Characteristics | Mean (SD) or N (%) |
---|---|
Age | 19.90(1.34) |
Gender | |
 Male | 1,668(38.6) |
 Female | 2,657(61.4) |
Ethnicity | |
 Han | 1,743(40.3) |
 Tibetan | 2,582(59.7) |
HSS | |
 Good | 690(16.0) |
 Average | 2,296(53.1) |
 Poor | 1,339(30.9) |
School grade | |
 First year | 2,268(52.4) |
 Second year | 2,057(47.6) |
Smoking | |
 Yes | 551(12.7) |
 No | 3,774(87.3) |
Drinking | |
 Yes | 634(14.7) |
 No | 3,691(85.3) |