***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: We included four trials (552 participants) that compared biphasic and monophasic waveform defibrillation in people with OHCA. Based on the assessment of five quality domains, we identified two trials that were at high risk of bias, one trial at unclear risk of bias and one trial at low risk of bias. The risk ratio (RR) for failure to achieve ROSC after biphasic compared to monophasic waveform defibrillation was 0.86 (95% CI 0.62 to 1.20; four trials, 552 participants). The RR for failure to defibrillate on the first shock following biphasic defibrillation compared to monophasic was 0.84 (95% CI 0.70 to 1.01; three trials, 450 participants); and 0.81 (95% CI 0.61 to 1.09; two trials, 317 participants) for one to three stacked shocks. The RR for failure to achieve ROSC after the first shock was 0.92 (95% CI 0.81 to 1.04; two trials, 285 participants). Biphasic waveforms did not reduce the risk of death before hospital admission (RR 1.05, 95% CI 0.90 to 1.23; three trials, 383 participants) or before hospital discharge (RR 1.05, 95% CI 0.78 to 1.42; four trials, 550 participants). There was no statistically significant heterogeneity in any of the pooled analyses. None of the included trials reported adverse events. It is uncertain whether biphasic defibrillators have an important effect on defibrillation success in people with OHCA. Further large studies are needed to provide adequate statistical power.
Output:

We searched the literature up to 10 September 2014 and tried to find all available research (published and unpublished) that compared these two types of defibrillators. We only included trials with a high-quality study design to avoid the possibility of inaccurate results. Four trials (552 participants) met the inclusion criteria of our review. Several included trials were potentially at risk of misleading results due to features of their study design. When we combined these trial results, we found that using the newer biphasic waveform defibrillators may be associated with lower failure rates of restarting a person's heart, but these results were imprecise. There was no difference in the number of people who were alive on arrival at the hospital or who were discharged from the hospital alive. No included trials reported on side effects or operator safety. We are uncertain as to whether biphasic defibrillators have an important effect on being able to restart a person's heart because the results were imprecise.