Between 2000 and 2011, there were 154 hospital-related shootings in the United States, with 235 people getting injured or dying as a result.

Shootings were more common in Southern states and larger hospitals - but other than that, "few patterns could be discerned to help profile vulnerable sites and situations," researchers reported in the Annals of Emergency Medicine.

Still, they said the findings should help dispel fears of hospital gun violence.

"We have to ask overall, how at risk are patients in the average hospital to be exposed to a shooting incident?" said Jay Wolfson, a patient safety researcher from the University of South Florida in Tampa who didn't participate in the research. "I think they're extremely rare."

Researchers from Johns Hopkins University initiated the study after a shooting event at their own hospital a year ago, when a man shot his mother's cancer surgeon, then shot and killed his mother and himself. The surgeon survived the shooting.

Emergency physician Dr. Gabe Kelen and his colleagues found the majority of shootings were targeted and involved a perpetrator with a grudge, a suicide or someone "euthanizing" a sick relative. There were 31 shootings in the emergency room, 29 in patient rooms and 35 in hospital parking lots. Hospital workers made up 20 percent of shooting victims.

Donna Gates, a nursing researcher from the University of Cincinnati, said that although shootings are very rare, other types of violence in the ER in particular are common.

"Harassment is an everyday experience for a lot of these people," she told Reuters Health of the ER staff.

Gates, who wasn't involved in the new study, is currently testing interventions in ERs to reduce assaults, such as making procedural changes, creating a more secure environment and educating workers.

"You're not going to get to a zero rate of physical violence against health care workers in settings such as emergency departments, but obviously there are ways to reduce that rate," she said.

Kelen agreed. "As we did, hospitals can convene a panel of experts after to examine and put in place any new security precautions. Detection of unusual behavior, and de-escalation training of personnel may be useful," he told Reuters Health in an email.

He and Wolfson both said installing metal detectors is often not feasible for hospitals. What's more, not all guns involved in shootings are brought in by the perpetrator - in a quarter of the ER shootings in the study, a security officer's gun was taken and used.

Wolfson said safety resources could be better used on training hospital staff to calm down agitated guests and patients and improving security.

Researchers agreed hospital visitors, patients and staff shouldn't be overly concerned about gun violence, as the rate of shootings is lower than at many other job sites.

"The likelihood of being shot in a hospital is less than the likelihood of being struck by lightning," Kelen said. "The vast majority of shootings involve a targeted victim and not random violence."

SOURCE: bit.ly/OJCDrT Annals of Emergency Medicine, online September 20, 2012.

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