What is a clinician to make of the “evidence”? Its good for Tweets. You must go with your experience.

February 17, 2011
By

 

bI am sorry if I keep promoting Twitter to readers but I am fascinated the amount of information I get exposed to. I have considered  following only people who confirm to my prejudices in order wake up feeling really good about myself, however I try to follow a broad range of views relevant to things that interest me. In sport I go exclusively with Arsenal however in health care I try to view all sides and when I see something interesting I look deeper than the 140 characters.

Yesterday I was drawn to an interesting study (below) which came to the conclusion that painkillers acted like a placebo. The conclusion is hardly surprising to practitioners who do not prescribe drugs to patients. Skeptic Professor David Colquhoun takes a different view of the study and tweeted a view from “Majikthyse” who disagreed with the conclusion of George Lewith.

As someone who has experienced the agony of Gout I would not describe Declofenac as a placebo, however neither do I believe people with dysfunction/subluxation in their spinal joints need it either. All this information is great for twitter, but I can not say it makes me a great deal wiser in dealing with patients. That comes from experience, practicing chiropractic and developing a really good technique by adjusting spinal joints every day. So its hardly surprising then when Edzard Ernst announce he is frustrated with  people making claims from research.

Professor Ernst  announced today that he has felt an “increasingly strong sensation of frustration"and has “grown less and less tolerant with people who clearly promote nonsense”. Yesterday he had a pop at Yoga as he tries to bring more disciplines into CAM . I asked him if sexual activity might come under his jurisdiction as I am not aware of any scientific evidence supporting the benefits of masturbation. People take what they want out of research and if you have a science degree you can pick holes in a methodology. In one of the examples below you have a PhD picking holes in a Cochrane review.

To those who believe our future is in producing more and more evidence, to please Ernst et al I say forget it. There is no question that there are physiological benefits to maintaining spinal joint function. I am happy for researchers to go out and specify what the specific benefits of spinal care are, however I dont believe what I do will ever amount to a specific cure for anything or anybody. Its quiet simply about maintaining joint function; KISS and you either see that as a good idea or you dont.

Knowledge is knowing a tomato is a fruit, wisdom is not putting it in a fruit salad.

 

Negative experiences can stop painkillers working
By James GallagherHealth reporter, BBC News

A patient’s belief that a drug will not work can become a self fulfilling prophecy, according to researchers.

They showed the benefits of painkillers could be boosted or completely wiped out by manipulating expectations.

The study, published in Science Translational Medicine, also identifies the regions of the brain which are affected.

Experts said this could have important consequences for patient care and for testing new drugs.

Heat was applied to the legs of 22 patients, who were asked to report the level of pain on a scale of one to 100. They were also attached to an intravenous drip so drugs could be administered secretly.

The initial average pain rating was 66. Patients were then given a potent painkiller, remifentanil, without their knowledge and the pain score went down to 55.

They were then told they were being given a painkiller and the score went down to 39.

Then, without changing the dose, the patients were then told the painkiller had been withdrawn and to expect pain, and the score went up to 64.

So even though the patients were being given remifentanil, they were reporting the same level of pain as when they were getting no drugs at all.

Professor Irene Tracey, from Oxford University, told the BBC: "It’s phenomenal, it’s really cool. It’s one of the best analgesics we have and the brain’s influence can either vastly increase its effect, or completely remove it."

The study was conducted on healthy people who were subjected to pain for a short period of time. She said people with chronic conditions who had unsuccessfully tried many drugs for many years would have built up a much greater negative experience, which could impact on their future healthcare.

Professor Tracey said: "Doctors need more time for consultation and to investigate the cognitive side of illness, the focus is on physiology not the mind, which can be a real roadblock to treatment."

Brain scans during the experiment also showed which regions of the brain were affected.

The expectation of positive treatment was associated with activity in the cingulo-frontal and subcortical brain areas while the negative expectation led to increased activity in the hippocampus and the medial frontal cortex.

Researchers also say the study raises concerns about clinical trials used to determine the effectiveness of drugs.

George Lewith, professor of health research at the University of Southampton, said: "It’s another piece of evidence that we get what we expect in life.

"It completely blows cold randomised clinical trials, which don’t take into account expectation."

 

The wrong end of the stick

Posted on 17 February, 2011 by majikthyse

An interesting paper in Science Translational Medicine reports that responses to treatment of induced pain with an opiate analgesic are heavily influenced by expectation. Briefly, if volunteers were told that they were getting the opiate,  their pain relief scores were twice as high as when they were told it was placebo. This was corroborated by brain imaging data. Should we be surprised? I am not. It’s a quite elegant study, but we have known for decades that pain above all else is heavily influenced by expectation. The problem lies in the way it was reported. The full paper is sadly behind a paywall, but this is so common that abstracts have assumed more prominence than they deserve. At the end of their abstract, the authors say:

On the basis of subjective and objective evidence, we contend that an individual’s expectation of a drug’s effect critically influences its therapeutic efficacy and that regulatory brain mechanisms differ as a function of expectancy.

Their use of the generic term “a drug’s effect” is unfortunate. It implies that this applies to all drugs, when it only applies to analgesics on the basis of these data. This over-generalisation was of course carried forward by the BBC’s report, for which this link label was used:

Pessimism ‘stops drugs working’

In an age of dumbing down, this was one of the dumbest I have seen

Rest of the article

Yesterday a Cochrane Review was promoting Zinc Supplements for a cold. Today others are disagreeing with Cochrane who we are told is the Gold Standard of evidence. The fact is all this will be out of Date ten years from now and no one will care.

This is Carl Heneghan view of the Cochrane review Last edited 17th February 2011

There’s no cure for the common cold, but according to a Cochrane Reviews, using zinc supplements may shorten the illness by a few days.

I can see all the hypochondriacs out there, start throwing away there vitamin C. The vitamin for staving off the cold, thanks to Linus Pauling, who said he’d never had a cold in his life. Well, you’ve been wasting your time, because now there is zinc. Wonderful, but is it any good.

Should we just take the fact a Cochrane review is gospel and get on with sucking the pastels? Just because a reputable journal publishes a paper it doesn’t mean the findings will stand up to scrutiny. Reading the news won’t help because there isn’t one critical analysis out there.

What the Cochrane review of Zinc for the common cold found from 13 trials was that the intake of zinc is associated with a significant reduction in the duration and severity of common cold symptoms. What concerns me about the result is the amount of heterogeneity for the main outcome, I squared of 93%.

At this amount of heterogeneity, which is the studies results differ so much, it is implausible to combine them. Generally anymore than 50% heterogeneity you shouldn’t combine outcomes unless you have a good reason why it makes sense. They don’t. The studies differed in terms of variable formulations (zinc gluconate or acetate lozenges, zinc sulphate syrup) and dose range (30 to 160 mg/day) as well as mean duration of symptoms prior to administration of zinc (varying from 24 to 48 hours).

The worst of it is, in the authors limitations they state ‘the results from all the trials may not be comparable’. Couldn’t agree more.

This review also has the added problem of multiple comparisons. Reporting day 3 and 5 results are not significant, and hey presto at day 7 there was a significant difference between the zinc and control group at a p value of 0.05, doesn’t wash. For those of you who have no idea what I’m on about visit thebonferonni correction.

Oh and by the way, eleven of the studies were funded by pharmaceutical companies. And I didn’t even get the chance to say most trials relied on community-acquired infections in which the infecting agent was not identified. This is what the author say ‘so it is unclear whether zinc helps those with rhinoviral cold or even cold due to other viruses.’ And one last moan, ‘given its toxicological profile, the potential for zinc to induce adverse effects at the doses participants are required to take also needs to be determined’.

Want my advice, keep taking the vitamin C, it tastes better.

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  • Fedup

     New study on homeopathy from the swiss out soon.

    http://www.nationalcenterforhomeopathy.org/content/homeopathy-is-effective-according-to-swiss-federal-report

    Like this quote from them.

    “Interestingly, the HTA methodology, unlike meta-analyses and systematic reports such as the Cochrane Collaboration, does not just ask the question of effectiveness of a particular intervention, it also addresses the questions of effectiveness of a therapy in everyday use (i.e. real world effectiveness), how it is used, its safety and its cost-effectiveness”

    Real world!! get it EE.

  • Stefaan

    Evolution is fact. Sorry but I had to.

  • Fedup

    This is a bit off subject but I think this guys sort of hits the nail on the head. Good read.
    http://wherewithal1.wordpress.com/2010/03/25/on-fact-faith-and-truth/

    “The smartest human being I have ever met (and believe me, children – she’s really fucking smart) once explained it to me this way: The universe is an enormous place full of stuff we don’t know. Somewhere in that immensity, we live inside miniscule bubbles made up of our knowledge. When we learn new things, the size of our bubble expands, but the net result of this is that the surface area of our bubble (the interface where our knowledge meets our ignorance) increases. Therefore, expanding our knowledge exponentially increases our awareness of just how much we don’t know.
    This is why those who posses truly superior intellects are usually not prideful about it. Real intelligence instills humility. Real intelligence knows that it has arrived where it is through a certain amount of luck and is thankful for it. And real intelligence knows what it is – it needs no validation. This is why most people who are truly intelligent view their intelligence as just another physical attribute, like being tall or having blue eyes.
    And then there are those who just think they’re smart. Those who are, in fact, not smart at all, but they believe otherwise because some test or web site or TV show told them otherwise. To be fair, they probably clock in at the smarter end of mediocrity, but they don’t actually ever cross over into the realm of intelligence. And stupidity that thinks it’s smart is the most dangerous form of stupidity.
    You know the type – there’s no humility in this crowd. They’re oblivious to the vastness of their ignorance, mainly because they never look up from the shiny baubles of their amassed ‘knowledge’. They actually believe that they ‘know’ things. They speak of ‘truth’ and ‘fact’ that is ‘proven’ and ‘undeniable’ as if such things actually exist. And what really drives them crazy is when someone has the gall to question their so-called ‘knowledge’. This is when they leap to the attack, and their attack always takes the same form: they must prove you wrong. This is the only manner in which they can believe themselves to be right. The fastest – hell, the only – route to intellectual superiority lies in the ability to point to another human being and convincingly declare: You are wrong! It’s kind of sad, actually.
    But here’s the thing that pisses off the genius wannabees the most: that it is unacceptable in our society to walk up to others and say “I’m really smart”. I mean, what’s the point of possessing a superior intellect if nobody notices? How will everyone else know they are inferior unless their betters point it out to them?
    So the wannabees found themselves in a bit of a pickle. How can they show off their intellectual superiority without just coming out and saying it?
    After applying their mediocre intellects to the matter, they eventually decided that the way to show off their brains was to be annoying. You know – needlessly correcting grammar. Obsessing on minute, meaningless detail. Memorizing acronyms and using the complete term instead. You’ve been exposed to the behavior. You’ve probably wanted to knee a groin over it.
    Eventually, though, they managed to see through the fog of their mediocrity and noticed that all they were accomplishing was to piss everyone off. While they may have been exhibiting their superiority, the inferior masses were clearly not ‘getting it’. A new method was called for, and after much screaming and gnashing of teeth, one member of this ‘intelligentsia’ stood up and said “Um…what about this ‘God’ thing?”
    After a brief fight, he managed to clear enough space around himself to offer an explanation: “I meant that we should profess ourselves as atheists. Everyone knows religion is for idiots. If we say we don’t believe in God, everyone will know we’re smart. And society allows us to go around saying we’re atheists.”
    The rest – as they say – is history. Now the creme de la mediocre have adopted atheism as their own personal religion. And they cling to a few studies that support their primary idiocy, i.e., ‘smart people tend to be atheists’.
    But what the mediocre minds really hate most is me. I show up and declare my atheism in complete (usually well-constructed) sentences, and they welcome me with open arms.
    And then I go and ruin everything by explaining a few things to them. Like evolution is a belief, not a fact. Like unbelief is as much a matter of faith as belief. Like atheism is, in fact, a form of religion, as is science. And my personal favorite, the one they hate most:
    The universe is a really big place. There’s enough room in it for more than one Truth.”

  • Fedup

    “What happens after a retraction for falsified data? An example from Endocrinology
    with 2 comments

    In the world of scientific misconduct, it’s often worth keeping track of what happens to scientists whose papers were retracted because of falsified or otherwise fraudulent results.”

  • http://www.chiropracticlive.com Richard Lanigan

    To be honest we should not worry to much about what the skeptics think. Its why the representatives of the profession want to go down this path is what concerns me

  • Fedup

    “Exclusive: Researcher found guilty of misconduct at UCL had been dismissed from Cambridge for data fabrication”

    .”Update on mysterious JACI retraction: Data were falsified”

    I think we may have uncovered a hornets nest!!!!

  • Fedup

    Richeard have you seen this site could be very interesting with your fight against EVIDENCE only skeptics.

    http://retractionwatch.wordpress.com/

  • Fedup

    “Millions of NHS patients may be at risk after being treated with drugs based on “fraudulent research” by a world-renowned anaesthetist.

    Joachim Boldt, 57, is at the centre of a criminal investigation after being accused of forging up to 90 influential studies on fluid drugs called colloids, used to boost blood volume in patients having surgery.

    He has now been stripped of his professorship and sacked from a German hospital. Over a decade he has published papers advocating colloids, contradicting other studies highlighting their risks which include kidney or heart failure and severe loss of blood – all of which could lead to death in surgery.”

    If the so called skeptics were so concerned over public health and welfare why are they not screaming blue murder over this?. Could it be that stories like this show their whole understanding on subjects, that they know nothing about but report to be expert on because they can point to research, is totally flawed and can be fabricated at any stage? Bit like what EE does?

    http://www.thisislondon.co.uk/standard/article-23928844-fears-for-millions-of-nhs-patients-over-drug-fraud.do

  • Fedup

    research is so thorough, skeptics base all their so called knowledge on research published in journals. Ernst has to be right because he researchers all forms of CAM and couldn,t possibly have any bias.LOL

    “A prominent Massachusetts anesthesiologist allegedly fabricated 21 medical studies that claimed to show benefits from painkillers like Vioxx and Celebrex, according to the hospital where he worked.

    Baystate Medical Center, Springfield, Mass., said that its former chief of acute pain, Scott S. Reuben, had faked data used in the studies, which were published in several anesthesiology journals between 1996 and 2008.

    Associated Press
    The anesthesiologist allegedly faked data in 21 studies on the use of various painkillers, including Vioxx.
    .The hospital has asked the medical journals to retract the 21 studies,”

    “Reuben was considered a prolific and influential researcher in pain management, and his purported findings altered the way millions of patients are treated for pain during and after orthopedic surgeries.[1] Reuben has now admitted that he never conducted any of the clinical trials on which his conclusions were based “in what may be considered the longest-running and widest-ranging cases of academic fraud.”[

  • http://www.chiropracticlive.com Richard Lanigan

    THe skeptics know this for them CAM is homeopathy and should be evaluated like a drug and everyone is a quack. Its like talking to the wall so set are they in their views of CAM.

    If you want to tweet your comment, you click the “Share on” button on bottom left of Text box (turns blue) before you click “post as..” and a link should appear on your twitter

  • Fedup

    “The advantage of randomized trials is well known; they offer a powerful means to evaluate the efficacy of procedures in that comparison groups are equally constituted with respect to known and unknown predictors of outcome. As such, these trials offer an unbiased assessment of the impact of a procedure. So why are such trials not more prevalent in surgery? We believe that such trials can be more difficult to design and conduct for surgical procedures than for new pharmaceutical agents. Moreover, because surgical innovation is characterized by a high degree of incremental change and heavy dependence on technical skill and experience, statistical inference from trial data is often more challenging.”

    “heavy dependence on technical skill and experience, ” the key point really.

  • Fedup

    Tried to twitter this but to long.

    “Given the evidence that surgical experience can impact outcomes, one source of variability that may need to be controlled for in surgical trials, especially RCTs, is surgeons’ diverse experience with a given procedure. A surgeon may not routinely do a procedure because it is not his/her preferred procedure for a given condition or because his/her patient volume for that particular condition is such that he/she rarely needs to do the procedure.”

    http://www.medscape.com/viewarticle/579200_4

  • http://www.chiropracticlive.com Richard Lanigan

    Another view of this was posted today by Andy Lewis of Quackometer well actually its not a different view its another mention of the “Majikthyse” posting on this study. I supose it beats referring to Edzrd Ernst all the time. For skeptics its amazing how predictable their comments are.

    Anyway below is what Andy has to say on the pain study. What is particularly interesting is what Andy has to say about regulation of CAM. In fact David Calquhoun explained to Andy today how one evaluates a “regulator of quackery”. Perhaps the GCC will put Andys blog on their website as a glowing endorsement.

    Andy states; “This is absurd nonsense. As the blogger Majikthyse says on his blog,

    Is not this study a “cold randomised clinical trial” its very self? This from a professor who is employed to run “cold randomised clinical trials”. To claim that one randomised controlled trial (RCT) in a single therapeutic area invalidates the entire discipline of clinical trials is bizarre and not remotely supported by the evidence. But this study simply doesn’t mitigate in the slightest way against RCTs, because it is an RCT. Sorry, but in case Lewith is reading this I have to make it crystal clear.

    It looks a lot like bandwagon jumping to me. Quite.

    The new College of Medicine, the quackery promoting organisation that has arisen from the ashes of fraud of Prince Charles Foundation for Integrated Health is also very keen to muddy the water around medical evidence. The College intends to ‘commission a full-scale review on the nature of knowledge for clinical practice”. Given the objectives of the FIH and the people involved, there can be little doubt that this review will help undermine the very concepts of evidence that enable us to make informed choices about treatments and in doing so, let in all forms of quackery through the back door.

    So, to answer my question I set in the title: how do we spot bad regulation of alternative medicine. Well, let me suggest the Quackometer rule of thumb on the issue. A basic tenet of regulating quackery: if the quacks are happy with the proposed regulation, then it will not be effective regulation capable of protecting the public from misleading claims, ineffective treatments and dangerous beliefs.

    Any regulatory regime that is acceptable to the mode of thinking found in alt med must somehow avoid the obvious issue of answering the most critical question of how we know if the treatment works or not. Ineffective treatments are inherently harmful. Regulating ineffective pseudo-medical treatments gives false choices to patients and disenfranchises them from having appropriate informed consent about what is right form them. Such statutory regulation then becomes simply a matter of providing trade protectionism – state sanctioned statutory cartels of superstitious medical practices.

    The regulatory cartels allow the quacks to create monopolies of control over what they do, protect themselves from external regulatory forces, such as Trading Standards, increase their status to that of other real health care providers and compete for the same public funds on an equal footing to meaningful and evidenced treatments.

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