On 2017 Nov 27, Harri Hemila commented:

Djulbegovic and Guyatt do not refute my criticism of their 3 novel EBM principles

Djulbegovic and Guyatt challenge my short critique of Djulbegovic B, 2017 by stating that “the BMJ’s rating of EBM as one of medicine’s 15 most important advances since 1840 is but one testimony to the impact of its conceptualization of key principles of medical practice, see BMJ 2007 Jan 20;334(7585):111”.

The short news article to which they refer to has the title “BMJ readers choose the sanitary revolution as greatest medical advance since 1840”.

First, that BMJ news article is a 305-word summary of findings from a Gallup poll of 11341 readers of the BMJ, only one third of whom were physicians. Reporting the opinions of BMJ readers does not refute my criticisms.

Second, the 305-word BMJ text was published in 2007. The BMJ readers could not have anticipated in 2007 the revision of the basic principles of EBM a decade later by Djulbegovic B, 2017. The findings in a 10-year-old survey are not relevant to the current discussion of whether the 3 novel EBM principles are reasonable.

Third, the short BMJ text does not mention the term EBM anywhere in the piece. The text states that “sanitation topped the poll, followed closely by the discovery of antibiotics and the development of anaesthesia.” There are no references to EBM whatsoever.

Fourth, one major proposal of the original EBM-paper in JAMA (1992) was that physicians should not lean uncritically on authorities: “the new [EBM] paradigm puts a much lower value on authority”, see p. 2421 in Evidence-Based Medicine Working Group., 1992. Thus, it is very odd that Djulbegovic and Guyatt argue for the importance of the EBM-approach, while they simultaneously consider that the BMJ is such an important authority. It is especially surprising that the mere reference to a 305-word text in the BMJ somehow would refute my comments, even though the text does not discuss EBM or other issues related to my comments either literally or by implication.

Fifth, Djulbegovic and Guyatt state that the 305-word text in the BMJ is a “testimony” in favor of EBM. Testimonies do not seem relevant to this kind of academic discussion. Testimonies are popularly used when trying to impress uncritical readers about claims to which there is no sound support, such as testimonies for homeopathy on numerous pages in the internet.

Djulbegovic and Guyatt also write “The extent to which EBM ideas are novel or, rather, an extension, packaging and innovative presentation of antecedents, is a matter we find of little moment.”

I do not agree with their view. If there is no novelty in the 3 new EBM principles proposed by Djulbegovic B, 2017, and if there is no reasonable demarcation line between “evidence-based medicine” and “ordinary medicine” or simply “medicine”, why should we reiterate the prefix “evidence-based” instead of simply stating the we are discussing “medicine” and we try to make progress in medicine. If “evidence-based” does not give any added meaning in a discussion, why should such a prefix be used?

Djulbegovic and Guyatt stated that I “do not appear to disagree with [their] overview of the progress in EBM during last quarter of century”. That statement is not entirely correct. A short commentary must have a narrow focus. The focus in my comment was simply on the 3 new EBM principles that were presented by Djulbegovic B, 2017. The absence of any other comments on their overview does not logically mean that I agree with other parts of their overview.

On 2017 Nov 23, BENJAMIN DJULBEGOVIC commented:

Hemila does not appear to disagree with our overview of the progress in EBM during last quarter of century. His main concerns seem to relate to the origin of the ideas. The extent to which EBM ideas are novel or, rather, an extension, packaging and innovative presentation of antecedents, is a matter we find of little moment. The BMJ’s rating of EBM as one of medicine’s 15 most important advances since 1840 is but one testimony to the impact of its conceptualization of key principles of medical practice (see BMJ. 2007 Jan 20; 334(7585): 111.doi: 10.1136/bmj.39097.611806.DB)

Benjamin Djulbegovic & Gordon Guyatt

On 2017 Nov 19, Harri Hemila commented:

The three novel principles for EBM are old: the emperor has no clothes

In their paper, Djulbegovic B, 2017 describe three novel principles for EBM.

Djulbegovic and Guyatt write (p. 416): “the first EBM epistemological principle is that not all evidence is created equal, and that the practice of medicine should be based on the best available evidence.”

There is no novelty in that statement. Even before 1992 scientists including those in the medical fields, understood that some types of research give more reliable answers.

Furthermore, Djulbegovic and Guyatt do not follow the first principle in their own paper. They write (p. 416): “Millions of healthy women were prescribed hormone replacement therapy [HRT] on the basis of hypothesised reduction in cardiovascular risk; randomised trials refuted these benefits and demonstrated that hormone replacement therapy increased the incidence of breast cancer.”

In an earlier paper, Vandenbroucke JP, 2009 wrote “Recent reanalyses have brought the results from observational and randomised studies into line. The results are surprising. Neither design held superior truth. The reasons for the discrepancies were rooted in the timing of HRT and not in differences in study design.” In another paper, Vandenbroucke JP, 2011 wrote “Four meta-analyses contrasting RCTs and observational studies of treatment found no large systematic differences … the notion that RCTs are superior and observational studies untrustworthy … rests on theory and singular events”.

Djulbegovic and Guyatt thus reiterate old assumptions about the unambiguous superiority of RCTs compared with observational studies. They do not follow their own first EBM principle that arguments ”should be based on the best available evidence”. The above mentioned Vandenbroucke’s papers had already been published and were therefore available; thus they should have been taken into account when Djulbegovic and Guyatt argued for the superiority of RCTs in 2017.

Djulbegovic and Guyatt further write (p. 416): “the second [EBM] principle endorses the philosophical view that the pursuit of truth is best accomplished by evaluating the totality of the evidence, and not selecting evidence that favours a particular claim.”

There is no novelty in espousing that principle either. Objectivity has been a long term goal in the natural sciences, and also in the medical fields.

Furthermore, Djulbegovic and Guyatt do not follow the second principle in their own paper. Their reference 94 is to the paper by Lau J, 1992, to which Djulbegovic ja Guyatt refer with the following statement (p. 420): “the history of a decade-or-more delays in implementing interventions, such as thrombolytic therapy for myocardial infarction.” However, in the same paper, Lau J, 1992 also calculated that there was very strong evidence that magnesium was a useful treatment for infarctions with an OR = 0.44 (95% CI: 0.27 - 0.71). However, in the ISIS-4 trial, magnesium had no effects: “Lessons from an effective, safe, simple intervention that wasn't ”, see Egger M, 1995.

Thus, Djulbegovic and Guyatt cherry picked one intervention (trombolytic therapy) to support their statement that many interventions should have been taken into use much more rapidly, but they dismissed another intervention in the paper by Lau J, 1992, that would serve as an unequivocal counter example of the same statement. This surely is an example of “selecting evidence that favours a particular claim”.

Principles 1 ja 2 had already been advocated in James Lind’s book on scurvy (1753), which was listed as reference number 1 in Djulbegovic B, 2017. Lind wrote: “As it is no easy matter to root out old prejudices, or to overturn opinions which have acquired an establishment by time, custom and great authorities; it became therefore requisite for this purpose, to exhibit a full and impartial view of what has hitherto been published on the scurvy; and that in a chronological order, by which the sources of those mistakes may be detected. Indeed, before this subject could be set in a clear and proper light, it was necessary to remove a great deal of rubbish.” See Milne I, 2012.

Thus, Djulbegovic ja Guyatt’s EBM principles 1 and 2 are not new; they are at least over 250 years old.

Djulbegovic and Guyatt write further (p. 416): “the third epistemological principle of EBM is that clinical decision making requires consideration of patients’ values and preferences.”

The importance of patient autonomy is not an innovation that is attributal to EBM, however.

When the EBM-movement started with the publication of the JAMA (1992) paper by the Evidence-Based Medicine Working Group., 1992, there was novelty in the proposals. The suggestion that each physician should himself or herself read original literature to the extent proposed by EBM enthusiasts in 1992 was novel as far as I can comprehend from the history. The strength of the suggestion to restrict to RCTs as the source of valid evidence about the efficacy of medical interventions was also novel as far as I can see. Thus, the Evidence-Based Medicine Working Group., 1992 had novel ideas and described the background for those ideas. We can disagree about the 1992 proposals  as many have done  but I do not consider that it is fair to claim that the JAMA (1992) paper had no novelty.

In contrast, the aforementioned three principles described by Djulbegovic B, 2017 are not novel. The principles can be traced back to times long before even 1992. In addition, none of the principles alone or in combination set any unambiguous demarkation line as to what EBM is in 2017 and what it is not. How does evidence-based medicine differ from “ordinary” medicine, which has been using the same three principles for ages. If there is no difference between the two, why should the “evidence-based” term be used instead of simply writing “medicine”.

In their paper, Djulbegovic and Guyatt also describe their visions for the future, but I cannot see that any of their visions is specific to EBM. We could as well write their visions for future by changing “EBM” to “medicine”.

On 2017 Nov 19, Harri Hemila commented:

The three novel principles for EBM are old: the emperor has no clothes

In their paper, Djulbegovic B, 2017 describe three novel principles for EBM.

Djulbegovic and Guyatt write (p. 416): “the first EBM epistemological principle is that not all evidence is created equal, and that the practice of medicine should be based on the best available evidence.”

There is no novelty in that statement. Even before 1992 scientists including those in the medical fields, understood that some types of research give more reliable answers.

Furthermore, Djulbegovic and Guyatt do not follow the first principle in their own paper. They write (p. 416): “Millions of healthy women were prescribed hormone replacement therapy [HRT] on the basis of hypothesised reduction in cardiovascular risk; randomised trials refuted these benefits and demonstrated that hormone replacement therapy increased the incidence of breast cancer.”

In an earlier paper, Vandenbroucke JP, 2009 wrote “Recent reanalyses have brought the results from observational and randomised studies into line. The results are surprising. Neither design held superior truth. The reasons for the discrepancies were rooted in the timing of HRT and not in differences in study design.” In another paper, Vandenbroucke JP, 2011 wrote “Four meta-analyses contrasting RCTs and observational studies of treatment found no large systematic differences … the notion that RCTs are superior and observational studies untrustworthy … rests on theory and singular events”.

Djulbegovic and Guyatt thus reiterate old assumptions about the unambiguous superiority of RCTs compared with observational studies. They do not follow their own first EBM principle that arguments ”should be based on the best available evidence”. The above mentioned Vandenbroucke’s papers had already been published and were therefore available; thus they should have been taken into account when Djulbegovic and Guyatt argued for the superiority of RCTs in 2017.

Djulbegovic and Guyatt further write (p. 416): “the second [EBM] principle endorses the philosophical view that the pursuit of truth is best accomplished by evaluating the totality of the evidence, and not selecting evidence that favours a particular claim.”

There is no novelty in espousing that principle either. Objectivity has been a long term goal in the natural sciences, and also in the medical fields.

Furthermore, Djulbegovic and Guyatt do not follow the second principle in their own paper. Their reference 94 is to the paper by Lau J, 1992, to which Djulbegovic ja Guyatt refer with the following statement (p. 420): “the history of a decade-or-more delays in implementing interventions, such as thrombolytic therapy for myocardial infarction.” However, in the same paper, Lau J, 1992 also calculated that there was very strong evidence that magnesium was a useful treatment for infarctions with an OR = 0.44 (95% CI: 0.27 - 0.71). However, in the ISIS-4 trial, magnesium had no effects: “Lessons from an effective, safe, simple intervention that wasn't ”, see Egger M, 1995.

Thus, Djulbegovic and Guyatt cherry picked one intervention (trombolytic therapy) to support their statement that many interventions should have been taken into use much more rapidly, but they dismissed another intervention in the paper by Lau J, 1992, that would serve as an unequivocal counter example of the same statement. This surely is an example of “selecting evidence that favours a particular claim”.

Principles 1 ja 2 had already been advocated in James Lind’s book on scurvy (1753), which was listed as reference number 1 in Djulbegovic B, 2017. Lind wrote: “As it is no easy matter to root out old prejudices, or to overturn opinions which have acquired an establishment by time, custom and great authorities; it became therefore requisite for this purpose, to exhibit a full and impartial view of what has hitherto been published on the scurvy; and that in a chronological order, by which the sources of those mistakes may be detected. Indeed, before this subject could be set in a clear and proper light, it was necessary to remove a great deal of rubbish.” See Milne I, 2012.

Thus, Djulbegovic ja Guyatt’s EBM principles 1 and 2 are not new; they are at least over 250 years old.

Djulbegovic and Guyatt write further (p. 416): “the third epistemological principle of EBM is that clinical decision making requires consideration of patients’ values and preferences.”

The importance of patient autonomy is not an innovation that is attributal to EBM, however.

When the EBM-movement started with the publication of the JAMA (1992) paper by the Evidence-Based Medicine Working Group., 1992, there was novelty in the proposals. The suggestion that each physician should himself or herself read original literature to the extent proposed by EBM enthusiasts in 1992 was novel as far as I can comprehend from the history. The strength of the suggestion to restrict to RCTs as the source of valid evidence about the efficacy of medical interventions was also novel as far as I can see. Thus, the Evidence-Based Medicine Working Group., 1992 had novel ideas and described the background for those ideas. We can disagree about the 1992 proposals  as many have done  but I do not consider that it is fair to claim that the JAMA (1992) paper had no novelty.

In contrast, the aforementioned three principles described by Djulbegovic B, 2017 are not novel. The principles can be traced back to times long before even 1992. In addition, none of the principles alone or in combination set any unambiguous demarkation line as to what EBM is in 2017 and what it is not. How does evidence-based medicine differ from “ordinary” medicine, which has been using the same three principles for ages. If there is no difference between the two, why should the “evidence-based” term be used instead of simply writing “medicine”.

In their paper, Djulbegovic and Guyatt also describe their visions for the future, but I cannot see that any of their visions is specific to EBM. We could as well write their visions for future by changing “EBM” to “medicine”.

On 2017 Nov 23, BENJAMIN DJULBEGOVIC commented:

Hemila does not appear to disagree with our overview of the progress in EBM during last quarter of century. His main concerns seem to relate to the origin of the ideas. The extent to which EBM ideas are novel or, rather, an extension, packaging and innovative presentation of antecedents, is a matter we find of little moment. The BMJ’s rating of EBM as one of medicine’s 15 most important advances since 1840 is but one testimony to the impact of its conceptualization of key principles of medical practice (see BMJ. 2007 Jan 20; 334(7585): 111.doi: 10.1136/bmj.39097.611806.DB)

Benjamin Djulbegovic & Gordon Guyatt

On 2017 Nov 27, Harri Hemila commented:

Djulbegovic and Guyatt do not refute my criticism of their 3 novel EBM principles

Djulbegovic and Guyatt challenge my short critique of Djulbegovic B, 2017 by stating that “the BMJ’s rating of EBM as one of medicine’s 15 most important advances since 1840 is but one testimony to the impact of its conceptualization of key principles of medical practice, see BMJ 2007 Jan 20;334(7585):111”.

The short news article to which they refer to has the title “BMJ readers choose the sanitary revolution as greatest medical advance since 1840”.

First, that BMJ news article is a 305-word summary of findings from a Gallup poll of 11341 readers of the BMJ, only one third of whom were physicians. Reporting the opinions of BMJ readers does not refute my criticisms.

Second, the 305-word BMJ text was published in 2007. The BMJ readers could not have anticipated in 2007 the revision of the basic principles of EBM a decade later by Djulbegovic B, 2017. The findings in a 10-year-old survey are not relevant to the current discussion of whether the 3 novel EBM principles are reasonable.

Third, the short BMJ text does not mention the term EBM anywhere in the piece. The text states that “sanitation topped the poll, followed closely by the discovery of antibiotics and the development of anaesthesia.” There are no references to EBM whatsoever.

Fourth, one major proposal of the original EBM-paper in JAMA (1992) was that physicians should not lean uncritically on authorities: “the new [EBM] paradigm puts a much lower value on authority”, see p. 2421 in Evidence-Based Medicine Working Group., 1992. Thus, it is very odd that Djulbegovic and Guyatt argue for the importance of the EBM-approach, while they simultaneously consider that the BMJ is such an important authority. It is especially surprising that the mere reference to a 305-word text in the BMJ somehow would refute my comments, even though the text does not discuss EBM or other issues related to my comments either literally or by implication.

Fifth, Djulbegovic and Guyatt state that the 305-word text in the BMJ is a “testimony” in favor of EBM. Testimonies do not seem relevant to this kind of academic discussion. Testimonies are popularly used when trying to impress uncritical readers about claims to which there is no sound support, such as testimonies for homeopathy on numerous pages in the internet.

Djulbegovic and Guyatt also write “The extent to which EBM ideas are novel or, rather, an extension, packaging and innovative presentation of antecedents, is a matter we find of little moment.”

I do not agree with their view. If there is no novelty in the 3 new EBM principles proposed by Djulbegovic B, 2017, and if there is no reasonable demarcation line between “evidence-based medicine” and “ordinary medicine” or simply “medicine”, why should we reiterate the prefix “evidence-based” instead of simply stating the we are discussing “medicine” and we try to make progress in medicine. If “evidence-based” does not give any added meaning in a discussion, why should such a prefix be used?

Djulbegovic and Guyatt stated that I “do not appear to disagree with [their] overview of the progress in EBM during last quarter of century”. That statement is not entirely correct. A short commentary must have a narrow focus. The focus in my comment was simply on the 3 new EBM principles that were presented by Djulbegovic B, 2017. The absence of any other comments on their overview does not logically mean that I agree with other parts of their overview.