Hallo. I would like to paericipate in setting questions on statistics and evidence based practice.send me the details.Thank you.

Sent from my Nokia phone
-----Original Message-----
From: EVIDENCE-BASED-HEALTH automatic digest system
Sent:  10/03/2011 3:02:23 am
Subject:  EVIDENCE-BASED-HEALTH Digest - 8 Mar 2011 to 9 Mar 2011 (#2011-62)

There are 8 messages totaling 2351 lines in this issue.

Topics of the day:

  1. Statistics questions needed (2)
  2. placebos (5)
  3. informed consent

----------------------------------------------------------------------

Date:    Wed, 9 Mar 2011 09:15:50 +0000
From:    Kieran Walsh <[log in to unmask]>
Subject: Statistics questions needed

Dear Group, 
We are looking for people who would like to write multiple choice 
questions on statistics or evidence based medicine for the BMJ Group. This 
is for BMJ Onexamination - an MCQ database to help doctors pass exams. 
We can pay for accepted questions. Would you like to write questions for 
us? Please let me know and I will send more information on what we are 
after. 
Many thanks, 
Yours, 
Kieran, 
Dr. Kieran Walsh, 
Editor, 
BMJ Learning 

_______________________________________________________________________
The BMJ Group is one of the world's most trusted providers of medical information for doctors, researchers, health care workers and patients group.bmj.com.  This email and any attachments are confidential.  If you have received this email in error, please delete it and kindly notify us.  If the email contains personal views then the BMJ Group accepts no responsibility for these statements.  The recipient should check this email and attachments for viruses because the BMJ Group accepts no liability for any damage caused by viruses.  Emails sent or received by the BMJ Group may be monitored for size, traffic, distribution and content.  BMJ Publishing Group Limited trading as BMJ Group.  A private limited company, registered in England and Wales under registration number 03102371.  Registered office: BMA House, Tavistock Square, London WC1H 9JR, UK.

------------------------------

Date:    Wed, 9 Mar 2011 10:13:54 +0000
From:    Michael Power <[log in to unmask]>
Subject: Re: placebos

[Message contains invalid MIME fields or encoding and could not be processed]

------------------------------

Date:    Wed, 9 Mar 2011 10:24:15 +0000
From:    Caroline Boulind <[log in to unmask]>
Subject: Re: placebos

Thank you Michael, that was really interesting.
I struggle a little with the placebo effect. I am doing a lot of
reading at the moment (and writing) about the use of placebo
interventions in surgical trials. This is, understandably, a contentious
and much debated topic. What I struggle with is the importance of the
placebo effect. I am playing devil's advocate a little here, and I don't
necessarily think that placebo's should be used in lieu of active
treatments. But if, for example, a sham surgical procedure results in
improvement of sympotms of a greater magnitude than the best medical
therapy even though no definitive procedure was performed, does it
matter that it was a placebo effect? It is argued that the risk of
placebo surgical interventions is too high and cannot be balanced by
potential benefit for patients becuase sham procedures don't provide any
potential for cure or amelioration, but if the placebo effect is
efficacious in making patients feel better is that not enough?

Caroline
 
Dr. Caroline Boulind
Clinical Research Fellow
01935 384559

>>> Michael Power <[log in to unmask]> 09/03/2011 10:13 >>>

I have followed this thread of discussion with interest because, for
me, the placebo effect is one of life’s two great mysteries — the
other is economics. Actually, behavioural economics and the placebo
effect could be considered the same mystery. Both are present in every
human interaction, are poorly understood, and their complexity is belied
by the simple terminology. For example, the “placebo effect” is not
due to the placebo (it is due to the mode and contex of delivery of the
placebo), and it is not one effect, but many effects. Some placebo
effects are non-specific, some are specific (analgesia), some effects
are desirable, some are unwanted, and some effects are best thought of
as measurement artefacts such as the natural course of the condition,
regression to the mean, bias in subjective outcome measures, and most
insidiously a “negative” effect in the control group being taken for
a “positive” effect in the test group when only the difference
between the two groups is considered.
Reviews of the placebo effect (even the chapter in “Bad Science” by
EBM hero Ben Goldacre) tend to cherry pick the evidence. And, much of
the selected evidence comes from studies of North American psychology
students, although it not clear how well this applies to patients in the
pharmacy, in the consulting room, or in a hospital bed.
The important practical questions have not been answered by research.
How can desirable placebo effects be optimized? 
How can undesirable placebo effects be minimized? 
When are the biases introduced by measurement artefacts clinically
important, and when are they negligible? 

The groups for whom these questions are most urgent, seem to show the
least awareness of their importance. The groups I am referring to are,
of course, health care professionals, the promoters of integrative
medicine, and the practitioners of complementary and alternative
medicine.
To answer these questions we need to understand the roles, uses, and
abuses of social grooming and branding.
Social grooming in humans is much more than looking for lice in your
child’s hair. If you want to know more, good places to start are:
tiny.cc/SocialGroomingDunbar 
tiny.cc/SocialGroomingJacobs1 
tiny.cc/SocialGroomingJacobs2
I strongly suspect that social grooming is the most important cause of
desirable placebo effects. Social grooming explains why acupuncture,
chiropractic, homeopathy and other CAMs are thought to be useful. Social
grooming also helps explain why well-meaning advocates of evidence-based
practice paradoxically can advocate integrative medicine without being
disturbed by cognitive dissonance given the evidence of lack of specific
effects for CAM. However, social grooming does not explain the lack of
interest in research that would explain the mechanisms of placebo
effects in CAM.
Branding is vital in marketing products and services, including
healthcare and pastoral care. Branding manipulates what Ted Kaptchuk
calls the “meaning response” in his publications on the placebo
effect. Harley Street, Great Ormond Street, the Mayo Clinic all have
great brands. It would be really interesting to know how strongly this
amplifies placebo effects.
CAM therapies obsessively protect their brands. I strongly suspect that
the reason for this has as much to do with branding amplifying placebo
effects as with branding amplifying market segmentation of products and
services. For example acupuncture is not just needling, it is always
promoted as a traditional Chinese therapy in use for more than 2000
years to correct imbalances of energy flows; chiropractic is not just
spinal manipulation, it is adjustment of spinal subluxations to correct
pressure on nerves; homeopathy is not just treating like with
astronomically small concentrations of like, it is the use of
impractically tiny pillules that must move from the container to your
mouth without being contaminated by your hands.
Take the branding (theatricality, magical explanations, seeming
authority, and celebrity endorsement) away and all CAM therapies and
many conventional treatments will lose both their appeal and their
effectiveness.
Michael
NHS Clinical Knowledge Summaries Service www.cks.nhs.uk.
Sowerby Centre for Health Informatics at Newcastle Ltd www.schin.co.uk


This e-mail and any attachments may contain confidential and
privileged information. If you are not the intended recipient,
please notify the sender immediately by return e-mail, delete this
e-mail and destroy any copies. Any dissemination or use of this
information by a person other than the intended recipient is

------------------------------

Date:    Wed, 9 Mar 2011 12:58:55 +0000
From:    Stephen Senn <[log in to unmask]>
Subject: Re: placebos

Dear Caroline and Michael (and others),
As has already been pointed out by a number of correspondents, convincing evidence of a placebo effect that is not just regression to the mean is lacking for most indications (pain control is the exception). Here are some discussions of this, some of which have been cited before in this thread

1.         McDonald, CJ, Mazzuca, SA, McCabe, GP, Jr. How much of the placebo 'effect' is really statistical regression?, Statistics in Medicine 1983; 2: 417-427.
2.         Senn, SJ. How much of the placebo 'effect' is really statistical regression? [letter], Statistics in Medicine 1988; 7: 1203.
3.         Kienle, GS, Kiene, H. The powerful placebo effect: fact or fiction?, Journal of Clinical Epidemiology 1997; 50: 1311-1318.
4.         Hrobjartsson, A, Gotzsche, PC. Placebo treatment versus no treatment, Cochrane Database Syst Rev 2003: CD003974.
5.         Hrobjartsson, A, Gotzsche, PC. Is the placebo powerless? Update of a systematic review with 52 new randomized trials comparing placebo with no treatment, Journal of Internal Medicine 2004; 256: 91-100.

A related point, however, is that use of placebo except in the context of a randomised trial, involves a violation of consent (from one point of view). This is discussed in
6.         Senn, SJ. Are placebo run ins justified?, British Medical Journal 1997; 314: 1191-1193.


Regards
Stephen

From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Caroline Boulind
Sent: 09 March 2011 10:24
To: [log in to unmask]
Subject: Re: placebos

Thank you Michael, that was really interesting.
I struggle a little with the placebo effect. I am doing a lot of reading at the moment (and writing) about the use of placebo interventions in surgical trials. This is, understandably, a contentious and much debated topic. What I struggle with is the importance of the placebo effect. I am playing devil's advocate a little here, and I don't necessarily think that placebo's should be used in lieu of active treatments. But if, for example, a sham surgical procedure results in improvement of sympotms of a greater magnitude than the best medical therapy even though no definitive procedure was performed, does it matter that it was a placebo effect? It is argued that the risk of placebo surgical interventions is too high and cannot be balanced by potential benefit for patients becuase sham procedures don't provide any potential for cure or amelioration, but if the placebo effect is efficacious in making patients feel better is that not enough?

Caroline

Dr. Caroline Boulind
Clinical Research Fellow
01935 384559

>>> Michael Power <[log in to unmask]> 09/03/2011 10:13 >>>

I have followed this thread of discussion with interest because, for me, the placebo effect is one of life’s two great mysteries — the other is economics. Actually, behavioural economics and the placebo effect could be considered the same mystery. Both are present in every human interaction, are poorly understood, and their complexity is belied by the simple terminology. For example, the “placebo effect” is not due to the placebo (it is due to the mode and contex of delivery of the placebo), and it is not one effect, but many effects. Some placebo effects are non-specific, some are specific (analgesia), some effects are desirable, some are unwanted, and some effects are best thought of as measurement artefacts such as the natural course of the condition, regression to the mean, bias in subjective outcome measures, and most insidiously a “negative” effect in the control group being taken for a “positive” effect in the test group when only the difference between the two groups is considered.

Reviews of the placebo effect (even the chapter in “Bad Science” by EBM hero Ben Goldacre) tend to cherry pick the evidence. And, much of the selected evidence comes from studies of North American psychology students, although it not clear how well this applies to patients in the pharmacy, in the consulting room, or in a hospital bed.

The important practical questions have not been answered by research.

 *   How can desirable placebo effects be optimized?
 *   How can undesirable placebo effects be minimized?
 *   When are the biases introduced by measurement artefacts clinically important, and when are they negligible?

The groups for whom these questions are most urgent, seem to show the least awareness of their importance. The groups I am referring to are, of course, health care professionals, the promoters of integrative medicine, and the practitioners of complementary and alternative medicine.

To answer these questions we need to understand the roles, uses, and abuses of social grooming and branding.

Social grooming in humans is much more than looking for lice in your child’s hair. If you want to know more, good places to start are:

tiny.cc/SocialGroomingDunbar <http://tiny.cc/SocialGroomingDunbar>

tiny.cc/SocialGroomingJacobs1 <http://tiny.cc/SocialGroomingJacobs1>

tiny.cc/SocialGroomingJacobs2<http://tiny.cc/SocialGroomingJacobs2>

I strongly suspect that social grooming is the most important cause of desirable placebo effects. Social grooming explains why acupuncture, chiropractic, homeopathy and other CAMs are thought to be useful. Social grooming also helps explain why well-meaning advocates of evidence-based practice paradoxically can advocate integrative medicine without being disturbed by cognitive dissonance given the evidence of lack of specific effects for CAM. However, social grooming does not explain the lack of interest in research that would explain the mechanisms of placebo effects in CAM.

Branding is vital in marketing products and services, including healthcare and pastoral care. Branding manipulates what Ted Kaptchuk calls the “meaning response” in his publications on the placebo effect. Harley Street, Great Ormond Street, the Mayo Clinic all have great brands. It would be really interesting to know how strongly this amplifies placebo effects.

CAM therapies obsessively protect their brands. I strongly suspect that the reason for this has as much to do with branding amplifying placebo effects as with branding amplifying market segmentation of products and services. For example acupuncture is not just needling, it is always promoted as a traditional Chinese therapy in use for more than 2000 years to correct imbalances of energy flows; chiropractic is not just spinal manipulation, it is adjustment of spinal subluxations to correct pressure on nerves; homeopathy is not just treating like with astronomically small concentrations of like, it is the use of impractically tiny pillules that must move from the container to your mouth without being contaminated by your hands.

Take the branding (theatricality, magical explanations, seeming authority, and celebrity endorsement) away and all CAM therapies and many conventional treatments will lose both their appeal and their effectiveness.

Michael

NHS Clinical Knowledge Summaries Service www.cks.nhs.uk<http://www.cks.nhs.uk>.
Sowerby Centre for Health Informatics at Newcastle Ltd www.schin.co.uk<http://www.schin.co.uk>

This e-mail and any attachments may contain confidential and
privileged information. If you are not the intended recipient,
please notify the sender immediately by return e-mail, delete this
e-mail and destroy any copies. Any dissemination or use of this
information by a person other than the intended recipient is
unauthorized and may be illegal.

------------------------------

Date:    Wed, 9 Mar 2011 06:43:33 -0800
From:    "Dr. Raddadi" <[log in to unmask]>
Subject: Re: Statistics questions needed



Dear Kieran

 Kindly provide me with more information regarding the areas for example is it 
applied biostatistics or statistical methods in epidemiology etc....
Best wishes
 
Rajaa Al-Raddadi, MBBS,ABCM,RICR
Consultant Community Medicine and epidemiologist
Head of Research Department, PHC, Jeddah, Saudi Arabia
Vice president, Saudi Epidemiology Association
 


________________________________

From: Kieran Walsh <[log in to unmask]>
To: [log in to unmask]
Sent: Wed, March 9, 2011 12:15:50 PM
Subject: Statistics questions needed

Dear Group, 
We are looking for people who would like to write multiple choice questions on 
statistics or evidence based medicine for the BMJ Group. This is for BMJ 
Onexamination - an MCQ database to help doctors pass exams.   

We can pay for accepted questions. Would you like to write questions for us? 
Please let me know and I will send more information on what we are after.     

Many thanks,   
Yours, 
Kieran,   
Dr. Kieran Walsh, 
Editor, 
BMJ Learning 
_______________________________________________________________________
The BMJ Group is one of the world's most trusted providers of medical 
information for doctors, researchers, health care workers and patients 
group.bmj.com. This email and any attachments are confidential. If you have 
received this email in error, please delete it and kindly notify us. If the 
email contains personal views then the BMJ Group accepts no responsibility for 
these statements. The recipient should check this email and attachments for 
viruses because the BMJ Group accepts no liability for any damage caused by 
viruses. Emails sent or received by the BMJ Group may be monitored for size, 
traffic, distribution and content. BMJ Publishing Group Limited trading as BMJ 
Group. A private limited company, registered in England and Wales under 
registration number 03102371. Registered office: BMA House, Tavistock Square, 
London WC1H 9JR, UK.
___________________________

------------------------------

Date:    Wed, 9 Mar 2011 16:36:42 +0000
From:    C Klim McPherson <[log in to unmask]>
Subject: Re: placebos

Compliance bias – a close relative  - is originally well documented in the Coronary Drug Project, NEJM 1980:303:1038-41

And the evidence synthesised subsequently in BMJ 2006;333:15-

Plausibly this is why HRT looked cardioprotective in observational studies but not in double blind RCT's

Klim

From: Stephen Senn <[log in to unmask]<mailto:[log in to unmask]>>
Reply-To: Stephen Senn <[log in to unmask]<mailto:[log in to unmask]>> cardioprotective
Date: Wed, 9 Mar 2011 12:58:55 +0000
To: "[log in to unmask]<mailto:[log in to unmask]>" <[log in to unmask]<mailto:[log in to unmask]>>
Subject: Re: placebos

Dear Caroline and Michael (and others),
As has already been pointed out by a number of correspondents, convincing evidence of a placebo effect that is not just regression to the mean is lacking for most indications (pain control is the exception). Here are some discussions of this, some of which have been cited before in this thread

1.         McDonald, CJ, Mazzuca, SA, McCabe, GP, Jr. How much of the placebo 'effect' is really statistical regression?, Statistics in Medicine 1983; 2: 417-427.
2.         Senn, SJ. How much of the placebo 'effect' is really statistical regression? [letter], Statistics in Medicine 1988; 7: 1203.
3.         Kienle, GS, Kiene, H. The powerful placebo effect: fact or fiction?, Journal of Clinical Epidemiology 1997; 50: 1311-1318.
4.         Hrobjartsson, A, Gotzsche, PC. Placebo treatment versus no treatment, Cochrane Database Syst Rev 2003: CD003974.
5.         Hrobjartsson, A, Gotzsche, PC. Is the placebo powerless? Update of a systematic review with 52 new randomized trials comparing placebo with no treatment, Journal ofInternal Medicine 2004; 256: 91-100.

A related point, however, is that use of placebo except in the context of a randomised trial, involves a violation of consent (from one point of view). This is discussed in
6.         Senn, SJ. Are placebo run ins justified?, British Medical Journal 1997; 314: 1191-1193.


Regards
Stephen

From: Evidence based health (EBH) [mailto:[log in to unmask]] On Behalf Of Caroline Boulind
Sent: 09 March 2011 10:24
To: [log in to unmask]<mailto:[log in to unmask]>
Subject: Re: placebos

Thank you Michael, that was really interesting.
I struggle a little with the placebo effect. I am doing a lot of reading at the moment (and writing) about the use of placebo interventions in surgical trials. This is, understandably, a contentious and much debated topic. What I struggle with is the importance of the placebo effect. I am playing devil's advocate a little here, and I don't necessarily think that placebo's should be used in lieu of active treatments. But if, for example, a sham surgical procedure results in improvement of sympotms of a greater magnitude than the best medical therapy even though no definitive procedure was performed, does it matter that it was a placebo effect? It is argued that the risk of placebo surgical interventions is too high and cannot be balanced by potential benefit for patients becuase sham procedures don't provide anypotential for cure or amelioration, but if the placebo effect is efficacious in making patients feel better is that not enough?

Caroline

Dr. Caroline Boulind
Clinical Research Fellow
01935 384559

>>> Michael Power <[log in to unmask]<mailto:[log in to unmask]>> 09/03/2011 10:13 >>>

I have followed this thread of discussion with interest because, for me, the placebo effect is one of life’s two great mysteries — the other is economics. Actually, behavioural economics and the placebo effect could be considered the same mystery. Both are present in every human interaction, are poorly understood, and their complexity is belied by the simple terminology. For example, the “placebo effect” is not due to the placebo (it is due to the mode and contex of delivery of the placebo), and it is not one effect, but many effects. Some placebo effects are non-specific, some are specific (analgesia), some effects are desirable, some are unwanted, and some effects are best thought of as measurement artefacts such as the natural course of the condition, regression to the mean, bias in subjective outcome measures, andmost insidiously a “negative” effect in the control group being taken for a “positive” effect in the test group when only the difference between the two groups is considered.

Reviews of the placebo effect (even the chapter in “Bad Science” by EBM hero Ben Goldacre) tend to cherry pick the evidence. And, much of the selected evidence comes from studies of North American psychology students,although it not clear how well this applies to patients in the pharmacy, in the consulting room, or in a hospital bed.

The important practical questions have not been answered by research.

 *   How can desirable placebo effects be optimized?
 *   How can undesirable placebo effects be minimized?
 *   When are the biases introduced by measurement artefacts clinically important, and when are they negligible?

The groups for whom these questions are most urgent, seem to show the least awareness of their importance. The groups I am referring to are, of course,health care professionals, the promoters of integrative medicine, and the practitioners of complementary and alternative medicine.

To answer these questions we need to understand the roles, uses, and abuses of social grooming and branding.

Social grooming in humans is much more than looking for lice in your child’s hair. If you want to know more, good places to start are:

tiny.cc/SocialGroomingDunbar <http://tiny.cc/SocialGroomingDunbar>

tiny.cc/SocialGroomingJacobs1 <http://tiny.cc/SocialGroomingJacobs1>

tiny.cc/SocialGroomingJacobs2<http://tiny.cc/SocialGroomingJacobs2>

I strongly suspect that social grooming is the most important cause of desirable placebo effects. Social grooming explains why acupuncture, chiropractic, homeopathy and other CAMs are thought to be useful. Social grooming also helps explain why well-meaning advocates of evidence-based practice paradoxically can advocate integrative medicine without being disturbed by cognitive dissonance given the evidence of lack of specific effects for CAM. However, social grooming does not explain the lack of interest in research that would explain the mechanisms of placebo effects in CAM.

Branding is vital in marketing products and services, including healthcare and pastoral care. Branding manipulates what Ted Kaptchuk calls the “meaning response” in his publications on the placebo effect. Harley Street, Great Ormond Street, the Mayo Clinic all have great brands. It would be really interesting to know how strongly this amplifies placebo effects.

CAM therapies obsessively protect their brands. I strongly suspect that the reason for this has as much to do with branding amplifying placebo effects as with branding amplifying market segmentation of products and services. For example acupuncture is not just needling, it is always promoted as a traditional Chinese therapy in use for more than 2000 years to correct imbalances of energy flows; chiropractic is not just spinal manipulation, it is adjustment of spinal subluxations to correct pressure on nerves; homeopathy is not just treating like with astronomically small concentrations of like, it is the use of impractically tiny pillules that must move from the container toyour mouth without being contaminated by your hands.

Take the branding (theatricality, magical explanations, seeming authority, and celebrity endorsement) away and all CAM therapies and many conventionaltreatments will lose both their appeal and their effectiveness.

Michael

NHS Clinical Knowledge Summaries Service www.cks.nhs.uk<http://www.cks.nhs.uk>.
Sowerby Centre for Health Informatics at Newcastle Ltd www.schin.co.uk<http://www.schin.co.uk>

This e-mail and any attachments may contain confidential and
privileged information. If you are not the intended recipient,
please notify the sender immediately by return e-mail, delete this
e-mail and destroy any copies. Any dissemination or use of this
information by a person other than the intended recipient is
unauthorized and may be illegal.

------------------------------

Date:    Wed, 9 Mar 2011 21:26:20 +0000
From:    Michael Power <[log in to unmask]>
Subject: Re: placebos

Thanks Caroline

I haven’t looked closely at the ethical problems of including a placebo arm in a controlled trial. But, I can’t see how a placebo arm could be considered unethical if participants were (a) fully informed; (b) their preferences were documented and included in the analysis of the results;  and (c) their choice was freely made and clearly documented.

By fully informed I mean that patients in the trial understand:

·         The estimated chance of benefits, and the uncertainties around these estimates — there are 2 types of uncertainty:  (i) precision, eg 95% confidence interval) and (ii) accuracy, ie risks of biases

·         The estimated chance of harms, and the uncertainties around these estimates

·         That framing the presentation of benefits and harms can change people’s decisions, so these need to be looked at from opposing points of view.

And, that they were helped to understand and communicate the values that they place on the potential benefits and harms.

The ethics of offering a placebo treatment are different outside a controlled trial. In this case I think that, after diligent consideration of the issues, most people would consider it unethical to offer a placebo treatment without full disclosure and informed consent.

If the placebo treatment is surgical, and this has been found to be more effective than current medical treatment, one would have to ask, in the trials providing the evidence:

·         Were the patients fully informed according to the criteria above?

·         Were the results biased, eg by “resentful demoralization”? (see reference 1, 2)

·         Were the providers of the medical treatment optimizing their opportunities for ethically enhancing desirable placebo effects?

The answers to these questions might change your gut feeling that placebo surgery treatment is evidence-based and ethical.

Because people (patients, providers, researchers) find it difficult to understand and communicate risk and uncertainty, these may be impractically high standards to meet. But, this is not a justification for not trying.

Michael

References

1 Cook TD, Campbell DT. Quasi-experimentation: design and analysis issues for field settings. Chicago: Rand McNally, 1979

2. http://onlinelibrary.wiley.com/doi/10.1002/0470013192.bsa561/abstract



From: Caroline Boulind [mailto:[log in to unmask]]
Sent: 09 March 2011 10:24
To: [log in to unmask]; Michael Power
Subject: Re: placebos

Thank you Michael, that was really interesting.
I struggle a little with the placebo effect. I am doing a lot of reading at the moment (and writing) about the use of placebo interventions in surgical trials. This is, understandably, a contentious and much debated topic. What I struggle with is the importance of the placebo effect. I am playing devil's advocate a little here, and I don't necessarily think that placebo's should be used in lieu of active treatments. But if, for example, a sham surgical procedure results in improvement of sympotms of a greater magnitude than the best medical therapy even though no definitive procedure was performed, does it matter that it was a placebo effect? It is argued that the risk of placebo surgical interventions is too high and cannot be balanced by potential benefit for patients becuase sham procedures don't provide any potential for cure or amelioration, but if the placebo effect is efficacious in making patients feel better is that not enough?

Caroline

Dr. Caroline Boulind
Clinical Research Fellow
01935 384559

>>> Michael Power <[log in to unmask]> 09/03/2011 10:13 >>>

I have followed this thread of discussion with interest because, for me, the placebo effect is one of life’s two great mysteries — the other is economics. Actually, behavioural economics and the placebo effect could be considered the same mystery. Both are present in every human interaction, are poorly understood, and their complexity is belied by the simple terminology. For example, the “placebo effect” is not due to the placebo (it is due to the mode and contex of delivery of the placebo), and it is not one effect, but many effects. Some placebo effects are non-specific, some are specific (analgesia), some effects are desirable, some are unwanted, and some effects are best thought of as measurement artefacts such as the natural course of the condition, regression to the mean, bias in subjective outcome measures, and most insidiously a “negative” effect in the control group being taken for a “positive” effect in the test group when only the difference between the two groups is considered.

Reviews of the placebo effect (even the chapter in “Bad Science” by EBM hero Ben Goldacre) tend to cherry pick the evidence. And, much of the selected evidence comes from studies of North American psychology students, although it not clear how well this applies to patients in the pharmacy, in the consulting room, or in a hospital bed.

The important practical questions have not been answered by research.

 *   How can desirable placebo effects be optimized?
 *   How can undesirable placebo effects be minimized?
 *   When are the biases introduced by measurement artefacts clinically important, and when are they negligible?

The groups for whom these questions are most urgent, seem to show the least awareness of their importance. The groups I am referring to are, of course, health care professionals, the promoters of integrative medicine, and the practitioners of complementary and alternative medicine.

To answer these questions we need to understand the roles, uses, and abuses of social grooming and branding.

Social grooming in humans is much more than looking for lice in your child’s hair. If you want to know more, good places to start are:

tiny.cc/SocialGroomingDunbar <http://tiny.cc/SocialGroomingDunbar>

tiny.cc/SocialGroomingJacobs1 <http://tiny.cc/SocialGroomingJacobs1>

tiny.cc/SocialGroomingJacobs2<http://tiny.cc/SocialGroomingJacobs2>

I strongly suspect that social grooming is the most important cause of desirable placebo effects. Social grooming explains why acupuncture, chiropractic, homeopathy and other CAMs are thought to be useful. Social grooming also helps explain why well-meaning advocates of evidence-based practice paradoxically can advocate integrative medicine without being disturbed by cognitive dissonance given the evidence of lack of specific effects for CAM. However, social grooming does not explain the lack of interest in research that would explain the mechanisms of placebo effects in CAM.

Branding is vital in marketing products and services, including healthcare and pastoral care. Branding manipulates what Ted Kaptchuk calls the “meaning response” in his publications on the placebo effect. Harley Street, Great Ormond Street, the Mayo Clinic all have great brands. It would be really interesting to know how strongly this amplifies placebo effects.

CAM therapies obsessively protect their brands. I strongly suspect that the reason for this has as much to do with branding amplifying placebo effects as with branding amplifying market segmentation of products and services. For example acupuncture is not just needling, it is always promoted as a traditional Chinese therapy in use for more than 2000 years to correct imbalances of energy flows; chiropractic is not just spinal manipulation, it is adjustment of spinal subluxations to correct pressure on nerves; homeopathy is not just treating like with astronomically small concentrations of like, it is the use of impractically tiny pillules that must move from the container to your mouth without being contaminated by your hands.

Take the branding (theatricality, magical explanations, seeming authority, and celebrity endorsement) away and all CAM therapies and many conventional treatments will lose both their appeal and their effectiveness.

Michael

NHS Clinical Knowledge Summaries Service www.cks.nhs.uk<http://www.cks.nhs.uk>.
Sowerby Centre for Health Informatics at Newcastle Ltd www.schin.co.uk<http://www.schin.co.uk>

This e-mail and any attachments may contain confidential and
privileged information. If you are not the intended recipient,
please notify the sender immediately by return e-mail, delete this
e-mail and destroy any copies. Any dissemination or use of this
information by a person other than the intended recipient is
unauthorized and may be illegal.

------------------------------

Date:    Wed, 9 Mar 2011 14:41:39 -0700
From:    write words <[log in to unmask]>
Subject: Re: informed consent

Michael's definition of an informed patient makes sense, but how do you know whether the patient truly understands this?

A recent New York Times article describes research into the attitudes of patients who participate in clinical trials.

You can read the story here: http://www.nytimes.com/2011/03/03/health/views/03chen.html

But here's the takeaway:
The ethicists surveyed 70 patients enrolled in several early-phase cancer trials and asked them about their expectations and understanding of their respective trials. A solid majority understood that the trials’ purpose was to advance research, not to treat them. But despite clearly understanding the purpose, and limits, of early-phase trials, the patients were also blinded by what researchers called an “unrealistic optimism,” or an optimistic bias, when it came to applying that knowledge to their own particular situations. A majority of patients assumed that the experimental drugs would control their cancer and that they would experience benefits but not complications.

cheers,
Christie
        
Christie Aschwanden
www.christieaschwanden.com


On Mar 9, 2011, at 2:26 PM, Michael Power wrote:

> Thanks Caroline
>  
> I haven’t looked closely at the ethical problems of including a placebo arm in a controlled trial. But, I can’t see how a placebo arm could be considered unethical if participants were (a) fully informed; (b) their preferences were documented and included in the analysis of the results;  and (c) their choice was freely made and clearly documented.
>  
> By fully informed I mean that patients in the trial understand:
> ·         The estimated chance of benefits, and the uncertainties around these estimates — there are 2 types of uncertainty:  (i) precision, eg 95% confidence interval) and (ii) accuracy, ie risks of biases
> ·         The estimated chance of harms, and the uncertainties around these estimates
> ·         That framing the presentation of benefits and harms can change people’s decisions, so these need to be looked at from opposing points of view.
>  
> And, that they were helped to understand and communicate the values that they place on the potential benefits and harms.
>  
> The ethics of offering a placebo treatment are different outside a controlled trial. In this case I think that, after diligent consideration of the issues, most people would consider it unethical to offer a placebo treatment without full disclosure and informed consent.
>  
> If the placebo treatment is surgical, and this has been found to be more effective than current medical treatment, one would have to ask, in the trials providing the evidence:
> ·         Were the patients fully informed according to the criteria above?
> ·         Were the results biased, eg by “resentful demoralization”? (see reference 1, 2)
> ·         Were the providers of the medical treatment optimizing their opportunities for ethically enhancing desirable placebo effects?
>  
> The answers to these questions might change your gut feeling that placebo surgery treatment is evidence-based and ethical.
>  
> Because people (patients, providers, researchers) find it difficult to understand and communicate risk and uncertainty, these may be impractically high standards to meet. But, this is not a justification for not trying.
>  
> Michael
>  
> References
>  
> 1 Cook TD, Campbell DT. Quasi-experimentation: design and analysis issues for field settings. Chicago: Rand McNally, 1979
>  
> 2. http://onlinelibrary.wiley.com/doi/10.1002/0470013192.bsa561/abstract
>  

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End of EVIDENCE-BASED-HEALTH Digest - 8 Mar 2011 to 9 Mar 2011 (#2011-62)
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