There are wide variations in the amount of money NHS trusts spend on individual diseases and healthcare conditions, a new report warns.
An analysis of primary care trust (PCT) spending over the past two years questions how consistently priorities are decided across the NHS, and raises concerns about the impact on patient care.
The King's Fund research finds that the biggest single chunk of money goes into mental health care - about £7 million, or 11 per cent of PCTs' total spending.
While it notes this is one of the government's top priorities, along with cancer care and heart disease, it warns that within this there are major regional variations.
In cancer care, for example, Sedgefield PCT spends £59 a head, far less than the £132 spent by Daventry and South Northamptonshire PCT. Meanwhile, Wyre PCT spends £173 per head on circulatory problems, compared to Bradford City's £74.
The think tank notes that as PCT funding from central government varies according to the needs, age and population of their particular area, as well as the cost of providing particular services, so does the spending within that trust.
But it finds that even when these changes are taken into account, there remain wide variations between how much PCTs are spending on the three key priorities. For example, cancer spending varies from three per cent to ten per cent of a PCT's budget.
One of the most stark contrasts in spending is in mental health, an area on which Islington PCT spends £406 per patient, compared to just £56 by Bracknell Forest.
Even when figures are adjusted to take into account individual needs of these trusts, spending in Islington is still nearly four times as much as in Bracknell Forest.
"This new data is very revealing, and raises serious questions about the consistency of decisions PCTs make about how much they spend on different diseases," said John Appleby, chief economist at the King's Fund.
However, he praised the Department of Health for introducing a system four years ago that meant PCTs had to start recording how much they spent on specific diseases, rather than simply on staff costs, hospital procedures and drugs.
"It is an extremely important initiative which should start to help answer vital questions about where the money goes, what we get for our investment in the NHS and how the NHS can improve value for money," he said.
Responding, health minister Lord Warner said: "This is not about a postcode lottery because money is allocated to primary care trusts on the basis of health need.
"Some variations in spending across the country are to be expected as people respond to the different needs of local communities."