A total of 6,836 responses were included in the final analytic sample. The average age of the participants (n = 6,836; 35.5% male) was 20.95 years (
SD = 2.7). The demographic characteristics of the sample are summarized in Table
1.
Table 1
Demographic characteristics of the study sample (N = 6836)
Sex | Male | 2,428 | 35.5 |
Female | 4,408 | 64.5 |
Education | Undergraduate | 3,175 | 46.4 |
Graduate | 3,661 | 53.6 |
Major | Liberal arts | 2,878 | 42.1 |
Science & Engineering | 3,958 | 57.9 |
Distribution of suicide risk
We found that 18% (n=1230) of the students had high suicide ideation (SSI ≥ 6), and 14.5% (n=991) had suicide risk (SBQ-R ≥ 7). In addition, 18.8% (n=1285) had thought about specific plans for suicide (17.2%, n=1176) or had specific plans (1.6%, n=109; SSI Q12), 1% had attempted suicide (SBQ-R Q1), and 0.4% (n=27) had prepared a suicide note (SSI Q17).
Distribution and characteristics of suicide ideation and behavior
Descriptive data relating to SSI and SBQ-R scores by sex, education level, and major subjects are listed in Table
2. Independent
t-tests showed that SSI and SBQ-R scores were significantly higher in female, undergraduate, and liberal arts students than male, graduate, and science students, respectively (
p < 0.05). The proportion of students who had SSI or SBQ-R scores that reached the threshold were also higher in these three groups as determined by Chi-square tests (
p < 0.05).
Table 2
Descriptive data and group difference of scores of SSI and SBQ-R
| | t | d | n | % | χ2 | d | | t | d | n | % | χ2 | d |
Male | 3.49 (3.60) | -2.34* | -0.06 | 401 | 16.5 | 5.68* | 0.06 | 4.03 (1.94) | -6.15*** | -0.16 | 287 | 11.8 | 21.98*** | 0.11 |
Female | 3.70 (3.43) | | | 830 | 18.8 | | | 4.36 (2.24) | | | 705 | 16.0 | | |
Undergraduate | 4.32 (4.14) | 15.61*** | 0.38 | 793 | 25.0 | 195.00*** | 0.34 | 4.72 (2.52) | 17.52*** | 0.42 | 665 | 20.9 | 197.80*** | 0.35 |
Graduate | 3.02 (2.67) | | | 438 | 12.0 | | | 3.83 (1.64) | | | 327 | 8.9 | | |
Liberal arts | 3.79 (3.66) | 3.42*** | 0.08 | 574 | 19.9 | 12.63*** | 0.09 | 4.36 (2.27) | 3.86*** | 0.01 | 459 | 15.9 | 8.28** | 0.07 |
Science & Engineering | 3.50 (3.37) | | | 657 | 16.6 | | | 4.15 (2.04) | | | 533 | 13.5 | | |
Total | 3.62 (3.49) | | | 1231 | 18.0 | | | 4.24 (2.12) | | | 992 | 14.5 | | |
Characteristics of suicide ideation
Table
3 shows descriptive data collected from the 19-item SSI measure. The proportion of partial suicide ideation was above 10%: 18.2% (
n=1244) of the students indicated a weak (17%,
n=1162) or medium to strong (1.2%,
n=82) desire to die (Q2); 14.7% (
n=1005) reported that they accepted the concept of suicide (Q8); 12.6% reported that they did not have compelling reasons (8.2% had some reason, whereas 4.4% had little or no reason) to abandon suicide (Q10); 61.4% (
n=4197) thought suicide could help people end or evade problems (Q11); 18.8% (
n=1285) reported specificity(1.6%) or planning(17.2%) of contemplated attempt (Q12); and 10.7% (
n=731) of students reported that they would resolutely hide the attempt at suicide (Q19).
Table 3
Descriptive data of SSI
1. Wish to live | 1.05 (0.25) | 94.8 | 4.8 | 0.4 |
2. Wish to die | 1.20 (0.43) | 81.7 | 17.0 | 1.2 |
3. Reason for living/dying | 1.07 (0.29) | 93.6 | 5.6 | 0.8 |
4. Desire to make active suicide attempt | 1.10 (0.32) | 90.7 | 8.6 | 0.7 |
5. Passive suicidal desire | 1.05 (0.25) | 96.2 | 2.9 | 0.9 |
6. Time dimension: duration of suicide ideation/wish | 1.05 (0.27) | 96.1 | 2.6 | 1.3 |
7. Time dimension: frequency of suicide | 1.06 (0.25) | 94.7 | 4.8 | 0.5 |
8. Attitude toward ideation/wish | 1.46 (0.74) | 68.5 | 16.8 | 14.7 |
9. Control over suicidal action/acting-out wish | 1.07 (0.29) | 93.7 | 5.4 | 1.0 |
10. Deterrents to active attempt | 1.17 (0.48) | 87.3 | 8.2 | 4.4 |
11. Reason for contemplated attempt | 2.51 (0.67) | 10.2 | 28.3 | 61.4 |
12. Method: specificity or planning of contemplated attempt | 1.20 (0.44) | 81.1 | 17.2 | 1.6 |
13. Method: availability or opportunity for contemplated attempt | 1.12 (0.41) | 91.6 | 5.2 | 3.2 |
14. Sense of "capability" to carry out attempt | 1.11 (0.36) | 90.6 | 7.9 | 1.5 |
15. Expectancy/anticipation of actual attempt | 1.07 (0.28) | 94.3 | 4.8 | 0.9 |
16. Actual preparation for contemplated attempt | 1.01 (0.13) | 98.8 | 1.1 | 0.2 |
17. Suicide note | 1.03 (0.19) | 97.5 | 2.1 | 0.4 |
18. Final acts in anticipation of death | 1.04 (0.23) | 97.0 | 2.3 | 0.7 |
19. Deception or concealment of contemplated suicide | 1.25 (0.63) | 85.9 | 3.3 | 10.7 |
Predictive factors for suicide attempt and suicide risk
The results of the binary logistic regressions of factors predicting suicide attempt and high suicide risk are presented in Table
4.
Table 4
Binary logistic regression of factors predicting suicide attempt and suicide risk
Demographic characteristics |
Sex | 0.55 | 0.46 | 1.44 [0.55, 3.83] | 0.87 | 0.35 | 1.10 [0.90, 1.36] |
Education | 5.75 | 0.02 | 0.32 [0.12, 0.81] | 18.61 | <0.001 | 0.66 [0.54, 0.79] |
Major | 0.16 | 0.69 | 1.19 [0.51, 2.78] | 0.05 | 0.83 | 1.02 [0.84, 1.24] |
Suicide ideation |
SSI Q2 | 5.16 | 0.02 | 2.45 [1.13, 4.92] | 264.26 | <0.001 | 4.40 [3.68, 5.26] |
SSI Q8 | 14.15 | <0.001 | 2.56 [1.57, 4.17] | 207.94 | <0.001 | 2.29 [2.05, 2.57] |
SSI Q10 | 0.69 | 0.41 | 1.40 [0.63, 3.07] | 33.59 | <0.001 | 1.61 [1.37, 1.89] |
SSI Q11 | 0.05 | 0.82 | 0.93 [0.50, 1.74] | 0.13 | 0.72 | 0.97 [0.84, 1.13] |
SSI Q12 | 22.25 | <0.001 | 6.40 [2.96, 13.84] | 411.50 | <0.001 | 6.13 [5.15, 7.31] |
SSI Q19 | 6.11 | 0.01 | 1.87 [1.14, 3.07] | 71.34 | <0.001 | 1.67 [1.48, 1.88] |
Psychopathology |
PHQ-9 | 0.23 | 0.63 | 0.96 [0.82, 1.12] | 0.30 | 0.59 | 0.99 [0.96, 1.03] |
GAD-7 | 0.15 | 0.70 | 1.03 [0.88, 1.22] | 0.23 | 0.63 | 0.99 [0.95, 1.03] |
The results of the binary logistic regression of factors predicting suicide attempt showed that the resulting model was significant, χ2 (345) = 110.92, p < 0.001, Nagelkerke R2 = 0.64. The significant measures were found to be education (OR = 0.32, 95% CI [0.12, 0.81], p = 0.02), SSI-2 (wish to die; OR = 2.45, 95% CI [1.13, 4.92], p = 0.02), SSI-8 (attitude toward suicide; OR = 2.56, 95% CI [1.57, 4.17], p < 0.001), SSI-12 (specificity/planning of suicide; OR = 6.40, 95% CI [2.96, 13.84], p < 0.001), and SSI-19 (deception or concealment of contemplated suicide; OR = 1.87, 95% CI [1.14, 3.07], p = 0.01).
The results of the binary logistic regression of factors predicting high suicide risk showed that the resulting model was significant, χ2 (5,952) = 2141.31, p < 0.001, Nagelkerke R2 = 0.55. The significant measures were found to be education (OR = 0.66, 95% CI [0.54, 0.79], p < 0.001), SSI Q2 (wish to die; OR = 4.40, 95% CI [3.68, 5.26], p < 0.001), SSI Q8 (attitude toward suicide; OR = 2.29, 95% CI [2.05, 2.57], p < 0.001), SSI Q10 (deterrents to active attempt; OR = 1.61, 95% CI [1.37, 2.57], p < 0.001), SSI Q12 (specificity/planning of suicide; OR = 6.13, 95% CI [5.15, 7.31], p < 0.001), and SSI Q19 (deception or concealment of contemplated suicide; OR = 1.67, 95% CI [1.48, 1.88], p < 0.001).
Relationship between suicidality and depressive/anxiety symptoms
The correlation between suicidality and depressive/anxiety symptoms showed that suicide ideation and suicidal behavior were positively correlated with depressive and anxiety symptoms, respectively (p < 0.001). However, the correlation between scores of the SSI and PHQ-9 (r = 0.13), SSI and GAD-7 (r = 0.11), SBQ-R and PHQ-9 (r = 0.09), and SBQ-R and GAD-7 (r = 0.08) were all weak.
Of the students with a history of suicide attempts, 18.2% (n=1244) showed elevated depressive symptoms, and 13.6% (n=930) showed elevated anxiety symptoms. The proportion of students without a history of suicide attempts showing elevated depressive and anxiety symptoms was 7.6% (n=520) and 4.5% (n=308), respectively. The proportion of all students with high suicide risk who showed high depressive and anxiety symptoms was 10.8% (n=738) and 5.6% (n=383), respectively. The proportion of all students with low suicide risk who showed high depressive and anxiety symptoms was 7.2% (n=492) and 4.4% (n=301), respectively.