Table 2.

Hazard ratios (HR) with 95% confidence intervals (CI) of adolescent first-time self-harm by parental education and household income

	All cases			Severe cases
	Model 1 HR (95% CI)	Model 2 HR (95% CI)	Model 3 HR (95% CI)	Model 1 HR (95% CI)	Model 2 HR (95% CI)	Model 3 HR (95% CI)
Parental education
Primary	1.37 (1.22–1.55)	1.37 (1.21–1.54)	1.12 (0.99–1.24)	1.39 (1.07–1.82)	1.24 (0.94–1.63)	1.23 (0.92–1.64)
Secondary	1.33 (1.23–1.43)	1.29 (1.20–1.39)	1.18 (1.09–1.27)	1.13 (0.94–1.36)	1.09 (0.90–1.31)	1.08 (0.89–1.30)
Tertiary	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)
Household income
1st quintile	1.15 (1.02–1.29)	1.20 (1.07–1.36)	1.13 (1.00–1.27)	1.04 (0.78–1.38)	0.96 (0.71–1.29)	0.97 (0.72–1.31)
2nd quintile	1.37 (1.22–1.53)	1.34 (1.20–1.50)	1.20 (1.07–1.34)	1.08 (0.82–1.41)	1.00 (0.76–1.32)	0.99 (0.75–1.30)
3rd quintile	1.32 (1.18–1.47)	1.30 (1.16–1.45)	1.18 (1.05–1.32)	1.01 (0.77–1.34)	0.99 (0.75–1.32)	0.98 (0.74–1.30)
4th quintile	1.15 (1.03–1.29)	1.14 (1.01–1.27)	1.07 (0.96–1.21)	0.90 (0.67–1.21)	0.87 (0.65–1.18)	0.86 (0.64–1.16)
5th quintile	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)	1.00 (REF)

Model 1: adjusted for gender

Model 2: adjusted for gender, parental country of birth and history of mental disorder of biological parent

Model 3: adjusted for gender, parental country of birth, history of mental disorder of biological parent, receipt of welfare and number of parents in the household