Researchers at the University of Washington say they have uncovered data which shows that since 1980, official government statistics on the number of people killed by police is vastly underestimated, by more than half.

The federal government's National Vital Statistics System (NVSS) keeps official track of those killed in police interactions, and according to the researchers, the NVSS lists that number at 13,700 killed between 1980 and 2019.

But the researchers say they used three independent, open-source databases, Fatal Encounters, Mapping Police Violence and The Counted, to reach a far higher number: 30,800, or 17,100 more deaths than reported by the NVSS.

The study, published Friday in the Lancet, also says that Black men are 3.5% more likely to die at the hands of police than White men and Black women about 1.4% more likely to die than White women.

The senior author of the study, Mohsen Naghavi told ABC News, "Police violence and racism is really a public health problem."

The study also lays out a plan for the NVSS to overhaul how it keeps track of police deaths, pointing out that the same US states that are responsible for those deaths are also the ones responsible for reporting them. The report calls that a "conflict of interest", and also says that coroners who make the determination of "homicide" on a death report run the risk of miscalculation when it comes to police killings.

As for the racial disparity in police killings, the study says "Proven public health intervention strategies are needed to address these systematic biases."

The study mentions how high-profile police killings in the past year have spurred the Black Lives Matter movement and a greater interest in digging deeper into police killings, particularly of Black Americans.

The NVSS has yet to comment on the report./aa