The implementation of NICE guidance on venous thromboembolism risk assessment and prophylaxis: a before-after observational study to assess the impact on patient safety across four hospitals in England.

Background: Venous thromboembolism (VTE) is a major cause of morbidity and mortality in hospitalised patients. VTE prevention has been identified as a major health need internationally to improve patient safety. A National Institute for Health and Clinical Excellence (NICE) guideline was issued in February 2010.