Public Policy Editor
A key plank of the Government's health policy was holed yesterday with the publication of a study commissioned by the NHS which casts doubt on the assumption that bigger is better.
Smaller general hospitals and units are being closed to concentrate services into larger, centralised "centres of excellence" in the belief that health outcomes - the quality of treatment and the death and complication rates - will improve.
The moves are partly based on dozens of studies both in Britain and the US which have conclued that high-volume produces better outcomes for a whole range of conditions and procedures from hip replacement to hysterectomy and by-pass surgery. But a review of the studies by the NHS Centre for Reviews and Dissemination at the University of York has concluded that the quality of the work is poor. The apparent gains have been inflated by poor adjustment of the results to allow for the differing types of case that are handled in high and low-volume hospitals.
Hospitals carrying out more procedures have tended to admit less severely ill patients and thus have better outcomes, but too little allowance has been for that in judging the results.
"There is little evidence to suggest that merging hospitals to create larger units will result in improved outcomes over time," Trevor Sheldon, director of the centre said.
The finding comes as smaller hospitals are being merged in almost all of Britain's big cities and some countries are starting to say that certain types of operation can only be carried out in licensed hospitals. Yet the report says that the belief that high volume reduces costs and improves the quality of care "is not well supported by the evidence".
A surgeon undertaking a procedure 15 times a year may well perform better than one doing it only twice. But there may be little difference between that and operating 50 times - and quality may fall if a surgeon becomes bored or rushed, or hands the work over to junior staff.
High-volume surgeons may also operate to better protocols, the report says - so if other surgeons adopted the same clinical guidelines the quality of their work might improve, closing the apparent gap between larger and smaller units.
The greater travel and time involved in getting to fewer centres of excellence may also exclude those who do not have easy access to transport - the elderly, mothers with pre-school children, adolescents, low-income families and the disabled.
"We are not saying the policy is wrong," Mr Sheldon said. "But we are saying we and the policy-makers who are rushing ahead with this approach do not, in fact, have the evidence to support it. A lot of this is based on faith and assumption."
Teaching and other large hospitals also have an interest - almost a vested interest - in the approach, he said. "But we need to be cautious about assuming that improvements in health care will automatically follow."
At the least, when changes are made careful monitoring should follow, including studies of whether equity of access is maintained.
t Relationship between volume and quality of health care: A review of the literature; CRD Report 2; NHS Centre for Reviews and Dissemination, University of York, YO1 5DD; pounds 5.Reuse content