A new Yale study may help psychologists deal with aggression among high-risk male youths.

Researchers from the Yale Child Study Center and Florida State University observed the behaviors of 119 adolescent juvenile offenders to understand the relationship between self-esteem and aggression levels. They found that both extremely low and extremely high levels of self-esteem were correlated with aggressive behaviors in male teens. The study suggested an alternative way of approaching juvenile offender rehabilitation: Instead of focusing exclusively on modifying behaviors, it may be helpful to target the way adolescents perceive themselves. The study was published in the October edition of the journal Child Psychiatry and Human Development.

“I felt this study was greatly needed considering risk factors for aggression are typically studied in less severe populations and then generalized to juvenile offenders,” said lead author Stephanie Smith, a post-doctoral research fellow at the Yale Child Study Center.

The research was conducted at a maximum-security residential facility for male youths who had a history of criminal behavior and had been found guilty of felonies. The researchers assessed the adolescents’ self-perception and level of aggression. According to Smith, the study differed from others in the field because it relied not on self-reported measures of aggression, but instead on behavioral observation.

But Yann Poncin, a professor in the Child Study Center at Yale, cautioned against describing self-esteem as the cause of violence.

“It might be one of the possible factors,” Poncin said. “But aggression is a complicated concept to which there is no straightforward answer.”

He noted that other potential factors might affect levels of aggression, pointing to culture, IQ and levels of community violence as possibilities.

James Comer, professor of child psychiatry at the Child Study Center, agreed, adding that there are multiple factors that contribute to aggression. Nonetheless, he said he is not surprised by the research results, since he believes that people with low self-esteem might be aggressive out of resentment toward their low status, and those with high self-esteem tend to be aggressive when their expectations are not met.

Comer added that the research might provide tips on how to more effectively interact with aggressive teenagers. It is more effective to address self-perception than the behavior itself, he said. When children behave inappropriately, adults should use the opportunity to help kids develop a sense of belonging and responsibility. He tied the implications to zero-tolerance policies in schools, which require teachers and administrators to punish students for even minor infractions, without taking into account extenuating circumstances.

“We are about to look for another way to work with young people, other than zero-tolerance,” he said.

Smith said that more work is needed to determine what factors are most responsible for aggressive behaviors among high-risk youth. Once researchers are able to identify those factors, clinicians will know what to target in treatment, she said.

As of 2011, more than 53,000 male adolescents were in juvenile prison.