Three trials were included in the review: two cluster randomised controlled trials (RCTs) and one non-randomised control trial. Numbers of events in the intervention arms ranged from 128 to 447 and numbers of events in the control arms ranged from 107 to 432. The two RCTs did not report information on randomisation. It was not possible to blind patients or responders in any of the trials. None of the trials reported a preset sample size. All of the trials used intention-to-treat analysis and had 100% follow-up for their participants.
Two trials reported no statistically significant benefit of survival to hospital charge with public access defibrillation using level one responders when compared with the control group (OR 1.6, 95% CI 1.0 to 2.6 and OR 1.3, 95% CI 0.8 to 2.2).
One trial reported that provision of public access defibrillation using level two responders was associated with a statistically significant improvement of survival to hospital discharge when compared with the control group (RR 2.0, 95% CI 1.07 to 3.77).