The report finds people who suffer cardiac arrest are less likely to die in subsequent years when bystanders performed CPR using chest compressions only.
This backs previous research that found no short-term survival benefit in victims given compression-only CPR instead of the standard that involves mouth-to-mouth resuscitation.
The American Heart Association also recommends the simpler form. It says especially for bystanders who may feel so intimidated by the prospect of combining chest compressions with rescue breathing that they give no aid at all.
This latest study appears in the journal Circulation.