Table 1.

Demographic characteristics of the study population: secondary-school students (n 12 188) aged 12–17 years participating in the 2009–10 National Secondary Students’ Diet and Activity (NaSSDA) survey, Australia

	Frequency, n	Percentage
Sex
Male	6460	53·0
Female	5728	47·0
Year level
Year 8	3772	30·9
Year 9	3340	27·4
Year 10	2647	21·7
Year 11	2429	19·9
Socio-economic position
1st quintile (most disadvantaged)	1757	14·4
2nd quintile	2175	17·8
3rd quintile	2525	20·7
4th quintile	2537	20·8
5th quintile (least disadvantaged)	3194	26·2
Geographic location
Metropolitan	7841	64·3
Rural	4347	35·7

Figures based on unweighted data. Percentages may not sum to 100 % due to rounding.