Authors' reply

EDITOR,--We are pleased that David A Fitzmaurice admires our efforts. By forcing us to be explicit, the practice of evidence based medicine often identifies issues over which reasonable doctors can disagree, such as the therapeutic range. The fourth step of evidence based medicine, “acting on the evidence,” involves clinical freedom and encourages the appropriate use of clinical responsibility, specifically to use the best available evidence when taking decisions about individual patients that consider all aspects of their care. Evidence based medicine does not force compliance with guidelines produced externally. With regard to an elderly woman at increased risk of haemorrhage, we disagree with Fitzmaurice's recommendation. The British Society of Haematology's guidelines are based on an earlier review,1 which amplifies the flaws in evidence available at the time of their use. The more recent …