Most stalkers aren't strangers, said lead researcher Kathleen Basile, Ph.D., a behavioural scientist with the Division of Violence Prevention, National Center for Injury Prevention and Control.
Women, younger adults and those who are single, separated or divorced are most at risk. That younger adults are more likely to be victims "goes along with what we know about violence in general," Basile said.
African-Americans have significantly lower odds of being stalked than whites, data showed. Basile said the reasons aren't clear, but that there may be differences in how people report stalking.
"Stalking continues to be a public health problem at a magnitude comparable to that measured in 1995 to 1996 [in the National Violence Against Women study]," the new study found.
"Women should be aware of the potential for stalking by an intimate partner, particularly when that intimate partner is physically or sexually violent," said Basile. Previous research has shown that for female victims, current and former spouses and partners are the most common perpetrators.
When men are stalked, it's more likely to take place outside of relationships, by acquaintances or strangers.
Conducted from 2001 to 2003, the telephone survey covered a range of injury-related topics and yielded 9,684 responses almost equally divided between women and men.
Stalking was defined as "ever being followed, spied on or communicated with, without consent, at a level perceived to be somewhat dangerous or life-threatening [not including dealings with bill collectors or salespeople]," for more than a month.
Whether stalking lasts several months or continues for years depends on the motivation of the perpetrator, according to Mindy Mechanic, Ph.D., an associate professor at Cal State University at Fullerton.
"A delusional individual — like a celebrity stalker — is different from a socially unskilled, awkward, poorly put-together individual who thinks that a neighbor who says 'Hi' in the hallways is romantically interested in them," Mechanic said.
Mechanic reiterates that the most dangerous stalker is someone who is or has been in a relationship with the victim. "In the majority of homicides involving intimate partners, stalking was another tactic, another tool in the abusive armamentarium of the stalker."
However, "most stalking does not end in homicide or even violence," she said. "The perpetrator is arrested, hospitalized, moves away, gets tired of it or finds another victim."
"You get involved with people and don't know that they have the capacity to stalk," said Deborah Prothrow-Stith, M.D., associate dean at Harvard School of Public Health. "It can be flattering when people are possessive — but there's a line."
Women need to be taught the warning signs of stalking, Prothrow-Stith said, and "how to "engage the police and put out a restraining order if stalking occurs. These signals will help some stalkers stop."
"If stalking were random stranger violence, policing would be the focus of public strategy," Prothrow-Stith said. Instead, she said, "prevention — not just responding — is the best we can do as a society."