Air travelers wait in the ride share lot near a sign for Uber at Los Angeles International Airport on August 20 in Los Angeles, California. Photo: AFP

The light bulb moment for neurosurgeons came as they conducted patient rounds one morning in 2017.

"What we realized is that we weren't doing as many emergency surgeries on Friday and Saturday nights at two o'clock in the morning," Christopher Conner remembered with a smile from his hospital in the fourth-largest US city of Houston.

"This is probably because of Uber."

A study of the app-based ride-hailing service by researchers at University of Texas Health Science Center validates the theory and was published on June 9 in scientific journal JAMA Surgery.

It shows that use of Uber and similar services in Houston has reduced the number of traffic accident patients at the city's two main Level 1 trauma hospitals, plunging 20.1 percent to 1,527 in 2019 from 1,911 in 2007, despite an increase in the population.

On Friday and Saturday nights, the change is even more pronounced, with the number of such patients falling 23.8 percent since Uber joined the market in February 2014.

Data shows the reduction in number of car crash victims applies to one demographic: people younger than 30, with a 38.9 percent plunge in cases between 2013 and 2018.

The statistic of 23,491 traffic accident-related admissions at the two trauma centers in Houston dates back to 2007.

"We knew initially that ride share helped to limit drunk driving," National President Alex Otte told AFP. "We knew that but it's really nice to have the data that shows that."