The analysis of 36 studies, conducted by researchers at the University of Alberta and the Ontario Centre for Excellence for Child and Adolescent Mental Health in Ottawa, was published Monday in JAMA Pediatrics.
"Within the depression category, there was a consistent association between exposure to cyberbullying and an increased likelihood of depression," said lead author Michele Hamm, a research associate at the Edmonton university.
The studies showed that females are more often the objects of cyberbullying than males and that relationship issues — between friends or in a dating situation — are often at the heart of the electronic attacks.
"We did pull out a few themes," said Hamm. "Girls tended to be bullied about their popularity and appearance, and boys tended to be bullied more with homophobic comments and (about) their physical abilities."
The research found the prevalence of online bullying ranged from about five per cent to 74 per cent of respondents, depending on the study, for a mean rate of 23 per cent, or about one in four.
Effects of being bullied included becoming withdrawn, angry or embarrassed, she said. Among those who were persecuted, there was a tendency for grades to drop off and school attendance to fall.
Rob Frenette, co-executive director and co-founder of BullyingCanada Inc., said depression is a common response to being cyberbullied and the effects can persist into adulthood, especially if the perpetrator continues their campaign beyond high school or university, for instance.
The stress of being bullied can lead to disturbed sleep, nightmares and sleepwalking. Those on the receiving end may remove themselves from social media and other online interactions, he said Monday from Fredericton.
In some cases, they "remove all technology from their lives. They just don't feel safe dealing with somebody who is potentially able to access them 24-7 through a computer screen."
Hamm said children and teens in the studies who were tormented online often found a passive way of coping, either by blocking the sender or by trying to ignore their messages.
"What we did not see a lot of was telling people," she said. "Kids often did not tell their parents or their teachers. If they told anyone, it tended to be a friend.
"One theme that did keep recurring was that kids were afraid their parents would take away their Internet access. This is a huge source of connection with their friends, so they didn't want to be cut off."
Frenette said a child or teen who's being bullied online by a classmate should tell their guidance counsellor or principal, and parents should also be told when the bully is someone outside school. In that case, it may be prudent to involve the police, as it's possible in certain cases that Criminal Code charges could be laid.
"It's very important to let your parents know what's going on," he advised young people.
"The other side of that is parents need to understand that the best solution is to not completely unplug your child from all social media. That way you're punishing your son or daughter for something they didn't do."
Hamm said the research review provides a profile of cyberbullying and the context in which it occurs, which could be used to help create prevention and management strategies.
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