Human Factors
If roughly 80% of accidents involve human factors why is the EMS industry so fascinated with technology? Sure, technology is very useful in reducing accidents, but it isn't the whole picture. I'd like to see a national survey of EMS pilots done by a very competent organization that is capable of coming up with the right questions and collating the returns properly. Starting at the ground level seems the best approach.
Twin versus single engine? No statistical difference in safety that I know about. But, some cities and hospitals require twin engine helicopters for operation to heliports within their jurisdiction.