Table 1 Personal characteristics and characteristics of online behaviors of the study population of 5,122 Shanghai adolescents
Variables | N | Percentage (%) | Internet use %(Nusing internet/ Nwhole)c | Total Scorea(mean ± SD) | Internet addictionb%(Ninternet addiction/ Nwhole)d |
|---|---|---|---|---|---|
Gender (missing n=8) | |||||
 Female (ref.) | 2580 | 50.4% | 95.1% (2453 / 2580) | 117.0 ± 38.1 | 6.4% (164 / 2580) |
 Male | 2534 | 49.6% | 92.6% (2347 / 2534)**e | 122.4 ± 43.5***e | 11.3% (285 / 2534)***e |
Grade (missing n=1) | |||||
 Junior high school students (ref.) | 1915 | 37.4% | 92.6% (1774 / 1915) | 110.3 ± 42.4 | 7.1% (135 / 1915) |
 Senior high school students | 3206 | 62.6% | 94.6% (3033 / 3206)** | 125.3 ± 39.0*** | 9.8% (315 / 3206)** |
School type (missing n=2) | |||||
 Junior high school (ref.) | 1907 | 37.2% | 92.7% (1768 / 1907) | 110.4 ± 42.3 | 7.1% (135 / 1907) |
 Key senior high school | 1096 | 21.4% | 94.5% (1036 / 1096) | 120.2 ± 37.7*** | 6.1% (67 / 1096) |
 Ordinary senior high school | 1102 | 21.5% | 93.3% (1028 / 1102) | 122.9 ± 40.9*** | 9.4% (104 / 1102)* |
 Vocational senior high school | 1015 | 19.8% | 96.0% (974 / 1015)* | 133.1 ± 37.3*** | 14.2% (144 / 1015)*** |
Adolescent monthly money spending (missing n=9) | |||||
 < 100 RMB (ref.) | 3028 | 59.1% | 92.6% (2805 / 3028) | 112.2 ± 41.1 | 5.6% (168 / 3028) |
 100~300 RMB | 1373 | 26.8% | 95.7% (1314 / 1373)*** | 128.9 ± 38.0*** | 12.5% (172 / 1373)*** |
 ≥300 RMB | 712 | 13.9% | 95.7% (681 / 712)*** | 133.5 ± 38.3*** | 15.3% (109 / 712)*** |
Residential or commuter students (missing n=4) | |||||
 Commuter students (ref.) | 4667 | 91.1% | 93.7% (4372 / 4667) | 119.2 ± 41.3 | 8.7% (407 / 4667) |
 Residential students | 451 | 8.8% | 96.0% (433 / 451)* | 125.2 ± 35.6** | 9.5% (43 / 451) |
Academic achievement (missing n=16) | |||||
 Very good (ref.) | 324 | 6.3% | 92.3% (299 / 324) | 113.1 ± 42.2 | 4.0% (13 / 324) |
 Relatively good | 1386 | 27.1% | 94.4% (1308 / 1386) | 112.9 ± 38.3 | 5.6% (78 / 1386) |
 General | 2835 | 55.4% | 94.6% (2682 / 2835) | 122.3 ± 39.4*** | 8.9% (253 / 2835)*** |
 Relatively &very bad | 561 | 11.0% | 89.7% (503 / 561) | 126.8 ± 50.7*** | 18.9% (106 / 561)*** |
Main purpose of using internet (missing n=15) | |||||
 Academic learning (ref.) | 720 | 14.1% | 100% | 109.3 ± 26.8 | 1.4% (10 / 720) |
 Only browsing news or emails | 881 | 17.2% | 100% | 117.3 ± 25.7*** | 2.5% (22 / 881) |
 Playing games | 1003 | 19.6% | 100% | 140.7 ± 28.6*** | 20.1% (202 / 1003)*** |
 Real-time chatting | 667 | 13.0% | 100% | 132.5 ± 24.6*** | 8.1% (54 / 667)*** |
 Wandering aimlessly online | 1546 | 30.2% | 100% | 128.9 ± 29.2*** | 10.2% (158 / 1546)*** |
Place of using internet (missing n=24) | |||||
 School (ref.) | 314 | 6.1% | 100% | 115.2 ± 29.4 | 4.5% (14 / 314) |
 Residences of classmates or relatives | 705 | 13.8% | 100% | 120.7 ± 27.6* | 5.4% (38 / 705) |
 Home | 3586 | 70.0% | 100% | 128.5 ± 29.4*** | 10.3% (369 / 3586)** |
 Internet bar | 203 | 4.0% | 100% | 137.6 ± 25.9*** | 14.3% (29 / 203)*** |
Total hours online for a whole week (missing n=16) | |||||
 <7 hours (ref.) | 2812 | 54.9% | 100% | 117.7 ± 27.7 | 4.1% (114 / 2812) |
 7~14 hours | 970 | 18.9% | 100% | 133.2 ± 26.6*** | 11.8% (114 / 970)*** |
 14~21 hours | 414 | 8.1% | 100% | 140.9 ± 24.1*** | 15.5% (64 / 414)*** |
 21~28 hours | 242 | 4.7% | 100% | 145.8 ± 23.9*** | 22.3% (54 / 242)*** |
 >28 hours | 378 | 7.4% | 100% | 151.1 ± 26.9*** | 27.3% (103 / 378)*** |
Hours online per weekday (missing n=21) | |||||
 ≤2 hours (ref.) | 3390 | 70.5% | 100% | 121.9 ± 29.1 | 6.9%(235/3390) |
 2~4 hours | 756 | 15.7% | 100% | 134.3 ± 24.8*** | 10.6%(80/756)** |
 4~6 hours | 357 | 7.4% | 100% | 139.5 ± 26.9*** | 17.1%(61/357)*** |
 6~8 hours | 113 | 2.3% | 100% | 143.0 ± 28.0*** | 23.0%(26/113)*** |
 ≥8 hours | 195 | 4.0% | 100% | 151.4 ± 26.7*** | 24.2%(47/195)*** |
Hours online on each Saturday/Sunday (missing n=17) | |||||
 ≤2 hours (ref.) | 1835 | 35.8% | 100% | 114.5 ± 28.1 | 3.4% (63 / 1835) |
 2~4 hours | 1457 | 28.5% | 100% | 125.6 ± 25.8*** | 6.3% (92 / 1457)*** |
 4~6 hours | 668 | 13.0% | 100% | 136.5 ± 25.2*** | 12.0% (80 / 668)*** |
 6~8 hours | 351 | 6.9% | 100% | 143.8 ± 24.5*** | 20.2% (71 / 351)*** |
 ≥8 hours | 504 | 9.8% | 100% | 150.7 ± 27.5*** | 28.4% (143 / 504)*** |