The Government is standing by data it used in deciding which Canterbury schools should close or merge as a result of population shifts following recent damaging earthquakes.
An interim decision has been announced on Monday to close seven primary or intermediate schools and merge 12. If they proceed, the closures will affect 670 children and take place from the end of this year.
The Labour Party on Monday questioned the demographic information used to make the decisions.
It said the closing and merging of schools is happening too quickly and more time should be given for the South Island city's population to settle following the quakes.
Acting education spokesperson Chris Hipkins said the information used is not based on solid data, with some schools slated for closure are actually reporting increases in their rolls.
"Schools are still reporting major errors in their data and in some cases the Ministry of Education are claiming that school rolls have decreased, where actually the principals are saying, 'No we've got more enrolments now than we did have last year'.
"So I think some of these decisions may well be quite premature."
Mr Hipkins said shortening the timeframe for when schools will close will cause unnecessary disruption for children and their parents.
But Earthquake Recovery Minister Gerry Brownlee says the data is sound.
Mr Brownlee said on Monday it is possible to predict population growth, based on a number of factors, including applications to build homes in new subdivisions on the outskirts of the city.
"Certainly, the population here is going to grow, we know that. We can predict by way of the movement that we've got to new subdivisions - the urban development strategy being a significant guide to that - where those new populations are likely to grow, and that has been factored into that."
Some 4500 primary school-aged children have left Christchurch since the quakes, he said.
