(PhysOrg.com) -- It seems the ill-advised roads taken early in life are mostly one-way.
Ian Colman, an epidemiologist in the School of Public Health, has determined that people who exhibited bad behaviour in their early teenage years were far more likely than their well-behaved classmates to leave school early and experience problems as adults such mental illness, family conflict and financial troubles.
For his research, Colman utilized data from an ongoing, long-term study, known as the 1946 British Birth Cohort, which tracked 5,000 British citizens born within one week of each other in March 1946.
Colman focused on questionnaires filled out when the test subjects reached the ages of 13 and 15, and looked at indications of conduct problems at school, including disobedience, lying, truancy, responding poorly to discipline and being restless or daydreaming.
The results of the questionnaires were grouped into three categories-those with severe conduct problems, those with mild conduct problems and those with no conduct problems-and compared to the test subjects' outcomes as adults.
Of the 29 per cent of the study subjects who exhibited some form of teenage behavioural conduct, children with mild and severe behavioural problems were respectively twice and three times as likely to experience problems in adult life than their well-behaved counterparts.
"This research suggests that conduct difficulties in adolescence are not just a short-term problem that disappears when children grow up and mature," said Colman. "This study suggests that adolescent-conduct problems are often indicative of more serious problems in creating and maintaining positive social relationships, and this inability to function pro-socially has a long-term effect on the young adult's ability to maintain good mental health, stable employment and a happy family life."
While the findings, which will be published in the Jan. 24 edition of The British Medical Journal, were not unexpected, Colman says he was surprised by how effective even mild adolescent behavioural problems were in predicting a life of hardship.
"They were more likely to leave school early, be involved in a teenage pregnancy and/or in adulthood abuse alcohol, be divorced and have lower paying jobs," he said.
Colman said his study adjusts for factors that influenced this association, including the family social class, an impoverished environment, cognitive ability, symptoms of depression and anxiety and gender. He explained that while males were more often associated with undesired adolescent behaviour, females involved in the same test group who exhibited the same inappropriate teenage conduct also experienced negative outcomes as an adult at a similar rate, which more often, however, manifested themselves in the form of mental-health issues.
This research into problem adolescents builds on a mounting body of evidence that points to the financial price paid by society in terms of the resultant overarching cost of education, welfare, crime, and health care, the latter of which will be one of the focuses of Colman's next study.
"We want to look at how physical health translates into life expectancy because obviously this is painting a very poor picture and we suspect for some kids that will translate into an earlier death," he said.
Colman also plans to explore the silver lining that emerged in the study, which saw a good portion of problem adolescents right the ship.
"Not every kid has this terrible road in front of them," he said. "There are going to be success stories emerge from these groups.
"I think we need to look at what's different about those kids and single out what were the things that supported them in getting their lives back on track."
Provided by University of Alberta
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