“…Seven papers (8 studies) reported data based on closed source datasets (data compiled from restricted files held by the statutory services including health, security and law‐enforcement) or datasets based on a combination of closed and open sources (e.g., Duits et al, 2022; FBI, 2019; Gill et al, 2022; Perry et al, 2018; Thijssen et al, 2021; Weenink, 2015; Weenink, 2019). Some studies were based on interviews with terrorists or former terrorists in community settings (e.g., Bubolz & Simi, 2019; Simi et al, 2015; Simi et al, 2016), while others involved clinical interviews with terrorist offenders recruited through the criminal justice system (e.g., Bonsard et al, 2022; Candilis et al, 2021; Dhumad et al, 2020; Lyons & Harbinson, 1986; Merari & Ganor, 2020).…”