| Outcome | 36.9 | 51.9 |
| Individual variables | | |
| Age, yr | | |
| 12-15 | 65.8 | 66.0 |
| 16-17 | 34.2 | 34.0 |
| Ethnicity | | |
| White | 74.6 | 73.9 |
| Asian | 10.4 | 11.0 |
| Other | 8.6 | 8.6 |
| Unknown | 6.4 | 6.5 |
| Household education level | | |
| University | 33.0 | 33.2 |
| High school/college | 49.8 | 49.0 |
| Less than high school | 3.6 | 3.6 |
| Unknown | 13.7 | 14.2 |
| Body mass index | | |
| Normal weight | 68.0 | 65.7 |
| Underweight | 10.8 | 5.8 |
| Overweight | 10.7 | 17.3 |
| Obese | 2.8 | 5.4 |
| Unknown | 7.6 | 5.8 |
| Cycle and season | | |
| Cycle | | |
| 2003-2004 | 23.4 | 23.7 |
| 2005-2006 | 21.3 | 21.0 |
| 2007-2008 | 18.9 | 18.6 |
| 2009-2010 | 18.7 | 18.8 |
| 2011-2012 | 17.8 | 17.9 |
| Season | | |
| Summer | 34.4 | 34.2 |
| Winter | 18.2 | 18.4 |
| Transitional | 47.3 | 47.4 |
| Area-based variables | | |
| Metropolitan-influenced zone | | |
| Urban | 80.6 | 81.2 |
| Urban outskirt | 12.1 | 11.8 |
| Rural | 7.2 | 7.1 |
| Material deprivation quintile | | |
| Most privileged | 17.4 | 16.5 |
| Privileged | 22.5 | 23.3 |
| Median | 28.2 | 28.5 |
| Deprived | 21.2 | 21.1 |
| Most deprived | 10.8 | 10.5 |
| Social deprivation quintile | | |
| Most privileged | 12.9 | 12.6 |
| Privileged | 23.6 | 24.0 |
| Median | 27.7 | 27.2 |
| Deprived | 24.8 | 23.9 |
| Most deprived | 11.1 | 12.2 |