Table 1 Basic gender differences in characteristics of the study participants [n (%)]
|  | Total (N = 1441) | Male (n = 696) | Female (n = 745) | p |
|---|---|---|---|---|
Age (years) | ||||
 ≤ 19 | 664 (46.1) | 306 (44.0) | 358 (48.1) | .120 |
 ≥ 20 | 777 (53.9) | 390 (56.0) | 387 (51.9) |  |
Residential source | ||||
 Rural | 928 (64.4) | 469 (67.4) | 459 (61.6) | .022 |
 Urban | 513 (35.6) | 227 (32.6) | 286 (38.4) |  |
Monthly cost of living | ||||
 ≤ 800 RMB | 494 (34.3) | 212 (30.5) | 282 (37.9) | .008 |
 800–1200 RBM | 714 (49.5) | 371 (53.3) | 343 (46.0) |  |
 ≥ 1200 RMB | 233 (16.2) | 113 (16.2) | 120 (16.1) |  |
Most personally relevant smartphone function | ||||
 Phone calls/Text message | 505 (35.0) | 235 (33.9) | 270 (36.2) | .000 |
 Smartphone gaming | 60 (4.2) | 49 (7.0) | 11 (1.5) |  |
Multimedia applications (Watching videos/Listening to music) | 230 (16.0) | 108 (15.4) | 122 (16.3) | Â |
 Social networking services | 483 (33.5) | 208 (29.9) | 275 (36.9) |  |
 Internet surfing/reading | 92 (6.4) | 57 (8.1) | 35 (4.7) |  |
 Others | 71 (4.9) | 39 (5.6) | 32 (4.3) |  |
Smart phone addiction | ||||
 Negative | 1012 (70.2) | 485 (69.7) | 527 (70.7) | .662 |
 Positive | 429 (29.8) | 211 (30.3) | 218 (29.3) |  |
Sleep quality | ||||
 Good sleep quality | 929 (64.5) | 467 (67.1) | 462 (62.0) | .044 |
 Poor sleep quality | 512 (35.5) | 229 (32.9) | 283 (38.0) |  |
Anxiety | ||||
 Negative | 1301 (90.3) | 607 (87.2) | 694 (93.2) | .000 |
 Positive | 140 (9.7) | 89 (12.8) | 51 (6.8) |  |
Depressive | ||||
 Negative | 1076 (74.7) | 501 (72.0) | 575 (77.2) | .023 |
 Positive | 365 (25.3) | 195 (28.0) | 170 (22.8) |  |