Pokémon GO killed at least two people and spiked rates of car accidents and injuries, according to a study of the game's impact on just one United States city.

“Death by Pokémon GO” (PDF), by a pair of researchers from Purdue University's Krannert School of Management, says the game caused “a disproportionate increase in vehicular crashes and associated vehicular damage, personal injuries, and fatalities in the vicinity of locations, called PokéStops, where users can play the game while driving.”

The researchers drew that conclusion after analysing “nearly 12,000 detailed police accident reports for Tippecanoe County, Indiana, over the period of March 1, 2015, through November 30, 2016.” That date range spans more than a year of normal conditions on the County's roads, plus nearly five months of data from Pokémon GO's July 6th, 2016 debut. All accident reports offered time, date, location, value of damage, plus reports on injuries or deaths.

The game was of interest to the researchers because it features “PokéStops”, real-world locations at which players can replenish their store of weapons.

The authors therefore compared crash locations to PokéStop locations, conducted “difference-in-differences analysis that controls for a variety of possible confounding factors” and found “that the increase in the number of crashes at locations in the proximity of PokéStops that can be attributed to the introduction of Pokémon GO is 134 across the county over the 148 days that followed the introduction of the game.”

“This compares to a county-wide increase of 286 crashes during the same period,” the pair wrote. “Thus, the increase in crashes attributable to the introduction of Pokémon GO accounts for 47% of the increase in the total number of county-wide crashes.”

It gets worse: "Based on the assessments of damage in the police reports, the increase in the number of crashes in the vicinity of PokéStops results in $498,567 of incremental vehicular damage, or 22% of the increase in the total dollar amount of vehicular damage experienced county-wide over the 148 days following the introduction of the game.”

An extra 31 personal injuries were also recorded, and the pair concluded that “On an even sadder note, our analyses indicate that the county would have experienced two fewer traffic fatalities had Pokémon GO not been introduced.”

The paper extrapolated what that might mean nationwide and concluded “the increase in crashes attributable to the introduction of Pokémon GO is 145,632 with an associated increase in the number of injuries of 29,370 and an associated increase in the number of fatalities of 256 over the period of July 6, 2016, through November 30, 2016.” The authors valued those crashes and fatalities at between $2bn and $7.3 billion for the same period.

The paper also noted that the incidence of road accidents has increased, reversing a long downward trend, since the advent of the smartphone, but stopped short of recommending further regulation of phone use in cars because previous laws or education campaigns aimed at reducing use of mobile devices in cars have not been successful. The authors added that Niantic, the game's developer, had included pop-ups that advised players not to play while driving. ®