Table 2: Distribution of sociodemographic variables.

Sociodemographic
Variables		 GPS
(n = 256)		 DCS
(n = 249)		 Comparison
between both Samples
Chi-square test M-W U test
f % f % χ2 df p ZU p
Sex Woman 132 51.6 121 48.6 0.33 1 0.563 - -
Man 124 48.4 128 51.4
Age
groups*		 18 and 19 7 2.7 30 12.0 - - - -0.67
-0.59*		 0.503
0.555*
20 to 29 52 20.3 56 22.5
30 to 39 68 26.6 27 10.8
40 to 49 59 23.0 48 19.3
50 to 59 39 15.2 67 26.9
60 or more 31 12.1 21 8.4
Education
level		 Primary 14 5.5 20 8.0 - - - -1.70 0.089
Secondary 40 15.6 39 15.7
High School 41 16.0 56 22.5
Technical career 35 13.7 30 12.0
Bachelor degree 120 46.9 97 39.0
Postgraduate 6 2.3 7 2.8
Marital
status		 Single 78 30.5 103 41.4 8.70 4 0.069 - -
Married 147 57.4 127 51.0
Divorced 16 6.3 7 2.8
Widow 8 3.1 6 2.4
Living partner 7 2.7 6 2.4
Occupation Housewife 31 12.1 63 25.3 74.65 6 <0.001 - -
Laborer 18 7.0 12 4.8
Employee 158 61.7 80 32.1
Business owner 13 5.1 13 5.2
Student 14 5.5 66 26.5
Unemployed 2 0.8 4 1.6
Retiree 20 7.8 11 4.4
Subjective
socioeconomic
status		 Low 12 4.7 13 5.2 - - - -0.16 0.874
Medium-low 68 26.6 66 26.5
Medium-middle 156 60.9 151 60.6
Medium-high 20 7.8 19 7.6

GPS = General Population Sample. DCS = Dental Clinic Sample. * Comparison without grouping together the first and last categories of age.