When you're in need of a ride to the hospital do you call 911 or order an Uber?

It may sound like a silly question, but a recent study revealed that ambulance usage is dropping in the United States, and researchers believe ride sharing services like Uber are to blame.

A research paper released on Wednesday, showed the findings of David Slusky, a Department of Economics professor at University of Kansas, and Dr. Leon Moskatel of Scripps Mercy Hospital's Department of Medicine. The two compared ambulance usage rates in 766 U.S. cities both before and after Uber was introduced (between 2013 to 2015).

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After reviewing all the data, the researchers concluded that Uber's entry into cities reduced "per capital ambulance volume by at least seven percent."

How? Well, while you can't be sure your Uber will come with the luxury of trained medical professionals, Slusky and Moskatel noted that ambulances costs — which sometimes reach the thousands of dollars — are extremely unattractive and are likely a driving factor in seeking alternate transportation.

"They have to think about their health — and what it’s going to cost me," Slusky told The Mercury News.

Ridesharing apps also give passengers the opportunity to select a hospital, rather than being taken to the closest one. And based on location to the driver when ordering a car, those requesting an Uber can sometimes experience a shorter wait time than they would for an ambulance.

"We’re grateful our service has helped people get to where they’re going when they need it the most," an Uber spokesman told Mashable.

"It’s important to note that Uber is not a substitute for law enforcement or medical professionals. In the event of any medical emergency, we always encourage people to call 911."