Table 1 Characteristics, outcomes and association measures of the included studies

Daviera et al., 2019 [31]

Country: USA

City: Chicago

N = 314

• Age

Average 16.17 (SD 0.79)

• Crime statistics

• Subtypes:

Trait anxiety

Pervasive CVE:

• Home-based × school-based CVE × anxiety: β = -0.69 (SE 0.33)*

Spatially proximate CVE:

• Most distal CVE × anxiety: β = -0.01 (SE 0.05)

• Most proximal CVE × anxiety: β = -0.19 (SE 0.21)

Chronic CVE:

• Long-term CVE × anxiety: β = -0.017 (SE 0.064)

• Mid-term CVE × anxiety: β = -0.031 (SE 0.070)

• Short-term CVE × anxiety: β = -0.066 (SE 0.044)

Elsaesser et al., 2018 [32]

Country: USA

City: Chicago

N = 246

• Mean age 14.8 (SD 1.2)

• Classified into victim and witness

• Subtypes: Depression

• Victim of CVE × depression (longitudinal): β = -0.03 (SE NI) *

• Witness of CVE × depression (longitudinal): β = 0.14 (SE NI)

• Victim of CVE × depression (cross-sectional): β = 0.14 (SE NI) *

• Witness of CVE × depression (cross-sectional): β = 0.08 (SE NI)

Eisman et al., 2015 [33]

Country: USA

City: Flint

N = 824

• Mean age 14.86 (SD 0.64)

• Not classified into victim and witness

• Subtypes: Depressive symptoms

• CVE × depressive symptoms: β = 0.03 (SE 0.02) *

Farrell et al., 1997 [34]

Country: USA

City: Richmond

N = 436

• Mean age 11.7 (SD 0.6)

• Not classified into victim and witness

• Subtypes:

Emotional distress

• CVE × emotional distress (male): β = 0 (SE NI)

• CVE × emotional distress (female): β = 0.07 (SE NI)

Gepty et al., 2019 [35]

Country: USA

City: Philadelphia

N = 309

• Age

Average 12.9 (SD 0.61)

• Crime statistics

• Subtypes:

Depression

• CVE × rumination × depression: β = 0.0004 (SE NI) *

• No CVE × rumination × depression: β = -0.0001 (SE NI)

• Violent crime × rumination × depressive symptoms: β =0.0002 (SE 0.00)*

•Nonviolent crime × rumination × depressive symptoms: β =0.00 (SE 0.00)

Kohl et al., 2015 [36]

Country: USA

City: Chicago

N = 320

• Mean age 11.65 (SD 0.7)

• Not classified into victim and witness

• Subtypes: Depression

• CVE 6th grade × Depression 7th grade: β = 0.15 (SE NI) *

• CVE 7th grade × Depression 8th grade: β = 0.21 (SE NI) *

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

Lambert et al., 2008 [37]

Country: USA

N = 473

• Mean age 11.77 (SD 0.35)

• Not classified into victim and witness

• Subtypes: Depression

• CVE × depression (male): β = 0.20 (SE NI) *

• CVE × depression (female): β =0.20 (SE NI) *

Latzman et al., 2005 [38]

Country: USA

N = 8939

• Mean age 15.18 (SD 1.6)

• Not classified into victim and witness

• Subtypes: Depression

• CVE × depression: β = 0.02 (SE 0.03) *

McKelvey et al., 2015 [39]

Country: USA

City: Boston

N = 473

• Mean age 18 (SD NI)

• Not classified into victim and witness

• Subtypes:

Internalizing symptoms

• CVE × internalizing symptoms: β = 0.02 (SE 0.01)

• CVE × Gender × internalizing symptoms: β = -0.03 (SE 0.01)

• CVE × Gender × cohesion × internalizing symptoms: β = 0.11 (SE 0.01) *

Mrug et al., 2010 [40]

Country: USA

City: Birmingham

N = 603

• Mean age 13.20 (SD 0.9)

• Classified into victim and witness

• Subtypes: Depression, Anxiety

• Victim of CVE × depression: β = 0.01 (SE NI)

• Witness of CVE × depression: β = 0.6 (SE NI)

• Victim of CVE × anxiety: β = 0.01 (SE NI)

• Witness community × anxiety: β = 0.06 (SE NI)

Ozer et al., 2005 [41]

Country: USA

N = 73

• Age not specified numerically (7th-8th grade)

• Not classified into victim and witness

• Subtypes: Depression, Anxiety,

Intrusive symptoms

• Exposure to CVE × anxiety: β = 0.31 (SE NI)*

• Exposure to CVE × intrusive symptoms: β = 0.34 (SE NI)*

• Exposure to CVE × depression: β = 0.12 (SE NI)

Sun et al., 2020 [42]

Country: USA

N = 85

• Mean age 15.55 (SD 1)

• Not classified into victim and witness

• Subtypes:

PTSD

• CVE × PTSD: β = 0.34 (CI 0.16-0.52)*

• CVE × emotional regulation (internally dysfunctional): β = 0.2 (CI 0.06–0.35)*

• CVE × emotional regulation (externally functional): β = 0.05 (CI -0.12–0.22)

• CVE × emotional regulation (internally functional): β = 0.09 (CI -0.05–0.24)

• CVE × emotional regulation (externally dysfunctional): β = 0.11 (CI -0.06–0.27)

Aisenberg et al., 2008 [43]

Country: USA

City: Los Angeles

N = 137

• Mean age 12.41 (SD 0.79)

• Not classified into victim and witness

• Subtypes: PTSD

• CVE × PTSD: β = 4.41 (SE 2.81)

Bacchini et al., 2011 [44]

Country: Italy

City: Naples

N = 489

• Mean age 17.53 (SD 1.24)

• Classified into victim and witness

• Subtypes: Anxiety, Depression

• Victim of CVE × anxiety/depression: β = 0.25 (SE NI) *

• Victim of CVE × gender × anxiety/depression: β = 0.15 (SE NI) *

• Witness of CVE × anxiety/depression: β = 0.8 (SE NI)

• Witness of CVE × parental monitoring × anxiety/depression: β = -0.13 (SE NI) *

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

Campo-Ríos et al., 2020 [45]

Country: Mexico

City: Ciudad Juárez

N = 298

• Mean age 19.28 (SD 0.5)

• Contextual violence in neighbourhood (heard about). Victim and witness not measured

• Subtypes:

PTSD

• CVE × PTSD × female: β = 0.14 (SE NI)*

• CVE × PTSD × male: β = 0.12 (SE NI)*

• CVE × PTSD: β = 0.14 (SE NI)*

Cecil et al., 2014 [46]

Country: England

City: London

N = 204

• Mean age 18.85 (SD 2.27)

• Not classified into victim and witness

• Subtypes: PTSD Internalizing symptoms

• CVE × internalizing problems: β = 0.01 (CI -0.21-0.56)

• CVE × PTSD: β = 0.10 (CI 0.04-0.17) *

Chen et al., 2020 [47]

Country: USA

City: Chicago

N = 2621

• Age

Average 12.47 (SD 0.98)

• Not classified into victim and witness

• Subtypes:

Depression

• Latinx × CVE × depression: β = 0.48 (SE 0.07)*

• Black × CVE × depression: β = 0.50 (SE 0.08)*

• White × CVE × depression: β = 0.77 (SE 0.06)*

Cuartas et al., 2019 [48]

Country: Colombia

City: Bogotá

N = 300

• Mean age 14.52 (SD 1.72)

• Crime statistics

• Subtypes:

Common mental disorders

PTSD

• CVE (homicide rates) × common mental disorders β = 0.17 (SE 0.06)*

• CVE (homicide rate) × perceived the neighbourhood as unsafe × common mental disorders:

β = 0.23 (SE 0.07)*

• CVE (homicide rate) × perceived the neighbourhood as safe × common mental disorders:

β = -0.24 (0.13)

• CVE (homicide rates) × PTSD: β = 0.14 (SE 0.06)*

• CVE (homicide rates) × poverty × PTSD: β = 0.55 (SE 0.13)*

• CVE (homicide rates) × victim of crime × PTSD: β = 0.45 (SE 0.12)*

• CVE (homicide rates) × perceived neighbourhood as unsafe × PTSD:

β = 0.20 (SE 0.07)*

• CVE (homicide rates) × perceived neighbourhood as safe × PTSD:

β = -0.19 (SE 0.10)*

Darawshy et al., 2018 [49]

Country: Israel

N = 760

• Mean age 16.1 (SD 1.27)

• Not classified into victim and witness

• Subtypes: Internalizing symptoms

• CVE × internalizing symptoms: β = 1.74 (SE 0.28) *

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

Donernberg et al., 2020 [50]

Country: South Africa

N = 120

• Age

Average 14.39 (SD 1.82)

• Not classified into victim and witness

• Subtypes:

Internalizing symptoms

• Witness of CVE × internalizing symptoms × girls: β = -0.06 (SE 0.14)

• Witness of CVE × internalizing symptoms × boys: β = -0.03 (SE 0.14)

Ford et al., 2010 [51]

Country: USA

N = 4023

•Age 12-17 years (SD NI)

• Classified into victim and witness

• Subtypes: Depression PTSD

• Victim of CVE × PTSD: OR = 5.58 (CI 3.29–9.45) *

• Victim of CVE × depression: OR = 2.61 (CI 1.64–4.16) *

• Witness of CVE × PTSD: OR = 3.64 (CI 2.35–5.64) *

• Witness of CVE × depression: OR = 2.55 (CI 1.80–3.61) *

Foster et al., 2004 [52]

Country: USA

N = 146

• Mean age 13.16 (SD 1.01)

• Classified into victim and witness

• Subtypes: Depression Anxiety PTSD

• Victim of CVE × anxiety: β = 0.31 (SE NI) *

• Victim of CVE × depression: β = 0.14 (SE NI) *

• Victim of CVE × PTSD: β = 0.33 (SE NI) *

Goldman-Mellor et al., 2016 [53]

Country: USA

N = 4462.

• Mean age 14.6 (SD 0.22)

• Crime statistics

• Subtype: Psychological distress/depression and anxiety symptoms

• Exposure to CVE × psychological distress/depression and anxiety symptoms: OR = 1.41 (CI 0.6–3.32)

Grinshteyn et al., 2018 [54]

Country: USA

N = 5519

• Maximum age 18,

minimum age 11

• Classified into victim and witness

• Crime statistics

• Subtypes: Depressive symptoms Internalizing symptoms

• Victim of CVE (violent crime) × depressive symptoms: β = 5.13 (SE NI)*

• Seeing/knowing victim of CV (violent crime) × depressive symptoms: β = 3.46 (SE NI) *

• Witness of CVE (violent crime) × depressive symptoms: β = 2.09 (SE NI)*

• Increased of 1 crime/1000 people × depressive symptoms: β = 0.06 (SE NI) *

Haj-Yahia et al., 2021 [55]

Country: Israel

City: Jerusalem

N = 1930

• Mean age 16.36 (SD 1.04)

• Not classified into victim and witness

• Subtypes:

Internalized problems

• Witness of CVE × internalizing problems: β = 0.17 (SE NI)*

• Victmim of CVE × internalizing problems: β = -0.04 (SE NI)

• Witness of CV × female gender × internalizing problems: β = -0.09 (SE NI)

• Victim of CVE × female gender × internalizing problems: β = 0.25 (SE NI)*

• Witness of CVE × family support × internalizing problems: β = 0 (SE NI)

• VCV × family support × internalizing problems: β = 0 (SE NI)

Henry et al., 2015 [56]

Country: USA

N = 106

• Mean age 15.41 (14-17)

• Not classified into victim and witness

• Subtypes: Depressive symptoms

• CVE × depressive symptoms: β = 0.23 (SE 0.07) *

• CVE × cultural appreciation of legacy × depressive symptoms: β = -0.11 (SE 0.3) *

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

Ho et al., 2010 [57]

Country: China

City: Hong Kong

N = 405

• Mean age 13.59 (SD 1.43)

• Classified into victim and witness

• Subtypes: Emotional problems

• Witness of CVE × emotional problems: β = -0.09 (SE NI)

• Victim of CVE × emotional problems: β = 0.17 (SE NI) *

Howard et al., 2010 [58]

Country: USA

N = 174

• Age: 9th grade

• Not classified into victim and witness

• Subtypes:

Anxiety/Stress

• CVE × distress symptoms: β = 0.35 (SE NI) *

• CVE × family support × distress symptoms: β = -0.27 (SE NI)*

Kaminer et al., 2013 [59]

Country: South Africa

City: Cape Town

N = 230

• Mean age 17.45 (SD 1.59)

• Classified into victim and witness

• Subtypes: PTSD

• Victim of CVE × PTSD: β = 0.77 (SE 0.28) *

• Victim of CVE × PTSD (girls): β = 0.88 (SE 0.33) *

• Witness of CVE × PTSD: β = 0.13 (SE 0.12)

• Witness of CVE × PTSD (girls): β = 0.04 (SE 0.15)

Klodnick et al., 2014 [60]

Country: Israel

N = 1571

• Mean age 16.26 (SD 1.05)

• Classified into victim and witness

• Subtypes: PTSD

• Victim of CVE × PTSD: β = 4.91 (SE 0.49) *

• Witness of CVE × PTSD: β = 1.86 (SE 0.28) *

• Ethnicity × CVE × PTSD: β = -0.99 (SE 0.85)

Lätsch et al., 2016 [61]

Country: Switzerland

N = 6749

• Mean age 15.5 (14-17)

• Not classified into victim and witness

• Subtypes:

Emotional symptoms

• CVE × emotional symptoms: β = 0.16 (SE NI) *

Leblanc et al., 2011 [26]

Country: USA

N = 90

• Mean age 16.4 (SD 1.37)

• Not classified into victim and witness

• Subtypes:

Psychological distress

• CVE × Psychological distress: β = 0.02 (SE NI)

• CVE × Problem solving ability of adolescents × Psychological distress: β = 0.43 (SE NI)*

Mendelson et al., 2010 [62]

Country: USA

City: Baltimore

N = 629

• Mean age 18.7 (SD 1.77)

• Not classified into victim and witness

• Subtype: Depressive symptoms

• CVE × depressive symptoms: OR= 2.27 (CI 1.57–3.29)*

O’Donnell et al., 2011 [63]

Country: Republic of the Gambia

N = 653

• Mean age 17.76 (SD 1.53)

• Classified into victim and witness

• Subtypes: TEPT

• Witness of CVE × PTSD: β = 0.18 (SE 0.10)*

• Witness of CVE × school climate × PTSD: β = -0.10 (SE 0.04)*

• Victim of CVE × PTSD: β = 0.12 (SE 0.13) *

• Victim of CVE × school climate × PTSD: β = 0.12 (SE 0.5)*

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

O’Leary et al., 2020 [64]

Country: USA

N = 196

• Mean age 12.41 (SD 1.14)

• Not classified into victim and witness

• Subtypes:

PTSD

depression

• CVE × PTSD: β = 0.4 (SE 0.07)*

• CVE × cognitive reappraisal × PTSD: β = -0.1 (SE 0.1)

• CVE × expressive suppression × PTSD: β = 0.4 (SE 0.07)

• CVE × depression: β = 0.33 (SE 0.04)*

• CVE × cognitive reappraisal × depression: β = -0.08 (SE 0.05)

• CVE × expressive suppression × depression: β = 0.14 (SE 0.04)*

•Gender was tested as modifier and was not significant.

Ozer et al., 2004 [65]

Country: USA

City: California

N = 349

• Median age 12 (SD NI)

• Not classified into victim and witness

• Subtypes: Depressive symptoms PTSD

• CVE × depressive symptoms: β = 0.11 (SE NI)*

• CVE × PTSD: β = 0.19 (SE NI)*

Plessis et al., 2015 [66]

Country: South Africa

City: Cape Town

N = 616

• Mean age 12.8 (SD 0.74)

• Classified into victim and witness

• Subtypes: Depression

•Witness of CVE × depression: β = 0.02 (SE 0.04)

• Victimof CVE × depression: β = 0.07 (SE 0.14)

Sargent et al., 2019 [67]

Country: USA

N = 403

• Mean age 12.63 (SD 0.99)

• Classified into victim and witness

• Subtypes:

Depression

PTSD

Anxiety

• Victim of CVE × depression: β = 0.49 (SE NI)*

• Witness of CVE × depression: β = 0.31 (SE NI)*

• Victim of CVE × anxiety: β = 0.54 (SE NI)*

• Witness of CVE × anxiety: β = 0.50 (SE NI)*

• Victim of CVE × PTSD: β = 0.61 (SE NI)*

• Witness of CVE × PTSD: β = 0.53 (SE NI)*

Shukla et al., 2015 [68]

Country: USA

N = 233

• Mean age 17 (SD 0.62)

• Classified into victim and witness

• Subtype: Depression

• Witness of CVE × depression: β = 0.03 (SE 0.15)

• Victim of CVE × depression: β = -0.04 (SE 0.27)

Boney-McCoy et al., 1995 [69]

Country: USA

N = 2000

• Mean age 8 (10-16)

• Not classified into victim and witness

• Subtypes: PTSD Sadness

• Aggravated assault × PTSD (female): β = 0.42 (SE 2.81) *

• Simple assault × PTSD (female): β = 0.20 (SE NI)

• Attempted kidnapping × PTSD (female): β = 0.51 (SE NI)*

• Aggravated assault × PTSD (male): β = 0.36 (SE NI)*

• Simple assault × PTSD (male): β = 0.12 (SE NI)

• Attempted kidnapping × PTSD (male): Β = 0.035 (SE NI)*

Sui et al., 2018 [70]

Country: South Africa

N = 1574

• Mean age = 16 (12-22)

• Classified into victim and witness

• Subtype: Depression

• Witness of CVE × depression: β = 0.03 (SE 0.15)

• Victim of CVE × depression: β = -0.04 (SE 0.27)

Authors and year of publication

Country and city

Sample characteristics (number and age [years] of participants)

Types of CV exposure and outcome

Association measure, confidence interval or standard error, P value

Velez-Gomez et al., 2013 [71]

Country: Colombia

City: Medellín

N = 289

• Mean age 10.17 (SD 1.25)

• Crime statistics

• Subtypes: Negative mood, Interpersonal problems, Ineffectiveness, Negative self-esteem

• CVE × ineffectiveness: β = 0.21 (SE NI) *