Abstract
BACKGROUND: Workplace bullying is a widespread and serious public health concern, affecting a substantial proportion of workers globally. While its consequences for mental and physical health are well established, consistent personality-based predictors of perpetration remain unclear. The Dark Triad personality traits, including Machiavellianism, narcissism, and psychopathy, are conceptually linked to interpersonal aggression but prior evidence is fragmented. METHODS: We conducted a systematic review and meta-analysis following Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines (Open Science Framework, DOI: 10.17605/OSF.IO/FWQ73). PubMed, PsycINFO, Embase, Scopus, and Web of Science were searched to 2 September 2025. Eligible studies reported associations between Dark Triad traits and workplace bullying perpetration among working-age participants. Random-effects models using Fisher's z-transformed correlations generated pooled effect sizes. Risk of bias was assessed using an adapted Joanna Briggs Institute checklist, and certainty of evidence graded with Grading of Recommendations, Assessment, Development and Evaluations. FINDINGS: Of 89 records screened, 16 met inclusion criteria, and nine contributed to meta-analysis. All traits were positively associated with bullying perpetration. Psychopathy showed the strongest pooled correlation (r = 0.53 [95% CI 0.28-0.71]), followed by narcissism (r = 0.40 [95% CI 0.26-0.52]) and Machiavellianism (r = 0.35 [95% CI 0.13-0.53]). Heterogeneity was substantial (I (2) > 90%). Narrative synthesis indicated contextual moderators including organizational climate, justice perceptions, and identity threat-shaped trait expression. INTERPRETATION: Machiavellianism, narcissism, and psychopathy are robust predictors of workplace bullying perpetration, with psychopathy most strongly implicated. Preventive strategies should integrate personality-informed leadership development with organizational safeguards. Workplace bullying should be prioritized as an occupational hazard and public health issue. SYSTEMATIC REVIEW REGISTRATION: https://osf.io/tvfkc/overview.