Table 5. Adjusted OR (95% CI ) for Bullying, Victimization and Bully-victim by multi-level logistic regression.

Covariates	Bully		Victim		Bully-Victim*
	Adjusted OR	95%CI	Adjusted OR	95%CI	Adjusted OR	95%CI
Gender (Girl vs. Boy)	1.04	0.88–1.22	1.06	0.94–1.20	1.07	0.89–1.29
Grade (Junior vs. Senior)	0.36	0.27–0.48#	0.57	0.45–0.72#	0.26	0.18–0.36#
Pocket money (RMB)
<100	1.00		1.00		1.00
100–199	1.09	0.90–1.30	0.84	0.73–0.96	1.07	0.87–1.31
≥200	1.31	1.00–1.69	1.01	0.83–1.23	1.27	0.96–1.69
Living arrangement
Two biological parents	-	-	1.00		-	-
Only father or mother	-	-	1.04	0.83–1.29	-	-
Others	-	-	1.09	0.94–1.26	-	-
Parental care
Satisfaction	1.00		1.00		1.00
General	1.30	1.06–1.59#	1.09	0.95–1.25	1.35	1.08–1.69#
Dissatisfaction	1.70	1.24–2.32#	1.28	1.07–1.53#	1.85	1.31–2.59#
Communication with parents
Often	1.00		1.00		1.00
General	1.11	0.92–1.34	1.16	1.00–1.35	1.04	0.84–1.29
Scare	1.11	0.86–1.42	1.55	1.22–1.98#	0.99	0.75–1.31
Economic status
Good	-	-	1.00		1.00
General	-	-	1.02	0.88–1.18	1.10	0.87–1.38
Bad	-	-	1.28	1.06–1.55#	1.48	1.11–1.98#
Academic achievement
Above average	-	-	1.00		1.00
Average	-	-	0.55	0.43–0.69#	0.45	0.31–0.65#
Below average	-	-	0.39	0.16–1.00	0.16	0.02–1.24
Classmate relations
Good	-	-	1.00
Average	-	-	1.44	1.17–1.77#	-	-
Bad	-	-	1.31	1.03–1.66#	-	-

^*bully-victim: Those students who participate in both bullying and victimization.

#:P<0.05.

“-”: Factors not included in the final multivariate analysis.