In planning the roll out of new services, the state government said it relied upon a combination of 2006 census data and Office for Economic and Statistical research, which estimated the population of four-year-olds in a statistical local area.
It also used vacancy rate data from the Australian Government Department of Education, Employment and Workplace Relations.
Meanwhile, Childcare Queensland — an umbrella body for many of the state's privately run long day care centres — provided its own research that suggested vast disparities in the vacancy rates of centres across Queensland.
An acute example was in Cairns, where the group's research — relying on respondents to an annual survey — showed at least 470 vacancies per week.
"We're just surviving," said a spokeswoman for the private Sunshine Child Care and Learning Centre in Aeroglen, who gave her name only as Dawn.
"We have 72 per cent occupancy. But Cairns is not a very big area."
A spokesman for Childcare Queensland, Peter Price, said the group initially welcomed the government plan to improve access to early childhood education in Queensland.
"We thought, this is great because in all the areas of need there will be more (centres) being built," Mr Price said, adding that politics could have played a part in decision-making.
"Politicians lobby, particularly with a state election coming up. (And) they don't look at the reality.
"And you get silly situations where there are a lot of vacancies and the government announces that they're going to build a centre.
"It's another ABC debacle all over again, essentially," Mr Price said, a reference to the collapsed child care group run by entrepreneur Eddy Groves.
Child care Queensland's president, Gwynn Bridge, warned in 2008 of the impact of the new centres on existing services, writing in an editorial on the Care For Kids website that, "should these centres begin to appear in areas where services are experiencing low occupancy rates, it is a concern that we will see market failure of existing services. Already some state/territory governments are building early learning services next door to or in close proximity to existing services."
Graham Sagar, the group's treasurer and himself a centre operator, agreed that while investment in child care was to be encouraged, poor planning posed risks to existing services.
"If an area needs a centre and doesn't get one, that's an issue. What's a bigger issue is if an area doesn't need a centre and the state government decides to put one there."