There is no evidence to support psychological debriefing in schools after traumatic events such as violence, suicides and accidental death, which runs counter to current practice in some Canadian school jurisdictions, according to a commentary http://www.
Recent systematic reviews indicate that psychological debriefing of adults does not prevent post-traumatic stress disorder and it may even increase the risk of this disorder. While there is little research on the effectiveness and safety of these interventions in schools, "the evidence clearly points to the ineffectiveness of these interventions in preventing post-traumatic stress disorder or any other psychiatric disorder in adults," write Magdalena Szumilas of the Sun Life Financial Chair in Adolescent Mental Health Team, Dalhousie University and coauthors.
Two programs, based on the empirically-supported principles of engendering feelings of safety, calmness, sense of self and community efficacy, connectedness and hope, show promise of effectiveness. Providing Psychological First Aid immediately after an incident and providing cognitive behavioural support for students with persistent distress weeks after a school trauma has ended may be helpful.
They urge that psychological debriefing not be performed after traumatic incidents in schools, and that more research is needed to assess psychological and mental health interventions prior to implementation in schools.