A new U.S. study suggests that early intervention to treating teenagers with clinical depression may help prevent episodes of chronic cases that will haunt them throughout adulthood. The study published in the Journal of the American Medical Association (JAMA) is the largest to date showing that a relatively modest intervention goes a long way to prevent episodes of depression in high-risk teens. The study involved 316 adolescents, ages 13 to 17, in four cities. All of the teenagers had a history of depression or current symptoms that just fell short of a clinical diagnosis. The teens also had at least one parent who had been diagnosed with depression. Half the teenagers were randomly assigned to a prevention program that consisted of eight weekly group sessions of cognitive behavioral instruction (CB) lasting 90 minutes each, plus six follow-up sessions that met once a month. The other half of the volunteers were assigned to a control group that got "usual care," meaning they were free to seek help from whatever resources were available to them in their community - as were the teens in the experimental group. There were no differences between the groups in terms of the types of services they chose on their own. The teenagers were followed for nine months. Less than a quarter (21.4 percent) of those in the CB program went on to have an episode of depression, compared with about a third (32.7 percent) of those in the control group. The results were far more dramatic for teens whose parents were not actively suffering from depression: only 11.7 percent who went through the program had an episode of depression during the nine-month follow-up. The CB sessions focused on teaching the kids to think more realistically - and less catastrophically - about their problems and experiences. "It's what we call the ABCD model," explains lead author Judy Garber, professor of psychology and human development at Vanderbilt University. Under the guidance of a social worker or other trained professional, the teens discuss A, an activating event, like a breakup with a boyfriend. Next they explore B, beliefs and thoughts about that event, like, "It's all my fault." Then they look at C, perceived consequences of the event: "I'll never find another boyfriend." And finally and critically, they engage in D, disputing their thoughts and assumptions by asking questions like, "Am I being realistic?" or "Would other people see it the same way?" Working in small groups of three to 10 works well for adolescents, says psychologist Gregory Clarke, who pioneered the program and is a co-author of the study. "The group can be almost a Greek chorus to bounce ideas off of, " explains Clarke, who is a senior investigator at Kaiser Permanente's Center for Health Research in Portland, Ore.