Inadequate trauma care is killing 20,000 Americans each year and causing billions of dollars in losses, researchers say.

Most states lack regional systems to treat people injured in motor vehicle or industrial accidents, falls, shootings, stabbings or drowning, a study shows.It has been 22 years since the National Research Council labeled trauma "the neglected disease of modern society," the study in today's Journal of the American Medical Association said.

Only two states, Maryland and Virginia, have all the elements needed for adequate emergency medical services to handle trauma under standards defined by the American College of Surgeons, the study found.

It said 19 states and the District of Columbia either had "incomplete statewide coverage or lacked essential components," while 29 states "had yet to initiate the process of trauma center designation."

Studies dating to 1979 show one-third of trauma deaths in hospitals not able to handle such cases are preventable, said the study, which was led by Dr. John G. West of St. Joseph Hospital in Orange, Calif.

Up to 20,000 Americans die needlessly each year because they are treated inadequately for trauma, West said Thursday.

Trauma costs the nation an estimated $113 billion annually, including lost wages. Twenty-five percent could be saved with adequate trauma care, he said.

Trauma centers differ from regular hospitals. They have a surgical team ready at all times to operate on critically injured patients. They also have advanced communications and transportation systems to get patients to the site as quickly as possible.

West said many hospitals resist cooperating with trauma care networks for various economic reasons.

In urban areas, hospitals tend to avoid being designated as a trauma center because many trauma patients are poor and can't pay, he said.

In non-urban areas, hospitals want to be designated as trauma centers so as not to lose business to rivals.