4 ms·

I'm first in line to criticize unnecessary medicine based on flimsy evidence, but in principle there's nothing wrong with medical reversals. As you begin to co

I'm first in line to criticize unnecessary medicine based on flimsy evidence, but in principle there's nothing wrong with medical reversals. As you begin to collect data about anything, your best guess for the truth will be bouncing around wildly and only slowly settle down as the data accumulates. "Do no harm" is ok as a rule of thumb to counteract the natural tendency for doctors to err on the side of over-medicating (and to account for our expectation that a random intervention is net negative), but it's silly to use as an inflexible principle. If you're so cautious that you never recommend harmful interventions, you're missing out on plenty of interventions that are positive in expectation. Do any of these studies of "medical reversals" attempt to estimate how often reversals should be made ideally?

J-dawg 7y ago
I suppose if you end up reversing an established thing, you'd better have a damn good reason why you were doing that thing in the first place. Why give any treatment that hasn't been through a randomised trial? (Unless, of course, you are giving it as part of a trial)
- the_af 7y ago
  I'm not sure I understand the terminology. If "medical reversal" means -- apologies if I misunderstood -- "stopping a medical treatment which hasn't been shown to be helpful, or one that is not backed by evidence", why is the reversal itself the problem? Shouldn't the focus be on applying treatments backed by robust evidence in the first place, rather than on medical reversals? Of course the two are connected, but the wording seems odd. Medical reversals seem to be a symptom of the problem, not the root cause. Of course, I might be misunderstanding the terminology. edit: I've read the abstract and it seems I am indeed misunderstanding the definition, but for the life of me I cannot understand what "medical reversal" means in layman words.
  - hannob 7y ago
    I think you're not misunderstanding, it's exactly what the term "Medical Reversal" is trying to capture. I.e. of course it's only a symptom, but it's something that can be measured to show there's a problem early on.
  - scott_s 7y ago
    My laymen's definition of medical reversal: a current medical practice that is worse than what we did before.
    - the_af 7y ago
      Ah, thanks! So indeed I was mistaken. I misunderstood it to mean "reverting an unproven/inconclusive treatment" when it actually means "conducting an unproven/inconclusive treatment". I was confused because "reversal" sounds to me as the act of ceasing to do something, i.e. "reverting" the treatment (if you're a programmer: I thought of "reversal" as in "reverting a mistaken commit using git"). I now see it's a technical term which means the opposite! Now it all makes sense.
      - scott_s 7y ago
        Hmm. Sorry, no, that's not my understanding. I think the phenomenon of discovery is distinct from the changing of behavior. I believe it is the discovery itself that is called a "medical reversal." I think the submitted paper defines it in relatively laymen's terms: "Medical reversal occurs when a new clinical trial — superior to predecessors by virtue of better controls, design, size, or endpoints — contradicts current clinical practice." I think an important difference is that current clinical practice is not necessarily thought to be "unproven/inconclusive." Rather, I think people think it has a solid foundation, but better investigation reveals that not to be true.
  - YeGoblynQueenne 7y ago
    I was wondering the same thing. I found this definition: Medical reversal occurs when a new clinical trial — superior to predecessors by virtue of better controls, design, size, or endpoints — contradicts current clinical practice. In recent years, we have witnessed several instances of medical reversal. Famous examples include the class 1C anti-arrhythmics post-myocardial infarction (contradicted by the CAST trial) or routine stenting for stable coronary disease (contradicted by the COURAGE trial). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3238324/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3238324/ The article I link to has one author common with the paper originally posted, way above. Shame that this author seems to have lost the skill of ensuring that terms are propery defined.
- ChrisSD 7y ago
  IMHO, mostly due to history and some caution. A thoroughly oversimplified history would go something like this: In days past a lot of medicine was based on what seems to work or what ought to work. Unless the effect is really obviously disastrous it's easy to believe an intervention is helping even if it's not. Medical research was of course done but doctors mostly went with their gut or whatever article they'd recently read in a journal and liked the sound of. It's only since the late 80's and through the 90's that Evidence Based Medicine really started to get going. Since then doctors have (sometimes slowly) come round to the idea. However all this research takes time. What do you do about those interventions that haven't been tested yet? You could stop doing anything that hasn't been thoroughly researched, but that risks letting people die or suffering unnecessarily.
  - DoreenMichele 7y ago
    It also risks malpractice suits. Over-testing and over-prescribing are rooted in part in doctors trying to cover their own ass and avoid being sued, plus having a good defense in the event they do get sued.
    - AstralStorm 7y ago
      You do know that ineffective practice also risks malpractice suits if it's identified? Even worse if by trying random approaches (face it, an untested experimental medicine is mostly random) you end up harming the patient.
- FPGAhacker 7y ago
  Sometimes the trial itself is an ethical dilemma. Sometimes it's impossible to control because a placebo that effectively mimics side effects of the subject are not feasible.
- jessriedel 7y ago
  Because sometimes we have good reasons to believe something works even without an RCT, and it would be unethical to withhold such treatment. (Not to mention that there is a continuum of RCT quality, so it's unclear what would even count and "proven".) The classic tongue-in-cheek example is parachutes: > Objectives: To determine whether parachutes are effective in preventing major trauma related to gravitational challenge. > Design: Systematic review of randomised controlled trials. > Main outcome measure: Death or major trauma, defined as an injury severity score > 15. > Results: We were unable to identify any randomised controlled trials of parachute intervention. > Conclusions: As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute. https://www.bmj.com/content/327/7429/1459 https://www.bmj.com/content/327/7429/1459
  - pmyteh 7y ago
    This year's Christmas BMJ actually contained an RCT of parachute use when falling out of aeroplanes. It found no effect. It turns out that study design can also be a problem, even with 'gold standard' designs like the RCT... https://www.bmj.com/content/363/bmj.k5094 https://www.bmj.com/content/363/bmj.k5094
  - scott_s 7y ago
    This is why David Gorski and Steven Novella advocate for Science Based Medicine: https://www.painscience.com/articles/ebm-vs-sbm.php https://www.painscience.com/articles/ebm-vs-sbm.php Basically, it advocates incorporating scientific principles into reasoning about medical practices.
najarvg 7y ago
I think you may be missing the larger point the authors are trying to make. It's more nuanced. For every item on a treatment pathway, ask if there is peer reviewed evidence backed by a randomized clinical trial (where possible) to support it. If not, consider doing one. For evidence of harms done by medical reversal, see the other thread as well as consider reading the book "Ending Medical Reversal" by one of the authors Adam Cifu. Also consider following them on twitter if this topic is of interest (Adam Cifu, Vinay Prasad et al).
- the_af 7y ago
  Trying to understand here: is the medical reversal itself which causes harm, or is the harm caused by all the time spent pursuing the wrong treatment before the reversal?
  - DoreenMichele 7y ago
    That will depend on the treatment in question. In some cases, the practice is harmful per se. In other cases, it's not harmful per se, but will prevent a better treatment option from being deployed.
    - AstralStorm 7y ago
      Finally, it might prefer people from supplementing the care with additional practices that are of value due to cost, even when not directly preventing it.
- jessriedel 7y ago
  Your first two sentences aren't supported by the rest of your comment because I'm not rejecting the entire article. (I don't disagree with any of that other stuff you wrote.) I'm just criticizing the implicit assumption that medical reversals are necessarily evidence of a mistake. Indeed, from the second paragraph (emphasis mine): > Medical reversals are a subset of low-value medical practices and are defined as practices that have been found, through randomized controlled trials, to be no better than a prior or lesser standard of care (Prasad et al., 2013; Prasad et al., 2011). That is, the authors assert that something is low value if it is later proven to not work.
caycep 7y ago
To put it in statistics terms, is it more appropriate to look at theses as "reversals" vs. typical Bayesian learning as our understanding of anatomy and pathophysiology improves over time?
- jessriedel 7y ago
  (Assuming you're asking for clarification/confirmation.) Well, some will represent bad/unwise practices, and some will be prudent Bayesian corrections. My prior is that most cases of reversal are the former, but you'd actually have to analyze the past evidence and the decision-making procedure to tell.

J-dawg 7y ago

I suppose if you end up reversing an established thing, you'd better have a damn good reason why you were doing that thing in the first place. Why give any treatment that hasn't been through a randomised trial? (Unless, of course, you are giving it as part of a trial)

the_af 7y ago
I'm not sure I understand the terminology. If "medical reversal" means -- apologies if I misunderstood -- "stopping a medical treatment which hasn't been shown to be helpful, or one that is not backed by evidence", why is the reversal itself the problem? Shouldn't the focus be on applying treatments backed by robust evidence in the first place, rather than on medical reversals? Of course the two are connected, but the wording seems odd. Medical reversals seem to be a symptom of the problem, not the root cause. Of course, I might be misunderstanding the terminology. edit: I've read the abstract and it seems I am indeed misunderstanding the definition, but for the life of me I cannot understand what "medical reversal" means in layman words.
- hannob 7y ago
  I think you're not misunderstanding, it's exactly what the term "Medical Reversal" is trying to capture. I.e. of course it's only a symptom, but it's something that can be measured to show there's a problem early on.
- scott_s 7y ago
  My laymen's definition of medical reversal: a current medical practice that is worse than what we did before.
  - the_af 7y ago
    Ah, thanks! So indeed I was mistaken. I misunderstood it to mean "reverting an unproven/inconclusive treatment" when it actually means "conducting an unproven/inconclusive treatment". I was confused because "reversal" sounds to me as the act of ceasing to do something, i.e. "reverting" the treatment (if you're a programmer: I thought of "reversal" as in "reverting a mistaken commit using git"). I now see it's a technical term which means the opposite! Now it all makes sense.
    - scott_s 7y ago
      Hmm. Sorry, no, that's not my understanding. I think the phenomenon of discovery is distinct from the changing of behavior. I believe it is the discovery itself that is called a "medical reversal." I think the submitted paper defines it in relatively laymen's terms: "Medical reversal occurs when a new clinical trial — superior to predecessors by virtue of better controls, design, size, or endpoints — contradicts current clinical practice." I think an important difference is that current clinical practice is not necessarily thought to be "unproven/inconclusive." Rather, I think people think it has a solid foundation, but better investigation reveals that not to be true.
- YeGoblynQueenne 7y ago
  I was wondering the same thing. I found this definition: Medical reversal occurs when a new clinical trial — superior to predecessors by virtue of better controls, design, size, or endpoints — contradicts current clinical practice. In recent years, we have witnessed several instances of medical reversal. Famous examples include the class 1C anti-arrhythmics post-myocardial infarction (contradicted by the CAST trial) or routine stenting for stable coronary disease (contradicted by the COURAGE trial). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3238324/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3238324/ The article I link to has one author common with the paper originally posted, way above. Shame that this author seems to have lost the skill of ensuring that terms are propery defined.
ChrisSD 7y ago
IMHO, mostly due to history and some caution. A thoroughly oversimplified history would go something like this: In days past a lot of medicine was based on what seems to work or what ought to work. Unless the effect is really obviously disastrous it's easy to believe an intervention is helping even if it's not. Medical research was of course done but doctors mostly went with their gut or whatever article they'd recently read in a journal and liked the sound of. It's only since the late 80's and through the 90's that Evidence Based Medicine really started to get going. Since then doctors have (sometimes slowly) come round to the idea. However all this research takes time. What do you do about those interventions that haven't been tested yet? You could stop doing anything that hasn't been thoroughly researched, but that risks letting people die or suffering unnecessarily.
- DoreenMichele 7y ago
  It also risks malpractice suits. Over-testing and over-prescribing are rooted in part in doctors trying to cover their own ass and avoid being sued, plus having a good defense in the event they do get sued.
  - AstralStorm 7y ago
    You do know that ineffective practice also risks malpractice suits if it's identified? Even worse if by trying random approaches (face it, an untested experimental medicine is mostly random) you end up harming the patient.
FPGAhacker 7y ago
Sometimes the trial itself is an ethical dilemma. Sometimes it's impossible to control because a placebo that effectively mimics side effects of the subject are not feasible.
jessriedel 7y ago
Because sometimes we have good reasons to believe something works even without an RCT, and it would be unethical to withhold such treatment. (Not to mention that there is a continuum of RCT quality, so it's unclear what would even count and "proven".) The classic tongue-in-cheek example is parachutes: > Objectives: To determine whether parachutes are effective in preventing major trauma related to gravitational challenge. > Design: Systematic review of randomised controlled trials. > Main outcome measure: Death or major trauma, defined as an injury severity score > 15. > Results: We were unable to identify any randomised controlled trials of parachute intervention. > Conclusions: As with many interventions intended to prevent ill health, the effectiveness of parachutes has not been subjected to rigorous evaluation by using randomised controlled trials. Advocates of evidence based medicine have criticised the adoption of interventions evaluated by using only observational data. We think that everyone might benefit if the most radical protagonists of evidence based medicine organised and participated in a double blind, randomised, placebo controlled, crossover trial of the parachute. https://www.bmj.com/content/327/7429/1459 https://www.bmj.com/content/327/7429/1459
- pmyteh 7y ago
  This year's Christmas BMJ actually contained an RCT of parachute use when falling out of aeroplanes. It found no effect. It turns out that study design can also be a problem, even with 'gold standard' designs like the RCT... https://www.bmj.com/content/363/bmj.k5094 https://www.bmj.com/content/363/bmj.k5094
- scott_s 7y ago
  This is why David Gorski and Steven Novella advocate for Science Based Medicine: https://www.painscience.com/articles/ebm-vs-sbm.php https://www.painscience.com/articles/ebm-vs-sbm.php Basically, it advocates incorporating scientific principles into reasoning about medical practices.

najarvg 7y ago

I think you may be missing the larger point the authors are trying to make. It's more nuanced. For every item on a treatment pathway, ask if there is peer reviewed evidence backed by a randomized clinical trial (where possible) to support it. If not, consider doing one. For evidence of harms done by medical reversal, see the other thread as well as consider reading the book "Ending Medical Reversal" by one of the authors Adam Cifu. Also consider following them on twitter if this topic is of interest (Adam Cifu, Vinay Prasad et al).

the_af 7y ago
Trying to understand here: is the medical reversal itself which causes harm, or is the harm caused by all the time spent pursuing the wrong treatment before the reversal?
- DoreenMichele 7y ago
  That will depend on the treatment in question. In some cases, the practice is harmful per se. In other cases, it's not harmful per se, but will prevent a better treatment option from being deployed.
  - AstralStorm 7y ago
    Finally, it might prefer people from supplementing the care with additional practices that are of value due to cost, even when not directly preventing it.
jessriedel 7y ago
Your first two sentences aren't supported by the rest of your comment because I'm not rejecting the entire article. (I don't disagree with any of that other stuff you wrote.) I'm just criticizing the implicit assumption that medical reversals are necessarily evidence of a mistake. Indeed, from the second paragraph (emphasis mine): > Medical reversals are a subset of low-value medical practices and are defined as practices that have been found, through randomized controlled trials, to be no better than a prior or lesser standard of care (Prasad et al., 2013; Prasad et al., 2011). That is, the authors assert that something is low value if it is later proven to not work.

caycep 7y ago

To put it in statistics terms, is it more appropriate to look at theses as "reversals" vs. typical Bayesian learning as our understanding of anatomy and pathophysiology improves over time?

jessriedel 7y ago
(Assuming you're asking for clarification/confirmation.) Well, some will represent bad/unwise practices, and some will be prudent Bayesian corrections. My prior is that most cases of reversal are the former, but you'd actually have to analyze the past evidence and the decision-making procedure to tell.