Table 3 Data extracted from included studies on gender dysphoria/TGNC/TNB, and both suicidality and self-harm

Mak et al. [50]

USA

TGD

6327

18–25 year old

Suicide attempts/self-inflicted injury rates

Multivariable Cox regression analyses

Incidence of the first self-harm—HR (95% CI)

Overall cohort 3.25 [1.84 to 5.74]

AFAB 3.76 (1.79 to 7.89)

AMAB 2.57 (1.01 to 6.55)

Incidence of Recurrent Self-Harm- HR (95%CI)

Overall cohort 2.87 (1.65 to 4.97)

AFAB TF cohort 3.57 (1.77 to 7.21)

AMAB 2.13 (0.90 to 5.03)

Thoma et al. [25]

USA

Transgender (including gender-nonconforming, nonbinary, questioning gender identity) and cisgender adolescents

2020 (1148 TGAs) (872 CGAs)

14–18 year old

Transgender

x̄ = 16.0 ± 1.2

Cisgenders

x̄ = 15.9 ± 1.1

Passive death wish; suicidal ideation; suicide plan; suicide attempt; NSSI

Descriptive statistics for suicidality outcome within gender identity groups (95%CI)

Multivariate logistic regression

Multivariate logistic regression adjusted models

Suicidal ideation (range):

All transgender (84.8%) (82.7% to 86.9%)

All cisgender (60.4%) (57.1% to 63.7%)

Nonbinary assigned female (79.2%) (75.1% to 83.3%)

Nonbinary assigned male (72.1%) (58.5% to 85.7%)

Questioning (82.4%) (71.8% to 93.0%)

NSSI (range):

All transgender status (86.9%) (84.9% to 88.9%)

All cisgender (59.1%) (55.8% to 62.4%)

Nonbinary assigned female (87.6%) (84.2% to 91.0%)

Nonbinary assigned male (76.7%) (63.9% to 89.5%)

Questioning 76.5(%) (64.7% to 88.3%)

95% CI

All transgender status (range)

Passive death wish: 93.0% to 95.6%

Suicidal ideation: 82.7% to 86.9%

Planning attempt: 70.0% to 75.1%

Suicide attempt: 47.4% to 53.2%

NSSI: 84.9% to 88.9%

Non-binary assigned female (range)

Passive death wish: 89.6% to 95.0%

Suicidal ideation: 58.5% to 85.7%

Planning attempt: 64.9% to 74.3%

Suicide attempt: 39.3% to 49.3%

NSSI: 84.2% to 91.0%

Non-binary male (range)

Passive death wish: 75.5% to 96.5%

Suicidal ideation: 58.5% to 85.7%

Planning attempt: 33.7% to 63.9%

Suicide attempt: 29.2% to 59.2%

NSSI: 95% CI 63.9% to 89.5%

All cisgender (range)

Passive death wish: 74.2% to 79.8 8%

Suicidal ideation: 57.1% to 63.7%

Planning attempt: 46.5% to 53.1%

Suicide attempt: 28.3% to 34.5%

NSSI: 55.8% to 62.4%

Higher OR for TGAs:

Passive Death Wish (OR = 2.60)

Suicidal Ideation (OR = 2.20)

Planning attempt (OR = 1.82)

Suicidal attempt (OR = 1.65)

Attempt requiring medical care (OR = 2.01)

NSSI (OR = 2.88)

Veale et al. [52]

Canada

TNB youth;

Cisgender population

923

14–18 year old (n = 323)

19–25 year old (n = 600)

139 transgender girls/women (16.6%)

356 transgender boys/men (42.4%)

344 non-binary (41.0%), mostly females at birth (n = 283)

Self-harm; suicidal ideation; suicide attempts

T-test with Cohen’s d/χ² for comparing transgender youth and general cisgender population mean scores

ANOVA post hoc Tukey comparisons for mean scores: differences between subgroup

Ages 14–18 years

Considering suicide (past year) BCAHS in school: 13.0%

Trans youth entire sample: n = 199 65.2%; χ²_{(df 1)} = 472.56** (p < 0.01); Effect size (RR = 5.02)

Times attempted (past year) BCAHS in school: x̄ ± SD = 0.11 ± 0.47

Trans youth entire sample: n = 199 x̄ ± SD = 0.65 ± 1.00; Student’s t₍₁₉₈₎ = 7.62** (p < 0.01); Effect size (d = 1.15)

At least one attempt (past year) BCAHS in school: 6.5%

Trans youth entire sample: N = 199 36.1%; χ² _{(d.f. 1)} = 290.64** (p < 0.01); Effect size (RR = 5.55)

Self-harm

Number of times (past year) BCAHS in school: x̄ ± SD = 0.41 ± 1.03

Trans youth entire sample: n = 231 x̄ ± SD = 1.87(1.27); Student’s t₍₂₃₀₎ = 17.47** (p < 0.01); Effect size (d = 1.42)

At least once in the past year BCAHS in school: 16.5%

Trans youth entire sample: n = 231 74.9%; χ²_{(d.f. 1)} = 540.93** (p < .01); Effect size (RR = 4.54)

Ages 19–25

Considered suicide (ever): CCHS (2012) 15.4%; TYHS (2014): n = 336 74.4%; χ²_{(d.f. 1)} = 893.37** (p < 0.01); Effect size (RR = 4.8)

Attempted suicide (ever): CCHS 3.4%; TYHS: n = 156 37.7%; χ²_(d.f.1) = 552.30** (p < 0.01); Effect size (RR = 11.12)

14–18–years-old

General mental health F(2,234) = 0.54

Seriously considered suicide (past year): Trans boys/men n = 90 68.9%; Trans Girls/Women n = 20; 55.0%; Non-binary n = 93; 64.5%; χ²_{(d.f. 2)} = 1.47

Self-harm at least once in the past year Trans Boys/men n = 106 79.2% Trans Girls/Women n = 24; 50.0%; Non-binary n = 100 77.0%; χ²_{(d.f. 2)} = 9.28* (p < .05)

19–25 years

General mental health F_(2,407) = 4.71 (p < 0.01)

Seriously considered suicide (ever) Trans Boys/men n = 139 76.8%; Trans Girls/Women n = 65; 66.2% Non-binary n = 97; 76.7%; χ²₍₂₎ = 3.12

Self-harm at least once in the past year Trans Boys/men n = 150; 48.0%; Trans Girls/Women n = 77; 40.3%; Non-binary n = 150; 60.7%; χ²₍₂₎ = 9.78** (p < 0.01)

Wang et al. [11]

China

TGNC (including nonbinary, questioning); Cisgender adolescents

12 108

2111 TGNC

9997 Cisgender

x̄ = 15.8 ± 1.0

AMAB = 6518

AFAB = 5590

Self-harm; suicidal ideation

Descriptive Statistics

Linear mixed-model analysis

Mixed-Effects Logistic Regression

x̄ (SD) for Self-harm and suicidal ideation:

Transgender AMAB = 4.03 (6.44%); AFAB = 3.51 (5.47%)

Nonbinary AMAB = 3.93 (6.69%); AFAB = 3.86(5.82)

Questioning AMAB = 2.57(4.72%); AFAB = 3.17(5.12)

Cisgender Boys 1.25 (3.60%); Girls 1.54 (3.79)

TGNC reporting a significantly lower overall health (t_11.872 =  − 7.36; p < 0.001), higher suicide ideation (t_11.860 = 12.22; p < 0.001), higher depression (t_11.830 = 12.43; p < 0.001), anxiety symptoms (t_11.847 = 11.47; p < 0.001) and higher sleep problems (t_11.683 = 10.49; p < 0.001) than cisgender youth

Youth AFAB reporting significantly lower level of overall health (t_11.866 =  − 7.91, p < 0.001), higher suicide ideation (t_11.866 = 3.44 p < 0.001), higher depression (t_11.827 = 3.88, p < 0.001),

higher anxiety symptoms (t_11.845 = 8.71, p < 0.001)

and sleep problems (t_11.676 = 2.79, p < 0.005) than AMAB youth

Compared with cisgender boys, significantly higher incidence (OR) of Past suicide attempts for:

Transgender girls: OR, 4.35; 95% CI, 2.88 to 6.56

Transgender boys: OR, 2.92; 95% CI, 2.26 to 3.76

Nonbinary AMAB: OR, 3.94; 95% CI, 2.36 to 6.55

Nonbinary AFAB: OR, 3.06; 95% CI, 1.67 to 5,63

Questioning youth AMAB: OR, 2.61; 95% CI, 1.73 to 3.94

Thoughts of self-harm for:

Transgender girls: OR, 3.06; 95% CI, 2.24 to 4.19

Transgender boys: OR, 4.06; 95% CI, 3.47 to 4.74

Suicide plan in the past month for:

Transgender girls: OR, 4.44; 95% CI, 2.88 to 6.83

Transgender boys: OR, 2.66; 95% CI, 2.03 to 3.50

Nonbinary youth AMAB: OR, 5.36; 95% CI, 3.22 to 8.93

Nonbinary youth AFAB: OR, 4.06; 95% CI, 2.25 to 7.30

Questioning youth AFAB: OR, 2.36; 95% CI, 1.63 to 3.43

Thoughts of suicide for:

Transgender girls: OR, 3.93;95% CI, 2.88 to 5.38

Transgender boys: OR, 3.71; 95% CI, 3.10 to 4.21

Deliberate self-harm during the last month for:

Transgender girls: OR, 2.74; 95% CI, 1.93 to 3.91

Transgender boys: OR, 3.06; 95% CI, 2.57 to 3.66

Nonbinary AMAB: OR, 2.56; 95% CI, 1.66 to 3.94

Nonbinary AFAB: OR, 3.06; 95% CI, 1.95 to 4.81

Becerra-Culqui et al. [53]

USA

TGNC;

cisgender youth

1082

Transfeminine Cohort = 427; 73%

Reference males = 4206; 72%

Reference females = 4204; 72‰)

Transmasculine Cohort = 655; 88%

Reference males = 6448; 88%

Reference females = 6459; 88%

10–17 year old

Suicidal ideation; self-inflicted injuries

Logistic Regression

Prevalence Ratios (RPs):

Transfeminine subjects compared with reference males for suicidal ideation: 54 (95% CI 18 to 218); For self-inflicted injuries: 70 (95% CI 9.0 to 159). Transmasculine subjects compared with reference males for suicide ideation: 45 [95% CI 23 to 97)

For self-inflicted injuries: 144 (95% CI 14 to 4338)

Bechard et al. [54]

Canada

Adolescents diagnosed with Gender Identity Disorder (GID) (DSM-IV-TR)

50

13–20 year old

x̄ = 16.9

Individuals assigned male at birth = 17

Individuals assigned female at birth = 33

Self-harm, suicidal ideation, and suicide attempts

Descriptive statistics

n(%)

Suicidal ideation = 31 (62%)

Self-harm = 18 (36%)

Suicide attempt(s) = 13 (26%)

Kozlowska et al. [21]

Australia

Children and Adolescents referred for GD;

Healthy Cisgenders

79 (GD)

155 (CIS)

GDs:

8.42–15.92 year old

x̄ = 12.84 ± 1.90

Median = 13.33

Biological males = 33 (41.8%)

Biological females (XX) = 46 (58.2%)

CIS:

8.33–15.97 yr old

x̄ = 12.9

Suicidal ideation, self-harm, suicide attempts

Descriptive statistics

T-test/χ²

Suicidal ideation (past or current): n = 33 (41.8%)

History of self-harm: n = 39 (16.3%)

Suicide attempts: n = 8 (10.1%)

Depressive disorder: n = 49 (62.0%)

Anxiety disorder: n = 50 (63.3%)

Significantly higher (t_[61.79] = 11.946; p < 0.001) Depression, Anxiety, and Stress Scale total scores between youth with GD and cis-controls

Significant difference between children with high (57/79; 72.2%) and low (22/79; 27.8%) levels of gender distress for:

History of self-harm (χ² = 11.86; p < 0.001);

Suicidal ideation (χ² = 6.98; p = 0.008)

Skagerberg et al. [22]

U.K

Adolescents referred for GD

125

x̄ = 13.56 ± 3.24

54.8% individuals assigned male at birth

45.2% individuals assigned female at birth

Suicide attempts; self-harming thoughts and behaviours

Descriptive statistics

χ²

Self-harm (24%); Thoughts of self-harm (14%); Suicide attempts (10%)

Males 16–18 yr of age (n = 20)

Thoughts of self-harm (37%) Self-harm (26%)

Females 12–15 yr of age n = 30)

Thought of self-harm (10%) Self-harm (37%) Suicide attempts (17%)

Actual self-harm more common in individuals assigned female at birth than individuals assigned male at birth (χ²[1] = 6.84, p < 0.01)

No significant difference between individuals assigned female at birth and individuals assigned male at birth for suicide attempts (χ²[1] = 0.87, p > 0.05)

Hartig et al. [30]

Germany

TGNC adolescents referred for GD

343

11–18 year old

x̄ = 15.47 ± 1.51

Male at birth (n = 56) x̄ = 15.69 ± 1.58

Female at birth (n = 287) x̄ = 15.42 ± 1.50

Risk of suicidal (suicidal ideation, suicide attempts) and non-suicidal self-harming thoughts and behaviours (STBs)

Descriptive statistics

CBCL parent-reported STBs for Item 18 (suicidal behaviour): Often (9.5%); Sometimes (20%)

Total = 29%

Youth self-reported STBs: often (19%), sometimes (26%), Total = 45%

CBCL parent-reported STBs for Item 91 (suicidal ideation): Often (2%); Sometimes (18%); Total = 20%

Youth self-reported STB: Often (13%), Sometimes (25%); Total = 38%

Peterson et al. [55]

USA

Adolescents diagnosed with GD

96 (AFAB = 54, AMAB = 31, Nonbinary/gender fluid = 15

12–22 year-old, x̄ = 17.1 ± 2.3

Suicide attempts; self-injurious behaviours

Descriptive statistics

χ²

N (%)

History of suicide attempt = 27 (30.3%)

History of self-injurious behaviours = 40(41.8%)

Depressive disorder (n = 36, 38%)

Generalized anxiety disorder (n = 15, 16%)

Significant difference for AFAB reporting more suicide attempt and self-harm compared with AMAB respectively:

(χ² = 9.38, p < 0.05; χ² = 8.73, p < .05)

H. K. Mitchell et al. [56]

USA

TNB adolescents referred for GD

798,994

13–20 year old

Suicidality; self-harm; suicidality and self-harm combined

Multivariable Poisson regression models

2016 cohort OR [95% CI]

Association with suicidality Unadjusted 6.19 [5.80 to 6.60]; Adjusted 3.80 [3.52 to 4.10]

Association with self-harm Unadjusted 3.80 [3.13 to 4.61]; Adjusted 2.68 [2.17 to 3.30]

Association with suicidality or self-harm Unadjusted 5.71 [5.30 to 6.06]; Adjusted 3.59 [3.35 to 3.85]

2019 cohort OR [95% CI]

Association with suicidality Unadjusted 4.71 [4.58 to 4.85]; Adjusted 3.23 [3.12 to 3.34]

Association with self-harm Unadjusted 4.21 [3.85 to 4.61]; Adjusted 2.90 [2.62 to 3.21]

Association with suicidality or self-harm Unadjusted 4.58 [4.46 to 4.69]; Adjusted 3.15 [3.06 to 3.25]

Karvonen et al. [57]

Finland

Gender-referred adolescents (GR) and adolescents mental health referred (MHR)

GR = 84

MHR = 293

GR x̄ = 16.2 ± 1.3

MHR x̄ = 15.6. ± 1.6

p = 0.002

More birth-assigned females in the GR group than in the MHR group (84.5% vs. 64.2%, p < 0.001)

Suicidal ideation and talk, suicide attempt; self-harming behaviours

ANOVA

Suicidal ideation and talk GR = 70.2%; MHR = 50.5%; p = 0.001

OR [95% CI] Model 1 controlled for age and sex = 1.8 [1.0 to 3.1]; p = 0.04

OR [95% CI] Model 2 controlled for age, sex, family and child welfare contacts = 2.8 [1.6 to 5.2]; p = 0.001

Suicide attempt GR = 10.7%; MHR = 8.9%; p = 0.37

OR [95% CI] Model 1 controlled for age and sex = 1.0 [0.5 to 2.3]; p = 0.93

OR [95% CI] Model 2 controlled for age, sex, family and child welfare contacts = 1.1 [0.4 to 2.8]; p = 0.9

Self-harming behaviours GR = 61.4%; MHR = 39.2%; p =  < 0.001

R [95% CI] Model 1 controlled for age and sex = 1.9 [1.1 to 3.2]; p = 0.02

OR [95% CI] Model 2 controlled for age, sex, family and child welfare contacts = 2.2 [1.2 to 4.0]; p = 0.007

Depression GR = 67.9%; MHR = 59.0%; p = 0.09

OR [95% CI] Model 1 controlled for age and sex = 1.0 [0.6 to 1.7]; p = 0.97

OR [95% CI] Model 2 controlled for age, sex, family and child welfare contacts = 1.7 [0.9 to 3.0]; p = 0.1

Tordoff et al. [58]

USA

TNB adolescents

104, AMAB = 63; AFAB = 27; Nonbinary/gender fluid = 10; Questioning = 4

13–20 year old x̄ = 15.8 ± 1.6

Self-harm; suicidal thoughts

Descriptive statistics

No. (%)

Self-harm or suicidal thoughts at baseline = 45 (43.2%)

Depression at baseline 0–4 (minimal) = 14 (13.5%) 5–9 (mild) = 27 (26.0%) 10–14 (moderate) = 22 (21.2%) 15–19 (moderately severe) = 11 (10.6%) ≥ 20 (severe) = 26 (25.0%) Missing = 4 (3.8%)

Anxiety at baseline 0–4 (minimal) = 20 (19.2%) 5–9 (mild) = 28 (26.9%) 10–14 (moderate) = 20 (19.2%) 15–19 (moderately severe) = 11 (10.6%) ≥ 20 (severe) = 32 (30.8%) Missing = 4 (3.8%)