I once called 911 when my wife had an Asthma attack that left her unable to speak or stand. She was transfered from an ambulance to a paramedic about half way to the hospital. My insurance covered one as in-network but not the other. My wife was released a few hours later. I was young and it took me about 10 years to pay off the dept I owed. I am extremely hesitant to call an ambulance if the person can be encouraged to move under their own power. So much so, that I was asked to sign papers when a family physician suggested an ambulance. This rule looks like it helps.