Systematic review: Risk factors and mechanisms of radicalization in lone-actor grievance-fueled violence

References

(studies marked with * included in systematic review)

• *Allely, C. S., Wilson, P., Minnis, H., Thompson, L., Yaksic, E., & Gillberg, C. (2017). Violence is rare in autism: When it does occur, is it sometimes extreme? The Journal of Psychology, 151(1), 49–68. https://doi.org/10.1080/00223980.2016.1175998
   PubMed Web of Science ®Google Scholar
• *Allwinn, M., Hoffmann, J., & Meloy, J. R. (2019). German mass murderers and their proximal warning behaviors. Journal of Threat Assessment and Management, 6(1), 1–22. https://doi.org/10.1037/tam0000122
   Google Scholar
• *Altay, A., Baykal-Gürsoy, M., & Hemmer, P. (2020). Behavior associations in lone-actor terrorists. Terrorism and Political Violence, 1–29. https://doi.org/10.1080/09546553.2020.1787384
   Google Scholar
• *Anisin, A. (2018). A configurational analysis of 44 US mass shootings: 1975–2015. International Journal of Comparative and Applied Criminal Justice, 42(1), 55–73. https://doi.org/10.1080/01924036.2016.1233444
   Web of Science ®Google Scholar
• Antonovsky, A. (2012). Unraveling the mystery of health: How people manage stress and stay well. Jossey-Bass Publishers. https://doi.org/10.4135/9781446221129.n9
   Google Scholar
• *Baele, S. J. (2017). Lone-actor terrorists’ emotions and cognition: An evaluation beyond stereotypes. Political Psychology, 38(3), 449–468. https://doi.org/10.1111/pops.12365
   Web of Science ®Google Scholar
• *Baele, S. J., Brace, L., & Coan, T. G. (2019). From “Incel” to “Saint”: Analyzing the violent worldview behind the 2018 Toronto attack. Terrorism and Political Violence, 33(8), 1667–1691. https://doi.org/10.1080/09546553.2019.1638256
   Web of Science ®Google Scholar
• Bandura, A. (1999). Moral disengagement in the perpetration of inhumanities. In Recent developments in criminological theory: Toward disciplinary diversity and theoretical integration (vol. 3, pp. 135–151). Routledge. https://doi.org/10.4324/9781315799292-3
   Google Scholar
• Bandura, A., Barbaranelli, C., Caprara, G. V., & Pastorelli, C. (1996). Mechanisms of moral disengagement in the exercise of moral agency. Journal of Personality and Social Psychology, 71(2), 364–374. https://doi.org/10.1037/0022-3514.71.2.364
   Web of Science ®Google Scholar
• Barry-Walsh, J., James, D. V., & Mullen, P. E. (2020). Fixated Threat Assessment Centers: preventing harm and facilitating care in public figure threat cases and those thought to be at risk of line-actor grievance-fueled violence. CNS Spectrums, 25(5), 630–637. https://doi.org/10.1017/S1092852920000152
   PubMed Web of Science ®Google Scholar
• Beach, D., & Kaas, J. (2020). The great divides: Incommensurability, the impossibility of mixed-methodology, and what to do about it. International Studies Review, 22(2), 214–235. https://doi.org/10.1093/isr/viaa016
   Web of Science ®Google Scholar
• Berger, P., & Luckmann, T. (1967). The social construction of reality. Anchor Books.
   Google Scholar
• *Bright, D., Whelan, C., & Harris-Hogan, S. (2020). Exploring the hidden social networks of ‘lone actor’ terrorists. Crime, Law and Social Change, 74(5), 491–508. https://doi.org/10.1007/s10611-020-09905-2
   Web of Science ®Google Scholar
• *Böckler, N., Hoffmann, J., & Zick, A. (2015). The Frankfurt airport attack: A case study on the radicalization of a lone-actor terrorist. Journal of Threat Assessment and Management, 2(3–4), 153–163. https://doi.org/10.1037/tam0000045
   Google Scholar
• *Böckler, N., Leuschner, V., Zick, A., & Scheithauer, H. (2018). Same but different? Developmental pathways to demonstrative targeted attacks - qualitative case analyses of adolescent and young adult perpetrators of targeted school attacks and Jihadi terrorist attacks in Germany. International Journal of Developmental Science, 12(1–2), 5–24. https://doi.org/10.3233/DEV-180255
   PubMedGoogle Scholar
• *Bondu, R., & Scheithauer, H. (2015). Narcissistic symptoms in German school shooters. International Journal of Offender Therapy and Comparative Criminology, 59(14), 1520–1535. https://doi.org/10.1177/0306624X14544155
   PubMed Web of Science ®Google Scholar
• Borum, R. (2011). Radicalization into violent extremism I: A review of social science theories. Journal of Strategic Security, 4(4), 7–36. https://doi.org/10.5038/1944-0472.4.4.1
   Google Scholar
• Borum, R. (2014). Psychological vulnerabilities and propensities for involvement in violent extremism. Behavioral Sciences & the Law, 32(3), 286–305. https://doi.org/10.1002/bsl.2110
   PubMed Web of Science ®Google Scholar
• Borum, R., Fein, R., & Vossekuil, B. (2012). A dimensional approach to analyzing lone offender terrorism. Aggression and Violent Behavior, 17(5), 389–396. https://doi.org/10.1016/j.avb.2012.04.003
   Web of Science ®Google Scholar
• *Bouhana, N., Corner, E., Gill, P., & Schuurman, B. (2018). Background and preparatory behaviours of right-wing extremist lone actors: A comparative study. Perspectives on Terrorism, 12(6), 150–163. https://www.scopus.com/inward/record.uri?eid=2-s2.0-85065333043&partnerID=40&md5=2d584663d93090e94fa10207e970a8f1NS-
   Google Scholar
• *Capellan, J. A. (2015). Lone wolf terrorist or deranged shooter? A study of ideological active shooter events in the United States, 1970–2014. Studies in Conflict & Terrorism, 38(6), 395–413. https://doi.org/10.1080/1057610X.2015.1008341
   Web of Science ®Google Scholar
• *Capellan, J. A., & Anisin, A. (2018). A distinction without a difference? Examining the causal pathways behind ideologically motivated mass public shootings. Homicide Studies, 22(3), 235–255. https://doi.org/10.1177/1088767918770704
   Web of Science ®Google Scholar
• *Capellan, J. A., Johnson, J., Porter, J. R., & Martin, C. (2019). Disaggregating mass public shootings: A comparative analysis of disgruntled employee, school, ideologically motivated, and rampage shooters. Journal of Forensic Sciences, 64(3), 814–823. https://doi.org/10.1111/1556-4029.13985
   PubMed Web of Science ®Google Scholar
• Charmaz, K. (2006). Construction grounded theory: A practical guide through qualitative analysis. SAGE Publications.
   Google Scholar
• Clark, L. A., Cuthbert, B., Lewis-Fernández, R., Narrow, W. E., & Reed, G. M. (2017). Three approaches to understanding and classifying mental disorder: ICD-11, DSM-5, and the National Institute of Mental Health's Research Domain Criteria (RDoC). Psychological Science in the Public Interest: A Journal of the American Psychological Society, 18(2), 72–145. https://doi.org/10.1177/1529100617727266
   PubMed Web of Science ®Google Scholar
• *Clemmow, C., Bouhana, N., & Gill, P. (2020). Analyzing person-exposure patterns in lone-actor terrorism: Implications for threat assessment and intelligence gathering. Criminology & Public Policy, 19(2), 451–482. https://doi.org/10.1111/1745-9133.12466
   Web of Science ®Google Scholar
• *Clemmow, C., Gill, P., Bouhana, N., Silver, J., & Horgan, J. (2020). Disaggregating lone-actor grievance-fuelled violence: comparing lone-actor terrorists and mass murderers. Terrorism and Political Violence, 1–26. https://doi.org/10.1080/09546553.2020.1718661
   Google Scholar
• Clemmow, C., Schumann, S., Salman, N. L., & Gill, P. (2020). The base rate study: Developing base rates for risk factors and indicators for engagement in violent extremism. Journal of Forensic Sciences, 65(3), 865–881. https://doi.org/10.1111/1556-4029.14282
   PubMed Web of Science ®Google Scholar
• *Corner, E., & Gill, P. (2015). A false dichotomy? Mental illness and lone-actor terrorism. Law and Human Behavior, 39(1), 23–34. https://doi.org/10.1037/lhb0000102
   PubMed Web of Science ®Google Scholar
• *Corner, E., Bouhana, N., & Gill, P. (2019). The multifinality of vulnerability indicators in lone-actor terrorism. Psychol. Crime Law, 25(2), 111–132. https://doi.org/10.1080/1068316X.2018.1503664
   Web of Science ®Google Scholar
• *Dagenhard, P., Thompson, A., Dake, J., Pescara-Kovach, L., & Rega, P. (2019). Active shooter events in schools: A review of reports and related materials. Health Behavior and Policy Review, 6(3), 219–231. https://doi.org/10.14485/HBPR.6.3.2
   Web of Science ®Google Scholar
• De Venanzi, A. (2012). School shootings in the USA: Popular cultures as risk, teen marginality, and violence against peers. Crime, Media, Culture: An International Journal, 8(3), 261–278. https://doi.org/10.1177/1741659012443233
   Web of Science ®Google Scholar
• Doosje, B., Moghaddam, F. M., Kruglanski, A. W., Wolf, A. D., Mann, L., Feddes, A. R., De Wolf, A., Mann, L., & Feddes, A. R. (2016). Terrorism, radicalization and de-radicalization. Current Opinion in Psychology, 11, 79–84. https://doi.org/10.1016/j.copsyc.2016.06.008
   Web of Science ®Google Scholar
• *Dumitriu, C. (2013). School violence around the world: A social phenomenon. Procedia - Social and Behavioral Sciences, 92, 299–308. https://doi.org/10.1016/j.sbspro.2013.08.676
   Google Scholar
• *Duwe, G. (2020). Patterns and prevalence of lethal mass violence. Criminology & Public Policy, 19(1), 17–35. https://doi.org/10.1111/1745-9133.12478
   Web of Science ®Google Scholar
• *Erlandsson, Å., & Reid Meloy, J. (2018). The Swedish school attack in Trollhättan. Journal of Forensic Sciences, 63(6), 1917–1927. https://doi.org/10.1111/1556-4029.13800
   PubMed Web of Science ®Google Scholar
• *Farr, K. (2018). Adolescent rampage school shootings: Responses to failing masculinity performances by already-troubled boys. Gender Issues, 35(2), 73–97. https://doi.org/10.1007/s12147-017-9203-z
   Web of Science ®Google Scholar
• *Farr, K. (2019). Trouble with the other: The role of romantic rejection in rampage school shootings by adolescent males. Violence and Gender, 6(3), 147–153. https://doi.org/10.1089/vio.2018.0046
   Web of Science ®Google Scholar
• *Fast, J. (2013). Unforgiven and alone: Brenda spencer and secret shame. In N. Böckler, W. Heitmeyer, T. Seeger, & P. Sitzer (Eds.), School shootings: International research, case studies, and concepts for prevention (pp. 245–261). Springer-Verlag. https://doi.org/10.1007/978-1-4614-5526-4_11
   Google Scholar
• *FBI. (2019). Lone offender – A study of lone offender terrorism in the United States (1972-2015). National Center for the Analysis of Violent Crime. https://www.fbi.gov/news/stories/fbi-releases-lone-offender-terrorism-report-111319
   Google Scholar
• *Fridel, E. E. (2017). A multivariate comparison of family, felony, and public mass murders in the United States. Journal of Interpersonal Violence, 36(3–4), 1092–1027. https://doi.org/10.1177/0886260517739286
   PubMedGoogle Scholar
• *Gerard, F. J., Whitfield, K. C., Porter, L. E., & Browne, K. D. (2016). Offender and offence characteristics of school shooting incidents. Journal of Investigative Psychology and Offender Profiling, 13(1), 22–38. https://doi.org/10.1002/jip.1439
   Web of Science ®Google Scholar
• *Gill, P., Corner, E., McKee, A., Hitchen, P., & Betley, P. (2019). What do closed source data tell us about lone actor terrorist behavior? A research note. Terrorism and Political Violence, 34(1), 113–130. https://doi.org/10.1080/09546553.2019.1668781
   Web of Science ®Google Scholar
• *Gill, P., Horgan, J., & Deckert, P. (2014). Bombing alone: Tracing the motivations and antecedent behaviors of lone-actor terrorists. Journal of Forensic Sciences, 59(2), 425–435. https://doi.org/10.1111/1556-4029.12312
   PubMed Web of Science ®Google Scholar
• *Gill, P., Silver, J., Horgan, J., & Corner, E. (2017). Shooting alone: The pre-attack experiences and behaviors of U.S. solo mass murderers. Journal of Forensic Sciences, 62(3), 710–714. https://doi.org/10.1111/1556-4029.13330
   PubMed Web of Science ®Google Scholar
• Gøtzsche-Astrup, O. (2018). The time for causal designs: Review and evaluation of empirical support for mechanisms of political radicalisation. Aggression and Violent Behavior, 39, 90–99. https://doi.org/10.1016/j.avb.2018.02.003
   Web of Science ®Google Scholar
• Gøtzsche-Astrup, O., & Lindekilde, L. (2019). Either or? Reconciling findings on mental health and extremism using a dimensional rather than categorical paradigm. Journal of Forensic Sciences, 64(4), 982–988. https://doi.org/10.1111/1556-4029.14014
   PubMed Web of Science ®Google Scholar
• *Gruenewald, J., Chermak, S., & Freilich, J. D. (2013a). Distinguishing “loner” attacks from other domestic extremist violence: A comparison of far-right homicide incident and offender characteristics. Criminology & Public Policy, 12(1), 65–91. https://doi.org/10.1111/1745-9133.12008
   Web of Science ®Google Scholar
• *Gruenewald, J., Chermak, S., & Freilich, J. D. (2013b). Far-right lone wolf homicides in the United States. Studies in Conflict & Terrorism, 36(12), 1005–1024. https://doi.org/10.1080/1057610X.2013.842123
   Web of Science ®Google Scholar
• Hamm, M. S., & Spaaij, R. (2017). The Age of Lone Wolf Terrorism. Columbia University Press.
   Google Scholar
• *Harrison, M. A., & Bowers, T. G. (2010). Autogenic massacre as a maladaptive response to status threat. Journal of Forensic Psychiatry & Psychology, 21(6), 916–932. https://doi.org/10.1080/14789949.2010.506618
   Web of Science ®Google Scholar
• *Hempel, A. G., Levine, R. E., Meloy, J. R., & Westermeyer, J. (2000). A cross-cultural review of sudden mass assault by a single individual in the oriental and occidental cultures. Journal of Forensic Sciences, 45(3), 582–588. https://doi.org/10.1520/JFS14732J
   PubMed Web of Science ®Google Scholar
• Hoffman, B., Ware, J., & Shapiro, E. (2020). Assessing the threat of incel violence. Studies in Conflict & Terrorism, 43(7), 565–587. https://doi.org/10.1080/1057610X.2020.1751459
   Web of Science ®Google Scholar
• *Hofmann, D. C. (2020). How “Alone” are Lone-Actors? Exploring the Ideological, Signaling, and Support Networks of Lone-Actor Terrorists. Studies in Conflict & Terrorism, 43(7), 657–678. https://doi.org/10.1080/1057610X.2018.1493833
   Web of Science ®Google Scholar
• Hogg, M. A., & Adelman, J. (2013). Uncertainty-identity theory: Extreme groups, radical behavior, and authoritarian leadership. Journal of Social Issues, 69(3), 436–454. https://doi.org/10.1111/josi.12023
   Web of Science ®Google Scholar
• *Holt, T. J., Freilich, J. D., Chermak, S. M., Mills, C., & Silva, J. (2019). Loners, colleagues, or peers? Assessing the social organization of radicalization. American Journal of Criminal Justice, 44(1), 83–105. https://doi.org/10.1007/s12103-018-9439-5
   Web of Science ®Google Scholar
• Horgan, J. (2008). From profiles to pathways and roots to routes: Perspectives from psychology on radicalization into terrorism. The ANNALS of the American Academy of Political and Social Science, 618(1), 80–94. https://doi.org/10.1177/0002716208317539
   Web of Science ®Google Scholar
• Hurrelmann, K. (1988). Social structure and personality development. Cambridge.
   Google Scholar
• *Ioannou, M., Hammond, L., & Simpson, O. (2015). A model for differentiating school shooters characteristics. Journal of Criminal Psychology, 5(3), 188–200. https://doi.org/10.1108/JCP-06-2015-0018
   Web of Science ®Google Scholar
• *Jah, M. K., & Khoshnood, A. (2019). Profiling lone-actor terrorists: A cross-sectional study of lone-actor terrorists in Western Europe (2015–2016). Journal of Strategic Security, 12(4), 25–49. https://doi.org/10.5038/1944-0472.12.4.1736
   Google Scholar
• *Katon, A., Brugh, C. S., Desmarais, S. L., Simons-Rudolph, J., & Zottola, S. A. (2021). A qualitative analysis of drivers among military-affiliated and civilian lone actor terrorists inspired by Jihadism. Studies in Conflict & Terrorism, 44(2), 138–155. https://doi.org/10.1080/1057610X.2020.1799520
   Web of Science ®Google Scholar
• Kenyon, J., Baker-beall, C., & Binder, J. (2021). Studies in conflict & terrorism lone-actor terrorism – A systematic literature review lone-actor terrorism – A systematic literature review. Studies in Conflict & Terrorism, 1–24. https://doi.org/10.1080/1057610X.2021.1892635
   Google Scholar
• *Klein, J. (2006). Sexuality and school shootings: What role does teasing play in school massacres? Journal of Homosexuality, 51(4), 39–62. https://doi.org/10.1300/J082v51n04_03
   PubMed Web of Science ®Google Scholar
• *Knoll, J. L. (2010). The “pseudocommando” mass murderer: Part II, The language of revenge. Journal of the American Academy of Psychiatry and the Law, 38(2), 263–272. https://www.scopus.com/inward/record.uri?eid=2-s2.0-77955870501&partnerID=40&md5=be13c4d5d6e4964c8f1e3d855663ad9fNS-
   PubMed Web of Science ®Google Scholar
• Koomen, W., & Van Der Pligt, J. (2016). The psychology of radicalization and terrorism. Routledge. https://doi.org/10.1080/13537903.2016.1256667
   Google Scholar
• Kruglanski, A. W., & Bertelsen, P. (2020). Life psychology and significance quest: a complementary approach to violent extremism and counter-radicalisation approach to violent extremism and counter-radicalisation. Journal of Policing, Intelligence and Counter Terrorism, 15(1), 1–22. https://doi.org/10.1080/18335330.2020.1725098
   Google Scholar
• Labov, W., & Waletzky, J. (1967). Narrative analysis: Oral versions of personal experience. In J. Helms (Ed.), Essays on the verbal and visual arts (pp. 12–44). University of Washington Press.
   Google Scholar
• *Langman, P. (2009). Rampage school shooters: A typology. Aggression and Violent Behavior, 14(1), 79–86. https://doi.org/10.1016/j.avb.2008.10.003
   Web of Science ®Google Scholar
• *Langman, P. (2013). Thirty-five rampage school shooters: Trends, patterns, and typology. In N. Böckler, W. Heitmeyer, T. Seeger, & P. Sitzer (Eds.), School shootings: International research, case studies, and concepts for prevention (pp. 131–156). Springer-Verlag. https://doi.org/10.1007/978-1-4614-5526-4_6
   Google Scholar
• *Lankford, A. (2013). A comparative analysis of suicide terrorists and rampage, workplace, and school shooters in the United States From 1990 to 2010. Homicide Studies, 17(3), 255–274. https://doi.org/10.1177/1088767912462033
   Web of Science ®Google Scholar
• Larsen, R., Buss, D., Wismeijer, A., & Song, J. (2017). (contrib). Personality psychology: Domains of knowledge about human nature. McGraw-Hill Education.
   Google Scholar
• *Leary, M. R., Kowalski, R. M., Smith, L., & Phillips, S. (2003). Teasing, rejection, and violence: Case studies of the school shootings. Aggressive Behavior, 29(3), 202–214. https://doi.org/10.1002/ab.10061
   Web of Science ®Google Scholar
• *Lenhardt, A. M. C., Farrell, M. L., & Graham, L. W. (2010). Providing anchors-reclaiming our troubled youth: Lessons for leaders from a study of 15 targeted school shooters. The Educational Forum, 74(2), 104–116. https://doi.org/10.1080/00131721003604405
   Google Scholar
• *Lenhardt, A. M. C., Graham, L. W., & Farrell, M. L. (2018). A framework for school safety and risk management: Results from a study of 18 targeted school shooters. The Educational Forum, 82(1), 3–20. https://doi.org/10.1080/00131725.2018.1381792
   Web of Science ®Google Scholar
• *Liem, M., van Buuren, J., de Roy van Zuijdewijn, J., Schönberger, H., & Bakker, E. (2018). European lone actor terrorists versus “common” homicide offenders: An empirical analysis. Homicide Studies, 22(1), 45–69. https://doi.org/10.1177/1088767917736797
   PubMed Web of Science ®Google Scholar
• *Lindekilde, L., Malthaner, S., & O’Connor, F. (2019). Peripheral and embedded: relational patterns of lone-actor terrorist radicalization. Dynamics of Asymmetric Conflict, 12(1), 20–41. https://doi.org/10.1080/17467586.2018.1551557
   Google Scholar
• *Lindquist, O., & Lidberg, L. (1998). Violent mass shootings in Sweden from 1960 to 1995: profiles, patterns, and motives. The American Journal of Forensic Medicine and Pathology, 19(1), 34–45. https://doi.org/10.1097/00000433-199803000-00006
   PubMed Web of Science ®Google Scholar
• *Malkki, L. (2014). Political elements in post-columbine school shootings in Europe and North America. Terrorism and Political Violence, 26(1), 185–210. https://doi.org/10.1080/09546553.2014.849933
   Web of Science ®Google Scholar
• Malthaner, S. (2017). Radicalization: The evolution of an analytical paradigm. European Journal of Sociology, 58(3), 369–401. https://doi.org/10.1017/S0003975617000182
   Web of Science ®Google Scholar
• McCauley, C., & Moskalenko, S. (2017). Friction - How conflict radicalizes them and us. Oxford University Press.
   Google Scholar
• *McCauley, C., Moskalenko, S., & Son, B. V. (2013). Characteristics of lone-wolf violent offenders: a comparison of assassins and school attackers. Perspective on Terrorism, 7(1), 4–24. http://www.terrorismanalysts.com/pt/index.php/pot/article/view/240/pdf
   Google Scholar
• *Meloy, J. R., Hempel, A. G., Gray, B. T., Mohandie, K., Shiva, A., & Richards, T. C. (2004). A comparative analysis of North American adolescent and adult mass murderers. Behavioral Sciences & the Law, 22(3), 291–309. https://doi.org/10.1002/bsl.586
   PubMed Web of Science ®Google Scholar
• *Meloy, J. R., Hempel, A. G., Mohandie, K., Shiva, A. A., & Gray, B. T. (2001). Offender and offense characteristics of a nonrandom sample of adolescent mass murderers. Journal of the American Academy of Child & Adolescent Psychiatry, 40(6), 719–728. https://doi.org/10.1097/00004583-200106000-00018
   PubMed Web of Science ®Google Scholar
• *Meloy, J. R., & Gill, P. (2016). The lone-actor terrorist and the TRAP-18. Journal of Threat Assessment and Management, 3(1), 37–52. https://doi.org/10.1037/tam0000061
   Google Scholar
• *Meloy, J. R., Goodwill, A. M., Meloy, M. J., Amat, G., Martinez, M., & Morgan, M. (2019). Some TRAP-18 indicators discriminate between terrorist attackers and other subjects of national security concern. Journal of Threat Assessment and Management, 6(2), 93–110. https://doi.org/10.1037/tam0000119
   Google Scholar
• *Merari, A., & Ganor, B. (2020). Interviews with, and tests of, Palestinian independent assailants. Terrorism and Political Violence, 1–22. https://doi.org/10.1080/09546553.2020.1821668
   Google Scholar
• *Misiak, B., Samochowiec, J., Bhui, K., Schouler-Ocak, M., Demunter, H., Kuey, L., Raballo, A., Gorwood, P., Frydecka, D., & Dom, G. (2019). A systematic review on the relationship between mental health, radicalization and mass violence. European Psychiatry: The Journal of the Association of European Psychiatrists, 56, 51–59. https://doi.org/10.1016/j.eurpsy.2018.11.005
   PubMed Web of Science ®Google Scholar
• Moher, D., Liberati, A., Tetzlaff, J., & Altman, D. G, for the PRISMA Group. (2009). Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. BMJ, 339(jul21 1), b2535–b2535. https://doi.org/10.1136/bmj.b2535
   PubMed Web of Science ®Google Scholar
• *Myketiak, C. (2016). Fragile masculinity: social inequalities in the narrative frame and discursive construction of a mass shooter’s autobiography/manifesto. Contemporary Social Science, 11(4), 289–303. https://doi.org/10.1080/21582041.2016.1213414
   Web of Science ®Google Scholar
• *Neuman, Y., Assaf, D., Cohen, Y., & Knoll, J. L. (2015). Profiling school shooters: Automatic text-based analysis. Frontiers in Psychiatry, 6(86), 86–85. https://doi.org/10.3389/fpsyt.2015.00086
   PubMedGoogle Scholar
• *Oksanen, A., Nurmi, J., Vuori, M., & Räsänen, P. (2013). Jokela: The social roots of a school shooting tragedy in Finland. In N. Böckler, W. Heitmeyer, T. Seeger, & P. Sitzer (Eds.), School shootings: International research, case studies, and concepts for prevention (pp. 189–215). Springer-Verlag. https://doi.org/10.1007/978-1-4614-5526-4_9
   Google Scholar
• *Oliffe, J. L., Han, C. S. E., Drummond, M., Sta. Maria, E., Bottorff, J. L., & Creighton, G. (2015). Men, masculinities, and murder-suicide. American Journal of Men's Health, 9(6), 473–485. https://doi.org/10.1177/1557988314551359
   PubMed Web of Science ®Google Scholar
• Olweus, D. (1994). Annotation: Bullying at school: Basic facts and effects of a school based intervention program. Journal of Child Psychology and Psychiatry, 35, 1171–1190. https://doi.org/10.1111/j.1469-7610.1994.tbo1229.x
   Google Scholar
• Ozer, S., & Bertelsen, P. (2018). Capturing violent radicalization: Developing and validating scales measuring central aspects of radicalization. Scandinavian Journal of Psychology, 59(6), 653–660. https://doi.org/10.1111/sjop.12484
   PubMed Web of Science ®Google Scholar
• Paulhus, D. L. (2014). Toward a taxonomy of dark personalities. Current Directions in Psychological Science, 23(6), 421–426. https://doi.org/10.1177/0963721414547737
   Web of Science ®Google Scholar
• *Peter, E., Seidenbecher, S., Bogerts, B., Dobrowolny, H., & Schöne, M. (2019). Mass murders in Germany–classification of surviving offenders based on the examination of court files. The Journal of Forensic Psychiatry & Psychology, 30(3), 381–400. https://doi.org/10.1080/14789949.2019.1593486
   Web of Science ®Google Scholar
• *Pfeifer, B., & Ganzevoort, R. (2017). Tell me why? Existential concerns of school shooters. Religious Education, 112(2), 123–135. https://doi.org/10.1080/00344087.2016.1113908
   Web of Science ®Google Scholar
• Plummer, K. (1995). Telling sexual stories: power, change and social world. Routledge.
   Google Scholar
• *Presser, L. (2012). Getting on top through mass murder: Narrative, metaphor, and violence. Crime, Media, Culture: An International Journal, 8(1), 3–21. https://doi.org/10.1177/1741659011430443
   Web of Science ®Google Scholar
• *Rees, C. A., Lee, L. K., Fleegler, E. W., & Mannix, R. (2019). Mass school shootings in the United States: A novel root cause analysis using lay press reports. Clinical Pediatrics, 58(13), 1423–1428. https://doi.org/10.1177/0009922819873650
   PubMed Web of Science ®Google Scholar
• Ryff, C. D. (1989). Happiness is everything, or is it? Explorations on the meaning of psychological well-being. Journal of Personality and Social Psychology, 57(6), 1069–1081. https://doi.org/10.1037/0022-3514.57.6.1069
   Web of Science ®Google Scholar
• Ryff, C. D., & Keyes, L. M. (1995). The structure of psychological well-being revisited. Journal of Personality and Social Psychology, 69(4), 719–727. https://doi.org/10.1002/1520-6696(197801)14:1<57::AID-JHBS2300140109>3.0.CO;2-7
   PubMed Web of Science ®Google Scholar
• Schmid, A. (2013). Radicalisation, de-radicalisation, counter-radicalisation: A conceptual discussion and literature review. The International Centre for Counter-Terrorism – The Hague, 4, 1–97. https://doi.org/10.19165/2013.1.02
   Google Scholar
• *Schuurman, B., Bakker, E., Gill, P., & Bouhana, N. (2018). Lone actor terrorist attack planning and preparation: A data-driven analysis. Journal of Forensic Sciences, 63(4), 1191–1200. https://doi.org/10.1111/1556-4029.13676
   PubMed Web of Science ®Google Scholar
• Siddaway, A. P., Wood, A. M., & Hedges, L. V. (2019). How to do a systematic review: A best practice guide for conducting and reporting narrative reviews, meta-analyses, and meta-syntheses. Annual Review of Psychology, 70, 747–770. https://doi.org/10.1146/annurev-psych-010418-102803
   PubMed Web of Science ®Google Scholar
• Silke, A. (1998). Cheshire-cat logic: The recurring theme of terrorist abnormality in psychological research. Psychology, Crime and Law, 4(1), 51–69. https://doi.org/10.1080/10683169808401747
   Web of Science ®Google Scholar
• *Silva, J. R., & Greene-Colozzi, E. A. (2019). Fame-seeking mass shooters in America: Severity, characteristics, and media coverage. Aggression and Violent Behavior, 48, 24–35. https://doi.org/10.1016/j.avb.2019.07.005
   Web of Science ®Google Scholar
• *Silver, J., Horgan, J., & Gill, P. (2019). Shared struggles? Cumulative strain theory and public mass murderers from 1990 to 2014. Homicide Studies, 23(1), 64–84. https://doi.org/10.1177/1088767918802881
   Web of Science ®Google Scholar
• Solomon, S., Greenberg, J., & Pyszczynski, T. (2004). The cultural animal: Twenty years of terror management theory and research. In J. Greenberg, S. L. Koole, & T. A. Pyszczynski (red.), Handbook of experimental existential psychology (pp. 13–34). Guilford Press.
   Google Scholar
• *Sommer, F., Leuschner, V., Fiedler, N., Madfis, E., & Scheithauer, H. (2020). The role of shame in developmental trajectories towards severe targeted school violence: An in-depth multiple case study. Aggression and Violent Behavior, 51, 101386. https://doi.org/10.1016/j.avb.2020.101386
   Web of Science ®Google Scholar
• *Sommer, F., Leuschner, V., & Scheithauer, H. (2014). Bullying, romantic rejection, and conflicts with teachers: The crucial role of social dynamics in the development of school shootings - a systematic review. International Journal of Developmental Science, 8(1–2), 3–24. https://doi.org/10.3233/DEV-140129
   Google Scholar
• *Spaaij, R. (2010). The enigma of lone wolf terrorism: An assessment. Studies in Conflict & Terrorism, 33(9), 854–870. https://doi.org/10.1080/1057610X.2010.501426
   Web of Science ®Google Scholar
• *Taylor, M. A. (2018). A comprehensive study of mass murder precipitants and motivations of offenders. International Journal of Offender Therapy and Comparative Criminology, 62(2), 427–449. https://doi.org/10.1177/0306624X16646805
   PubMed Web of Science ®Google Scholar
• *Timm, J. D., & Aydin, N. (2020). Culturally independent risk factors of school and campus rampages: An analysis of international case studies of educational institution violence. Aggression and Violent Behavior, 55, 101514. https://doi.org/10.1016/j.avb.2020.101514
   Web of Science ®Google Scholar
• Victoroff, J. (2005). The mind of the terrorist : A review and critique of psychological approaches. Journal of Conflict Resolution, 49(1), 3–42. https://doi.org/10.1177/0022002704272040
   Web of Science ®Google Scholar
• Webber, D., & Kruglanski, A. W. (2018). The social psychological makings of a terrorist. Current Opinion in Psychology, 19, 131–134. https://doi.org/10.1016/j.copsyc.2017.03.024
   PubMed Web of Science ®Google Scholar
• Webster, D. M., & Kruglanski, A. W. (1994). Individual differences in need for cognitive closure. Journal of Personality and Social Psychology, 67(6), 1049–1062. https://doi.org/10.1037/0022-3514.67.6.1049
   PubMed Web of Science ®Google Scholar
• *White, S. G. (2017). Case study: The Isla Vista campus community mass murder. Journal of Threat Assessment and Management, 4(1), 20–47. https://doi.org/10.1037/tam0000078
   Google Scholar
• Williams, K. D. (2007). Ostracism. Annual Review of Psychology, 58, 425–452. https://doi.org/10.1146/annurev.psych.58.110405.085641
   PubMed Web of Science ®Google Scholar
• *Wills, A., & Lankford, A. (2019). Indicators of unhealthy fame-seeking and attention-seeking among public mass shooters and active shooters. The Journal of Campus Behavioral Intervention (J-BIT), 7, 34–45.
   Google Scholar
• *Winter, D. A., & Tschudi, F. (2015). Construing a “perfect knight”: A personal construct investigation of mass murder. Journal of Constructivist Psychology, 28(2), 139–151. https://doi.org/10.1080/10720537.2013.846837
   Web of Science ®Google Scholar