One of the first studies to compare fundholding with GP commissioning - where family doctors work with health authorities to buy health care - has shown that both have advantages, and the two approaches do different things well.
Fundholding, where the GPs directly control their own budget, appears better at achieving short-term efficiency gains, the work by the London School of Economics shows. But locality purchasing, as GP commissioning is sometimes known, also brings advantages.
And as more fundholders band together in multi-funds, or enter total purchasing projects, where they buy all health care, the differences between the two models are becoming "rather nominal" the study found.
The study, led by Professor Howard Glennerster, co-director of the LSE's Welfare State Programme, concludes: "Neither political party should force either fundholding or locality purchasing as a universal solution."
Instead, commissioning should be given the same level of administrative back-up as fundholding enjoys - something health ministers have generally refused to do - while Labour should drop its plans to scrap fundholding.
The biggest single change which fundholding has produced is to "move general practice in from the cold", Professor Glennerster and his colleagues say. In 1990, family doctors did not feel involved in mainstream NHS planning. Since then there has been "a sea change" as fundholding was introduced and as GPs who did not want to join that scheme banded together to form purchasing commissions. "The extent to which GPs of all kinds are now involved in local health planning is quite new," the study says. And that change "is more important than the differences between fundholders and non-fundholders".
The research looked at how well family doctor groupings performed in six different health authorities. Overall the fundholders achieved greater changes. Those in GP commissioning groups, where the health authority still controls the budget, had greater frustrations - "an agent at one remove doing the purchasing on your behalf was less satisfactory for some GPs than acting directly".
But both achieved real gains for patients and "fundholders and locality groups do different things well". Commissioning groups were keener to see that all patients in the area gained from changes made, not just the patients of an individual practice.
"To push for universal fundholding or to seek to abolish it would seem unnecessarily destructive," the study says, "especially given our poor state of knowledge of the comparative advantages and disadvantages of the alternatives."
9 Alternatives to Fundholding, LSE Welfare State Programme, Paper WSP/123