Smoking increases risk of tooth loss: A meta-analysis of the literature

Table 2 Source of heterogeneity by meta-regression analysis

Factors	Univariate			Multivariate
	Coefficient	SE	P value	Coefficient	SE	P value
Published year	-0.0063553	0.01429	0.661	-	-	-
Country (vs United States)
Japan	-0.0922341	0.11903	0.447	-	-	-
Finland, Norway, Sweden	0.1485642	0.14826	0.328	-	-	-
Other countries	0.1828302	0.12939	0.173	-	-	-
Study design (cohort vs cross-sectional)	0.0667818	0.12342	0.594	-	-	-
Base Population of Study (general population vs others)	-0.0761659	0.10297	0.467
Sex (male vs female)
Male	0.0739773	0.11212	0.517	-	-	-
Female	-0.1176073	0.24732	0.639	-	-	-
Mean age of study population	0.0080805	0.00284	0.009	0.0067276	0.00288	0.030
Adjustment for socioeconomic status (Yes vs No)	-0.0723939	0.10375	0.493	-	-	-
Adjustment for behavior associated with oral health (Yes vs No)	-0.0054823	0.10733	0.960	-	-	-
Definition number of tooth loss in the study (range: 1-28)	0.0093892	0.00430	0.040	0.0065434	0.00414	0.129