who began vaccination with DPT/DT

b: Group B = women who began vaccination with TT

c: This variable was log transformed to be used in the models