Information In Practice

The faults of expert reviews are already well known

BMJ 2003; 327 doi: (Published 31 July 2003) Cite this as: BMJ 2003;327:269
  1. D A Fitzmaurice, clinical reader in general practice (d.a.fitzmaurice{at}
  1. 1Department of Primary Care and General Practice, Medical School, University of Birmingham, Birmingham B15 2TT

    The authors are well known proponents of evidence based medicine and introduced the concept of patient oriented evidence that matters (POEMs) and disease oriented evidence in the early 1990s. The current study claims that the two main POEMS from the United Kingdom prospective diabetes study (UKPDS), namely that for patients with type 2 diabetes blood pressure control is more important than glycaemic control and that metformin should be first line therapy, are not well presented in review articles. It is odd, therefore, that they choose a “convenience sample” of review articles rather than undertaking a systematic review. Thus the search strategy is broad, and it is hard to claim that using the authors as reviewers is an independent process.

    Having said this, the point is well made that review articles, particularly those written by specialists, tend to be of dubious value, with authors selectively choosing evidence to support their own prejudices. I would argue, however, that most practising clinicians know this already, and my experience is that most UK primary care physicians are aware of the key messages, or POEMs, as described above. My perception, albeit limited, is that the experience of a patient with type 2 diabetes is much more likely to include metformin treatment, intensive blood pressure monitoring and control, and intensive management of dyslipidaemia than the historical reliance on haemoglobin A1c. This has happened despite the apparent dissemination of misleading information described by the authors.

    The paradox of using non-evidence based methods to discredit non-evidence based reviews is striking, and is similar to using a lecture method to impart the information that lectures are not the best method for disseminating information. If one were to apply information mastery to the current paper one would not get past the abstract (some would suggest the title). The message is important, however, that expert reviews cannot be trusted. Sackett has always been wary of experts and has recommended that once a person has become an expert he or she should change jobs. This information has obviously filtered through to the “coal face” as clinicians are acting much more on primary data than filtered expert opinion.

    The goal of the authors, to effect change through clinical research using clinically important end points rather than intermediate or “proxy” measures, seems to me to have been achieved despite rather than because of the dissemination of poor information described. We should perhaps question why these expert reviews continue to be published, given both their lack of rigour and their apparent lack of influence.


    • Competing interests None declared.

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