Introduction
Method
Search Strategy and Selection Criteria
Eligibility Criteria
Study Selection
Data Extraction and Synthesis
Quality Assessment
Results
Study Characteristics
Author (year); country | Study design | Sample source | Representative (Y/N) | Sample size (% female) | Age range in years (M, SD) | Self-harm measure(s) (time period) | Motivation measure(s) | Correlates (measure) |
---|---|---|---|---|---|---|---|---|
Abbasian et al. (2021); Iran | Cross-sectional | High school students | N | 604 (100%) NSSI subsample: 160 (100%) | Overall sample: 14–17 (M = 14.3, SD = 1.1) NSSI sample: 14–17 (M = 14.3, SD = 1.1) | ISAS (lifetime) | ISAS | - NSSI severity (ISAS, DSM-5) |
Ammerman et al. (2021); USA | Cross-sectional | University students | N | 977 (83%) | 18–47 (M = 20.1, SD = 2.7) | ISAS (lifetime) | ISAS | - NSSI disclosure (non-validated measures, e.g. “Have you disclosed, or told someone, about your behavior?”) |
Andrei et al. (2024); Romania | Case series | Inpatient sample | N | 100 (80%) | 13–17 (M = 14.9, SD = 1.5) | NSSI-AT –Romanian version (lifetime) | NSSI-AT—Romanian version | - Gender |
Andrewes et al. (2017); Australia | EMA | Clinical (BPD) sample | N | 107 (83.2%) NSSI subsample: 24 (87.5%) | Overall sample: 15–25 (M = 18.1, SD = 2.7)NSSI sample: 15–25 (M = 18.2, SD = 2.9) | Parasuicidal Behaviours subscale of the BPD-SI (3 months) | Non-validated measure | N/A |
Armiento et al. (2014); Canada | Cross-sectional | University students | N | 836 (71%) NSSI subsample: 268 (70.3%) | Overall sample: range NR (M = 19.2, SD NR) NSSI sample: M = 19.1 (SD and range NR) | ISAS (lifetime), SBQ-R (12 months) | ISAS | - NSSI disclosure (non-validated measure; “Have you told anyone that you self-harm?” |
Babcock Fenerci et al. (2022); USA | Cross-sectional | Inpatient sample Control participants: community | N | 124 NSSI subsample: 49 (79.6%) | Overall sample: 13–17 NSSI sample: M = 14.9, SD = 1.3 | SITBI (lifetime) | SITBI | - History of maltreatment (CTQ) |
Bahali et al. (2024); Turkey | Cross-sectional | Inpatient sample Control participants: community | N | 106 (70%) NSSI subsample: 50 (82%) | Overall sample: 14–18 (M = 15.3, SD = 0.9) NSSI subsample: 14–18 (M = 15.6, SD = 1.1) | ISAS (lifetime) | ISAS | - Parental relationships (PBI) - Suicidality (attempts) - Trauma (CTQ-28) |
Barreto Carvalho et al. (2017); Portugal | Cross-sectional | High school students | Y | 1763 (52.9%) NSSI subsample: 521 (53.2%) | Overall sample: 14–22 (M = 16.8, SD = 1.31) NSSI sample: 14–22 (M = 16.5, SD = 1.2) | ISSIQ-A (lifetime) | ISSIQ-A | N/A |
Batejan et al. (2015); USA | Cross-sectional | University students | N | 367 (73%) NSSI subsample: 207 (minor NSSI: 67.6%; moderate/severe NSSI: 83.3%) | Overall sample: 17–45 (M = 20.6, SD = 3.1) Minor NSSI sample: 18–37 (M = 20.6, SD = 3.1) Moderate/severe NSSI sample: 18–45 (M = 20.4, SD = 3.4) | ISAS (lifetime) | ISAS | - NSSI severity (ISAS) |
Bentley et al. (2014); USA | Cross-sectional | University students | N | 150 (71.3%) | 18–24 (M = 18.8, SD = 1.0) | ISAS (lifetime) | ISAS | - Experiential avoidance (MEAQ) - Depression (ODSIS) - Anxiety (OASIS) |
Braga and Gonçalves (2014); Portugal | Cross-sectional | University students | N | 518 (67.0%) NSSI subsample: 84 | Overall sample: 17–62 (M = 20.9, SD = 6.1) Self-injurer sample: M = 19.5 (SD and range NR) | SIQ-TR (lifetime) | SIQ-TR | N/A |
Brausch et al. (2016); USA | Study 1 = cross-sectional Study 2 = case series | Study 1: University students Study 2: inpatient sample | N | Study 1: 2950 (71.2%) NSSI threshold subsample: 105 NSSI subthreshold subsample: 115 Study 2: 1082 (88.1%) NSSI threshold subsample: 539 NSSI subthreshold subsample: 543 | Study 1: Overall sample: Range NR (M = 20.4, SD = 3.0) Study 2: Overall sample: 12–57 (M = 17.4, SD = 6.7) Age of NSSI subsamples NR | Study 1: SITBI—short form (lifetime) and ISAS (lifetime) Study 2: ABASI (past year) & ISAS (lifetime) | ISAS | - NSSI frequency (SITBI, ISAS, ABASI) |
Brausch and Muehlenkamp (2018); USA | Cross-sectional | University students | N | 264 (84%) | 18–35 (M = 19.1, SD = 1.8) | SITBI (lifetime) | Modified ISAS Section II | - Effectiveness of NSSI in achieving function (modified ISAS) - NSSI versatility (SITBI) - NSSI frequency (SITBI) - Suicidality (ideation, plans, attempts; SITBI) |
Calvete et al. (2015); Spain | Cross-sectional | High school and vocational school students | N | 1864 (51.4%) NSSI subsample: 999 (58%) | Overall sample: 12–19 (M = 15.3, SD = 2.0) Age of NSSI subsample NR | FASM (past year) | FASM | - Gender (demographic questionnaire) |
Carranza et al. (2022); Canada | Cross-sectional | University students | N | 1018 (70%) NSSI subsample: 246 | Range NR (M = 19.8, SD = 3.0) Age of NSSI subsample NR | ISAS (lifetime) | ISAS | - Presence of interpersonal violence (CTS2) |
Carvalho et al. (2023a); Portugal | Cross-sectional | High school students | Y | 7918 (53.3%) NSSI subsample: 1815 (56.4%) | Overall sample: 13–19 (M = 15.5, SD = 1.7) Age of NSSI subsample NR | ISSIQ-A (timeframe NR) | ISSIQ-A | - Age - Early memories of warmth and safeness (EMWSS-A) -—Gender |
Carvalho et al. (2023b); Portugal | Cross-sectional | High school students | Y | 7918 (53.3%) NSSI subsample: 1815 (56.4%) | Overall sample: 13–19 (M = 15.5, SD = 1.7) Age of NSSI subsample NR | ISSIQ-A (timeframe NR) | ISSIQ-A | - Parental care (CECA-Q) - Emotion regulation - Trauma (CECA-Q) |
Case et al. (2020); USA | Cross-sectional | University students | N | 359 (NR) | Range NR (M = 20.4, SD = 3.3) | DSHI (lifetime and past year) | ISAS | - NSSI severity (DSHI) |
Christoforou et al. (2021); Australia | Cross-sectional | University students | N | 270 (84.1%) | 17–56 (M = 21.5, SD = 5.3) | ISAS (lifetime) | ISAS | - Emotion difficulties (DERS) |
Coppersmith et al. (2021); USA | EMA (aggregated data from 3 previous EMA studies) | Study 1: Outpatient sample Study 2: Community and online | N | Study 1: 7 (86%) Study 2: 15 (93%) Study 3 outside age range of interest | Study 1: M = 22 (SD and range NR) Study 2: M = 17 (SD and range of final sample NR; only initial criterion ‘12–19 years old’ is reported—prior to excluding participants) | EMA (daily) | Non-validated measure | N/A |
Costa et al. (2021); Brazil | Cross-sectional | Community | Y | 505 (49.7%) B-NSSI subsample: 196 (53.1%) n (D-NSSI) = 33 (72.7%) | Overall sample: 12–17 (M = 14.3, SD = 1.6) Age of NSSI subsample NR | FASM—Brazilian version (past year) | FASM—Brazilian version | - Presence of NSSI Disorder diagnosis (DSM-5 diagnostic criteria, FASM Brazilian version) |
Czyz et al. (2019); USA | Longitudinal/cohort study | Inpatient sample | N | 34 (76.5%) Lifetime NSSI subsample: 29 NSSI during study period: 15 | 13–17 (M = 15.5, SD = 1.4) Age of NSSI subsample NR | SITBI (lifetime) & C-SSRS (lifetime) | Non-validated measure | - Suicidality (ideation; C-SSRS) |
Czyz et al. (2021); USA | EMA (daily diary) | Inpatient sample | N | 78 (67.9%) | 13–17 (M = 15.2, SD = 1.4) | SITBI (lifetime), adapted ISAS (lifetime) | SITBI | - Suicidality (ideation; C-SSRS, measured during EMA period) |
DiCorcia et al. (2017); USA | Cross-sectional | Inpatient sample | N | 263 (59%) NSSI subsample: 193 (60%) | 13–25 (M = 18, SD = 3.5) | Adapted SITBI (lifetime) | Adapted SITBI | - Age - Anxiety (PHQ-4) - Depression (PHQ-4) - Gender - Suicidality (ideation, attempts; C-SSRS) |
Dixon-Gordon et al. (2022); Sample 1: Global (majority USA, Canada, UK & Australia) Sample 2: USA & Canada | Cross-sectional | Sample 1: Online Sample 2: Community | N | Sample 1: 155 (96.1%) Sample 2: 127 (82.7%) | Sample 1: 15–35 (M = 21.2, SD = 4.2) Sample 2: 18–35 (M = 23.8, SD = 4.9) | Sample 1: QNSSI (lifetime, past 3 months) Sample 2: DSHI (lifetime) | Sample 1 & 2: QNSSI, SASII | N/A |
Doyle (2017); Ireland | Cross-sectional | Post-primary school students | Y | 856 (48.8%) NSSI subsample: 103 | 15–17 (mode = 16; M and SD NR) | Lifestyle and Coping survey (lifetime) | Lifestyle and Coping survey | N/A |
Doyle et al. (2017); Ireland | Mixed methods | High school students | Y | 856 (48.8%) NSSI subsample: 103 (72.8%) | 15–17 (M and SD NR) | Lifestyle and Coping survey (lifetime) | Lifestyle and Coping survey | N/A |
Duarte et al. (2019); Portugal | Cross-sectional | High school students | N | 411 (53.3%) Self-harm subsample: 109 | Overall: 12–19 (M = 15, SD = 1.9) Age of NSSI subsample NR | Inventory of Deliberate Self-Harm Behaviours (adapted from ISAS; lifetime) | Questionnaire of Representations About the Functions of Deliberate Self-Harm for Adolescents (adapted from ISAS) | N/A |
Cross-sectional | High school students | N | 203 (54.2%) NSSI subsample: 51 | Overall adolescent sample: 12–19 (M = 14.7, SD = 1.8) Age of NSSI subsample NR | Inventory of Deliberate Self-Harm Behaviours (lifetime) | Questionnaire of Representations about the Functions of Deliberate Self-Harm | N/A | |
Faura-Garcia et al. (2022); Spain | Cross-sectional | Secondary and/or high school students | N | 685 (60.9%) NSSI subsample: 115 (72.2%) | Overall sample: 13–18 (M = 15.9, SD = 1.1) Age of NSSI subsample NR | SITBI (lifetime) | SITBI, FASM | - Gender |
Gandhi et al. (2016); Belgium | Cross-sectional | High school students | N | 401 (51.1%) NSSI subsample: 66 (65.2%) | Overall: 14–19 (M = 16.6, SD = 1.0) Age of NSSI subsample NR | Modified SIQ-TR (lifetime) | Modified SIQ-TR | - Autonomy/identity (PSI-II) |
Gandhi et al. (2021); India & Belgium | Cross-sectional | Indian sample: University students Belgian sample: Existing datasets | N | 276 (57.2%) NSSI subsample: 55 | Indian: Range NR (M = 19.8, SD = 3.2) Belgium: Range NR (M = 20.3, SD = 2.9) Age of NSSI subsample NR | Non-validated measure (lifetime) | Adapted SIQ-TR | - Country (Indian vs. Belgian) |
García-Nieto et al. (2015); Spain | Cross-sectional | Outpatient sample | N | 267 (34.7%) NSSI subsample: 58 (38%) | Overall sample: 11–18 (M = 14.1, SD = 1.9) NSSI: 11–18 (M = 14.3, SD = 1.8) | SITBI—Spanish version (lifetime) | SITBI—Spanish version | N/A |
Gardner et al. (2021); UK | Longitudinal/cohort study | Avon Longitudinal Study of Parents and Children | N | 528 (79.9%) | Examined functions of self-harm at age 16 and 21 Repeat self-harm examined at ages 21, 24 & 25 | Non-validated measure (lifetime) | Non-validated measure | - Age - Self-harm repetition (past year frequency at follow-up) - Future suicide attempts (suicide attempts at follow-up) |
Gatta et al. (2022); Italy | Retrospective cohort study | Inpatient sample | N | 361 (69.8%) NSSI subsample: 147 | Overall sample: 1–18 (M = 13.4, SD = 3.0) NSSI sample: range NR (M = 14.8, SD = 1.2) | Hospital/clinical records (lifetime) | Hospital/clinical records | N/A |
Gholamrezaei et al. (2023); Iran | Cross-sectional | University students | N | 63 (52.4%) | Range NR (M = 22.2, SD = 2.8) | One bespoke question (lifetime) | Bespoke questionnaire adapted from HIDS, ISAS | - Anxiety - Depression (DASS-21) - NSSI characteristics (including emotions experienced after NSSI engagement, age of onset, severity, presence of pain, aloneness while engaging in NSSI; adapted HIDS and ISAS) - Gender - Suicidality (SBQ-R) |
Goddard et al. (2021); Australia | Cross-sectional | University students | N | 236 (83%) | 17–56 (M = 21.6, SD = 5.4) | ISAS (lifetime) | ISAS | - Personality traits (BFI-44) |
Gray et al. (2022); Australia | Cross-sectional | University students | N | 374 (80.7%) NSSI subsample: 210 | Overall sample: 18–52 (M = 23.6, SD = 4.2) Age of NSSI subsample NR | ISAS (lifetime) | ISAS | - NSSI status (current or stopped; ISAS) - Desire to stop NSSI (ISAS) |
Groschwitz et al. (2015); Germany | Cross-sectional | Inpatient sample | N | 111 (65.8%) NSSI disorder subsample: 41 SBD subsample: 34 (82.4%) | Overall sample: 12 -19 (M = 15.4, SD = 1.7) SBD subsample: 12–19 (M = 15.4, SD = 1.5) Age of NSSI subsample NR | SITBI-G (German version) (lifetime) | SITBI-G | N/A |
Guan et al. (2024); China | Cross-sectional | Outpatient sample | N | 412 (70.2%) | 13–18 (M = 15.0, SD = 1.6) | NSSI diagnosis by psychiatrist (timeframe NR) | ANSSIAQ | N/A |
Guérin-Marion et al. (2021); Canada | Cross-sectional | University students | N | 479 (83.8%) | 17–25 (M = 18.8, SD = 1.4) | OSI (past year, lifetime) | OSI | - Emotion regulation difficulties (DERS, DERS-positive, RTSQ) |
Güngördü and Ayaydin (2024); Turkey | Case-controlled cross-sectional study | Outpatient sample | N | 110 (68.2%) NSSI subsample: 50 (70%) | Overall sample: 13–17 (M = 15.5, SD = 1.3) NSSI subsample: 13–17 (M = 15.4, SD = 1.4) | ISAS (lifetime) | ISAS | - Gender |
Hamza et al. (2014); Canada | Experimental study | University students | N | 82 (69.5%) | M = 21.5 (SD & range NR) | ISAS (past year) | ISAS | - Pain tolerance (cold-pressor task) |
Hettiarachchi et al. (2018); Sri Lanka | Cross-sectional | Justice-involved youth | Y | 181 (28.2%) Self-harm subsample: 77 (42.9%) | Overall sample: 12–16 (M = 15.0, SD = 2) Age of NSSI subsample NR | Non-validated measure (lifetime) | Non-validated measure | N/A |
Horowitz and Stermac (2018); Canada | EMA | Community | N | 38 (89.5%) | 18–30 (M = 21.9, SD = 2.6) | ISAS (lifetime) | ISAS | - Trauma severity (TEC) |
Idig-Camuroglu and Gölge (2018); Turkey | Cross-sectional | University students | N | 1000 (69%) NSSI subsample: 285 (65.3%) | Range, M & SD NR Overall sample: 46.1% between 18–20 years, 45.1% 21–23 years old, 8.8% 24 and older | ISAS (lifetime) | ISAS | - Gender - Trauma (CTQ) |
Ilieff and Hamza (2023); Canada | Longitudinal | University students | N | 841 (71%) NSSI subsample time 1: 225 (NR) NSSI subsample time 2: 185 (NR) NSSI subsample time 3: 126 (NR) | Overall sample: 18–25 (M = 18.0, SD = 0.7) NSSI subsample: range NR (M = 18.0, SD = 0.8) | Adapted ISAS (past 4 months) | Adapted ISAS | - Trauma (PCL) |
Jiang et al. (2022); China | Cross-sectional | Junior high school students | N | 2376 (52.2%) NSSI subsample: 881 (56.6%) | Overall sample: range NR (M = 13.7, SD = 1.0) NSSI: range NR (M = 13.6, SD = 1.0) | Adolescents Self-Harm Scale (past year) | Adolescents Self-Harm Scale | N/A |
Jonsson et al. (2019); Sweden | Cross-sectional | High school students | Y | NSSI only subsample: 910 (76%) SASI only subsample: 41 (70.7%) NSSI & SASI subsample: 76 (86.8%) | Overall sample: range NR (M = 18.0, SD = 0.6) Age of NSSI subsamples NR | SITBI-SF-SR (lifetime) | FASM | - Self-injury method (sex as a form of self-injury vs. other NSSI methods) (FASM & non-validated measure: “Have you ever used sex to purposely hurt yourself?”) |
Kaess et al. (2013); Germany | Case series | Inpatient sample | Y | 125 (50.4%) NSSI subsample: 75 (57.3%) | Overall: 13–26 (M = 17.1, SD = 3.1) NSSI: 13–26 (M = 16.5, SD = 2.6) | FASM (past year) | FASM | - Adverse childhood experiences (CECA-Q) |
Kandsperger et al. (2022); Germany | Longitudinal/cohort study | Outpatient sample | Y | 97 (77.3%) NSSI subsample: 88 | 11–18 (M = 14.9, SD = 1.52) | SITBI-G (lifetime) | SITBI-G | - Emotional reactivity (ERS) |
Ke et al. (2024); China | Cross-sectional | High school students | N | 3657 (44.2%) NSSI subsample: 616 | Overall sample: 13–20 (M = 16.5, SD = 1.1) NSSI subsample: 13–20 (M = 16.6, SD = 1.1) | ANSAQ (past year) | ANSAQ | - Alexithymia (TAS-20) - Childhood maltreatment (CTQ-SF) - Help-seeking attitudes (ATSPPH-SF) |
Kharsati and Bhola (2015); India | Cross-sectional | University students | N | 470 (70%) NSSI subsample: 143 | Overall sample: range NR (M = 20.3, SD = 1.7) | FASM (past year) | FASM | - Severity of NSSI (FASM) |
Khutoryanskaya et al. (2023); Russia | Case series | Outpatient sample | N | 91 (87.9%) | 13–24 (M = 17, SD NR) | ISAS – Russian version (lifetime) | ISAS – Russian version | - Age - Gender - Mental health diagnoses (including behavioural disorders, depressive episodes and eating disorders; clinical assessment by a psychiatrist) |
Kiekens et al. (2017); USA | Longitudinal/cohort study | College students | Y | Persistent NSSI subsample: 51 (67.3%) Ceased NSSI subsample: 50 (83.7%) | Persistent NSSI: range NR (M = 20, SD = 3.0) Ceased NSSI: range NR (M = 20.3, SD = 2.4) | NSSI-AT (lifetime) | NSSI-AT | - NSSI status (ceased vs. Persistent; NSSI-AT at baseline and follow-up) |
Klonsky et al. (2015); USA | Case series | Inpatient sample | N | 1157 (89.4%) | 11–73 (M = 16.6, SD = 7.7) | ISAS (lifetime), FASM (past year) | ISAS, FASM | - Recent NSI frequency (ABUSI) - Recent NSI urge (ABUSI) |
Knorr et al. (2013); USA | Cross-sectional | University students | N | 1678 (70.5%) NSSI subsample: 359 (75.5%) | Total N: 18–27 (M = 20.4, SD = 1.6) NSSI: 18–27 (M = 20.3, SD = 1.6) | FAFSI (lifetime) | FAFSI | - Total number of NSI acts (FAFSI) - NSSI types (FAFSI) - NSSI method (FAFSI) - Sensation seeking (SSPT) - Emotional reactivity (ERS) |
Kostić et al. (2019); Serbia | Case series | Clinical sample | N | 50 (70%) | 13–18 (M = 15, SD = 1.2) | ISAS (lifetime) | ISAS | - Gender |
Kostic et al. (2024); Serbia | Case series | Inpatient sample | N | 50 (82%) | 12–18 (M = 15.4, SD = 1.4) | Hospital records (timeframe NR) | OSI | - Motivation to stop NSSI (OSI) - Suicidality (ideation; OSI) |
Kraus et al. (2020); Switzerland & Germany | Cross-sectional | Inpatient sample | N | 56 (100%) | 12–18 (M = 16.0, SD = 1.3) | Kinder-DIPS (lifetime), FASM (past year) | Kinder-DIPS, FASM | - Suicidality (ideation; Kinder-DIPS) |
Lee (2016); South Korea | Cross-sectional | Middle school students | N | 784 (48.8%) NSSI subsample: 97 | Overall sample: 13–15 (M = 14.4, SD = 1.7) Age of NSSI subsample NR | SHQ (lifetime) | SHQ | N/A |
Luo et al. (2024); China | Cross-sectional | Primary and middle school students | N | 10,501 (49.5%) NSSI subsample (NSSI 5 + times in past year): 697 (61.3%) | Overall sample: 8–18 (M & SD NR) Age of NSSI subsample NR | OSI (past year) | OSI | - Addictive features of NSSI (OSI) - Severity of NSSI (ASHS) |
Luyckx et al. (2015); Belgium | Cross-sectional | Sample 1: High school students Sample 2: Inpatient sample | Y | Sample 1: 348 (100%) NSSI subsample: 72 | Overall: range NR (M = 16.0, SD = 1.3) Age of NSSI subsample NR | SIQ-TR (lifetime) | SIQ-TR | - Identity (EPSI Identity subscale) |
Ma and Su (2023); China | Cross-sectional | Junior high school students | N | 1885 NSSI subsample: 544 | Overall sample: 11–16 (M = 13.1, SD = 0.9) NSSI subsample: 11–16 (M = 13.1, SD = 0.9) | OSI (past year) | OSI | - Gender |
Mahtani et al. (2018); Australia | Cross-sectional | University students | N | 384 (81.3%) | Range NR (M = 20.7, SD = 2.3) | ISAS (lifetime) | ISAS | N/A |
McManus et al. (2019); England, UK | Longitudinal/cohort study | Community | Y | Year 2000: 665 (NSSI subsample: 37) Year 2007: 567 (NSSI subsample: 59) Year 2014: 559 (NSSI subsample: 90) % female NR | 16–24 (M and SD NR) | Non-validated measure (lifetime) | Non-validated measure | - Gender |
Mehmood et al. (2023); Pakistan | Cross-sectional | University students | N | 386 (55.9%) NSSI subsample: 110 (45.4%) | Overall sample: 17–27 (M = 19.7, SD = 1.5) Age of NSSI subsample NR | ISAS (lifetime) | ISAS | N/A |
Mirichlis et al. (2022); Australia | Cross-sectional | University students | N | 573 (80.6%) | 17–52 (M = 23.7, SD = 6.6) | ISAS (past year) | ISAS | - NSSI disclosure (non-validated measure) |
Muehlenkamp et al. (2013); USA | Cross-sectional | University students | N | 1243 (NR) NSSI subsample: 183 (NR) | Overall: Range NR (M = 21.5, SD = 4.2) Age of NSSI subsample NR | NSSI-AT (lifetime) | NSSI-AT | - NSSI status (initiating vs. repeating; non-validated measure) |
Nagy and Muehlenkamp (2024); USA | Cross-sectional | University students | N | 468 (83.4%) | Range NR (M = 21.2, SD = 3.1) | ISAS (lifetime) | ISAS | - NSSI severity (ISAS) - Self-esteem (B-RSE) |
Nicol et al. (2022); Australia | Cross-sectional | University and high school students | N | 125 (80%) | 16–25 University students – female: M = 20.9, SD = 2.4; university students – male: M = 21.4, SD = 2.9; High school students – female: M = 16.4, SD = 0.6; high school students – male: M = 17.1, SD = 0.7 | ISAS (lifetime) | ISAS | - Age - Early maladaptive schemas (YSQ) |
Ong et al. (2017); Singapore | Cross-sectional | Clinical sample | N | 30 (60%) | Range NR (M = 16.3, SD = 1.7) | FASM (past year) | FASM | - Depression (CBCL, psychiatrist interview with diagnoses based on DSM-IV-TR) |
Park et al. (2022); Korea | Cross-sectional | Community, online | N | 614 (70.8%) NSSI subsample: 414 (NR) | NSSI subsample: 18–29 (M = 22.6, SD = 2.7) | ISAS—Korean version (lifetime) | ISAS | - Suicidality (ideation; BSSI) |
Park et al. (2024); USA | Cross-sectional | University students | N | 820 (83.3%) | Range NR (M = 20.5, SD = 9.1) | ISAS (lifetime) | ISAS | - Gender - Suicidality (SBQ-R) |
Paul et al. (2015); USA | Cross-sectional | University students | Y | 13 396 (57.1%) NSSI subsample: 1873 | 18–29 (M = 20.9–21.8, SD = 2.5–2.8) (M & SD reported separately for different groups) | NSSI-AT (lifetime) | NSSI-AT | - Suicidality (ideation, plans, attempts; non-validated screening questions) |
Pérez Rodríguez et al. (2021); Spain | Cross-sectional | Lower secondary, high school, and university students | Y | 1733 (53.3%) NSSI subsample: 431 | Overall: 12–19 (M = 15.8, SD = 1.8) NSSI: 12–19 (M = 14.9, SD = 1.7) | ISAS – Spanish version (lifetime) | ISAS | N/A |
Peters et al. (2019); USA | Baseline measures from an RCT | Inpatient sample | N | 52 (62%) NSSI subsample: 49 | 12–18 (M = 15.6, SD = 1.5) Age of NSSI subsample NR | C-SSRS (lifetime), ISAS (lifetime) | ISAS | - Sexuality (demographic questionnaire) |
Piarulli et al. (2023); Italy | Case series | Clinical sample | N | 43 (100%) | Range NR (M = 15.2, SD = 1.7) | OSI – Italian version (past year) | OSI – Italian version | - Cortisol levels (serum) - Cortisol/DHEA-S ratio (serum) |
Pollak et al. (2020); USA | Case series | Inpatient sample | N | 76 (72.3%) | 11–17 (M = 15, SD = 1.4) | SITBI (lifetime) | SITBI | - NSSI thoughts and behaviours during and after inpatient admission (SITBI) |
Radziwiłłowicz and Lewandowska (2017); Poland | Cross-sectional | Inpatient sample | N | 60 (85%) | 13–17 (M = 15.5, SD = 1.2) | ISAS – Polish version (lifetime) | ISAS | - Body image (Feelings Towards the Body Questionnaire) - Death of close person (non-validated measure) - Depression (CDI) - Dissociation (Ego-Psychopathology Scale) - Sexual abuse (non-validated measure) - Sexual violence (non-validated measure) - Suicide attempt in family (non-validated measure) |
Rasmussen et al. (2016); Northern Ireland, UK | Longitudinal/cohort study | School students | Y | 987 (57%) Self-harm subsample: 88 (75%) | Overall: 14–16 (M = 14.7, SD = .6) Age of self-harm subsample NR | Northern Ireland Lifestyle and Coping Survey (lifetime) | Northern Ireland Lifestyle and Coping Survey | - Gender - Repeat self-harm (non-validated measure) |
Reinhardt et al. (2021a); Hungary | Cross-sectional | Justice-involved youth | Y | 244 (7.4%) Lifetime NSSI subsample: 84 Past month NSSI subsample: 64 | Overall: 14–20 (M = 17.0, SD = 1.3) Age of NSSI subsample NR | SIQ-TR (lifetime) | SIQ-TR | - Age - Gender |
Reinhardt et al. (2021b); Hungary | Cross-sectional | Secondary school students | Y | 1015 (66.1%) NSSI subsample: 418 (70.6%) | Total sample: 14–20 (M = 16.8, SD = 1.4) NSSI (female): M = 16.8, SD = 1.4 NSSI (male): M = 17.0, SD = 1.5 | ISAS (parts I and II) – Hungarian version (lifetime), frequency question from the SIQ-TR | ISAS | - Age - Experiential avoidance (AFQ-Y8) - Externalising symptoms (SDQ) - Gender - Internalising symptoms (SDQ) - Loneliness (non-validated measure) - Self-critical rumination (SCRS) |
Reinhardt et al. (2022a); Hungary | Cross-sectional | Secondary school students | Y | 322 (73.2%) | 14–20 (M = 16.7, SD = 1.4) | ISAS (lifetime) | ISAS | - Discrepancy (SAPS Discrepancy subscale) - Mental health (A-MHC-SF) - Pain and aloneness during self-harm (ISAS) - Urge for and commitment to self-harm (ISAS) |
Reinhardt et al. (2022b); Hungary | Cross-sectional | Outpatient and inpatient samples | Y | 158 (83.5%) Lifetime NSSI subsample: 119 (88.2%) Past month NSSI subsample: 54 | Overall: 13–21 (M = 16.1, SD = 1.5) Lifetime NSSI: 13–21 (M = 16.1, SD = 1.6) | ISAS (lifetime) | ISAS | - Age - Co-occurring psychiatric disorders (ICD-10 codes) - Externalising symptoms (ICD-10 codes) - Gender - Internalising symptoms (ICD-10 codes) - NSSI methods (ISAS) - NSSI status (current vs. past, repetitiveness; ISAS) - Self-critical rumination (SCRS) |
Robillard et al. (2022); Canada | Longitudinal/cohort study | University students | N | 513 (78.2%) NSSI sample at each time point ranged from 10–28 | Overall sample: range NR (M = 18.0, SD = .8) Age of NSSI subsample NR | Non-validated measure (past month) | 24 items adapted from ISAS and SASII | N/A |
Robinson et al. (2021); New Zealand | Longitudinal/cohort study | Year 9 students | Y | 2057 (54.9%) NSSI subsample: 450 | 13–18 (M = 15.6, SD = 1.2) Age of NSSI subsample NR | DSHI (lifetime) | ISAS | - Suicidality (ideation and behaviours; SBQ-R) |
Rodav et al. (2014); Israel | Cross-sectional | Junior high school and high school students | Y | 275 (49.9%) NSSI subsample: 57 (42.1%) | 12–17 (M = 14.8, SD = 1.4) NSSI subsample: 12–17 (M = 15.2, SD = 1.2) | OSI-F – Hebrew version (past year) | OSI-F | N/A |
Roley-Roberts et al. (2017); USA | Cross-sectional | University students | N | 121 (78%) | 18–22 (M = 18.7, SD NR) | FASM (past year) | FASM | - Suicidality (ideation, attempts; BSSI) |
Sadeh et al. (2014); USA | Case series | Outpatient sample | N | 36 (88.6%) | 13–24 (M = 16.7, SD = 2.3) | ISAS (lifetime) | ISAS | - BPD symptoms (SCID-II) |
Saraff and Pepper (2014); USA | Cross-sectional | University students | N | 52 (84.6%) | 18–26 (M = 19.8, SD = 1.9) | ISAS (lifetime) | ISAS | - BPD symptoms (SCID-II) - Frequency of NSSI (ISAS) - Status of NSSI (past vs. Recent) (ISAS) - Variety of NSSI (ISAS) |
Saraff et al. (2015); USA | Cross-sectional | University students | N | 52 (84.6%) | 18–26 (M = 19.8, SD = 1.9) | ISAS (lifetime) | ISAS, SASII | - Consequences of NSSI (SASII) - Frequency of NSSI (ISAS) |
Schmidt et al. (2023); Spain | Cross-sectional | College students, inpatient sample and online | N | 86 (NR) NSSI subsample = 25 (84%) NSSI & BPD subsample = 30 (90%) Healthy controls = 31 (83.9%) | Overall sample: 18–33 NSSI subsample: (M = 20.9, SD = 1.4) NSSI & BPD subsample: (M = 23.6, SD = 4.2) Healthy controls: (M = 23.3, SD = 4.2) | ISAS (lifetime) | ISAS | - Borderline personality disorder diagnosis (SCID-II) - Emotion regulation (DERS-18) - Impulsivity (UPPS-P) |
Selby et al. (2014); USA | EMA | Clinical sample | N | 30 (86.7%) | 12–19 (M = 17.3, SD = 1.9) | Baseline: SITBI (lifetime) EMA: non-validated questions (current) | Non-validated questions asked during EMA | - Age - Dysregulated behaviours (non-validated questions during EMA) - Gender - Impulsiveness of NSSI (non-validated question during EMA) - NSSI frequency (lifetime; SITBI) - Presence of NSSI thoughts/behaviours during EMA (non-validated questions) - Psychiatric disorders (K-SADS) |
Shahwan et al. (2018); Singapore | Cross-sectional | Outpatient sample | N | 400 (48.8%) Self-harm subsample: 235 | 14–35 (M = 23.3, SD = 6.0) Age of self-harm subsample NR | FASM (past year) | FASM | N/A |
Shen et al. (2023); China | Case series | In- and outpatient sample | N | 1101 (81.9%) | 12–18 (M = 14.7, SD = 1.6) | C-FASM (past year) | C-FASM | - Age - Gender - NSSI characteristics (including frequency, methods, duration; C-FASM) - Suicidality (past year attempts; non-validated questions) |
Shi et al. (2023); China | Cross-sectional | University students | N | 1339 (50.3%) NSSI subsample: 116 (50.9%) | Overall sample: 16–29 (M = 19.9, SD = 1.3) NSSI subsample: range NR (M = 19.9, SD = 1.4) | OSI – Chinese version (lifetime) | OSI – Chinese version | - Early maladaptive schemas (YSQ-SF) |
Shingleton et al. (2013); USA | EMA | Adolescents who reported engaging in NSSI within the past two weeks | N | 30 (87%) | 12–19 (M = 17, SD = 1.9) | Baseline: K-SADS (present/lifetime), SITBI (lifetime) EMA: non-validated measures (current) | EMA: non-validated question | N/A |
Silverman et al. (2018); USA | Cross-sectional | Justice-involved youth | N | 103 (0%) Lifetime NSSI subsample: 68 High-frequency NSSI subsample: 22 | 13–18 (M = 15.7, SD = 1.1) Age of NSSI subsample NR | DSHI (lifetime) | FDSHA | - Alienation or boredom (APS) - Emotional lability (APS) - Problems with interpersonal relationships (APS) |
Szewczuk-Bogusławska et al. (2021); Poland | Mixed method | Inpatient (conduct disorder) sample | N | 215 NSSI subsample: 77 (74%) | Lifetime NSSI subsample: range NR (M = 14.6, SD = 1.1) | Non-validated measure (lifetime) | ISAS – Polish version | - NSSI frequency (non-validated measure) - Suicidality (attempts; non-validated measure) |
Tan et al. (2014); Singapore | Mixed methods | Outpatient sample | N | 60 (60%) NSSI subsample: 30 | NSSI: 13–19 (M = 16.3, SD = 1.7) Control: 13–19 (M = 16.0, SD = 1.7) | FASM (past year) | FASM | N/A |
Taş Torun et al. (2022); Turkey | Cross-sectional study | Clinical (depression) sample | N | 67 (83.6%) NSSI subsample: 43 | Girls: 11–17 (M = 14.9, SD = 1.5) Boys: 11–17 (M = 14.7, SD = 1.5) Age of NSSI subsample NR | ISAS (lifetime) | ISAS | - Anxiety (BSI) - Childhood physical abuse (CTQ) - Difficulty identifying feelings (TAS-20) - Emotional neglect (CTQ) - Impulsivity (DERS) - Lack of clarity in emotional response (DERS) - Paranoid ideation (BSI) - Obsessive compulsion (BSI) |
Thai et al. (2021); Vietnam | Cross-sectional | High school students | N | 1316 (63.3%) NSSI subsample: 551 (61.7%) | Range 15–18 (M & SD NR | FASM (past year) | FASM | - NSSI severity (FASM) |
Vega et al. (2017); Spain | Cross-sectional | University students & clinical (BPD) patients | N | 274 NSSI subsample: 75 (60.3%) NSSI + BPD subsample: 36 (91.7%) | NSSI-: 18–30 (M = 21.6, SD = 3.5) NSSI + : 18–30 (M = 21.4, SD = 3.2) BPD + NSSI: 18–30 (M = 22.7, SD = 3.5) | ISAS – Spanish version (lifetime) | ISAS | - BPD diagnosis and symptoms (diagnosis based on DSM-IV-TR and DIB-R, symptoms measured using MSI-BPD – Spanish version, BPQ) |
Vergara et al. (2023); USA | Case series | Inpatient sample | N | 70 (73.6%) | 12–17 (M = 14.7, SD = 1.5) | SHBQ (lifetime), ISAS (lifetime) | ISAS | - Suicidality (attempt; SHBQ) |
Verroken et al. (2018); Belgium | Cross-sectional | School students (refugee minors aged 14 to 18) | Y | 121 (39.7%) Past-year self-harm subsample: 17 Lifetime self-harm subsample: 21 (47.6%) | Total sample: 14–18 (M = 16.1, SD = 1.2) | Screeningsvragenlijst opzettelijk zelfverwondend gedrag (screening questionnaire based on BNSSI-AT) (lifetime) | Screeningsvragenlijst opzettelijk zelfverwondend gedrag | N/A |
Victor et al. (2015); USA | Case series | Inpatient, partial hospitalisation and outpatient sample | N | 1502 (87.7%) | 11–25 (M = 16.4, SD = 2.6) | ABASI (lifetime/past year/past week) | ISAS-SF | - Suicidality (ideation; BASIS-24) |
Victor and Klonsky (2018); USA | Cross-sectional | High school students | N | 89 (67.4%) | 13–17 (M & SD NR) | Non-validated measure (lifetime) | SITBI | - Knowledge of friends’ NSSI (non-validated measure) |
Wachter Morris and Wester (2020); USA | Cross-sectional | High school students | N | 218 (45.5%) Self-harm subsample: 68 (though analyses of interest only conducted on n = 38) | 12–18 (M = 15.4, SD = 1.5) Age of self-harm subsample NR | DSHI-A (lifetime) | FASM | - Suicidality (suicidal behaviours; non-validated measures) - Size of peer network (non-validated measure) - Strength of friendships (non-validated measure) |
Wang et al. (2022); China | Case series | Outpatient sample | Y | 658 (84.4%) | 12–18 (M = 15.1, SD = 1.7) | C-FASM (past year) | FASM | N/A |
Wang et al. (2024); China | Cross-sectional | College students | N | 5281 (67.5%) DiSH only subsample: 488 (78.7%) PSH only subsample: 195 (72.8%) DiSH and PSH subsample: 84 (79.8%) | Range NR Overall sample: (M = 20.8, SD = 2.7) DiSH only subsample: (M = 20.3, SD = 1.8) PSH only subsample: (M = 20.0, SD = 1.8) DiSH and PSH subsample: (M = 20, SD = 1.7) | Bespoke (lifetime) | FASM and bespoke item | - Anxiety (GAD-7) - Depression (PHQ-9) - Method of NSSI (non-validated measure) - Suicidality (ideation, plans, attempts; non-validated measure) |
Westers et al. (2014); USA | Cross-sectional | Outpatient sample | Y | 30 (70%) | 12–19 (M & SD NR) | SITBI – NSSI section (lifetime) | SITBI – NSSI section | - Religious coping (Brief RCOPE) - Religiousness (DRI) |
You et al. (2013); Hong Kong | Longitudinal/cohort study | High school students | Y | Wave 1: 5423 (52.7%) NSSI subsample: 1014 | Wave 1: 12–18 (M = 14.6, SD = 1.3) Age of NSSI subsample NR | Wave 1: non-validated measure (past year) | Adapted version of FASM | - Gender - NSSI severity (moderate/severe NSSI vs. minor NSSI based on method) |
You et al. (2015); Hong Kong | Cross-sectional | High school students | N | 42 (76.2%) | 14–18 (M = 15.6, SD = 1.1) | ISAS (past 12 months) | SASII | - Self-harm method (SASII) |
Zetterqvist et al. (2013); Sweden | Cross-sectional | High school students | Y | 3060 (50.5%) NSSI subsample: 1088 (56.2%) | 15–17 (M & SD NR) | FASM – Swedish version (past year) & SITBI-SF-SR – Swedish version (lifetime/past year/past month/past week) | FASM | - Gender - NSSI Disorder diagnosis (FASM, SITBI-SF-SR & non-validated diagnostic questions) |
Zetterqvist et al. (2014); Sweden | Cross-sectional | Community sample | Y | 816 (56.7–57.0%; range is due to missing data on gender) | 15–17 (M & SD NR) | FASM – Swedish version (past year) | FASM | - Anxiety (TSCC) - Dissociative symptoms (TSCC) - Emotional abuse (LYLES) - Gender - NSSI Frequency (FASM) - Physical abuse (LYLES) - Prolonged illness or handicap during upbringing (LYLES) - Sexual abuse (LYLES) - Suicide attempt (item from SITBI-SF-SR – Swedish version) |
Zhang et al. (2019); China | Cross-sectional | Junior high school students | Y | 510 (56.7%) | 12–16 (M = 13.5, SD = 1.0) | OSI (past month/past 6 months/past year) | OSI | N/A |
Zhao et al. (2024); China | Cross-sectional | Inpatient sample | N | 1773 (82.2%) | 12–18 (female M = 14.76, SD = 1.65; male M = 15.29, SD = 1.52) | C-FASM (past year) | C-FASM | - Anxiety (GAD-7) - Gender - NSSI frequency (C-FASM) |