Methods

Search strategy, screening, and data extraction

A search for empirical research with respect to mass victimization events was conducted through reputable search engines including PsycINFO, PubMed, OMNI, Google Scholar, and the Canadian Disaster Database (Public Safety Canada, n.d.). An Advanced Google Search was then conducted for each mass victimization event, using the key terms outlined in Table 1. For each event, the first five Advanced Google pages were searched, and relevant information was extracted. In addition to searching the grey literature, Covidence was used to identify relevant published papers on mass victimization events in Canada since 1975.

Table 1 lists the general search terms. The search timeline occurred between March 4 – April 17, 2025, and Table 2 lists the inclusion and exclusion criteria for the search.

Table 1. General database search terms

Table 1. General database search terms
Study terms Search terms
Mass Victimization Mass victimization, mass fatalities, mass deaths, mass shootings, mass stabbings, mass casualty, van attacks, shootings, stabbings
Canada Canada, Canadian
Location Ottawa, Saskatchewan, Vaughan, Moncton, New Brunswick, Alberta, Manitoba, Nova Scotia, Portapique, Ontario, Quebec
Specific mass victimizations Air India Flight 182, Ecole Polytechnique, Giant Mine, Vernon Massacre, Mayerthorpe, Ottawa shooting, Edmonton shooting, Moncton attack, Calgary stabbing, Quebec Mosque, Toronto van, Nova Scotia shooting, London truck, Vaughan condo
Lessons learned learnings, lessons learned, recommendations, inquiry, policy

Table 2. Inclusionary and exclusionary search criteria

Table 2. Inclusionary and exclusionary search criteria
Inclusionary criteria Exclusionary criteria
Canadian mass victimization event Non-Canadian mass victimization event
Published in English Published in languages other than English
Published between 1975–2025 Published before 1975
Lessons learned related to event i.e., formal inquiries and/or published lessons learned available to the public. No lessons learned related to the event i.e., no formal inquiry documents and/or published lessons learned available to the public.

Resources for this report include federal and provincial inquiries, coroner inquests, judicial reports, and government publications, peer-reviewed articles, and non-government publications. A qualitative analysis was conducted to identify any lessons learned and/or recommendations about (1) effective strategies for responding to victims of mass victimization events, and (2) prevention strategies for different types of mass victimization events.

All lessons learned/recommendations presented in this report are quoted or paraphrased directly from the original source materials. No recommendations have been generated independently by the authors.