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Mental disorder, psychological problems and terrorist behaviour: A systematic review and meta‐analysis

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  • Kiran M. Sarma
  • Sarah L. Carthy
  • Katie M. Cox

Abstract

Background The link between mental health difficulties and terrorist behaviour has been the subject of debate for the last 50 years. Studies that report prevalence rates of mental health difficulties in terrorist samples or compare rates for those involved and not involved in terrorism, can inform this debate and the work of those responsible for countering violent extremism. Objectives To synthesise the prevalence rates of mental health difficulties in terrorist samples (Objective 1—Prevalence) and prevalence of mental health disorders pre‐dating involvement in terrorism (Objective 2—Temporality). The review also synthesises the extent to which mental health difficulties are associated with terrorist involvement compared to non‐terrorist samples (Objective 3—Risk Factor). Search Methods Searches were conducted between April and June 2022, capturing research until December 2021. We contacted expert networks, hand‐searched specialist journals, harvested records from published reviews, and examined references lists for included papers to identify additional studies. Selection Criteria Studies needed to empirically examine mental health difficulties and terrorism. To be included under Objective 1 (Prevalence) and Objective 2 (Temporality), studies had to adopt cross‐sectional, cohort, or case‐control design and report prevalence rates of mental health difficulties in terrorist samples, with studies under Objective 2 also needing to report prevalence of difficulties before detection or involvement in terrorism. For Objective 3 (Risk Factor) studies where there was variability in terrorist behaviour (involved vs. not involved) were included. Data Collection and Analysis Captured records were screened in DisillterSR by two authors. Risk of bias was assessed using Joanna Briggs Institute checklists, and random‐effects meta‐analysis conducted in Comprehensive Meta‐Analysis software. Results Fifty‐six papers reporting on 73 different terrorist samples (i.e., studies) (n = 13,648) were identified. All were eligible for Objective 1. Of the 73 studies, 10 were eligible for Objective 2 (Temporality) and nine were eligible for Objective 3 (Risk Factor). For Objective 1, the life‐time prevalence rate of diagnosed mental disorder in terrorist samples (k = 18) was 17.4% [95% confidence interval (CI) = 11.1%–26.3%]. When collapsing all studies reporting psychological problems, disorder, and suspected disorder into one meta‐analyses (k = 37), the pooled prevalence rate was 25.5% (95% CI = 20.2%–31.6%). When isolating studies reporting data for any mental health difficulty that emerged before either engagement in terrorism or detection for terrorist offences (Objective 2: Temporality), the life‐time prevalence rate was 27.8% (95% CI = 20.9%–35.9%). For Objective 3 (Risk Factor), it was not appropriate to calculate a pooled effect size due the differences in comparison samples. Odds ratios for these studies ranged from 0.68 (95% CI = 0.38–1.22) to 3.13 (95% CI = 1.87–5.23). All studies were assessed as having high‐risk of bias which, in part, reflects challenges conducting terrorism research. Author's Conclusions This review does not support the assertion that terrorist samples are characterised by higher rates of mental health difficulties than would be expected in the general population. Findings have implications for future research in terms of design and reporting. There are also implications for practice with regards the inclusion of mental health difficulties as indicators of risk.

Suggested Citation

  • Kiran M. Sarma & Sarah L. Carthy & Katie M. Cox, 2022. "Mental disorder, psychological problems and terrorist behaviour: A systematic review and meta‐analysis," Campbell Systematic Reviews, John Wiley & Sons, vol. 18(3), September.
    • Handle: RePEc:wly:camsys:v:18:y:2022:i:3:n:e1268
    DOI: 10.1002/cl2.1268
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    1. Nicolas Campelo & Laura Bouzar & Alice Oppetit & Hugues Pellerin & Serge Hefez & Guillaume Bronsard & David Cohen & Dounia Bouzar, 2018. "Joining the Islamic State from France between 2014 and 2016: an observational follow-up study," Palgrave Communications, Palgrave Macmillan, vol. 4(1), pages 1-10, December.
    2. Sandra Baez & Eduar Herrera & Adolfo M. García & Facundo Manes & Liane Young & Agustín Ibáñez, 2017. "Outcome-oriented moral evaluation in terrorists," Nature Human Behaviour, Nature, vol. 1(6), pages 1-9, June.
    3. Li, Minghao & Zhang, Wendong & Hart, Chad, 2018. "What Have We Learned from China’s Past Trade Retaliation Strategies?," Choices: The Magazine of Food, Farm, and Resource Issues, Agricultural and Applied Economics Association, vol. 33(2), April.
    4. Steven Windisch & Susann Wiedlitzka & Ajima Olaghere & Elizabeth Jenaway, 2022. "Online interventions for reducing hate speech and cyberhate: A systematic review," Campbell Systematic Reviews, John Wiley & Sons, vol. 18(2), June.
    5. Md Mahbub Hossain & Abida Sultana & Samia Tasnim & Qiping Fan & Ping Ma & E Lisako J McKyer & Neetu Purohit, 2020. "Prevalence of mental disorders among people who are homeless: An umbrella review," International Journal of Social Psychiatry, , vol. 66(6), pages 528-541, September.
    6. Sarah L. Carthy & Colm B. Doody & Katie Cox & Denis O'Hora & Kiran M. Sarma, 2020. "Counter‐narratives for the prevention of violent radicalisation: A systematic review of targeted interventions," Campbell Systematic Reviews, John Wiley & Sons, vol. 16(3), September.
    7. Unti Ludigdo & Ali Mashuri, 2021. "Negative Evaluations of National Ethics and Its Impact on Islamic Radicalism," SAGE Open, , vol. 11(3), pages 21582440211, August.
    8. Thomas, Jakana L. & Bond, Kanisha D., 2015. "Women's Participation in Violent Political Organizations," American Political Science Review, Cambridge University Press, vol. 109(3), pages 488-506, August.
    9. Shannon Kugley & Anne Wade & James Thomas & Quenby Mahood & Anne‐Marie Klint Jørgensen & Karianne Hammerstrøm & Nila Sathe, 2017. "Searching for studies: a guide to information retrieval for Campbell systematic reviews," Campbell Systematic Reviews, John Wiley & Sons, vol. 13(1), pages 1-73.
    10. Kiran M. Sarma & Sarah L. Carthy & Katie M. Cox, 2022. "PROTOCOL: Mental disorder, psychological problems and terrorist behaviour: A systematic review," Campbell Systematic Reviews, John Wiley & Sons, vol. 18(2), June.
    11. Kamaldeep Bhui & Brian Everitt & Edgar Jones, 2014. "Might Depression, Psychosocial Adversity, and Limited Social Assets Explain Vulnerability to and Resistance against Violent Radicalisation?," PLOS ONE, Public Library of Science, vol. 9(9), pages 1-10, September.
    12. Ashworth, Scott & Clinton, Joshua D. & Meirowitz, Adam & Ramsay, Kristopher W., 2008. "Design, Inference, and the Strategic Logic of Suicide Terrorism," American Political Science Review, Cambridge University Press, vol. 102(2), pages 269-273, May.
    13. Michael J. Soules, 2022. "The tradeoffs of using female suicide bombers," Conflict Management and Peace Science, Peace Science Society (International), vol. 39(1), pages 3-23, January.
    14. Rink, Anselm & Sharma, Kunaal, 2018. "The Determinants of Religious Radicalization: Evidence from Kenya," EconStor Open Access Articles and Book Chapters, ZBW - Leibniz Information Centre for Economics, vol. 62(6), pages 1229-1261.
    15. Sandra Baez & Eduar Herrera & Adolfo M. García & Facundo Manes & Liane Young & Agustín Ibáñez, 2017. "Correction: Corrigendum: Outcome-oriented moral evaluation in terrorists," Nature Human Behaviour, Nature, vol. 1(1), pages 1-1, August.
    16. Howard White & Hugh Waddington, 2012. "Why do we care about evidence synthesis? An introduction to the special issue on systematic reviews," Journal of Development Effectiveness, Taylor & Francis Journals, vol. 4(3), pages 351-358, September.
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