Table 1.

General Characteristics of study subjects of prevalence survey for non-suicidal self-injury among adolescents in South Korea, 2019.

Variables /Classification	Total	Male	Female
	n = 1843 (%)	n = 964 (%)	n = 879 (%)
School level
Middle school (12–14 years old)	1031 (55.9)	525 (54.5)	506 (57.6)
High school (15–17 years old)	812 (44.1)	439 (45.5)	373 (42.4)
School year
Middle school Year1 (12 years old)	340 (18.4)	172 (17.8)	168 (19.1)
Year2 (13 years old)	344 (18.7)	173 (17.9)	171 (19.5)
Year3 (14 years old)	347 (18.8)	180 (17.8)	167 (19.0)
High school Year1 (15 years old)	266 (14.4)	138 (14.3)	128 (14.6)
Year2 (16 years old)	262 (14.2)	143(14.8)	119 (13.5)
Year3 (17 years old)	284 (15.4)	158 (16.4)	126 (14.3)
School grades
High	249 (13.5)	149 (15.5)	100 (11.4)
Medium-high	486 (26.4)	241 (25.0)	245 (27.9)
Medium	567 (30.8)	284 (29.5)	283 (32.2)
Medium-low	382 (20.7)	201 (20.9)	181 (20.6)
Low	159 (8.6)	89 (9.2)	70 (8.0)
Economic status
High	234 (12.7)	152 (15.8)	82 (9.3)
Medium-high	565 (30.7)	292 (30.3)	273 (31.1)
Medium	884 (48.0)	432 (44.8)	452 (51.4)
Medium-low/Low	160 (8.7)	88 (9.1)	72 (8.2)
Current smoking. Yes (%)	97 (5.3)	75 (7.8)	22 (2.5)
Current drinking, yes (%)	188 (10.2)	120 (12.4)	68 (7.7)
Physical activity for 60min a day and 5 days or over a week, yes (%)	284 (15.4)	223 (23.1)	61 (6.9)
Non-suicide self-injury, yes (%)	163 (8.8)	45 (4.7)	118 (13.4)
Suicidal ideation, yes (%)	237 (12.9)	77 (8.0)	160 (18.2)
Suicidal plan, yes (%)	82 (4.4)	28 (2.9)	54 (6.1)
Suicidal attempts, yes (%)	59 (3.2)	11 (1.1)	48 (5.5)
Depressive symptom, yes (%)	502 (27.2)	201 (20.9)	301 (34.2)
Bullying victim, yes (%)	43 (2.3)	24 (2.5)	19 (2.2)
Gaming disorder, yes (%)	226 (12.3)	141 (14.6)	85 (9.7)