Table 6.

The difference in bullying prevalence among different grade levels.

	Category	Members	Primary school	Junior high school	Senior high school	χ2	P-value
Whether being bulling	Being bullied	68,342 (71.6%)	18,271 (67.4%)	31,964 (74.1%)	18,107 (71.8%)	1.1	0.56
	Not being bullied	27,113 (28.4%)	8,857 (32.6%)	11,160 (25.9%)	7,096 (28.2%)
Types of bullying	Physical victimization	30,720 (32.2%)	16,470 (60.7%)	13,923 (32.3%)	6,139 (24.4%)	16	**
	Verbal victimization	57,104 (59.8%)	15,530 (57.2%)	27,194 (63.1%)	14,380 (57.1%)
	Social manipulation	43,028 (45.1%)	12,327 (45.4%)	20,080 (46.6%)	10,621 (42.1%)
	Attacks on property	54,729 (57.3%)	14,495 (53.4%)	25,663 (59.5%)	14,571 (57.8%)
Severity of bullying	Mild bullying	56,372 (82.5%)	14,160 (77.5%)	26,526 (83%)	15,956 (88.1%)	3.9	**
	Severe bullying	11,970 (17.5%)	4,111 (22.5%)	5,708 (17%)	2,151 (11.9%)