Factors influencing non-suicidal self-injury in adolescents with mood disorders: Focusing on gender differences and only-child vs non-only-child disparities

Table 6 Univariate analysis of non-suicidal self-injury characteristics between only-child and non-only-child adolescents, n (%)/mean ± SD

Variables	Only-child (n = 296)	Non-only-child (n = 152)	t/χ2	P value
Sociodemographic characteristics
Age (years)	15.32 ± 1.85	15.43 ± 1.78	-0.625	0.533
Gender			1.037	0.309
Male	82 (27.70)	44 (28.95)
Female	214 (72.30)	108 (71.05)
Family monthly income			4.216	0.122
< 5000	72 (24.32)	36 (23.68)
5000-10000	144 (48.65)	68 (44.74)
> 10000	80 (27.03)	48 (31.58)
Parental marital status			6.895	0.009
Married	229 (77.36)	135 (88.81)
Divorced/remarried	67 (22.64)	17 (11.18)
Parental education level			3.126	0.077
≤ High school	136 (45.95)	68 (44.74)
> High school	160 (54.05)	84 (55.26)
Residential area			0.587	0.444
Urban	206 (69.59)	106 (69.74)
Rural	90 (30.41)	46 (30.26)
Clinical factors
Duration of mood disorder (months)	14.91 ± 6.42	14.65 ± 6.21	0.439	0.661
Comorbid obsessive-compulsive symptoms	124 (41.89)	62 (40.79)	0.068	0.795
Psychological assessments
SCS self-warmth	30.75 ± 7.58	33.92 ± 7.26	-4.587	< 0.001
SCS self-coldness	52.86 ± 8.15	49.21 ± 8.03	4.321	< 0.001
ERQ cognitive reappraisal	19.85 ± 6.37	22.46 ± 6.12	-4.218	< 0.001
ERQ expressive suppression	17.62 ± 5.08	17.51 ± 5.17	0.214	0.830
K-10 score	37.95 ± 7.38	34.62 ± 7.15	4.785	< 0.001
CTQ total score	54.12 ± 10.76	53.15 ± 10.89	0.824	0.410
Family functioning
FACES III cohesion	40.85 ± 8.47	44.92 ± 8.23	-5.214	< 0.001
FACES III adaptability	38.42 ± 7.89	39.25 ± 7.96	-1.021	0.307

SCS: Self-Compassion Scale; ERQ: Emotion Regulation Questionnaire; K-10: Kessler Psychological Distress Scale; CTQ: Childhood Trauma Questionnaire; FACES: Family Adaptation and Cohesion Evaluation Scales.