Ref (type)	Population	Outcome, Interventions	Results and statistical analysis	Effect size	Favours
Rate of PTSD
Systematic review	238 people 2 RCTs in this analysis	Rate of PTSD 3 to 6 months with single-session individual psychological debriefing with no debriefing Absolute results not reported	RR 1.2 95% CI 0.84 to 1.71		Not significant
Systematic review	133 people Data from 1 RCT	Rate of PTSD 13 months with single-session individual psychological debriefing with no debriefing Absolute results not reported	RR 1.87, 95% CI 1.12 to 3.12	Small effect size	no debriefing