Study: Teen violence spreads like a disease

It's long been said that violence begets violence, but a new study published Tuesday in the American Journal of Public Health has found that it's especially contagious among teens.

Researchers pored through data taken from the National Longitudinal Study of Adolescent Health, an extensive survey of more than 90,000 children in grades 7 to 12 that first began in 1994. They keyed in on a smaller group of in-depth interviews conducted every few years, allowing the researchers to track the social networks of nearly 6,000 children. What they found was that kids were more likely to participate in violence in the last 12 months if either their friends or siblings were also violent.

"We now have evidence that shows how important social relationships are to spreading violent behavior, just like they are for spreading many other kinds of attitudes and behaviors," study author Brad Bushman, professor of communication and psychology at Ohio State, said in a statement.

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Elsewhere, other research has long shown the contagious nature of violence. For example, people abused in their childhood being more likely to be abusive parents themselves.

In this study, not only did the link hold firm across different forms of violence, from relatively mild to life-threatening, but it didn't need especially close contact to show up. Even having a friend of a friend commit violence was associated with a greater risk of someone committing violence themselves, though to a lesser extent than with simply having a violent friend. And for the mildest form asked about, getting into a serious fight, the pattern could be seen through four degrees of separation (the friend of a friend of a friend of a friend).

It should be said the contagious effects of violence are impressive-sounding but need to be taken in context. For instance, though kids were 140 percent more likely to report pulling on a gun or knife on someone if their friend had done so, only 3 percent of kids at all said they did something like that in the past year (when asked about it in the second wave of interviews). Twenty percent said they had gotten in a serious fight and 6 percent said that they had hurt someone badly, with the likelihood of doing so jumping up by 48 percent and 183 percent respectively if their immediate friends had done it too.

Though studies like these can't prove a clear cause-and-effect links, Bushman and his Ohio State co-author Robert Bond, an assistant professor of communication, do think there are practical lessons in their findings.

RELATED: Most dangerous, violent cities in each state

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Most dangerous, violent cities in each state
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Most dangerous, violent cities in each state

43. Honolulu, Hawaii had 11.6 violent crimes per 10,000 residents.

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42. Boise, Idaho had 13.5 violent crimes per 10,000 residents.

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41. Fargo, North Dakota had 14.6 violent crimes per 10,000 residents.

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40. Eugene, Oregon had 15.3 violent crimes per 10,000 residents.

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39. Lincoln, Nebraska had 17.4 violent crimes per 10,000 residents.

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38. Sioux Falls, South Dakota had 20.6 violent crimes per 10,000 residents.

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37. Billings, Montana had 21.1 violent crimes per 10,000 residents.

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36. Norfolk, Virginia had 24.5 violent crimes per 10,000 residents.

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35. Providence, Rhode Island had 26.6 violent crimes per 10,000 residents.

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34. Manchester, New Hampshire had 28.9 violent crimes per 10,000 residents.

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33. Louisville, Kentucky had 30.2 violent crimes per 10,000 residents.

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32. South Bend, Indiana had 32.2 violent crimes per 10,000 residents.

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31. Tucson, Arizona had 32.4 violent crimes per 10,000 residents.

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30. North Charleston, South Carolina had 34.8 violent crimes per 10,000 residents.

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29. Tacoma, Washington had 36.6 violent crimes per 10,000 residents.

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28. Salt Lake City, Utah had 38.2 violent crimes per 10,000 residents.

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27. Des Moines, Iowa had 38.7 violent crimes per 10,000 residents.

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26. Pueblo, Colorado had 41.6 violent crimes per 10,000 residents.

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25. Tulsa, Oklahoma had 41.5 violent crimes per 10,000 residents.

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24. New Orleans, Louisiana had 42.7 violent crimes per 10,000 residents.

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23. Durham, North Carolina had 42.8 violent crimes per 10,000 residents.

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22. Jackson, Mississippi had 43.2 violent crimes per 10,000 residents.

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21. North Las Vegas, Nevada had 43.4 violent crimes per 10,000 residents.

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20. Wichita, Kansas had 45.5 violent crimes per 10,000 residents.

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19. Albuquerque, New Mexico had 48.2 violent crimes per 10,000 residents.

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18. Philadelphia, Pennsylvania had 49.1 violent crimes per 10,000 residents.

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17. Buffalo, New York had 50.2 violent crimes per 10,000 residents.

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16. Newark, New Jersey had 50.2 violent crimes per 10,000 residents.

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15. Odessa, Texas had 51.8 violent crimes per 10,000 residents.

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14. Tallahassee, Florida had 52.8 violent crimes per 10,000 residents.

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13. Anchorage, Alaska had 53.6 violent crimes per 10,000 residents.

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12. Springfield, Massachusetts had 54.4 violent crimes per 10,000 residents.

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11. Atlanta, Georgia had 55.7 violent crimes per 10,000 residents.

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10. Hartford, Connecticut had 55.8 violent crimes per 10,000 residents.

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9. Cleveland, Ohio had 61.5 violent crimes per 10,000 residents.

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8. Milwaukee, Wisconsin had 65.3 violent crimes per 10,000 residents.

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7. Stockton, California had 67.4 violent crimes per 10,000 residents.

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6. Baltimore, Maryland had 67.7 violent crimes per 10,000 residents.

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5. Rockford, Illinois had 76.3 violent crimes per 10,000 residents.

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4. Birmingham, Alabama had 82.8 violent crimes per 10,000 residents.

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3. Detroit, Michigan had 83.4 violent crimes per 10,000 residents.

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2. Memphis, Tennessee had 84.2 violent crimes per 10,000 residents.

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1. St. Louis, Missouri had 88.1 violent crimes per 10,000 residents.

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"If we can stop violence in one person, that spreads to their social network. We're actually preventing violence not only in that person, but potentially for all the people they come in contact with," Bond said.

As a model, the pair single out anti-violence organizations like Cure Violence, a non-profit doing work in several states and countries since 2007. Their program flat out compares violence to diseases like HIV/AIDS, and tries to adopt the same sort of strategies of disease control. Their three-step model involves finding and stopping potential outbreaks of violence, reaching out to people who are at most at risk and offering them rehabilitation or social services, and changing community perceptions in order to stop violence from being seen as normal.

So far, the results testify to their approach. A study out of Johns Hopkins University and funded by the CDC found that the program had reduced rates of shooting violence and homicides by 34 to 56 percent in the Baltimore communities where it was implemented starting in 2007.

The post Study: Teen Violence Spreads Like A Disease appeared first on Vocativ.

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