Table 1 Sample characteristics and their associations with baseline response

 Male

5733

44.06

7108

44.93

1.00

 Female

7279

55.94

8669

54.79

1.04

0.99–1.09

0.091

 Missing data

0

0

44

0.28

Age in years, mean (SD)

41.91 (10.20)

40.43 (11.19)

 <30

1725

13.26

3228

20.40

1.00

 30–39

3791

29.13

4397

27.79

1.61

1.50–1.74

<0.001*

 40–49

4078

31.34

4222

26.69

1.81

1.68–1.94

<0.001*

 50–62

3418

26.27

3974

25.12

1.61

1.49–1.73

<0.001*

 Legislators, senior officials, and managers

1120

8.61

580

3.67

1.83

1.65–2.03

<0.001*

 Professionals

3662

28.14

2837

17.93

1.25

1.18–1.32

<0.001*

 Technicians and associate professionals

3641

27.98

3336

21.09

0.99

0.94–1.05

0.797

 Clerks

728

5.59

527

3.33

1.28

1.14–1.43

<0.001*

 Service workers and shop and market sales workers

2940

22.59

3626

22.92

0.66

0.63–0.70

<0.001*

 Skilled agricultural and fishery workers

1

< 0.01

7

0.04

0.13

0.02–1.06

0.056

 Craft and related trades workers

394

3.03

394

2.49

0.91

0.79–1.05

0.186

 Plant and machine operators and assemblers

44

0.34

95

0.60

0.42

0.29–0.60

<0.001*

 Elementary occupations

322

2.47

312

1.97

0.94

0.81–1.10

0.435

 Armed forces and unspecified

0

0

1

<0.01

-

-

 Missing data

160

1.23

4106

25.95

 Competence equivalent to minimum 4 years of higher education (>15 years)

3675

28.24

2848

18.00

1.00

 Competence equivalent to 1–3 years of higher education (13–15 years)

3683

28.30

3373

21.32

0.85

0.79–0.91

<0.001*

 Competence equivalent to high school (10–12 years)

4150

31.89

4713

29.79

0.68

0.64–0.73

<0.001*

 Occupations that do not require high school (<10 years)

336

2.58

324

2.05

0.80

0.69–0.94

0.008*

 Occupations with unspecified requirements for competence

1120

8.61

581

3.67

1.49

1.34–1.67

<0.001*

 Missing data

48

0.37

3982

25.17