MPs on the health select committee have raised concerns about the government’s funding models for a reformed adult social care system.
During the first session of an inquiry into the future of adult social care, MPs said more information was needed on how the £16bn spent each year on social care was used.
"You are spending lots of money and we don't know where it's going and we can't measure it," said Labour MP Dr Howard Stoate.
"If you don't know what the level of unmet need is now we've got no chance of meeting need in 20 to 30 years time," he added.
The financial models used by the government to determine future funding of adult social care are due to be published early next month.
Alexandra Norrish, head of social care strategy at the Department of Health, said experts at the London School of Economics and Political Science have developed the models over the past three years.
She said the models provide detailed forward projections from 2014 to 2026 and are still being refined.
“We have put in a whole range of assumptions. Obviously we can’t cater for what we don’t know,” she added.
David Behan, director general of social care, admitted there has been no research on unmet need and the difficulty in any model was how to allow for this.
"The key issue is that demand for social care is elastic. The issue we are trying to sort out is that in these straitened economic times how elastic is that demand," he said.
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