Clinical evidence is far more likely to influence health service commissioning than the views of patients or clinicians - but stands next to no chance if it runs counter to government initiatives, according to research to be published today.
The Accounts Commission study, based on the experience of Scotland's 15 health boards in implementing evidence-based healthcare, reports managers' concern about the lack of evidence available and suggests that access to the Internet and other electronic information sources is rudimentary in many boards.
Eleven boards reported that such access was limited either to a few PCs or only came via the board's library or resource centre (see table 1).
The report concludes: 'When boards were asked if they believe their planning is evidence-based, only two boards were able to agree fully, while another four felt that new developments and strategies are now evidence-based.'
Dr Kieran Walshe, senior research fellow at Birmingham University's health services management centre, believes there is a direct connection between complaints about lack of evidence and access to PCs and electronic data.
'Access to electronic resources is pretty dreadful, ' he says.
'It does not appear to be a lack of evidence but a lack of investment in library facilities. Only a small minority of staff can access information.'
In fact, while nine boards have their own library, not all have a librarian.
The rest use hospital library services.
And where there is no librarian, staff spend more time on literature searches which may then be of a poorer quality.
Perhaps not surprisingly there is strong pressure to carry on doing things as they have always been done, or to do what the Scottish NHS Management Executive decrees, even when it clashes with the evidence (table 2).
Evidence is only part of the picture, says Chris Loughton, teaching manager and research and development manager at Addenbrooke's Hospital, Cambridge: 'Evidence is important, but there are other external factors to be taken into account.'
Dr Walshe says the findings reflect reality. 'It is not surprising that people are going to obey the policies, but this makes it all the more important that the central policy drivers are more evidence-based, ' he says.
Dr Norman Waugh, consultant in public health medicine at Grampian health board and a member of the Accounts Commission advisory panel, has some sympathy with complaints about the quality of evidence available.
Medline is a common means of accessing information. 'But this is raw data, not evidence, ' he says.
There is still a shortage of readily available summaries, says Dr Waugh, and while the Cochrane Collaboration produces brief, reliable synopses for non-medics, that is just a start.
'It will take time to get round all the interventions, ' he says. 'It also doesn't address the issue of cost-effectiveness.'
Mr Loughton says there needs to be more training so that people feel at home with electronic resources.
'There needs to be someone who can synthesise information and store it electronically in a sympathetic way so that people can access it at the level they need, ' he says.
The report says public health departments play a key role in disseminating evidence in nine of the boards, while commissioning teams do so in just three.
Public health doctors have to change their attitude and see themselves less as mediators and more as enablers, says Dr Walshe.
'They have access to libraries and are the main users of the Scottish Healthcare Technology Assessment Centre, but other people need evidence just as much.
'In the longer term, public health doctors have to enable the commissioning directorate to access evidence for itself.'
Level of access to the Internet Number of health boards
All staff have access via their PCs 1
Most staff have access via their PCs 2
Access is limited to a few PCs 6
Access via health board library/ resource centre only 5
No direct access 1
'Evidence is very, very important when it is in your favour, ' one manager taking part in the study told the Accounts Commission.
And, says the report, although evidence is becoming more important in planning service changes, 'where contradictory evidence exists, or the evidence is open to some degree of interpretation, this can lead to 'evidence wars'.'
The commission found that evidence played a significant role in decisions about new drugs but was less influential in other areas.
Two boards said they had decided to fund Beta-interferon because of clinician pressure and not on the basis of the available evidence. A third gave the same reason for funding Sildenafil.
'Despite evidence that mass media health promotion campaigns do not impact on behaviour unless they include a 'call to action', one health board continues to support these in order to increase visibility and raise awareness.'
One board reported difficulty in joint working because its local authority wanted the drugs message to be, 'Just say no', despite evidence suggesting that this approach does not work.
Another board examined the evidence for hydrotherapy for arthritis but found it to be inadequate.
'However, the board agreed to fund the service because it was not costly (£4 per treatment) and had a strong placebo effect.'
The Implementation of Evidence Based Healthcare in Scottish Health Boards .