Table 3. Less-Frequent and More-Frequent NSSI by Possible Internet Addiction and Internet Addiction in Male vs Female Participants.
| Age groups | Male | Female | RORc | P valued | ||||
|---|---|---|---|---|---|---|---|---|
| No. (%) | OR (95% CI)a | OR (95% CI)b | No. (%) | OR (95% CI)a | OR (95% CI)b | |||
| Total | ||||||||
| Less-frequent NSSI | ||||||||
| Non–internet addiction | 659 (13.8) | 1 [Reference] | 1 [Reference] | 963 (17.0) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 557 (19.1) | 1.64 (1.45-1.86) | 1.44 (1.07-1.93) | 379 (21.5) | 1.61 (1.41-1.85) | 1.15 (1.02-1.35) | 1.25 | .41 |
| Internet addiction | 72 (19.9) | 2.05 (1.54-2.71) | 1.42 (1.24-1.62) | 37 (25.0) | 3.07 (2.00-4.69) | 1.60 (1.04-2.53) | 0.89 | .34 |
| More-frequent NSSI | ||||||||
| Non–internet addiction | 386 (8.1) | 1 [Reference] | 1 [Reference] | 481 (8.5) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 433 (14.9) | 2.18 (1.88-2.52) | 1.64 (1.40-1.92) | 350 (19.9) | 2.98 (2.56-3.48) | 1.83 (1.55-2.16) | 0.90 | .18 |
| Internet addiction | 90 (24.9) | 4.37 (3.33-5.72) | 2.38 (1.77-3.19) | 58 (39.2) | 9.62 (6.55-14.13) | 3.42 (2.23-5.24) | 0.70 | .11 |
| 11-14 y | ||||||||
| Less-frequent NSSI | ||||||||
| Non–internet addiction | 298 (14.7) | 1 [Reference] | 1 [Reference] | 427 (18.0) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 225 (21.6) | 1.80 (1.48-2.19) | 1.53 (1.25-1.88) | 128 (21.9) | 1.66 (1.32-2.09) | 1.13 (0.90-1.47) | 1.35 | .03 |
| Internet addiction | 24 (18.3) | 1.97 (1.21-3.20) | 1.44 (0.89-2.40) | 13 (20.3) | 2.93 (1.43-6.03) | 1.57 (0.75-3.36) | 0.92 | .43 |
| More-frequent NSSI | ||||||||
| Non–internet addiction | 166 (8.2) | 1 [Reference] | 1 [Reference] | 218 (9.2) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 164 (15.7) | 2.36 (1.87-2.98) | 1.79 (1.39-2.29) | 143 (24.5) | 3.63 (2.85-4.63) | 2.11 (1.62-2.76) | 0.85 | .19 |
| Internet addiction | 43 (32.8) | 6.33 (4.16-9.61) | 3.69 (2.34-5.82) | 33 (51.6) | 14.57 (8.07-26.33) | 5.19 (2.68-10.32) | 0.71 | .24 |
| 15-17 y | ||||||||
| Less-frequent NSSI | ||||||||
| Non–internet addiction | 200 (12.7) | 1 [Reference] | 1 [Reference] | 298 (16.7) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 187 (17.8) | 1.64 (1.32-2.04) | 1.41 (1.11-1.78) | 148 (20.8) | 1.55 (1.24-1.94) | 1.16 (0.92-1.48) | 1.22 | .13 |
| Internet addiction | 31 (20.7) | 2.17 (1.40-3.35) | 1.49 (0.94-2.38) | 14 (26.4) | 2.73 (1.39-5.37) | 1.65 (0.85-3.30) | 0.9 | .41 |
| More-frequent NSSI | ||||||||
| Non–internet addiction | 127 (8.1) | 1 [Reference] | 1 [Reference] | 153 (8.6) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 151 (14.4) | 2.09 (1.62-2.69) | 1.48 (1.12-1.94) | 134 (18.8) | 2.72 (2.11-3.52) | 1.79 (1.35-2.37) | 0.83 | .18 |
| Internet addiction | 30 (20.0) | 3.30 (2.10-5.19) | 1.60 (1.01-2.67) | 16 (30.2) | 6.07 (3.14-11.75) | 2.82 (1.37-5.83) | 0.57 | .16 |
| 18-20 y | ||||||||
| Less-frequent NSSI | ||||||||
| Non–internet addiction | 161 (13.7) | 1 [Reference] | 1 [Reference] | 238 (15.8) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 145 (17.7) | 1.49 (1.16-1.91) | 1.34 (1.04-1.75) | 103 (22.2) | 1.74 (1.33-2.26) | 1.23 (0.93-1.65) | 1.09 | .34 |
| Internet addiction | 17 (21.2) | 2.11 (1.19-3.77) | 1.43 (0.80-2.68) | 10 (32.3) | 4.06 (1.73-9.50) | 1.78 (0.74-4.45) | 0.80 | .37 |
| More-frequent NSSI | ||||||||
| Non–internet addiction | 93 (7.9) | 1 [Reference] | 1 [Reference] | 110 (7.3) | 1 [Reference] | 1 [Reference] | ||
| Possible internet addiction | 118 (14.4) | 2.10 (1.57-2.81) | 1.66 (1.21-2.27) | 73 (15.7) | 2.66 (1.73-3.68) | 1.57 (1.11-2.23) | 1.06 | .41 |
| Internet addiction | 17 (21.2) | 3.65 (2.01-6.63) | 2.03 (1.06-3.90) | 9 (29.0) | 7.90 (3.26-19.17) | 2.29 (0.87-6.24) | 0.89 | .43 |
Abbreviations: NSSI, nonsuicidal self-injury; OR, odds ratio; ROR, ratio of ORs.
a
Unadjusted model.
b
Adjusted for province, age (in total model), grade, ethnicity, family income, family structure, single-child family, parents’ educational level, parenting style, emotional management ability, loneliness, psychological resilience, suicidal ideation, and suicide attempt.
c
Calculated by adjusted OR.
d
One-sided P value.