Hospital trusts are being urged to adopt new guidelines designed to prevent blood clots that kill up to 25,000 people a year.
The guidance published by the Department of Health last week includes a checklist for health professionals but its use is not compulsory. It follows concerns trusts are not doing enough to screen patients for venous thromboembolism.
Chief medical officer Sir Liam Donaldson sent a letter in April 2007 highlighting advice on preventing the condition. This May HSJ revealed that 59 per cent of trusts had still not acted a year on.
Sir Liam said the challenge was to find a systematic approach to identifying high risk patients. But thrombosis charity Lifeblood warned the guidance would have impact only if taken up by hospital managers.
Parliamentary thrombosis group chair John Smith (Lab) said: "There are no excuses for NHS trusts not to enforce risk assessment in hospitals."
A DH spokesperson said there were no plans to make the assessments mandatory.