By Anne Harding

NEW YORK, Mar 27 (Reuters Health) - To keep kids out of trouble, parents must hold the reins tightly during the middle school years, results of a new study suggest.

While criminologists agree that children with behavioral problems are more likely to become criminal adults, "only about 50% of antisocial children become antisocial adults," according to Ronald L. Simons of Iowa State University, and colleagues.

Simons and his research team set out to find out why some problem children become problem teens and others do not. They followed 149 boys and 157 girls and their families for 4 years. On average, the children were between 12 and 13 years when the study began. The researchers interviewed parents and children, and also observed family interactions.

One hypothesis holds that a difficult child will become increasingly involved with peers who are themselves "deviant" as he or she gets older, and that the quality of parenting can do little to change this path. But the researchers found otherwise.

In fact, the investigators found, difficult children make it tougher for parents to set limits or discipline their child, which in turn made it more likely that a child would start hanging out with deviant peers. These "oppositional/defiant" children threw temper tantrums, talked back, bullied other children, were selfish and blamed others. "They almost train you to be a bad parent," Simons told Reuters Health in an interview. "Over time you become more and more lax with your difficult child."

Better-behaved children, conversely, made it easier for their parents to be effective. Effective parents, the authors note, "show warmth and support, set standards for their children, monitor their behavior, engage in consistent discipline, use inductive reasoning to explain rules, and eschew harsh punishments."

The parents of the better-behaved children gave their children more freedom as they entered adolescence, but those with problem children got stricter instead. But the parents of the bad kids were still exerting much less control over their teens at the end of the study period than the parents of the well-behaved children were.

Simon and his colleagues looked at children on two extremes of the behavior continuum. "Most kids are probably in the middle," he noted.

"Our results show it's particularly important that the parent is monitoring and exerting control during those middle school years," Simon told Reuters Health. "That's going to predict what kind of behavior unfolds during the adolescent years."

He added, "During the adolescent years it's really tough to make a dent in your child's delinquency." But all is not lost for parents of troubled adolescents, Simon said. At this stage, these parents can still help their children stay on the straight and narrow by making sure they stay away from deviant and delinquent peers.

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