One in five people in Yorkshire will witness the collapse of someone needing CPR - yet 85% of us would be reluctant to step in to help cardiac arrest victims.
The British Heart Foundation says the main reasons are the lack of the skills and knowledge to perform CPR (41 per cent) and fear of causing more harm than good (48 per cent).
But experts warn that the benefits of performing CPR far outweigh any concerns because if you do nothing, the patient is likely to die.
The BHF released the findings to mark Restart A Heart Day - which is seeing thousands of young people given training in lifesaving skills.
Yorkshire Ambulance Service (YAS) NHS Trust has teamed up with the BHF and Resuscitation Council (UK) to join the national campaign aimed at training more than 150,000 young people across the UK in the largest ever CPR training event of its kind.
Calendar presenter Christine Talbot and former Leeds North West MP Greg Mulholland training join pupils of Leeds West Academy.