Table 1 Characteristics of the 2,698 participants stratified by quartiles of hours of mobile phone use per week (weekdays and weekends)
Participants | Hours of mobile phone use per week | P for trenda | |||
|---|---|---|---|---|---|
Quartile 1: <10 h/week (N = 741) | Quartile 2: 10–18 h/week (N = 622) | Quartile 3: 19–32 h/week (N = 691) | Quartile 4: ≥33 h/week (N = 644) | ||
Females (%) | 49.4 | 63.7 | 64.4 | 74.5 | <0.001 |
First-year students (%) | 46.7 | 46.6 | 46.2 | 42.0 | 0.373 |
Participation in sports club (%) | 43.2 | 45.4 | 42.5 | 32.1 | <0.001 |
Mobile phone users since junior high school (%) | 34.5 | 44.3 | 51.4 | 60.0 | <0.001 |
Hours spent sleepingb | 6.3 (1.0) | 6.3 (0.9) | 6.2 (1.0) | 6.1 (1.0) | <0.001 |