Table 2 Characteristics of adolescents from Zhejiang by sleep duration
Characteristics | Total | Non-short | Short | P value |
|---|---|---|---|---|
| Â | sleep duration | sleep duration | ||
(N = 18,403) | (N = 6184) | (N = 12,219) | ||
Age (years) | 15.9 ± 1.8 | 15.8 ± 1.8 | 15.9 ± 1.8 | 0.33 |
Girls (%) | 9259 (49.7) | 2774 (44.1) | 6485 (52.7) | <.0001 |
Urban (%) | 7314 (33.1) | 2133 (29.6) | 5181 (34.9) | 0.05 |
Types of school (%) | Â | Â | Â | <.0001 |
 Middle school | 8834 (47.7) | 3651 (57.4) | 5183 (42.6) |  |
 Academic high school | 5597 (29.0) | 922 (15.0) | 4675 (36.3) |  |
 Vocational high school | 3972 (23.3) | 1611 (27.6) | 2361 (21.1) |  |
Paternal education level (%) | Â | Â | Â | <.0001 |
 High school or below | 10,525 (81.5) | 5046 (82.3) | 9636 (81.0) |  |
 College or above | 6787 (12.2) | 684 (9.7) | 1946 (13.6) |  |
 Unknown | 1091 (6.3) | 454 (8.0) | 637 (5.4) |  |
Maternal education level (%) | Â | Â | Â | <.0001 |
 High school or below | 11,352 (82.7) | 5054 (82.4) | 9875 (82.9) |  |
 College or above | 5880 (10.7) | 619 (9.0) | 1684 (11.6) |  |
 Unknown | 1171 (6.6) | 511 (8.6) | 660 (5.5) |  |
Physically active daily (%) | 3090 (16.6) | 1230 (19.4) | 1860 (15.1) | <.0001 |
Screen duration ≥2 h per day (%) | 3462 (19.2) | 1521 (24.2) | 1941 (16.6) | <.0001 |
Consuming breakfast daily (%) | 13,036 (70.9) | 4587 (74.0) | 8449 (69.4) | <.0001 |
Consuming fruits daily (%) | 13,170 (71.5) | 4648 (74.7) | 8522 (69.8) | <.0001 |
Consuming vegetables ≥2 times daily (%) | 13,746 (74.7) | 4559 (73.6) | 9187 (75.3) | 0.08 |
Consuming milk ≥3 days weekly (%) | 12,211 (66.9) | 4164 (67.9) | 8047 (66.3) | 0.07 |
Consuming carbonated drinks ≥4 times weekly (%) | 2389 (12.7) | 779 (12.2) | 1610 (12.9) | 0.35 |
Current cigarette smoking (%) | 992 (5.5) | 371 (5.9) | 621 (5.3) | 0.29 |
Current alcohol drinking (%) | 4311 (23.6) | 1400 (23.1) | 2911 (23.8) | 0.57 |
Often/always feel lonely (%) | 2055 (11.2) | 447 (7.4) | 1608 (13.2) | <.0001 |
Height (cm) | 166.2 ± 8.5 | 165.6 ± 8.8 | 166.5 ± 8.3 | <.0001 |
Weight (kg) | 54.6 ± 11.1 | 53.7 ± 11.5 | 55.0 ± 10.8 | <.0001 |
BMI (kg/m2) | 19.7 ± 3.3 | 19.5 ± 3.5 | 19.8 ± 3.1 | <.0001 |
Sleep duration (hours) | 8.3 ± 1.6 | 9.7 ± 1.0 | 7.6 ± 0.8 | <.0001 |