Implementing evidence based medicine in general practice: audit and qualitative study of antithrombotic treatment for atrial fibrillation
BMJ 1999; 318 doi: https://doi.org/10.1136/bmj.318.7194.1324 (Published 15 May 1999) Cite this as: BMJ 1999;318:1324
All rapid responses
Dear Sir
I was interested by your pictorial depiction on page 1325 of stroke victims as sad faces and the unaffected as smiley faces.
Surely the stroke victims should have been depicted with half a sad face and half a smiley face?
Yours
Dr Philip M. Peverley Park Avenue Roker Sunderland SR6 9PU
Competing interests: No competing interests
To: The Editor, British Medical Journal
Dear Sir,
Re: Implementing Evidence Based Medicine in General Practice
In East Kent we have been running a project to implement evidence based medicine in general practice since April 1998. The project sets criteria and standards in thirteen disease areas, including atrial fibrillation, and participating GPs are supported in their work to meet the project standards.
As from 1st April 1999 175, out of 312 East Kent GPs, participating in the project, this accounts for 56% of the GP in East Kent and covers over half of the population.
In view if the work that we have been doing with practices in our project I was interested to read the article by Howitt and Armstrong (BMJ 199;318:1324-1327). We have discussed at some length, over the last twelve to eighteen months, the issues surrounding the application of evidence based medicine to individual GP/patient consultations, and how this affects and changes the practice of primary care medicine.
From our experience it is clear that a number of factors affect the take up of evidence-based care in primary care, and that patient choice is a significant factor. As a result of our discussions and as part of the ongoing development of our project we have developed, in conjunction with participating GPs, a working definition of what we call "informed dissent". This enables GPs to make exceptions in their reporting against project standards which allow for patients who refuse treatment after they have been informed of the nature and results of treatment, and the likely outcome of refusing.
We are currently collating the results of the first year of work in this project and we will be interested to see how patient choice has affected the implementation of evidence based medicine in primary care. We will be looking closely at variation between exceptions on grounds of patient choice between different practices and may eventually be able to throw some further light on this sensitive and complex area.
If any of your readers would like further information about our project and the issues it is raising they should contact either me on 01304 222247, or Dr Tony Snell our Medical Adviser on 01304 222240.
Yours sincerely,
Derek Mitchell Clinical Governance Manager East Kent Health Authority
Competing interests: No competing interests
Editor
I applaud Howitt and Armstrong's paper (1) which highlights the difficulties of translating apparently robust evidence into routine clinical practice, and their data is similar to my own experience. For many reasons patients and clinicians do not always agree on management decisions.The paper raises two important issues.
The first is that the evidence for the effectiveness of warfarin is based on secondary care data from highly selected populations. In short GPs are not convinced that the risk reduction for stroke is 68%. Until these data are confirmed within a primary care setting in an unselected population, especially in the elderly, suspicion of the data will persist.
The second point is on how to present data to patients. If patients are presented with a "warfarin bad: aspirin good" scenario, they are likely to choose aspirin. The data for aspirin's effectiveness is however even less robust than for warfarin and I would liken giving aspirin for atrial fibrillation to giving nedocromil instead of inhaled steroids for asthma, i.e; it doesn't work but makes the physician feel better.
The whole field of eliciting patient preferences is a difficult one but this paper has opened the door for others to begin to understand the factors which influence patients' decisions in this area. Indeed decision anlaysis (2),(3) suggests that patients' perceived utility to warfarin therapy is more important than their underlying risk of stroke in terms of choice of therapy. I look forward to seeing these issues resolved in the near future.
Yours faithfully DA Fitzmaurice (Senior Lecturer)
1. Howiit A, Armstrong D. Implementing evidence based medicine in general practice: audit and qualitative study of antithrombotic treatment for atrial fibrillation. BMJ 1999;318:1324-1327.
2. Naglie G, Detsky AS. Treatment of chronic nonvalvular atrial fibrillation in the elderly: a decision analysis. Medical Decision Making 1992;12:239-249.
3. Eckman MH, Levine HJ, Pauker SG. Decision analytic and cost- effectiveness issues concerning anticoagulant prophylaxis in heart disease. Chest 1992;102;538S-549S.
Competing interests: No competing interests
How were risks presented?
Antithrombotic treatment for atrial fibrillation: careful presentation of risks of therapy also important
EDITOR - While the results of Howitt and Armstrong (1) are somewhat interesting, the findings have uncertain clinical relevance and are in contrast to those of Sudlow et al. (2), who reported that most elderly patients with atrial fibrillation would accept treatment to prevent stroke.
In this context, the precise information provided to the patient is critically important in influencing their beliefs. Lack of detail on the information provided to patients about the antithrombotic drugs mars the study by Howitt and Anderson. While the authors have emphasised the value of a patient-centred approach in determining antithrombotic therapy in chronic atrial fibrillation and have carefully presented the clinical trial-derived benefits of warfarin and aspirin to patients in a pictorial fashion, an equally important methodological issue is the presentation of the risks of the drug therapy. It is only stated in the methods that ‘detailed information about aspirin and warfarin treatment was given’. What exactly does this mean? If the material consisted of the typical prescribing information for warfarin or even the equally daunting consumer medication information developed by pharmaceutical companies, it is not surprising that many patients were frightened off therapy.
Adopting a patient-centred approach to therapeutic decision making also requires that the potential risks of the therapy are carefully presented in a similarly patient-friendly manner to the possible benefits.
Gregory Peterson, Associate professor. School of Pharmacy, Faculty of Health Science, University of Tasmania
1. Howitt A, Armstrong D. Implementing evidence based medicine in general practice: audit and qualitative study of antithrombotic treatment for atrial fibrillation. BMJ 1999; 318: 1324-1327.
2. Sudlow M, Thomson R, Kenny RA, Rodgers H. A community survey of patients with atrial fibrillation: associated disabilities and treatment preferences. Br J Gen Pract 1998; 48: 1775-1778.
Competing interests: No competing interests