Future criminals could be identified as toddlers
Tantrums and lack of self control in toddlers is a sign they may grow up to be drugs addicts and criminals, claims research.
Badly behaved children as young as three are also the most prone to financial and health problems in adulthood.
Researchers believe that identifying youngsters at such an early age could be a cheap way of tackling a range of issues from drug abuse to prison overcrowding.
The long term study followed more than 1,000 children in New Zealand through their lives to see if there was a connection between early behaviour and success in adulthood.
The youngsters were assessed by teachers, parents, observers and the participants themselves on a range of measures including "low frustration tolerance, lacks persistence in reaching goals, difficulty sticking with a task, overactive, acts before thinking, has difficulty waiting turn, restless, not conscientious".
They were then followed up later in life to see how they had turned out.
Prof Terrie Moffitt and Prof Avshalom Caspi, of Duke University, North Carolina, said the impulsivity and relative inability to think about the long-term gave them more difficulty with finances, like savings, home ownership and credit card debt.
They also were more likely to be single parents, have a criminal conviction record, and be dependent on alcohol, tobacco, cannabis and harder drugs.
The New Zealand children with low-self control were more likely to make poor choices as adolescents including taking up smoking, having unplanned pregnancies and dropping out of school.
Naturally, this set them on a more difficult path.
Even the low self-control individuals who finished high school as non-smokers without kids showed poorer outcomes at 32.
Their health suffered with badly behaved youth most from breathing problems, gum disease, sexually transmitted disease, inflammation, overweight and high cholesterol and blood pressure.
Prof Moffitt said: "These adult outcomes were predictable across the entire spectrum of self-control scores, from low to high."
However the researchers said the good news was that self control could be taught – especially if the youngsters were caught early enough.
Participants who found a way to improve their self-control as they grew up fared better in adulthood than their childhood scores would have predicted.
Prof Caspi said: "This shows self-control is important by itself, apart from all other factors that siblings share, such as their parents and home life."
Professor Alexis Piquero, at Florida State University who was not involved in the research, said: "The good news is that self-control can change. People can change."
Prof Piquero, who studies the developmental roots of criminal behaviour, said there are many time-tested approaches that give parents and teachers the tools to teach self-control.
The successful programs practice decision-making, role-playing and learning the consequences of actions.
He said identifying low self-control as early as possible and doing prevention and intervention is so much cheaper than dealing with the fallout – prisons, drug programmes and personal economic failures.
"If you are just making a dollars-and-cents decision, it's a no-brainer," he said.