Table 3. Hierarchical logistic regression analyses results of participants with NSSI and MSA, with MSA as the dependent variable (N = 247a).
| Independent variables | Model 1 | Model 2 | Model 3 | Model 4 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| B | Wald | OR | B | Wald | OR | B | Wald | OR | B | Wald | OR | ||
| Demographics and historical factors | |||||||||||||
| Age, yr | < 0.01 | < 0.01 | 1.00 | < 0.01 | 0.04 | 1.00 | < 0.01 | 0.08 | 1.00 | < 0.01 | 0.03 | 1.00 | |
| Sex (female) | −0.59 | 2.27 | 0.56 | −0.49 | 1.50 | 0.62 | −0.47 | 1.38 | 0.62 | −0.28 | 0.48 | 0.75 | |
| Previous suicide attempts (yes) | 0.64 | 4.02 | 1.90* | 0.57 | 3.01 | 1.76 | 0.53 | 2.53 | 1.69 | 0.27 | 0.58 | 1.31 | |
| Psychiatric treatment (yes) | 0.61 | 2.24 | 1.84 | 0.80 | 3.53 | 2.23 | 0.96 | 4.73 | 2.60* | 0.78 | 2.84 | 2.17 | |
| Psychiatric hospitalizations (yes) | −0.09 | 0.07 | 0.91 | −0.11 | 0.10 | 0.90 | < 0.01 | < 0.01 | 1.00 | 0.15 | 0.16 | 1.16 | |
| Characteristics of self-injury | |||||||||||||
| Cutting (yes) | 0.16 | 0.29 | 1.18 | 0.21 | 0.46 | 1.23 | 0.21 | 0.40 | 1.23 | ||||
| Lethality of injury (higher) | 0.66 | 4.77 | 1.93* | 0.67 | 4.83 | 1.95* | 1.06 | 9.85 | 2.88** | ||||
| Status at the time of self-injury | |||||||||||||
| Planned (yes) | 1.98 | 3.08 | 7.21 | 1.96 | 2.46 | 7.12 | |||||||
| Alcohol (yes) | 0.36 | 1.11 | 1.44 | 0.50 | 1.85 | 1.64 | |||||||
| Suicide note (yes) | 0.55 | 0.43 | 1.74 | 0.64 | 0.58 | 1.90 | |||||||
| Seeking help (yes) | −0.32 | 1.13 | 0.73 | −0.35 | 1.25 | 0.70 | |||||||
| Current suicidal ideation and plans | |||||||||||||
| Sustained suicidal ideation (yes) | 1.06 | 7.94 | 2.87** | ||||||||||
| Future suicidal plans (yes) | 0.72 | 3.29 | 2.05 | ||||||||||
| Statistics of the model | |||||||||||||
| -2LL | 303.173 | 298.317 | 291.680 | 271.431 | |||||||||
| Model χ2 | 9.384 (df = 5) | 14.241 (df = 7)* | 20.877 (df = 11)* | 41.126 (df = 13)*** | |||||||||
| Step χ2 | 9.384 (df = 5) | 4.857 (df = 2) | 6.636 (df = 4) | 20.249 (df = 2)*** | |||||||||
| Nagelkerke R2 | 0.052 | 0.078 | 0.113 | 0.214 | |||||||||
| Classification accuracy | 67.2 | 68.8 | 66.4 | 68.8 | |||||||||
NSSI = non-suicidal self-injury, MSA = minor intent suicide attempt, OR = odds ratio.
*P < 0.05, **P < 0.01, ***P < 0.001.
aCases with missing values for any independent variable were excluded from the analysis.