Story highlights Study: 27 categories of the 50 indicators of violence and crime improved for kids

Children of all socio-conomic backgrounds were safer

Sociologists don't know why these rates have gotten better

Despite all the national headlines about school shootings and other violence, life has actually gotten a lot safer for American children, according to a new study.

Instances in which children were the victims of crimes such as assaults or violence such as bullying have declined significantly, according to the study, which appears in the most recent edition of the JAMA Pediatrics

Researchers compared rates of 50 different types of violence and crime over time. Of those categories, 27 saw significant declines between 2003 and 2011.

Children, regardless of race or social class, are victimized at higher rates than adults, according to the U.S. Department of Justice. Some children in this country also witness violence on a daily basis, which can have long-term psychological consequences.

The recession didn't reverse the trend, and that's unusual. Historically , more violence and crime occurs during economic downturns.

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"We often expect stress and dislocation that happens during a recession can exacerbate conflicts and crime and violence, but it seems not to have been the case for the most part in the most recent recession," said the study's lead author David Finkelhor.

"This study confirms what we have noticed from a variety of other sources that children's safety has improved since 2003," said Finkelhor, director of the Crimes Against Children Research Center at the University of New Hampshire.

This was true even for children of low-income families who live in neighborhoods where violent crime rates are disproportionately high. Children of color also were safer, according to this study.

The results do mirror the larger trend that some sociologists call " the great crime decline ." Rates of violence in general have decreased since the 1990s, and experts don't know exactly why.

Finkelhor and his co-authors shared a few theories on why violence against children has declined.

One is that many public health programs specifically designed to curb violence against children work. Studies show some programs, which include anti-bullying techniques and domestic violence awareness initiatives, have had success.

Another theory is that more people are on psychiatric medicine that reduces aggressive behavior. The study showed 5.6% of children were taking psychiatric medication in 2008; by 2011, that had increased to 7.8%. More adults are also taking medication for depression and anxiety, which may also reduce family violence.

Finkelhor thinks technology may also play an unexpected role in violence reduction.

More children have cell phones, he said, which means more can call for help if they sense danger.

Social media may also play a role. "A lot of people think that the Internet made kids more vulnerable and has induced them into taking more risks. There may be some of that," Finkelhor said. It can also open kids up to an avenue of online bullying.

But with so many kids preoccupied with social media, the risk-taking behavior that comes along with adolescence may now be more in the virtual realm than in reality.

"If they are taking those risks in their bedroom, there may be a delay in their actual behavior," Finkelhor said, which can leave youths vulnerable to violence or crime.

Kids who spend a lot of time online also have a lot less time to be bored. Boredom can led to crime and violence for some children, Finkelhor theorized.

The study should give the public hope, said John Lutzker , director of the Center for Healthy Development at Georgia State University, who wrote an editorial accompanying the study.

"Of course, one instance of violence is too many, one child being bullied is too many," Lutzker said. "But these results show we are making tremendous progress."

He urges people to keep this trend in perspective, however. "The United States is far more violent than other developed countries, and we hold the record for the number of people we incarcerate," Lutzker said.

He and Finkelhor noted the study lacks comparative data about children under age 2. Statistically, those children are at a higher risk for death from maltreatment.

That data are now being collected, Finkelhor said, so researchers should have a better understanding of violence and its impact on this age group in the future.

Both academics are hopeful that this positive trend can continue.

"Behavior we see in childhood often continues into adulthood," Finkelhor said. In other words, if children of this generation experience less violence, in theory they will be less violent to the next generation, and so on.

Finkelhor said he thinks the findings hint at a broader trend that tends to get overlooked in the modern media landscape.

"I think there is a kind of alarmism which tends to pervade a lot of coverage and certainly when I talk with my undergraduates, they think things are getting worse," Finkelhor said.

Other positive trends for children, he believes, have been overlooked -- the high school dropout rate is decreasing, the number of missing children is down, overall teen sexual behavior is getting more responsible, the use of contraception is up, teen pregnancies are down, and a variety of mental health indicators for children are moving in a positive direction with improvement in the suicide rate.

"I haven't seen this get enough attention," Finkelhor said. And he makes a prediction: "We may look back at this era in a much more positive light than we feel about it now as we are currently going through it."