Placebo effect

[Physiotherapist]

No. I don't think the NHS do feel that their funding for the homeopathic hospitals is a vehicle for placebo. The do it because they believe it works.

 

[Dancing David]

Saizai, I have yet to see you produce any research that the placebo effect actualy exists and that it is a substantial effect, as I said before all the studies I have seen would place it within random variation.
The second issue is that you need three groups to demonstrate the placebo effect, one that recieves a traditional medicine, one that recieves the placebo and a control group that recioeves no treatment.

It is incumbent upon you , as the person claiming that the placebo effect exists, to show research that demonstrates the effect.

Where is your evidence, or is this just a myth that people believe in?

 

[Mojo]

If you give a patient a therapy that is proven to be effective, You can tell them that it works without lying. Then they get the benefit of the placebo effect as well as the therapy.

And they are getting that, that is not the placebo effect.

The placebo effect operates with anything the patient thinks will be effective. It will work just as much in conjunction with a real and effective drug as it will with a sugar pill, if the patient has the same belief in it.

So as that is going on what exactly are you suggesting change? Doctors not informing patients about the side effects?

I'm not suggesting any change.

 

[brodski]

No. I don't think the NHS do feel that their funding for the homeopathic hospitals is a vehicle for placebo. The do it because they believe it works.

Not quite, some people believe that it is effective, but most of all the DoH believes that it is popular.

 

[Dancing David]

http://www.cochrane.org/reviews/en/ab003974.html

The Cochrane Database of Systematic Reviews 2006 Issue 3
Copyright © 2006 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

Outcome data were available in 156 out of 182 included trials, investigating 46 clinical conditions.
We found no statistically significant pooled effect of placebo in 38 studies with binary outcomes (4284 patients), relative risk 0.95 (95% confidence interval (CI) 0.89 to 1.01). The pooled relative risk for patient-reported outcomes was 0.95 (95% CI 0.88 to 1.03) and for observer-reported outcomes 0.91 (95% CI 0.81 to 1.03). There was heterogeneity (P=0.01) but the funnel plot was symmetrical. There was no statistically significant effect of placebo interventions in the four clinical conditions investigated in three trials or more: pain, nausea, smoking, and depression, but confidence intervals were wide.

 

[calebprime]

Saizai, I have yet to see you produce any research that the placebo effect actualy exists and that it is a substantial effect, as I said before all the studies I have seen would place it within random variation.
The second issue is that you need three groups to demonstrate the placebo effect, one that recieves a traditional medicine, one that recieves the placebo and a control group that recioeves no treatment.

It is incumbent upon you , as the person claiming that the placebo effect exists, to show research that demonstrates the effect.

Where is your evidence, or is this just a myth that people believe in?

The placebo effect operates with anything the patient thinks will be effective. It will work just as much in conjunction with a real and effective drug as it will with a sugar pill, if the patient has the same belief in it. I'm not suggesting any change.

Placebo effect.



Highlights mine.

Woops. It appears the quote from grayman from another thread isn't printing, and the link isn't working. He said, basically, that studies have shown that 75% of the effectiveness of anti-depressants is due to placebo effect. Let's assume such studies do exist, for the moment.

I don't have an agenda, I'm just asking questions.

1) Surely, all accounts from people taking anti-depressants supports the fact that these people feel different than without them. It's another question whether they are being cured of depression. Can we speak of placebo effect in cases where a drug is obviously psychoactive, as opposed to a sugar pill?

2) I'm very surprised to hear that the very existence of placebo effect is being questioned. Aren't there any studies that test whether placebos work better than no treatment at all? (Maybe this is something I've just assumed, wrongly.)

I consider this a live issue for many people. The related issue of the effectiveness of psychiatric treatment is pertinent at JREF because so often, people who claim paranormal abilities are being told to consult a psychiatrist.
Yet there is some question what, exactly the psychiatrist could actually DO for them, other than keep them out of trouble....

Hope this isn't off-topic. Tried to look for a thread where this is being discussed...

 

[Beth]

http://www.cochrane.org/reviews/en/ab003974.html

The Cochrane Database of Systematic Reviews 2006 Issue 3
Copyright © 2006 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.

And from the same abstract:

We found an overall effect of placebo treatments in 118 trials with continuous outcomes (7453 patients), standardised mean difference (SMD) -0.24 (95% CI -0.31 to -0.17).

 

[ponderingturtle]

2) I'm very surprised to hear that the very existence of placebo effect is being questioned. Aren't there any studies that test whether placebos work better than no treatment at all? (Maybe this is something I've just assumed, wrongly.)

The issue is this, is the placebo effect more than just observational bias introduced unconsiously by someone expecting a certain result?

I consider this a live issue for many people. The related issue of the effectiveness of psychiatric treatment is pertinent at JREF because so often, people who claim paranormal abilities are being told to consult a psychiatrist.
Yet there is some question what, exactly the psychiatrist could actually DO for them, other than keep them out of trouble....

Well psychiatrists do more than just prescribe drugs, there is that whole thearpy thing that you could say is one big placebo

 

[calebprime]

just to add: Dancing David, your post came up while I was typing mine.
Here's the "plain language" summary:

"No evidence that placebo treatments in general have important effects, although they may have small effects on patient-reported outcomes, for example pain

It has been widely believed that placebo (dummy) treatments (for example sugar tablets) are associated with substantial effects on a wide range of health problems. However, this belief is not based on evidence from randomised trials that use a placebo treatment for one group of people, while another group receives no treatment. The effect of placebo treatments was studied by reviewing more than 150 such trials covering many types of health care problems. Placebo treatments caused no major health benefits, although they possibly had a small effect on outcomes reported by patients, for example pain."

I buy this. My question now is: in the case of depression, are you "better" if you think you are? Not necessarily, I guess.

 

[ponderingturtle]

The placebo effect operates with anything the patient thinks will be effective. It will work just as much in conjunction with a real and effective drug as it will with a sugar pill, if the patient has the same belief in it. I'm not suggesting any change.

I don't get what you are actualy trying to do here. Give patients placebo's instead of drugs and use confidence tricks on them to get them to think that they did something, or use confidence tricks on people to get the same confermation bias with real medicine?

Remember that there are homeopathic studies that show that homeopathic cures work on animals, and there can be no placebo effect there becuase the animal doesn't know what it is taking? The reason is that there is still a confermation bias in the observers to see improvement in the test animals vs the control animals. So you need to remove the possibility of confermation bias on the behalf of the observer, and how do you do that? You make it so that they don't know who is getting a drug vs a placebo so that they view all patients the same and only when all the data is together can they see who got what.

There is no way to make a double blind experiment to test how well placebo's work, becuase you will always get the bais in the observer.

 

[andyandy]

Saizai, I have yet to see you produce any research that the placebo effect actualy exists and that it is a substantial effect, as I said before all the studies I have seen would place it within random variation.
The second issue is that you need three groups to demonstrate the placebo effect, one that recieves a traditional medicine, one that recieves the placebo and a control group that recioeves no treatment.

It is incumbent upon you , as the person claiming that the placebo effect exists, to show research that demonstrates the effect.

Where is your evidence, or is this just a myth that people believe in?

if placebo is a myth why is it standard practise to carry out double blinded trials? Is the medical establishment taken in as well?

 

[joobz]

if placebo is a myth why is it standard practise to carry out double blinded trials? Is the medical establishment taken in as well?

Double Blind trials aren't performed just because of a placebo effect. They are done to rule out ANY bias that may exist in the participants. If the placebo effect is found to be non-existant, that wouldn't negate the need for double blind trials.

 

[Mojo]

I don't get what you are actualy trying to do here. Give patients placebo's instead of drugs and use confidence tricks on them to get them to think that they did something, or use confidence tricks on people to get the same confermation bias with real medicine?

What makes you think I'm "actualy trying to do" anything here? Have I suggested anything like that? All I've done in this thread (apart from a brief digression into the apparent provision of therapeutic touch on the NHS) is to point out that the placebo effect will be invoked by any treatment that a patient believes will work, regardless of whether the treatment actually works, and pointed out that doctors (at least the ones I've seen) don't discourage their patients from thinking treatments will be effective.

Remember that there are homeopathic studies that show that homeopathic cures work on animals, and there can be no placebo effect there becuase the animal doesn't know what it is taking? The reason is that there is still a confermation bias in the observers to see improvement in the test animals vs the control animals. So you need to remove the possibility of confermation bias on the behalf of the observer, and how do you do that? You make it so that they don't know who is getting a drug vs a placebo so that they view all patients the same and only when all the data is together can they see who got what.

I wouldn't argue with that. Homoeopaths also claim that the fact that homoeopathy appears to work on babies and small children proves that the effects are real because the placebo effect doesn't apply to babies; conformation bias operates just as much as with animals, and presumably they've never heard of "mummy'll kiss it better"; surely the ultimate placebo!

There is no way to make a double blind experiment to test how well placebo's work, becuase you will always get the bais in the observer.

This is quite possibly what you would be measuring. I've yet to see any demonstration of a placebo treatment having objectively measurable effects that don't have an obvious psychological means of operation.

 

[Mojo]

Double Blind trials aren't performed just because of a placebo effect. They are done to rule out ANY bias that may exist in the participants. If the placebo effect is found to be non-existant, that wouldn't negate the need for double blind trials.

There is a school of thought that suggests that the placebo effect is nothing more than a result of bias in the participants.

 

[brodski]

if placebo is a myth why is it standard practise to carry out double blinded trials? Is the medical establishment taken in as well?

It depends what you mean by placebo, whether it is an actual heeling effect, or whether it is just a failure of accurate and objective measurement and observation. In other words, do people actually get better, or do they just say that they feel better? Furthermore placebo also covers things such as "regression to the mean", most medical conditions fluctuate in severity over time, and many get better on their own. Placebo control may just be a way of knowing what effect a treatment has over and above those random fluctuations and failures of measurement.

 

[joobz]

There is a school of thought that suggests that the placebo effect is nothing more than a result of bias in the participants.

True. I was simply stating that it was the bias that was controlled against, no matter what you call it.

 

[ponderingturtle]

if placebo is a myth why is it standard practise to carry out double blinded trials? Is the medical establishment taken in as well?

Please look into critisisms of homeopathic studies that show that they are effective in treating animals. If the doctor knew who was getting placebos vs who was getting the drug it would be single blind not double blind

 

[ponderingturtle]

What makes you think I'm "actualy trying to do" anything here? Have I suggested anything like that? All I've done in this thread (apart from a brief digression into the apparent provision of therapeutic touch on the NHS) is to point out that the placebo effect will be invoked by any treatment that a patient believes will work, regardless of whether the treatment actually works, and pointed out that doctors (at least the ones I've seen) don't discourage their patients from thinking treatments will be effective.

Um ok I thought you where argueing in favor of doctors trying to use the placebo effect more, which must mean that patients get either unrealistic expectations or other bad information

 

[andyandy]

ok this is from the http://skepdic.com/placebo.html website

Some believe the placebo effect is psychological, due to a belief in the treatment or to a subjective feeling of improvement. Irving Kirsch, a psychologist at the University of Connecticut, believes that the effectiveness of Prozac and similar drugs may be attributed almost entirely to the placebo effect. He and Guy Sapirstein analyzed 19 clinical trials of antidepressants and concluded that the expectation of improvement, not adjustments in brain chemistry, accounted for 75 percent of the drugs' effectiveness (Kirsch 1998). "The critical factor," says Kirsch, "is our beliefs about what's going to happen to us. You don't have to rely on drugs to see profound transformation." In an earlier study, Sapirstein analyzed 39 studies, done between 1974 and 1995, of depressed patients treated with drugs, psychotherapy, or a combination of both. He found that 50 percent of the drug effect is due to the placebo response.

A person's beliefs and hopes about a treatment, combined with their suggestibility, may have a significant biochemical effect. Sensory experience and thoughts can affect neurochemistry. The body's neurochemical system affects and is affected by other biochemical systems, including the hormonal and immune systems. Thus, it is consistent with current knowledge that a person's hopeful attitude and beliefs may be very important to their physical well-being and recovery from injury or illness.

However, it may be that much of the placebo effect is not a matter of mind over molecules, but of mind over behavior. A part of the behavior of a "sick" person is learned. So is part of the behavior of a person in pain. In short, there is a certain amount of role-playing by ill or hurt people. Role-playing is not the same as faking or malingering. The behavior of sick or injured persons is socially and culturally based to some extent. The placebo effect may be a measurement of changed behavior affected by a belief in the treatment. The changed behavior includes a change in attitude, in what one says about how one feels, and how one acts. It may also affect one's body chemistry.

The psychological explanation seems to be the one most commonly believed. Perhaps this is why many people are dismayed when they are told that the effective drug they are taking is a placebo. This makes them think that their problem is "all in their mind" and that there is really nothing wrong with them. Yet, there are too many studies which have found objective improvements in health from placebos to support the notion that the placebo effect is entirely psychological.

with some question as to the effectiveness of placebo

The powerful effect of the placebo is not in doubt. It should be, however, according to Danish researchers Asbjørn Hróbjartsson and Peter C. Götzsche. Their meta-study of 114 studies involving placebos found "little evidence in general that placebos had powerful clinical effects...[and]...compared with no treatment, placebo had no significant effect on binary outcomes, regardless of whether these outcomes were subjective or objective. For the trials with continuous outcomes, placebo had a beneficial effect, but the effect decreased with increasing sample size, indicating a possible bias related to the effects of small trials ("Is the Placebo Powerless? An Analysis of Clinical Trials Comparing Placebo with No Treatment," The New England Journal of Medicine, May 24, 2001 (Vol. 344, No. 21)."

According to Dr. Hróbjartsson, professor of medical philosophy and research methodology at University of Copenhagen, "The high levels of placebo effect which have been repeatedly reported in many articles, in our mind are the result of flawed research methodology."* This claim flies in the face of more than fifty years of research. At the very least, we can expect to see more rigorously designed research projects trying to disprove Hróbjartsson and Götzsche.

but it would suggest that this research whilst interesting, would require further investigation before concluding that placebo was "powerless"......

 

[andyandy]

and a good summary of the ethical dilemma of placebo....

The power of the placebo effect has led to an ethical dilemma. One should not deceive other people, but one should relieve the pain and suffering of one's patients. Should one use deception to benefit one's patients? Is it unethical for a doctor to knowingly prescribe a placebo without informing the patient? If informing the patient reduces the effectiveness of the placebo, is some sort of deception warranted in order to benefit the patient? Some doctors think it is justified to use a placebo in those types of cases where a strong placebo effect has been shown and where distress is an aggravating factor.* Others think it is always wrong to deceive the patient and that informed consent requires that the patient be told that a treatment is a placebo treatment. Others, especially "alternative" medicine practitioners, don't even want to know whether a treatment is a placebo or not. Their attitude is that as long as the treatment is effective, who cares if it a placebo? Of course, if the placebo effect is an illusion, then another ethical dilemma arises: should placebos be given if it is known that deception does not really reduce pain or aid in the cure of anything?