Table 6.

Regression coefficients from models of OHIP scale scores

	Model 1	Model 2	Model 3	Model 4
Variables
Number of teeth	**-0.19	**-0.19	**-0.18	**-0.18
Card holder (ref. No card)	**2.58	**1.99	**1.81	**1.64
Relief of pain visit (ref. not relief of pain)	**2.05	**1.74	**1.81	**1.69
Positive affect	-	**-0.17	-	**-0.09
Negative affect	-	-	**0.21	**0.17
Model statistics
P value	<0.0001	<0.0001	<0.0001	<0.0001
R-sq	0.2022	0.2489	0.2757	0.2862
R-sq change
(model 2 vs model 1)	-	**0.0467	-	-
(model 3 vs model 1)	-	-	**0.0735	-
(model 4 vs model 2)	-	-	-	**0.0373
(model 4 vs model 3)	-	-	-	**0.0105

**(P < 0.01)