Table 4 Comparison of weighted prevalence of short sleep duration by different characteristics
Characteristics | Prevalence (%)a | x2 | P value |
|---|---|---|---|
Age (y) | Â | 885.8b | <.0001 |
  ≤ 13 | 44.1 (40.9–47.3) |  |  |
 14–15 | 68.5 (65.7–71.3) |  |  |
  ≥ 16 | 72.5 (70.1–74.9) |  |  |
Sex | Â | 43.4c | <.0001 |
 Boys | 62.1 (59.9–64.4) |  |  |
 Girls | 69.8 (67.2–72.4) |  |  |
Areas | Â | 3.77c | 0.05 |
 Urban | 69.5 (66.0–73.1) |  |  |
 Rural | 64.2 (61.0–67.4) |  |  |
Types of school | Â | 158.5c | <.0001 |
 Middle school | 59.0 (55.8–62.2) |  |  |
 Academic high school | 82.4 (79.7–85.1) |  |  |
 Vocational high school | 59.7 (56.4–63.0) |  |  |