Skip to main content

Table 1 Characteristics of the study population

From: The effect of long working hours on 10-year risk of coronary heart disease and stroke in the Korean population: the Korea National Health and Nutrition Examination Survey (KNHANES), 2007 to 2013

  Men Women
n % n %
Age (years)
 30–39 2475 32.7 1785 28.6
 40–49 2661 35.2 2249 36.1
 50–60 2429 32.1 2200 35.3
Education
 Below elementary school 546 7.2 1041 16.7
 Middle school graduate 771 10.2 872 14.0
 High school graduate 2802 37.0 2487 39.9
 Above college graduate 3446 45.6 1834 29.4
Income status
 1st Quartile 437 5.8 545 8.7
 2nd Quartile 1733 22.9 1573 25.2
 3rd Quartile 2518 33.3 1993 32.0
 4th Quartile 2877 38.0 2123 34.1
Employment condition
 Paid worker 4671 61.7 3836 61.5
 Self-employed or employer 2743 36.3 1547 24.8
 Unpaid family worker 151 2.0 851 13.7
Occupation
 Managers and professionals 1822 24.1 1298 20.8
 Office workers 1264 16.7 819 13.1
 Service and sales workers 1193 15.8 2025 32.5
 Agriculture, forestry, and fishery workers 576 7.6 553 8.9
 Craft, device, and machine operators and assembly workers 2188 28.9 411 6.6
 Manual workers 522 6.9 1128 18.1
Work shift
 Fixed-day schedule 6392 84.5 5144 82.5
 Any schedule other than fixed-day schedule* 1173 15.5 1090 17.5
Weekly working hours
  < 30 460 6.1 1357 21.8
 30–40 649 8.6 974 15.6
 40 1406 18.6 981 15.7
 40–50 1567 20.7 1085 17.4
 50–60 1587 21.0 757 12.1
 60–70 1009 13.3 488 7.8
 70–80 555 7.3 367 5.9
  ≥ 80 332 4.4 225 3.6
Total 7565 54.8 6234 45.2
  1. *Any schedule other than fixed-day schedule includes day-night shift, fixed night, regular rotation, 24-h shift, split shift, irregular shift, and another schedule