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News & Reports bva congress
Evidence-based medicine: can we trust the evidence? More and more nowadays vets are being encouraged to apply evidence-based medicine. But can the results of research be taken at face value? Giving the plenary Wooldridge memorial lecture at this year’s BVA Congress, Fiona Godlee, Editor-in-Chief of the BMJ, discussed why – and how – the results of medical studies should be questioned. How good is the evidence that we base our evidence-based practice on, and to what extent can we trust it? These were questions posed by Fiona Godlee, Editorin-Chief of the BMJ, as she delivered the Wooldridge memorial lecture at this year’s BVA Congress during the London Vet Show on November 21. While there had been a positive shift over recent years – in both veterinary and human medicine – toward choosing treatments whose efficacy had been scientifically proven, the underlying data and methodologies of these studies might be flawed, argued Dr Godlee, and this BVA President Robin Hargreaves presents Fiona Godlee, had the potential to put patients at risk. Editor-in-Chief of the BMJ, with the Wooldridge medal after Traditionally, randomised clinical her plenary lecture on November 21 trials had been considered to be at the apex of the evidence pyramid, a hierarchy of of influenza infection. During the H1N1 types of clinical evidence which began with influenza pandemic of 2009, governments anecdote and expert opinion at the bottom worldwide began to stockpile Tamiflu on and peaked with the most scientifically the basis of World Health Organization rigorous types of study, such as double(WHO) guidelines. Later that year, however, blinded, randomised, controlled trials and questions were raised about the evidencesystematic reviews. Dr Godlee suggested base behind Tamiflu and the fact that the that, in light of recent scandals involving 2003 meta-analysis on which the WHO biased and poorly reported studies, this guidelines were partially based had used structure should be questioned, and that unpublished data from the manufacturer, clinical trials that were not only randomised Roche. When the Cochrane Collaboration, and blinded, but also well-reported, an independent organisation that promotes independently conducted and which made evidence-based medicine, re-analysed the their data widely available should now be data on Tamiflu while excluding the studies considered as the peak of the pyramid. for which the data were held by Roche, But what was wrong with the it found no evidence that the drug was evidence now used to inform practice? She effective. Following a lengthy campaign by highlighted the widespread problem of the BMJ and Channel 4, Roche had made publication bias, which resulted in studies some of its data available to the Cochrane with positive findings being over-represented Collaboration, and this was currently being in the published literature. ‘We know analysed, she said. that positive studies are more likely to be This case, argued Dr Godlee, clearly published, to be published faster, published in illustrated that the data behind published higher impact journals and more often cited, clinical trials should be made freely available so that at every stage in the literature we see so that they could be scrutinised by the this positive “optimism bias”,’ she explained. scientific community. She gave several This caused the evidence base to become other examples of cases where ineffective, skewed and could sometimes result in or, in some cases, even harmful, drugs had ineffective treatments being given to patients. been given to patients on the basis of biased Another problem was the lack of results that were not freely available. transparency inherent in many published She noted that the proper reporting of clinical trials – in particular those funded trials was important but also that getting and undertaken by pharmaceutical them published in the first place was another companies. Dr Godlee highlighted the hurdle to overcome. Citing a study of trials case of Tamiflu (oseltamivir), an antiviral funded by the National Institute of Health drug licensed to prevent or slow the spread in the USA, which showed that only 46 per 540 | Veterinary Record | December 7, 2013
cent of trials were published in peerreviewed journals within 30 months of completion (despite legislation to encourage early reporting), Dr Godlee highlighted the fact that there was often a long delay before completed trials were brought into the public domain and that many were never published at all. Finally, she posed the question, ‘How can we make the under-reporting of clinical trial results, both industryand non-industry-funded, a matter of urgent public interest?’ She noted that the BMJ was a major supporter of the All Trials campaign, which calls for all clinical trials, both past and present, to be registered and reported. The BMJ had changed its policy so that it would now only accept clinical trials for publication if the authors were willing to share their anonymised individual patient data on reasonable request. Following her lecture, Dr Godlee took questions from the audience. These related to the efficacy of peer review as a mode of judging scientific papers, the extent to which pharmaceutical companies might withhold clinical data and, given financial pressures, whether the current business model for scientific publishing allowed journals to be truly independent. Former BVA President Peter Harlech Jones asked whether Dr Godlee thought that there was a problem with drug regulation agencies in the UK being partly funded by the pharmaceutical industry and whether this was likely to impact on the extent of their independence. She responded that, while there were problems with independence and transparency in the field of drug regulation, things were changing. The European Medicines Agency (EMA), in particular, had undergone ‘an amazing change in tone and culture’ in the past couple of years, and had ‘put themselves on the front line in saying that they will make available all information that they have’. However, she also said that elements of the pharmaceutical industry were unhappy about this and some organisations were currently suing the EMA. Summarising, she said, ‘I wouldn’t be so worried about the funding mechanism if [regulatory] organisations were more transparent.’ doi: 10.1136/vr.f7170
Downloaded from http://veterinaryrecord.bmj.com/ on June 23, 2015 - Published by group.bmj.com
Evidence-based medicine: can we trust the evidence? Veterinary Record 2013 173: 540
doi: 10.1136/vr.f7170 Updated information and services can be found at: http://veterinaryrecord.bmj.com/content/173/22/540
These include:
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To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
News & Reports bva congress
Evidence-based medicine: can we trust the evidence? More and more nowadays vets are being encouraged to apply evidence-based medicine. But can the results of research be taken at face value? Giving the plenary Wooldridge memorial lecture at this year’s BVA Congress, Fiona Godlee, Editor-in-Chief of the BMJ, discussed why – and how – the results of medical studies should be questioned. How good is the evidence that we base our evidence-based practice on, and to what extent can we trust it? These were questions posed by Fiona Godlee, Editorin-Chief of the BMJ, as she delivered the Wooldridge memorial lecture at this year’s BVA Congress during the London Vet Show on November 21. While there had been a positive shift over recent years – in both veterinary and human medicine – toward choosing treatments whose efficacy had been scientifically proven, the underlying data and methodologies of these studies might be flawed, argued Dr Godlee, and this BVA President Robin Hargreaves presents Fiona Godlee, had the potential to put patients at risk. Editor-in-Chief of the BMJ, with the Wooldridge medal after Traditionally, randomised clinical her plenary lecture on November 21 trials had been considered to be at the apex of the evidence pyramid, a hierarchy of of influenza infection. During the H1N1 types of clinical evidence which began with influenza pandemic of 2009, governments anecdote and expert opinion at the bottom worldwide began to stockpile Tamiflu on and peaked with the most scientifically the basis of World Health Organization rigorous types of study, such as double(WHO) guidelines. Later that year, however, blinded, randomised, controlled trials and questions were raised about the evidencesystematic reviews. Dr Godlee suggested base behind Tamiflu and the fact that the that, in light of recent scandals involving 2003 meta-analysis on which the WHO biased and poorly reported studies, this guidelines were partially based had used structure should be questioned, and that unpublished data from the manufacturer, clinical trials that were not only randomised Roche. When the Cochrane Collaboration, and blinded, but also well-reported, an independent organisation that promotes independently conducted and which made evidence-based medicine, re-analysed the their data widely available should now be data on Tamiflu while excluding the studies considered as the peak of the pyramid. for which the data were held by Roche, But what was wrong with the it found no evidence that the drug was evidence now used to inform practice? She effective. Following a lengthy campaign by highlighted the widespread problem of the BMJ and Channel 4, Roche had made publication bias, which resulted in studies some of its data available to the Cochrane with positive findings being over-represented Collaboration, and this was currently being in the published literature. ‘We know analysed, she said. that positive studies are more likely to be This case, argued Dr Godlee, clearly published, to be published faster, published in illustrated that the data behind published higher impact journals and more often cited, clinical trials should be made freely available so that at every stage in the literature we see so that they could be scrutinised by the this positive “optimism bias”,’ she explained. scientific community. She gave several This caused the evidence base to become other examples of cases where ineffective, skewed and could sometimes result in or, in some cases, even harmful, drugs had ineffective treatments being given to patients. been given to patients on the basis of biased Another problem was the lack of results that were not freely available. transparency inherent in many published She noted that the proper reporting of clinical trials – in particular those funded trials was important but also that getting and undertaken by pharmaceutical them published in the first place was another companies. Dr Godlee highlighted the hurdle to overcome. Citing a study of trials case of Tamiflu (oseltamivir), an antiviral funded by the National Institute of Health drug licensed to prevent or slow the spread in the USA, which showed that only 46 per 540 | Veterinary Record | December 7, 2013
cent of trials were published in peerreviewed journals within 30 months of completion (despite legislation to encourage early reporting), Dr Godlee highlighted the fact that there was often a long delay before completed trials were brought into the public domain and that many were never published at all. Finally, she posed the question, ‘How can we make the under-reporting of clinical trial results, both industryand non-industry-funded, a matter of urgent public interest?’ She noted that the BMJ was a major supporter of the All Trials campaign, which calls for all clinical trials, both past and present, to be registered and reported. The BMJ had changed its policy so that it would now only accept clinical trials for publication if the authors were willing to share their anonymised individual patient data on reasonable request. Following her lecture, Dr Godlee took questions from the audience. These related to the efficacy of peer review as a mode of judging scientific papers, the extent to which pharmaceutical companies might withhold clinical data and, given financial pressures, whether the current business model for scientific publishing allowed journals to be truly independent. Former BVA President Peter Harlech Jones asked whether Dr Godlee thought that there was a problem with drug regulation agencies in the UK being partly funded by the pharmaceutical industry and whether this was likely to impact on the extent of their independence. She responded that, while there were problems with independence and transparency in the field of drug regulation, things were changing. The European Medicines Agency (EMA), in particular, had undergone ‘an amazing change in tone and culture’ in the past couple of years, and had ‘put themselves on the front line in saying that they will make available all information that they have’. However, she also said that elements of the pharmaceutical industry were unhappy about this and some organisations were currently suing the EMA. Summarising, she said, ‘I wouldn’t be so worried about the funding mechanism if [regulatory] organisations were more transparent.’ doi: 10.1136/vr.f7170
Downloaded from http://veterinaryrecord.bmj.com/ on June 23, 2015 - Published by group.bmj.com
Evidence-based medicine: can we trust the evidence? Veterinary Record 2013 173: 540
doi: 10.1136/vr.f7170 Updated information and services can be found at: http://veterinaryrecord.bmj.com/content/173/22/540
These include:
Email alerting service
Receive free email alerts when new articles cite this article. Sign up in the box at the top right corner of the online article.
Notes
To request permissions go to: http://group.bmj.com/group/rights-licensing/permissions To order reprints go to: http://journals.bmj.com/cgi/reprintform To subscribe to BMJ go to: http://group.bmj.com/subscribe/
