Systematic Review on the Outcomes of Primary and Secondary Prevention Programs in the Field of Violent Radicalization


  • Sébastien Brouillette-Alarie Université du Québec à Montréal
  • Ghayda Hassan Université du Québec à Montréal
  • Wynnpaul Varela Université du Québec à Montréal
  • Sarah Ousman Université du Québec à Montréal
  • Deniz Kilinc Université du Québec à Montréal
  • Éléa Laetitia Savard Université du Québec à Montréal
  • Pablo Madriaza Université du Québec à Montréal
  • Shandon Harris-Hogan Victoria University
  • John McCoy University of Alberta
  • Cécile Rousseau McGill University
  • Michael King Organization for the Prevention of Violence
  • Vivek Venkatesh Concordia University
  • Eugene Borokhovski Concordia University
  • David Pickup Concordia University


Radicalization, Extremism, Violent, Systematic Review, Prevention Programs, Primary, Secondary, Guidelines


Since 2001, attacks attributed to extremist movements or “lone actors” have intensified and spread around the world, prompting governments to invest significant sums of money into preventing violent radicalization. Nonetheless, knowledge regarding best practices for prevention remains disparate, and the effectiveness of current practices is not clearly established. Consequently, we conducted a systematic review on the outcomes of primary and secondary prevention programs in the field of violent radicalization. Of the 11,836 documents generated, 33 studies published between 2009 and 2019 were eligible for inclusion as they comprised an empirical (quantitative or qualitative) evaluation of a prevention initiative using primary data. The majority of these studies evaluated programs targeting violent Islamist or “general” radicalization. Negative or iatrogenic effects mostly stemmed from programs aimed at specific ethnic or religious groups or focusing on surveillance and monitoring. Positive effects were noted in programs aimed at improving potential protective factors against violent radicalization. However, the reviewed studies had numerous limitations (i.e., weak experimental designs, small/biased samples, unclear definitions, incomplete methodological sections, and conflicts of interests) that hinder one’s confidence in their conclusions. Also, many studies lacked a logic model, failed to differentiate between intermediate and final outcomes, and often did not assess for negative outcomes. Encouragingly, however, some of the most methodologically sound studies contained results attesting to the effectiveness of improving protective factors against violent radicalization.


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