Table 1.

Demographic characteristics of participants.

	Overall (N = 4,658)	%
Age(years)
10–14	2937	63.1
15–19	1721	36.9
Nationally
Han	4537	99.3
Minorities	31	0.7
Residence
Rural	2292	49.8
Urban	2366	50.2
Level of education
Primary school	1696	36.4
Junior high school and above	2962	63.6
Living arrangement
Living with parents	3619	77.7
Living in a dormitory	602	12.9
Living with grandparents/relatives	420	9.0
Living with others	17	0.4