Contextualizing involvement in terrorist violence by considering non-significant findings: Using null results and temporal perspectives to better understand radicalization outcomes.

Irrespective of discipline, the publication of null or non-significant findings is rare in the social sciences. For burgeoning fields like terrorism research, this is particularly problematic. As well as increasing the likelihood of Type II errors, the selective reporting of significant findings ultimately impedes progression, hindering comprehensive syntheses of evidence and enabling ill-supported lines of scientific enquiry to persist. This manuscript discusses several structural and individual-level variables which failed to produce significant, linear associations with involvement in terrorist violence in a dataset (N = 206) of right-wing and jihadist extremists active in Europe and North America. After considering methodological factors such as non-random distributions of missing data, we illustrate how certain variables are significantly associated with involvement in terrorist violence at particular periods in a radicalizing individual's lifespan, but not others (i.e., pre- or post-radicalization onset). Moreover, we demonstrate that while some static, binary constructs (such as whether or not a radicalizing individual was exposed to diverse viewpoints) are not associated with terrorist violence, their influence over time produces different associations. We conclude that radicalization may be less about individuals having pre-disposing risk factors, such as biographical stressors, and more about cognitive changes that allow individuals to re-evaluate their lives through the lens of an extremist ideology. We also underline the importance of taking a temporal, rather than static, perspective to better understand the variables associated with the outcomes of radicalization trajectories.

PROTOCOL: Mental disorder, psychological problems and terrorist behaviour: A systematic review.

This is the protocol for a Campbell systematic review. The objectives are as follows: the first objective of the review (Objective 1-Prevalence) is to present a synthesis of the reported prevalence rates of mental health difficulties in terrorist samples. Where sufficient data is available, the synthesis will be sensitive to the heterogeneity of the terrorism phenomenon by exploring the rates of mental health difficulties for different forms of terrorism and for different terrorist roles (e.g., bombing, logistics, finance, etc.). The second objective (Objective 2-Temporality) will synthesise the extent to which mental health difficulties pre-date involvement in terrorism within prevalence studies. Finally, the third objective (Objective 3-Risk) aims to further establish temporality by examining the extent to which the presence of mental disorder is associated with terrorist involvement by comparing terrorist and non-terrorist samples.

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

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.

Counter-narratives for the prevention of violent radicalisation: A systematic review of targeted interventions.

Background: In the field of terrorism research, the violent radicalisation of individuals towards perpetrating acts of terror has been the subject of academic enquiry for some time. One core focus by social scientists has been the role of narratives in this process. Narratives have the ability to present a socially constructed version of reality which serves the interest of the narrator(s). In the context of terrorism, by depicting violence as a viable antidote to individual vulnerabilities, the narratives purported for propagandistic purposes have the potential to thwart perceptions of instrumentality (a key characteristic of violent radicalisation). In order to prevent this from happening, researchers and counter-terrorism practitioners have increasingly sought to explore the potential for counter-narratives; targeted interventions that challenge the rationalisation(s) of violence purported in dominant narratives which, in turn, reconstructs the story. However, there is overwhelming consensus in both government and academic spheres that the concept of the counter-narrative is underdeveloped and, to date, there has been no synthesis of its effectiveness at targeting violent radicalisation-related outcomes. Objectives: The objective of this review was to provide a synthesis of the effectiveness of counter-narratives in reducing the risk of violent radicalisation. Search Methods: After a scoping exercise, the literature was identified through four search stages, including key-word searches of 12 databases, hand searches of reference lists of conceptual papers or books on the topic of counter-narratives, as well as direct contact with experts and professional agencies in the field. Selection Criteria: Studies adopting an experimental or quasiexperimental design where at least one of the independent variables involved comparing a counter-narrative to a control (or comparison exposure) were included in the review. Data Collection and Analysis: Accounting for duplicates, a total of 2,063 records were identified across two searches. Nineteen studies across 15 publications met the inclusion criteria. These studies were largely of moderate quality and 12 used randomised control trial designs with varying types of controls. The publication years ranged from 2000 to 2018, with the majority of studies published after 2015. The studies represented a range of geographical locations, but the region most heavily represented was North America. In most cases, the dominant narrative(s) "to-be-countered" comprised of hostile social constructions of an adversary or "out-group". The majority of studies challenged these dominant narratives through the use of stereotype-challenging, prosocial, or moral "exemplars". Other techniques included the use of alternative accounts, inoculation and persuasion. Results: In terms of risk factors for violent radicalisation, there was some disparity on intervention effectiveness. Overall, when pooling all outcomes, the intervention showed a small effect. However, the observed effects varied across different risk factors. Certain approaches (such as counter-stereotypical exemplars) were effective at targeting realistic threat perceptions, in-group favouritism and out-group hostility. However, there was no clear reduction in symbolic threat perceptions or implicit bias. Finally, there was a sparse yet discouraging evidence on the effectiveness of counter-narrative interventions at targeting primary outcomes related to violent radicalisation, such as intent to act violently. Authors' Conclusions: The review contributes to existing literature on violent radicalisation-prevention, highlighting the care and complexity needed to design and evaluate narrative-based interventions which directly counter existing, dominant narratives. The authors note the challenges of conducting high-quality research in the area, but nonetheless encourage researchers to strive for experimental rigour within these confines.