Table 1. Questionnaire items (sample)
Q1 What is your school grade?
Q3 What is your sex?
Q4 How many siblings do you have?
Q8 How many friends do you have? (very many, many, not so many, very few, unknown)
Q10 How often do you feel happy? (always, often, sometimes, rarely, never)
Q11 How often do you feel well? (always, often, sometimes, rarely, never)
Q12 How often do you feel lonely? (always, often, sometimes, rarely, never)
Q13How often do you talk with your family? (always, often, sometimes, rarely, never)
Q14 Have you ever experienced cyberbullying? (yes, no)
Q15 In the past year, have you seriously considered killing yourself? (no, sometimes, always, attempted suicide, no idea)
Q17 Do you have stressors about the following: body image; secondary sexual characteristics; friends; conventional bullying; parents; siblings; school records; opposite sex; sexual identity or intercourse; sexually transmitted infections; induced abortion; contraception; marriage; pregnancy, child care; physical illness; academic course; alcohol, smoking, or substance use?
Table 2. Participants’ geographic location and school type
Junior high school High school Total
(n = 13,285) (n = 9,134) (N = 22,419)
School type Public Private Public Private Total
Region
Urban 746 1,957 1,304 3,346 7,353
Suburban 8,449 162 1,923 803 11,337
Rural 1,971 0 1,758 0 3,729
Table 3. Prevalence of suicide ideation and suicide attempts
n None Suicidal ideation Suicide attempt
Total 22,419 15,245 68.0% 5,765 25.7% 1,206 5.4%
Grade 7th 4,371 3,011 68.9% 1,123 25.7% 203 4.6%
8th 4,486 3,088 68.8% 1,130 25.2% 233 5.2%
9th 4,396 3,043 69.2% 1,054 24.0% 261 5.9%
10th 3,683 2,492 67.7% 961 26.1% 191 5.2%
11th 3,024 1,990 65.8% 836 27.6% 176 5.8%
12th 2,396 1,595 66.6% 648 27.0% 138 5.8%
Sex Male 8,907 6,606 74.2% 1,925 21.6% 309 3.5%
Female 13,454 8,613 64.0% 3,830 28.5% 893 6.6%
The numbers and percentages of participants who selected “no idea” for suicidal question do not appear
in the table. The numbers of participants with missing values for each factor likewise do not appear.
Table 4 . Logistic regression analysis in junior high and high school children
Junior high school children High school children
Variables Crude OR 95%CI p value Adjusted OR* 95%CI p value Crude OR 95%CI p value Adjusted OR* 95%CI p value
Grade 0.99 0.95–1.04 0.685 1.00 0.95–1.06 0.972 1.04 0.98–1.10 0.192 1.03 0.96–1.09 0.461
Sex 1.75 1.62–1.89 < 0.001 1.61 1.47–1.77 < 0.001 1.42 1.29–1.57 < 0.001 1.67 1.48–1.88 < 0.001
Number of siblings 0.95 0.85–1.05 0.311 1.06 0.93–1.20 0.412 0.76 0.70–0.89 < 0.001 0.86 0.75–0.99 < 0.05
Number of friends 1.40 1.36–1.44 < 0.001 1.05 1.01–1.09 < 0.05 1.31 1.26–1.36 < 0.001 1.05 1.00–1.10 < 0.05
Happiness 2.00 1.92–2.07 < 0.001 1.51 1.44–1.58 < 0.001 1.93 1.85–2.02 < 0.001 1.48 1.40–1.57 < 0.001
Wellness 1.74 1.68–1.80 < 0.001 1.24 1.18–1.29 < 0.001 1.72 1.64–1.79 < 0.001 1.28 1.22–1.35 < 0.001
Loneliness 0.51 0.50–0.53 < 0.001 0.69 0.66–0.72 < 0.001 0.51 0.49–0.53 < 0.001 0.65 0.62–0.68 < 0.001
Talk with family 1.41 1.36–1.46 < 0.001 1.15 1.10–1.20 < 0.001 1.37 1.31–1.43 < 0.001 1.11 1.05–1.17 < 0.001
Experience of cyberbullying 6.45 4.74–8.78 < 0.001 3.05 2.12–4.39 < 0.001 5.58 4.03–7.73 < 0.001 3.64 2.51–5.30 < 0.001
Stressors about
Relationship with friends 3.68 3.39–4.00 < 0.001 1.57 1.42–1.74 < 0.001 3.05 2.75–3.38 < 0.001 1.37 1.21–1.55 < 0.001
School bullying 5.28 4.34–6.42 < 0.001 1.88 1.49–2.37 < 0.001 8.94 5.18–15.43 < 0.001 2.62 1.40–4.90 < 0.005
Relationship with parents 4.97 4.39–5.63 < 0.001 2.10 1.81–2.44 < 0.001 4.20 3.62–4.87 < 0.001 2.12 1.78–2.53 < 0.001
School records 1.79 1.65–1.93 < 0.001 1.24 1.13–1.37 < 0.001 1.56 1.43–1.71 < 0.001 1.20 1.07–1.34 < 0.005
Relationship with opposite sex 3.02 2.69–3.39 < 0.001 1.82 1.58–2.09 < 0.001 2.07 1.81–2.36 < 0.001 1.35 1.15–1.59 < 0.001
Sexual identity or intercourse 3.84 3.03–4.86 < 0.001 1.38 1.03–1.84 < 0.05 3.78 2.91–4.92 < 0.001 2.18 1.58–3.01 < 0.001
Academic course 1.72 1.59–1.86 < 0.001 1.18 1.07–1.30 < 0.001 1.51 1.38–1.66 < 0.001 1.14 1.02–1.28 < 0.05
Tobacco use 2.44 1.91–3.10 < 0.001 1.34 0.95–1.88 0.098 2.70 1.75–4.15 < 0.001 1.25 0.72–2.17 0.438
Substance use 2.20 1.56–3.11 < 0.001 0.77 0.47–1.27 0.304 4.37 1.98–9.67 < 0.001 0.79 0.28–2.21 0.650
Region 0.86 0.80–0.91 < 0.001 0.94 0.87–1.01 0.083 1.10 1.04–1.16 < 0.001 1.19 1.11–1.27 < 0.001
OR; odd ratio, * Multiple logistic regression analysis including all variables listed in this table