The £250m programme to provide new GP-led health centres in every local area risks repeating the mistakes made when independent sector treatment centres were set up, academics have warned.
Birmingham University's health services management centre has found that primary care trusts are ill-equipped to commission services under the equitable access scheme.
Its analysis warns that potential providers could walk away from schemes if PCTs pass on too much financial risk. But PCTs that shoulder the risk themselves could end up paying for services that are underused - as happened with many treatment centres.
Report co-author Chris Ham said: "You're damned if you do and damned if you don't. The risk is you provide so much funding that it's a re-run of ISTCs [or] if you put most of the risk on providers, and they're not going to attract patients, they might pull out."
A number of corporate providers and GP-led companies are reconsidering their involvement because of concerns over the viability of the business model and contract terms, the researchers found.
Professor Ham said the problem was partly that patients were not given enough information.
"We don't think enough emphasis has been given to informing patients and the public about changing registration and making choice in primary care," he said.
One PCT in the study estimated over 20 per cent of its population would need to switch GP to ensure the viability of services commissioned under DH access schemes.
The report, which also covers smaller local GP tendering processes, highlights "significant gaps in [PCT commissioning] capacity and expertise", particularly technical procurement and legal skills.
Providers attacked the procurement process as "bureaucratic, lengthy and document-intensive". Some said PCTs "did not understand what they were procuring".
HSJ revealed in the summer that providers felt the equitable access scheme was "appallingly poorly managed".
The report says tendering for primary care contracts is causing "substantial transaction costs" and "only time will tell whether the benefits will outweigh the costs".
It advocates using regional procurement hubs, developing PCT commissioning skills and more work to ensure GPs and private providers operate on a level playing field.