To determine the extent to which implementation of an evidence based treatment, antithrombotic treatment in atrial fibrillation, is possible in general practice.
Audit and qualitative study of patients with atrial fibrillation and an educational intervention for patients judged eligible for antithrombotic treatment.
South east England.
56 patients with a history of atrial fibrillation.
Assessment and interview to ascertain patients' views on antithrombotic treatment.
Main outcome measures
Number of patients receiving antithrombotic treatment.
Out of 13 239 patients, 132 had a history of atrial fibrillation of which 100 were at risk of thromboembolism. After the study, 52 patients were taking warfarin. Of the remaining 48 patients (of whom 41 were taking aspirin), eight were too ill to participate, 16 were unable to consent, four refused the interview, and 20 declined warfarin. Patients declining warfarin were inclined to seek a higher level of benefit than those taking it, as measured by the minimal clinically important difference. Qualitative data obtained during the interviews suggested that patients' health beliefs were important factors in determining their choice of treatment.
Patients’ unwillingness to take warfarin seemed to be a major factor in limiting the number who would eventually take it.
Key messagesAfter a structured intervention only half of a group of apparently eligible patients ended up taking warfarin for their atrial fibrillationImplementation of warfarin treatment for patients with atrial fibrillation was constrained by patients who were either too ill to take the drug or were unable to give consentThese constraints are compounded by the unwillingness of patients to reduce their risk by taking a proved drugThe number needed to treat, a key statistic in evidence based medicine, probably often overestimates the value of treatment in routine general practice and may not be sufficient to persuade patients of the benefit of treatment