Table 1.

Descriptive characteristics of the study population at baseline measurement (May 1998) according to age group

Age groups	Total population (n = 7,734)	18–25 years (n = 187)	26–35 years (n = 1,665)	36–45 years (n = 2,925)	46–55 years (n = 2,548)	56–65 years (n = 409)	p value
Gender (%)
Male	72.2	48.1	56.6	71.5	83.0	85.1	<0.0001
Female	27.8	51.9	43.4	28.5	17.0	14.9
Educational level (%)
Low	22.9	9.6	13.2	21.2	30.3	35.2	<0.0001
Medium	30.1	38.5	33.2	30.7	27.5	25.4
High	47	51.9	53.6	48.1	42.1	39.4
Long-term illness (%)
Yes	21.5	12.8	15.9	19.2	27.8	25.5	<0.0001
No	78.5	87.2	84.1	80.8	72.2	74.5
Living situation alone (%)
Yes	10.3	18.8	14.4	9.3	8.2	9.5	<0.0001
No	89.7	81.2	85.6	90.7	91.8	90.5
Work–family conflict (%)
Yes	8.4	7.1	9.1	9.9	6.7	5.7	<0.0001
No	91.6	92.9	90.9	90.1	93.3	94.3
Working hours per week (%)
>40	25.6	16.7	21.8	24.3	30.2	25.8	<0.0001
36–40	54.6	65.1	53.7	53.5	55.6	54.1
26–35	8.1	9.1	8.6	9.4	6.3	7.9
16–25	10.3	7	14.5	11.5	6.6	9.8
<16	1.4	2.2	1.4	1.3	1.3	2.5
Overtime (%)
Yes	50.7	46.5	52.1	53.7	48.9	37.1	<0.0001
No	49.3	53.5	47.9	46.3	51.1	62.9
Psychological job demands (%)
Low	31.8	44.9	37.3	28.2	30.2	38.6	<0.0001
Medium	33.3	33.1	32.2	34.4	32.7	33.1
High	35	21.9	30.5	37.4	37.1	28.3
Decision latitude (%)
Low	28.3	29.3	29.4	27.3	28.4	30.6	0.556
Medium	34.7	37	33.3	35.1	34.9	36.3
High	36.9	33.7	37.4	37.6	36.7	33.1
Physically demanding work (%)
Yes	14.7	20.8	15.9	13.3	15.2	13.8	0.013
No	85.3	79.2	84.1	86.7	84.8	86.2
Smoking (%)
Yes	23	13.4	17.3	24.8	25.1	24.9	<0.0001
No	77	86.6	82.7	75.2	74.9	75.1