Table 5. Linear regression models for DQD, classified by predictor factor.

	DQD	Univariate Model		Final Multivariate Model
	Mean (SD)	Coef. (95% CI)	P-value	Coef. (95% CI)	P-value
Gender
Women	42.6 (9.7)	Reference		Reference
Men	44.0 (9.7)	1.45 (0.73; 2.18)	<0.001	2.40 (1.68; 3.09)	<0.001
Age groups
60–69	43.5 (9.8)	Reference
70 or over	42.9 (9.6)	-0.60 (-1.33; 0.14)	0.11
Marital Status
Married	42.9 (9.8)	Reference		Reference
Other marital status*	44.4 (9.5)	1.51 (0.67; 2.35)	<0.001	1.20 (0.42; 2.00)	<0.001
Work Status
No	41.9 (9.6)	Reference		Reference
Yes	46.8 (9.2)	4.89 (4.08; 5.70)	<0.001	1.09 (0.28; 1.89)	0.008
Education level
High	36.8 (9.2)	Reference		Reference
Illiteracy	45.5 (8.8)	8.73 (7.58; 9.88)	<0.001	5.22 (4.00; 6.44)	<0.001
Low	44.1 (9.6)	7.31 (6.21; 8.41)	<0.001	4.15 (3.07; 5.22)	<0.001
Medium	42.1 (9.8)	5.30 (3.99; 6.60)	<0.001	3.24 (2.04; 4.45)	<0.001
BMI
Obesity	42.5 (9.2)	Reference		Reference
Underweight	44.9 (8.8)	2.43 (0.67; 4.18)	0.007	-0.99 (-2.53; 0.54)	0.20
Normal	43.9 (9.7)	1.38 (0.07; 2.69)	0.04	-0.83 (-1.97; 0.30)	0.15
Overweight	42.0 (10.1)	-0.49 (-1.87; 0.89)	0.49	-1.30 (-2.48; -0.11)	0.03
Urbanicity levels
High	38.2 (9.3)	Reference		Reference
Low	49.1 (8.3)	10.9 (10.1; 11.7)	<0.001	8.93 (8.02; 9.84)	<0.001
Medium	42.4 (8.3)	4.21 (3.42; 5.01)	<0.001	2.76 (1.92; 3.59)	<0.001
Regions
Northeast	40.2 (10.7)	Reference		Reference
East Coast	41.7 (9.1)	1.41 (0.30; 2.52)	0.01	0.99 (-0.01; 1.98)	0.05
Central	46.2 (9.9)	5.96 (4.91; 7.02)	<0.001	4.35 (3.39; 5.31)	<0.001
West	43.2 (8.4)	2.97 (1.88; 4.06)	<0.001	0.32 (-0.70; 1.33)	0.54

*Other marital status includes divorced; widowed; separated and never married.