text: The study, in the journal JAMA Psychiatry, found that 55 percent of suicidal teenagers had received some therapy before they thought about suicide, planned it or tried to kill themselves, contradicting the widely held belief that suicide is due in part to a lack of access to treatment.
  
  The findings, based on interviews with a nationwide sample of more than 6,000 teenagers and at least one parent of each, linked suicidal behavior to complex combinations of mood disorders like depression and behavior problems like attention-deficit and eating disorders, as well as alcohol and drug abuse.
  
  The study found that about one in eight teenagers had persistent suicidal thoughts at some point, and that about a third of those who had suicidal thoughts had made an attempt, usually within a year of having the idea.
  
  Previous studies have had similar findings, based on smaller, regional samples. But the new study is the first to suggest, in a large nationwide sample, that access to treatment does not make a big difference.
  
  The study suggests that effective treatment for severely suicidal teenagers must address not just mood disorders, but also behavior problems that can lead to impulsive acts, experts said. According to the Centers for Disease Control and Prevention, 1,386 people between the ages of 13 and 18 committed suicide in 2010, the latest year for which numbers are available.
  
  “I think one of the take-aways here is that treatment for depression may be necessary but not sufficient to prevent kids from attempting suicide,” said Dr. David Brent, a professor of psychiatry at the University of Pittsburgh, who was not involved in the study. “We simply do not have empirically validated treatments for recurrent suicidal behavior.”
  
  The report said nothing about whether the therapies given were state of the art or carefully done, said Matt Nock, a professor of psychology at Harvard and the lead author, and it is possible that some of the treatments prevented suicide attempts. “But it’s telling us we’ve got a long way to go to do this right,” Dr. Nock said. His co-authors included Ronald C. Kessler of Harvard and researchers from Boston University and Children’s Hospital Boston.
  
  Margaret McConnell, a consultant in Alexandria, Va., said her daughter Alice, who killed herself in 2006 at the age of 17, was getting treatment at the time. “I think there might have been some carelessness in the way the treatment was done,” Ms. McConnell said, “and I was trusting a 17-year-old to manage her own medication. We found out after we lost her that she wasn’t taking it regularly.”
  
  In the study, researchers surveyed 6,483 adolescents from the ages of 13 to 18 and found that 9 percent of male teenagers and 15 percent of female teenagers experienced some stretch of having persistent suicidal thoughts. Among girls, 5 percent made suicide plans and 6 percent made at least one attempt (some were unplanned).
  
  Among boys, 3 percent made plans and 2 percent carried out attempts, which tended to be more lethal than girls’ attempts.
  
  (Suicidal thinking or behavior was virtually unheard-of before age 10.)
  
  Over all, about one-third of teenagers with persistent suicidal thoughts went on to make an attempt to take their own lives.
  
  Almost all of the suicidal adolescents in the study qualified for some psychiatric diagnosis, whether depression, phobias or generalized anxiety disorder. Those with an added behavior problem — attention-deficit disorder, substance abuse, explosive anger — were more likely to act on thoughts of self-harm, the study found.
  
  Doctors have tested a range of therapies to prevent or reduce recurrent suicidal behaviors, with mixed success. Medications can ease depression, but in some cases they can increase suicidal thinking. Talk therapy can contain some behavior problems, but not all.
  
  One approach, called dialectical behavior therapy, has proved effective in reducing hospitalizations and suicide attempts in, among others, people with borderline personality disorder, who are highly prone to self-harm.
  
  But suicidal teenagers who have a mixture of mood and behavior issues are difficult to reach. In one 2011 study, researchers at George Mason University reduced suicide attempts, hospitalizations, drinking and drug use among suicidal adolescent substance abusers. The study found that a combination of intensive treatments — talk therapy for mood problems, family-based therapy for behavior issues and patient-led reduction in drug use — was more effective than regular therapies.
  
  “But that’s just one study, and it’s small,” said Dr. Brent of the University of Pittsburgh. “We can treat components of the overall problem, but that’s about all.”
  
  Ms. McConnell said that her daughter’s depression had seemed mild and that there was no warning that she would take her life. “I think therapy does help a lot of people, if it’s handled right,” she said.
summary: A study in the journal JAMA Psychiatry found that 55 percent of young people who tried to kill themselves had received some mental health treatment beforehand.