Participants in the 11 states — Arizona, Connecticut, Delaware, Florida, Idaho, Kentucky, Massachusetts, Nevada, New Hampshire, New Mexico and Vermont — answered at least 89 questions about demographics; unintentional injuries and violence; tobacco use; alcohol and drug use; sexual behaviors; body weight and diet behaviors; physical activity and other health-related topics.
A sample question addressing NSSI may read: “During the past 12 months, how many times did you do something to purposely hurt yourself without wanting to die, such as cutting or burning yourself on purpose?” with choice options of “0 times,” “1 time,” “2 or 3 times,” “4 or 5 times” and “6 or more times.”
Questionnaires were administered and collected during a single class period, according to the study.
What exactly is self-harm?
"Self-harm or self-injury means hurting yourself on purpose," according to the National Alliance on Mental Illness. "One common method is cutting yourself with a knife. But any time someone deliberately hurts herself is classified as self-harm. Some people feel an impulse to burn themselves, pull out hair or pick at wounds to prevent healing. Extreme injuries can result in broken bones."
It isn’t a mental illness, “but a behavior that indicates a lack of coping skills” that may be associated with illnesses such as borderline personality disorder, depression, eating disorders, anxiety or posttraumatic distress disorder.
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Overall, 17.6 percent of survey respondents in the University of Portland study reported at least one NSSI act in the previous year.
"The numbers are very disturbing," study co-author Nick McRee told BuzzFeed News. "They suggest that the behavior is not concentrated among a small number of disturbed youths, but in fact, it is a fairly common type of behavior among adolescents in general."
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The rate of boys reporting self-harm without wanting to die over the past year ranged between 6.4 percent to 14.8 percent. The rate for girls was twice as high.
In fact, in some states, such as Idaho, the rate of self-harm for teenage girls was as high as 31 percent.
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They were also more likely than boys to report experiencing most of the health risks believed to be associated with NSSI, authors wrote. Such health risks include depression, suicidal thoughts, forced sex and cyber bullying.
Still, more than 1 in 10 high school boys in the analyses reported NSSI.
Across the board, prevalence of NSSI appeared to decline with age. Among 14-year-olds, 19.4 percent reported at least one incident of NSSI. Among 18-year-olds, the rate dropped to 14.7 percent.
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“No particular racial or ethnic group is immune from NSSI, though rates were higher among Native Americans, Hispanics, and Whites than they were among Asians and Blacks,” authors wrote.
In fact, more than 20 percent of adolescents identifying as Native American reported NSSI, compared to just over 12 percent of African-American youth.
“Our findings indicate that the scope of NSSI among adolescents is so widespread that individual clinical and therapeutic interventions may be insufficient to address this public health problem,” report authors wrote.
The researchers hope school-based and community health programs will better address the identified risk factors. Additionally, they wrote, because many factors associated with NSSI can also be linked to other mental health problems, “efforts to prevent NSSI should be incorporated into broader efforts to address mental health among children and adolescents.”
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Some limitations the scientists addressed include lack of insights about the severity of injuries or how participants felt about their behavior, suggesting the evidence lacks in-depth analyses common in clinical samples.
Questionnaires also didn’t include questions about other factors associated with NSSI, such as family dynamics.
Future research should focus on whether the high rates of NSSI reflect a trend or just evidence of public recognition of the phenomenon, authors wrote. Additionally, researchers believe more investigation is needed to understand whether the observed NSSI decline by age continues beyond high school or has lasting effects.
Read the full study at ajph.com.
If you or anyone you know is self-harming, depressed, contemplating suicide, or if you are concerned for someone else, here are some helpful resources:
National Suicide Prevention Lifeline (24 hours): 1-800-273-8255
Text TALK to 741741 for anonymous and free counseling (24 hours)
RAINN sexual assault hotline: 1-800-656-4673
SAMHSA, confidential support for substance abuse help: 1-800-662-4357
Trevor Lifeline, suicide hotline for LGBT youth: 1-866-488-7386
Suicide prevention resources for parents, guardians and families
Suicide prevention resources for teens
Suicide prevention resources for survivors of suicide loss
More resources and programs at the Suicide Prevention Resource Center.