Trends in current smoking prevalence in various subgroups of Korean school-aged children and adolescents from 2008 to 2011
| Current smoking prevalence, % (CI) | p for trend (2008–2011) | p for trend § (2008–2010) | ||||
| 2008 n*=902 n†=4 715 528 | 2009‡ n*=617 n†=2 896 674 | 2010 n*=340 n†=5 227 550 | 2011 n*=338 n†=5 679 730 | |||
| Total | 12.6 (9.6 to 15.6) | 9.6 (6.6 to 12.5) | 8.1 (4.6 to 11.7) | 15.7 (10.5 to 20.9) | 0.353 | 0.081 |
| Age (years) | ||||||
| 10–12 | 1.4 (0.2 to 2.7) | 0 | 0 | 0 | – | – |
| 13–15 | 11.9 (6.3 to 17.4) | 10.6 (5.8 to 15.5) | 6.5 (1.2 to 11.9) | 14.3 (6.6 to 21.9) | 0.753 | 0.191 |
| 16–18 | 25.0 (18.8 to 31.3) | 17.5 (10.4 to 24.6) | 17.1 (8.7 to 25.5) | 29.4 (18.9 to 39.9) | 0.477 | 0.166 |
| Sex | ||||||
| Male | 16.5 (12.2 to 20.8) | 13.4 (9.3 to 17.6) | 13.6 (7.0 to 20.2) | 20.8 (13.0 to 28.5) | 0.335 | 0.495 |
| Female | 7.3 (4.3 to 10.4) | 4.2 (1.2 to 7.2) | 1.4 (0.0 to 3.1) | 9.1 (2.6 to 15.6) | 0.773 | 0.003 |
| Residence area | ||||||
| Seoul | 10.9 (4.6 to 17.3) | 6.1 (1.1 to 11.0) | 10.1 (1.7 to 18.4) | 6.3 (0.1 to 12.5) | 0.442 | 0.823 |
| Other cities | 12.8 (9.0 to 16.6) | 10.2 (6.7 to 13.7) | 6.6 (2.8 to 10.3) | 18.0 (11.1 to 25.0) | 0.280 | 0.034 |
| Rural area | 13.8 (6.6 to 21.0) | 13.3 (1.9 to 24.7) | 11.8 (1.1 to 22.5) | 19.9 (6.3 to 33.5) | 0.490 | 0.764 |
| Monthly household income¶ | ||||||
| Low (<120%) | 16.3 (10.4 to 22.2) | 15.4 (6.4 to 24.4) | 8.9 (0.0 to 17.8) | 23.7 (8.1 to 39.3) | 0.586 | 0.231 |
| Middle (120–250%) | 12.8 (7.7 to 17.9) | 9.1 (4.5 to 13.8) | 7.3 (1.0 to 13.6) | 17.3 (8.2 to 26.3) | 0.477 | 0.225 |
| High (≥250%) | 9.6 (4.9 to 14.2) | 7.3 (3.6 to 11.1) | 8.6 (2.9 to 14.2) | 11.6 (5.2 to 18.1) | 0.507 | 0.827 |
Data are presented as proportion (95% CI).
*Participants in the KNHANES IV, V.
†Estimated Korean population weighted by year.
‡The cotinine levels in 2009 were obtained in a half sample of participants.
§The values were obtained from 2008 to 2010, excluding the period effect in 2011.
¶Calculated based on the minimum cost of living (MCL) as measured by the government. MCL reflects family size and inflation each year.