Table 3 An analysis of socio-demographic risk factors for emergency presentations with self-harm amongst 113,543 adolescents residing in South London using crude and multivariable cox-regression analyses
Socio-demographic characteristics | Male (n=56,648) | Female (n=56,897) | ||||||
|---|---|---|---|---|---|---|---|---|
No self-harm (n=56,462) | Self-harm (n=186) | Unadjusted hazard ratio | Adjusted hazard ratiob | No self-harm (n=56,063) | Self-harm (n=834) | Unadjusted hazard ratio | Adjusted hazard ratiob | |
Mean age at baseline (SD) | 12.8 (2.1) | 14.1 (1.8) | 1.70 (1.55–1.86)** | 1.38 (1.22–1.57)** | 12.8 (2.0) | 13.9 (1.8) | 1.48 (1.42–1.54)** | 1.28 (1.21–1.35)** |
Mean duration of follow-up (SD) | 2.73 (1.3) | 1.89 (1.2) | - | - | 2.70 (1.3) | 1.86 (1.1) | - | - |
Ethnicity | (n, %) | (n, %) | (n, %) | (n, %) | ||||
 White | 20,943 (37.1) | 88 (47.3) | Reference | Reference | 20,534 (36.6) | 357 (42.8) | Reference | Reference |
 Black | 20,842 (36.9) | 28 (15.0) | 0.32 (0.21–0.48)** | 0.38 (0.23–0.65)** | 21,106 (37.7) | 212 (25.4) | 0.57 (0.48–0.68)** | 0.58 (0.78–0.71)** |
 Asian | 4860 (8.6) | 12 (6.5) | 0.60 (0.33–1.10) | 0.87 (0.35–2.14) | 4865 (8.7) | 47 (5.7) | 0.58 (0.43–0.78)** | 0.61 (0.40–0.94)* |
 Mixed | 6234 (11.0) | 16 (8.6) | 0.62 (0.36–1.04) | 0.69 (0.37–1.26) | 6218 (11.1) | 102 (12.2) | 0.97 (0.77–1.20) | 1.12 (0.88–1.41) |
 Other | 1968 (3.5) | 12 (6.5) | 1.42 (0.78–2.60) | 0.64 (0.14–2.69) | 1880 (3.3) | 29 (3.5) | 0.88 (0.60–1.28) | 0.78 (0.46–1.31) |
 Not disclosed | 1615 (2.9) | 30 (16.1) | 4.9 (3.3–7.5)** | 0.74 (0.17–3.04) | 1460 (2.6) | 87 (10.4) | 4.0 (3.16–5.04)** | 0.94 (0.54–1.61) |
National neighbourhood deprivationa | ||||||||
 Most deprived quintile | 20,586 (36.5) | 63 (33.9) | Reference | Reference | 20,144 (35.9) | 320 (38.4) | Reference | Reference |
 2nd | 22, 855 (40.5) | 78 (42.5) | 1.14 (0.82–1.58) | 0.98 (0.63–1.53) | 22,720 (40.6) | 330 (39.5) | 0.92 (0.79–1.08) | 0.98 (0.81–1.17) |
 3rd | 7989 (14.2) | 32 (17.2) | 1.31 (0.86–2.20) | 1.40 (0.81–2.42) | 8193 (14.6) | 120 (14.4) | 0.95 (0.77–1.17) | 0.88 (0.67–1.15) |
 4th | 3378 (6.0) | <10 (<5.4) | 0.78 (0.38–1.64) | 0.74 (0.28–1.88) | 3311 (5.9) | 44 (5.3) | 0.85 (0.62–1.16) | 0.80 (0.55–1.18) |
 Least deprived | 1620 (2.9) | <10 (<5.4) | 0.81 (0.29–2.21) | 0.27 (0.04–2.01) | 1677 (3.0) | 20 (2.4) | 0.75 (0.48–1.18) | 0.79 (0.46–1.3) |