People who went to playcentre or kindergarten in the early 1980s are now earning thousands of dollars more than those who did not, a report from the Christchurch Health and Development Study shows.
The Otago University project has found a persistent link between early childhood education more than 35 years ago and better academic achievement, higher incomes and more consistent employment in later life.
The report said 95 percent of the 1265 people in the study attended some form of early childhood education with 85 percent attending for more than a year, and nearly a third for two years or more.
The participants were born in mid-1977 and 93 percent attended early education between the ages of four and five years old, with 70 percent going to kindergarten and 17 percent to playcentre.
The report said those with two to three years of early childhood education were earning on average $50,200 a year by the age of 30, compared with $43,000 for those with none and $45,400 for those with less than one year of early education.
They had better verbal and maths skills than other children at school, were more likely to go to university, and had higher average academic achievement by the age of 30.
They were also less likely to become a parent or commit a property or violent crime during their teens.
The report said the better outcomes were likely the result of higher secondary school achievement of those who attended early childhood education.
Report lead author John Horwood said the key benefits now for people who participated in early childhood education in the early 1980s were in their socio-economic well-being.
"You will have had a slightly higher income trajectory across your life-course, probably slightly greater participation in paid employment across the life-course and those differences, they're not huge but they're consistent in the long-term, are going to translate into greater long-term well-being."
"What we see is clear evidence of small but pervasive benefits for a range of cognitive and academic attainment," he said.
"Children who attended early childhood education for two years or longer, did better at high school and scored slightly better on measures of cognitive ability and as adults they tended to come out being slightly better off socio-economically, have slightly higher incomes, be more likely to be participating in the paid workforce and so on."
Mr Horwood said there was far less evidence of long-term benefits in the participants' social and behavioural lives.
The study found 82 percent of participants attended early childhood education for an average of 7.7 hours when they were between three and four years old, and 93 percent attended for an average of 13 hours between the ages of four and five.
Mr Horwood said children tended to do better if they had more early childhood education.
"Those who attended for longer or those who attended for more hours as preschoolers appear to show greater benefits than those who attended for less or for fewer hours."
ECE benefits children 'of all backgrounds'
An associate professor at the University of Waikato, Linda Mitchell, said there was a clear link between quality early childhood education and benefits in later life.
She said it was difficult to know how much those benefits had changed since the early 1980s because the early childhood sector had changed a lot.
She said an early childhood curriculum and longer teacher training had been introduced since the study's cohort were preschoolers, and education and care centres rather than kindergartens were now the dominant form of early education.
While there had been some improvements in regulations and funding, quality was variable, she said.
Ms Mitchell said more research was needed, especially for children under the age of two, who were in early childhood care and education.
Kindergartens New Zealand chief executive Clare Wells said the study showed the benefits of early education were the same for children of all backgrounds.
"A lot of the discussion at the moment is that the most benefit from ECE is for children from challenging backgrounds or disadvantaged backgrounds, but actually what the report shows is that the benefits are widely spread right across socio-economic communities and ethnicity."