Of the inflation-adjusted $6.6 billion costs during the study period, Medicaid paid $2.3 billion, or 34.8%; Medicare paid $0.4 billion, or 6%; private insurers paid $1.32 billion, or 34.8%; and self-pay individuals paid $1.56 billion or 23.6%.

“We’re an outlier nation in terms of gun problems, and this only looks at a small part of the expense,” said David Hemenway of Harvard University in Boston who wasn’t involved with the study.

The study doesn’t include costs related to long-term issues such as spinal cord injuries and traumatic brain injury, as well as social or job-related costs, such as unemployment, sick leave, and psychological impact on loved ones, noted Hemenway, who directs the Harvard Injury Control Research Center.

“It doesn’t even begin to account for the real costs of losing a relative, spouse or community member,” he added. “Gun violence makes it impossible to live a good life in some of these places, especially when industry doesn’t want to move in and people are afraid to go out.”

As the first study to quantify firearm-related costs in about a decade, the data could have major implications for public policy changes and healthcare funding, said Konstantinos Economopoulos of Massachusetts General Hospital in Boston, who was not involved in the research. In the past 30 years of funding from the National Institutes of Health, for example, six awards have supported firearm-injury studies, he said.

“The financial burden . . . falls mainly on the shoulders of the government (through Medicaid) and the uninsured,” he told Reuters Health by email. “There is an ethical – but also financial – imperative need for an increase in funding for future research to tackle the ongoing epidemic of firearm-related injuries.”