Social and judgmental biases that make inert treatments seem to work
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|Oggetto: Social and judgmental biases that make inert treatments seem to work Mar 20 Ott 2009 - 9:00|| |
In press (1999). Prepared for a special issue of Scientific Review of Alternative Medicine
Social and judgmental biases that make inert treatments seem to work.
Barry L. Beyerstein
Brain-Behaviour Laboratory, Department of Psychology,
Simon Fraser University, Burnaby, British Columbia, V5A 1S6 Canada
What we call public opinion is generally public sentiment.
If only ignorant and gullible people accepted farfetched ideas, little else would be needed to explain the abundance of folly in modern society. But, as James Alcock discusses elsewhere in this issue of SRAM, many people who are neither foolish nor ill-educated still cling fervently to beliefs that fly in the face of well-established research. Trust in the further reaches of complementary and alternative medicine (CAM) is a case in point. Paradoxically, surveys find that users of unscientific treatments tend to have slightly more, rather than less, formal education, compared to non-users.1 How are we to account for the fact that college graduates, and even some physicians, can accept therapeutic touch, iridology, ear candling, and homeopathy? Experts in the psychology of human error have long been aware that even highly trained experts are easily misled when they rely on personal experience and informal decision rules to infer the causes of complex events.2, 3, 4, 5 This is especially true if these conclusions concern beliefs to which they have an emotional, doctrinal, or monetary attachment. Indeed, it was the realization that shortcomings of perception, reasoning, and memory will often lead us to comforting rather than true conclusions that led the pioneers of modern science to substitute controlled, interpersonal observations and formal logic for the anecdotes and surmise that can so easily lead us astray. This lesson seems to have been largely lost on proponents of CAM. Some, such as Andrew Weil, reject it explicitly, advocating instead what he calls “stoned thinking,” a melange of mystical intuition and emotional satisfaction, for deciding which therapies are valid.6
CAM remains, for the most part, “alternative” because its practitioners depend on subjective reckoning and user testimonials rather than scientific research to support what they do. They remain outside the scientific fold because most of their hypothesized mechanisms contradict well-established principles of biology, chemistry or physics. If CAM proponents could produce acceptable evidence to back up their methods, they would no longer be alternative-they would be absorbed by mainstream medicine. It is my purpose in this article to draw attention to a number of social, psychological, and cognitive factors that can convince honest, intelligent, and well-educated people that scientifically-discredited treatments have merit.
Those who sell therapies of any kind have an obligation to prove, first, that their products are safe and, second, that they are effective. The latter is often the more difficult task because there are many subtle ways that honest and intelligent people (both patients and therapists) can be led to think that a treatment has cured someone when it has not. This is true whether we are assessing new treatments in scientific medicine, old nostrums in folk medicine, fringe practices in CAM, or the frankly magical panaceas of faith healers.
To distinguish treatment-induced changes in some underlying pathology from various kinds of symptomatic relief that might follow any sort of intervention, there has evolved a set of objective procedures for testing the effectiveness of putative remedies. It is reliance on these procedures that distinguishes so-called “evidence based medicine” from all the rest. Unless a ritual, technique, drug, or surgical procedure can be shown to have met these logical and evidential requirements, it is ethically questionable to offer it to the public, except on an admittedly experimental basis-especially if money is to change hands. Since most “alternative,” “complementary,” or “integrative” therapies lack this kind of support, one must ask why so many otherwise savvy consumers-many of whom would not purchase a toaster without turning to Consumer Reports for unbiased ratings from financially disinterested experts-trustingly shell out considerable sums for unproven, possibly dangerous, health products. We must also wonder why claims of alternative practitioners should remain so refractory to contrary data that are so readily available.
So, if an unorthodox therapy:
a. is implausible on a priori grounds (because its implied mechanisms or putative effects contradict well-established laws, principles, or empirical findings in physics, chemistry, or biology);
b. lacks a scientifically-acceptable rationale of its own;
c. has insufficient supporting evidence derived from adequately controlled outcome research;
d. has failed in well-controlled clinical studies done by impartial evaluators and has been unable to rule out competing explanations for why it might seem to work in uncontrolled settings; and
e. should seem improbable, even to the lay person, on “common sense” grounds,
why would so many well-educated people continue to sell and purchase such a treatment?
Users of unscientific treatments fall broadly into one of two camps. Once a user of either stripe decides to try an unconventional treatment, and believes that his or her personal experience alone is adequate to decide if it has worked or not, the judgmental biases and errors discussed below have a strong tendency to make even the most worthless interventions seem valid. As Alcock points out in his article in this issue, users of the first type try unconventional therapies because they assume, erroneously, that someone else has put them to the test. I.e., they place misplaced trust in the usual authorities on whom they rely. They see an uncritical news item, receive a testimonial from a friend, or see a dubious product displayed alongside the proven ones in their local pharmacy. They may also overgeneralize from the occasional news report of an “alternative” treatment that has actually passed scientific scrutiny and been adopted by orthodox medicine.
The other sort of user chooses his or her alternative treatments out of a broader philosophical commitment. For users who choose CAM on ideological grounds, their fondness for these practices is rooted in a much larger network of social and metaphysical assumptions. Needless to say, their cosmological outlook differs substantially from the rationalist-empiricist worldview that underlies scientific biomedicine. Because these adversaries enter the fray with so few shared axioms and rules of evidence, it is not surprising that a consensus is rarely reached. Proponents of CAM disagree with their detractors, not only about the basic constituents of the universe and the nature of the forces that govern them, but also, at the epistemological level-i.e., they cannot even agree about what are valid methods for settling such disputes.7 Health being such a basic human concern, it is to be expected that differing opinions about the causes and remedies for disease would form a integral part of these two incommensurate worldviews-one objective, materialistic and mechanistic, the other subjective, animistic and morally-driven. Because our views on health and disease are so enmeshed with our beliefs about the nature and meaning of life itself, not to mention the underpinnings of our moral precepts and our fundamental conceptions of reality, to attack someone’s belief in unorthodox healing is to threaten this entire, mutually-supportive system of bedrock beliefs. Not surprisingly, such attacks will be resisted with strong emotion.
The ability to defend one’s basic worldview is abetted by a number of cognitive biases that filter and distort contrary information. I shall return to these psychological processes that incline supporters to misconstrue their experiences to support their belief in CAM. But first let us examine the cultural milieu that has fostered a widespread desire to espouse such practices.
SOCIAL AND CULTURAL REASONS FOR THE
POPULARITY OF UNPROVEN THERAPIES.
As the 21st century approaches, several social trends have coalesced that enhance the popularity of CAM, in spite of (and to some degree, because of) its rejection by mainstream science. Today’s resurgence of folk medicine can be traced, in part, to nostalgic holdovers from the neo-romantic search for simplicity and spirituality that permeated the “counterculture” that attracted so many youthful converts during the 1960’s and’70’s.8 The aging flower children of the ‘60's and ‘70's now form the backbone of the “New Age” movement wherein unorthodox healing forms a central thrust.9 Many of the “baby boomers” who spearheaded the earlier movement now find that CAM satisfies the mystical longings, desire for simpler times, and naive trust in the beneficence of “Nature” they absorbed during those tumultuous times. CAM also resonates with that era’s mix of iconoclasm, reliance on feeling over reason, mistrust of science, and promotion of consumer advocacy. Let us examine how some of these features have promoted belief in non-scientific medicine among its clientele.
1. The low level of scientific literacy among the public at large.
Surveys consistently report that, despite our overwhelming dependence on technology for our safety, nutrition, health, shelter, transportation, entertainment, and economic well-being, the average citizen of the industrialized world is shockingly ignorant when it comes to even the rudiments of science.10, 11 In a recent survey, only 52% of Canadians who were polled could say how long it takes the earth to orbit the sun! These days, it is quite possible to make it through college and even graduate school with virtually no exposure to science courses at all. Consequently, most people lack the basic knowledge and critical thinking skills to make an informed choice when they must decide whether a highly-touted healthcare product is a sensible buy or not. When consumers haven’t the foggiest idea how bacteria, viruses, prions, oncogenes, carcinogens, and environmental toxins wreak havoc on bodily tissues, shark cartilage, healing crystals, and pulverized tiger penis seem no more magical than the latest breakthrough from the biochemistry lab.
2. An increase in anti-intellectualism and anti-scientific attitudes riding on the coattails of New Age mysticism.
As a major plank in the New Age platform, CAM is permeated with the movement’s magical and subjective view of the universe, epitomized in its catchphrase, “You create your own reality”.9 In advocating emotional over empirical and logical criteria for deciding what to believe, New Age medical gurus such as Andrew Weil and Depak Chopra have fostered the attitude that “anything goes”.6 Even in elite academic institutions, there are strong proponents of the notion that objectivity is an illusion and how you feel about something determines its truth value.12, 13 To the extent that this has led many people to devalue the need for empirical verification in general, it has enlarged the potential following for those who sell magical and pseudoscientific health products .14, 15, 16, 17, 18
Mind-body dualism permeates New Age thought, not least of all in its alternative medicine wing. Ironically, though, it is the New Age supporters of CAM who accuse their scientific critics of being dualists.19, 20 However, it is the CAM afficionados who are the real dualists, as evidenced by their constant appeal to undetectable spiritual interveners in matters of health. They need this obfuscation in order to support the oft-heard canard that scientific medicine undervalues the effects of mental processes on health.7 This confusion this has spread in the public mind has paved the way for a resurgence of many variants of “the mind cure” so popular in past centuries; i.e., the belief that the real causes and cures for almost all disease lie in the mind, conceived by New Agers as coextensive with the immaterial soul.21 It is easy to understand the appeal of such beliefs among those who have elevated wishful thinking to a virtue. Wouldn’t it be nice if laughter and thinking optimistic thoughts would keep us healthy, prayer could rid us of diseases, or imagining little Samurais in the bloodstream attacking malignant cells would purge the body of cancer? Admittedly, there is evidence for psychological effects on one’s health, but the size of these effects has been blown out of all proportion by CAM promoters such as Herbert Benson.22 Several good critiques of the errors, experimental confounds and artifacts that permeate the literature on spiritual beliefs and health have appeared recently.23, 24, 25
A related and troubling supposition common to New Age health propaganda is that one’s moral standing can alter how forces in the natural world will affect us. In accepting this anthropocentric and animistic worldview, alternative healers are reverting to the pre-scientific notion that health and disease are tied to one’s personal worthiness, rather than to naturalistic causes. This has fostered the return of an endless variety of long since discredited practices that purport to make patients “deserve wellness,” rather than attacking the cellular bases of their diseases. Often, this merely leads to blaming the victim, for, implicitly, the patient must have done something despicable to “deserve” his or her affliction. And if the treatment fails, as it so often does, sufferers feel worse yet, for they must have been undeserving of a cure.
3. Vigorous marketing of extravagant claims by the “alternative” medical community.
Strong profit motives have led alternative healers to promote themselves through aggressive marketing and intense legislative lobbying.26 Routinely, promises are made that no ethical scientifically-trained practitioner could or would make. In addition, new diseases of dubious scientific status are invented-and treated.7, 27 Unfortunately, facing this slick promotional barrage is a citizenry poorly equipped, in general, with the skills or information for evaluating this hyperbole.11
4. Inadequate media scrutiny and attacking critics.
With some notable exceptions, the electronic and print media have tended to give CAM a free ride. The enthusiastic claims of the “alternatives,” typically supported by nothing but anecdotes and testimonials, make uplifting stories that are all too rarely challenged by journalists who know that audience satisfaction cashes out in the rush for ratings.
Another disturbing trend that has had a chilling effect on some who would criticize unscientific treatments stems from the fact that many of these procedures have been imported from non-European cultures and championed by female practitioners. A rhetorical tactic that allows self-
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promoters to sidestep the substance of fair criticisms is to hurl accusations of racism and sexism at anyone who dares to express doubts. E.g., some practices, such as “therapeutic touch,” that have been rejected by scientific medicine are being embraced by an increasing number of nursing schools. Because these are still predominantly female institutions, looking to enhance the autonomy, scope, and earning power of their graduates by monopolizing new, sometimes dubious, spheres of practice, critics of practices salvaged from the trashbin of scientific medicine often find themselves accused of sexism. Similarly, when a colleague and I published a critique of several unsupported aspects of Traditional Chinese Medicine (TCM)26, we were accused of cultural insensitivity and racism.28 We were chided for presuming to criticise the effectiveness of TCM when we were not steeped in the philosophy of the culture that spawned it. To accept this absurd argument would be to agree that no one but a gourmet cook could tell when she’s been served a bad meal. My rejoinder is, of course, that the truly racist and sexist attitude would be to hold empirically testable claims from other cultures or female proponents to a lower standard of proof than any others-this would amount to an assertion that their defenders are intellectually inferior. In the final analysis, appeals such as these to “other ways of knowing” amount to nothing more than tacit admission that these treatments cannot pass the standard procedures for vetting would-be therapies. Fortunately, since good science is practised in the same way by all ethnic groups and both sexes, there are many strong opponents from within these communities who find ancient, unproven practices just as dubious as do white male critics.29, 30
5. Increasing social malaise and mistrust of traditional authority figures-the anti-doctor backlash.
Growing disillusionment with the conventional wisdom and apprehensiveness about the future has fostered a certain crankiness in Western societies. This has intensified the willingness of many people to believe that our social, economic, and political shortcomings must be due to active connivance on the part of powerful, secretive cabals, rather than the cumulative mistakes of well-intentioned planners muddling through as best they can. Consequently, there is a growing desire to espouse grand conspiracy theories and to attack the institutions or interest groups that are suspected of plotting against the common good.31 In this climate of suspicion, government is increasingly seen as a party to the plot and the scientific and medical professions have also begun to bear the brunt of what Richard Hofstadter identified decades ago as the “paranoid streak” in American politics.
These conspiratorial musings have coincided with two other, not entirely unjustified, undercurrents to promote an anti-doctor backlash that CAM proponents have been quick to exploit. One is a sense of disappointment arising from the failure of certain overly-optimistic predictions of medical breakthroughs to materialize. The other is the realization that medicine, as a self-regulating profession, has not always held the public good at the top of its political agenda.32 This has added fuel to the social envy many people feel regarding the status, political clout, and earning power of the medical profession. As Ambrose Bierce once wrote, a physician is “one upon whom we set our hopes when ill and our dogs when well.”
The inability of many people to separate in their minds certain self-serving actions of medical associations in the economic/political arena from the debate over whether scientific medicine’s treatments are genuinely better than those of CAM has been a boon to the latter. In this fractious climate, the “alternatives” have also benefitted by painting themselves as defenders of the democratic ideal of “choice.” This would be commendable if consumers had the wherewithal to make an informed choice.
6. Dislike of the delivery methods of scientific biomedicine.
There exists a widespread but exaggerated fear that modern medicine has become excessively technocratic, bureaucratic, and impersonal. The narrowing of medical specialties, the need to maximize the cost-efficient utilization of expensive facilities, the advent of third-party payment and managed care, and the staggering workloads of medical personnel have led some patients to long nostalgically for the simpler days of the kindly country doctor with ample time and a soothing bedside manner. They tend to forget, however, that this was often all a doctor of that era had to offer. Nonetheless, medical schools are coming to a renewed appreciation for the tangible benefits of interpersonal relationships in healthcare delivery and have begun, in their admission procedures, to look more closely at applicants’ social skills in addition to their academic and technical excellence. The “alternatives” can rightly claim some credit for moving this up the agenda.
7. Safety and Side Effects.
A quaint bit of romanticism that draws converts to New Age, “holistic” healthcare is the assertion that “natural” remedies are necessarily safer, gentler, and more efficacious, than those of technological origin.7 One hears frequently, for instance, the ludicrous claim that herbal concoctions have no side effects. If the ingredients in a natural product are potent enough to affect one’s physiology in an advantageous way, they are certainly powerful enough to cause side effects as well. To say otherwise is to admit that one is administering an inert substance. In fact, some popular herbal concoctions are far from benign-a growing number of reports show allergic, toxic, even lethal, reactions among users of certain herbal remedies.30, 33,34, 35, 36, 37 Numerous examples of mislabeling and serious contaminations of popular herbal products have also been reported. As usage rates rise, interactions with prescribed medications are also becoming more prevalent, since patients rarely know what is in the concoctions they are self-prescribing or receiving from herbalist. This danger is compounded by the fact that users are often reluctant to admit such indulgences to their physicians. Public awareness of the possible adverse effects of herbal concoctions has tended to be sparse because, unlike prescription drugs, there is no requirement that ill effects of supplements and herbal medications be reported to central registries. Unfortunately, under current U.S. law, the reverse onus exists, requiring the government to show that a supplement or herb is unsafe before manufacturers and vendors can be forced to remove it from the market.37
Among purveyors and users of herbs and supplements, even when adverse effects do occur, they are likely to be ignored or attributed to other causes. That is because there is a touching belief in these quarters that beneficent Nature would never pull such dirty tricks. In the same naive fashion, health food devotees staunchly maintain that “natural” Vitamin C from plants is more effective than the identical molecule manufactured in the chemistry lab, an idea equivalent to saying that bricks recycled from a cathedral will produce a better house than bricks salvaged from a brothel. Boosters of “natural” products should also be reminded that tobacco, bacteria, viruses and prions are quite natural too, and that some of the most deadly poisons known (e.g., belladonna, strychnine, cytisine, aflatoxin, and mycotoxins) are are found in wholly natural plants. On the other hand, over a third of all drugs routinely used in scientific biomedicine were derived from herbal sources, including many of the most widely used drugs in cancer chemotherapy.37 The difference, of course, is that the active ingredients in these products, though originally from nature, are now known and have passed rigorous tests of safety and efficacy. This allows their purity and dosages to be accurately controlled, something than cannot be said of herbalists’ products whose active ingredients have been shown in lab assays to vary, in different samples, by a factor of as much as 10,000.37
Possible adverse consequences of other branches of alternative medicine have also been slow in being compiled, for similar socio-political reasons.7 Fortunately, the Internet is beginning to provide some valuable sources of such cautionary information, though warnings are in danger of being swamped by the torrent of hype and self-promotion on the net. A number of websites containing scientifically reliable data about herbal remedies and supplements are listed in reference number 37, below. Similar listings regarding other aspects of CAM can be found at “www:quackwatch.com” and “www.healthwatcher.net”, the websites maintained, respectively, by Drs. Stephen Barrett and Terry Polevoy. Dr. George Lundberg, the new editor of the online medical journal, Medscape, (www.medscape.com) has also announced that this electronic journal will be expanding its coverage of the possible harms of alternative treatments.
PSYCHOLOGICAL REASONS FOR THE POPULARITY
OF ALTERNATIVE THERAPIES
Psychologists have long been aware that people generally strive to make their attitudes, beliefs, knowledge, and behaviors conform to a harmonious whole. When disquieting information intrudes and cannot easily be ignored, it is fascinating to observe the extent to which we can distort or sequester it to reduce the inevitable friction. It is to these mental gyrations that we now turn.
1. The Will to Believe.
We all exhibit a willingness to endorse comforting beliefs and to accept, uncritically, information that reinforces our core attitudes and self-esteem.40 Since it would be nice if many of the hopeful shibboleths of alternative medicine were true, it is not surprising that they are often seized upon with little demand for proof. Once adopted, such beliefs are remarkably resistant to contrary arguments. As Zusne and Jones41 have emphasized, magical and pseudoscientific beliefs are typically parts of more fundamental systems of belief, ones that define to the holder’s basic concept of reality. Anything this central to one’s cosmology and social outlook will be defended strongly, by filtering or misconstruing contrary input if need be.42
2. Logical Errors and Lack of a Control Group.
One of the most prevalent pitfalls in everyday decision-making is to mistake correlation for causation. Logicians refer to this error as the Post Hoc, Ergo Propter Hoc fallacy (“After this, therefore because of this”). It is the basis of most superstitious beliefs, including many of the underpinnings of CAM. We all have a tendency to assume that things which occur together must be causally connected although, obviously, they needn’t be. E.g., there is a high correlation between the consumption of diet soft drinks and obesity. Does this mean that artificial sweeteners cause people to become overweight?
When we count on personal experience to test the worth of medical treatments, we necessarily do so in situations where we lack complete information. The task of determining cause and effect is made even more difficult in the case of healthcare by the fact that many relevant factors are varying simultaneously-something casual observation cannot accurately track. This, plus the fact that the outcome of any single case could always have been a fluke, makes it virtually impossible to isolate actual causes when we base our decisions on personal experience in a single instance. Personal endorsements supply the bulk of the support for unorthodox health products, but they are an extremely weak currency because of what Gilovich43 has called the “Compared to What?” problem. Without comparison to a similar group of sufferers, treated identically except that the allegedly curative element is withheld, any individual recipient can never know whether he or she would have recovered just as well without the vaunted treatment. Probably the single biggest failing of the CAM movement is its inability to see the need for the simple control group.
3. Judgmental Shortcomings.
Those who cast doubt on fringe treatments are frequently dismissed with the rejoinder, “I don’t care what your research studies say; I know it worked for me.” It is well established, however, that this kind of intuitive judgement often leads to seriously flawed conclusions.4, 44 Unfortunately, the typical purveyor and purchaser of unproven therapies is insufficiently aware of the many perceptual and cognitive biases that can lead to faulty decisions when we depend on personal experience to decide what has caused a disease or whether a therapy “has worked” or not. Redelmeier and Tversky45 showed how people are prone to perceive illusory correlations in random sequences of events. They then demonstrated how these intuitive feelings of association have led to the false but widespread belief that arthritis pain is influenced by the weather. Proponents of CAM, who take many folk beliefs like this at face value, seem oblivious to how easy it is to be misled by uncontrolled observations and misrecollections such as these.
The pioneers of the scientific revolution were aware of the large potential for error when informal reasoning joins forces with our penchant for jumping to congenial conclusions. By systematizing observations, studying large groups rather than a few isolated individuals, instituting control groups, and trying to eliminate confounding variables, these innovative thinkerss hoped to reduce the impact of the frailties of reasoning that lead to false beliefs about how the world works. None of these safeguards exists when we base our decisions merely on a few satisfied customers’ personal anecdotes-unfortunately, these stories are the “alternative” practitioner’s stock in trade. Psychologists interested in judgmental biases have repeatedly demonstrated that human inference is especially vulnerable in complex situations, such as that of evaluating therapeutic outcomes, which contain a mix of interacting variables and a number of strong social pressures. Add a pecuniary interest in a particular outcome, and the scope for self-delusion is immense.
The job of distinguishing real from spurious causes in everyday situations requires not only controlled observations, but also systematized abstractions from large bodies of data. Dean and his colleagues46 showed, using examples from another popular pseudoscience, handwriting analysis, that without large, sophisticated databases and statistical aids, human cognitive abilities are simply not up to the task of sifting valid relationships out of huge masses of interacting data. Similar difficulties would have confronted the elders of pre-scientific medicine, and for that reason, we cannot accept their, or their descendants’, anecdotal reports as sufficient support for their methods.
Noticing interesting correlations in one’s surroundings is a reasonable starting point for a systematic, controlled analysis that could actually reveal the underlying causal structure that might be exploited. Observing such a correlation, however, should never be the end point in a search for a relationship that could eventually be put to therapeutic use.
In defending their enterprise, proponents of CAM generally ignore these cautions and encourage instead another unfortunate human tendency, that of placing more faith in personal experience and intuition than on controlled, statistical studies. The “alternatives” encourage this in their followers by calling it independence of thought, which, of course, can sometimes be a good thing. They should know, however, that it can also lead the appraiser astray in many situations in which personal experience is not a good guide to the actual state of affairs.
4. Psychological distortion of reality.
Distortion of perceived reality in the service of strong belief is a common occurrence (see Alcock40 and his article in this issue of SRAM). Even when they derive no objective benefits, devotees who have a strong psychological investment in alternative medicine can convince themselves that they have been helped. According to cognitive dissonance theory47, when new information contradicts existing attitudes, feelings, or knowledge, mental distress is produced. We tend to alleviate this mental discord by reinterpreting, i.e., distorting, the offending input. To have received no relief after committing time, money, and “face” to an alternate course of treatment (and most likely to the cosmology of which it is a part) would be likely to create this kind of internal dissonance. Because it would be too disconcerting, psychologically, to admit to one’s self or to others that it had all been a waste, there would be strong psychological pressure to find some redeeming value in the treatment.
5. Self-serving biases and demand characteristics.
There are many self-serving biases that help maintain self-esteem and promote harmonious social functioning42. None of us wishes to admit to ourselves or others that we believe foolish things or that we are accepting people’s trust and money under false pretenses. Because these core beliefs in our own virtue and intelligence tend to be vigorously defended-by warping perception and memory if need be-fringe practitioners, as well as their clients, are prone to misinterpret cues and remember things as they wish they had happened, rather than as they really occurred. In this way, therapists who don’t keep good records and apply proper statistics (as is generally the case in CAM) can be selective in what they recall, thereby overestimating their apparent success rates while ignoring, downplaying, or explaining away their failures.
An illusory feeling that one’s symptoms have improved could also be due to a number of so-called “demand characteristics” found in any therapeutic setting. In all societies there exists a “norm of reciprocity,” an implicit rule that obliges people to respond in kind when someone does them a good turn. Therapists, for the most part, sincerely believe they are helping their patients and it is only natural that patients would want to please them in return. Without clients necessarily realizing it, such obligations (in the form of implicit social demands) are sufficient to inflate their perception of how much benefit they have received. Thus controls for this kind of compliance effect must also be built into properly conducted clinical trials.48 Again, proponents of CAM downplay the need for such controls, possibly a form of self-delusion in itself.
WHY MIGHT THERAPISTS AND THEIR CLIENTS WHO RELY ON
ANECDOTAL EVIDENCE AND UNCONTROLLED OBSERVATIONS ERRONEOUSLY CONCLUDE THAT INERT THERAPIES WORK?
Although the terms “disease” and “illness” are often used interchangeably, for present purposes, it is worth distinguishing between the two. In what follows, I shall use “disease” to refer to a pathological state of the organism arising from infection, tissue degeneration, trauma, toxic exposure, carcinogenesis, etc. By the term “illness” I will mean the feelings of malaise, pain, disorientation, dysfunctionality, or other subjective complaints that might accompany a disease state. Our subjective reaction to the raw sensations we call symptoms is, like all other perceptions, a complex cognitive construction. As such, it is molded by factors such as beliefs, suggestions, expectations, demand characteristics, self-serving biases, and self-deception. The experience of illness is also affected (often unconsciously) by a host of social, monetary, and psychological payoffs that accrue to those admitted to the “sick role” by society’s gatekeepers (i.e., health professionals). For certain individuals, the privileges and benefits of the sick role are sufficient to perpetuate the experience of illness after a disease has healed, or even to create feelings of illness in the absence of disease.27, 49 Awareness of these dynamics can be quite minimal in the non-diseased patient who has learned, through subtle psychological mechanisms, to feel ill.. A conscious intent to deceive is definitely not required
Unless we can tease apart the many factors that contribute to the perception of being ill, or being improved, personal testimonials offer no basis on which to judge whether a putative therapy has, in fact, cured anyone’s disease. That is why blinded placebo-controlled clinical trials, with objective physical measures if possible, are absolutely essential in evaluating therapies of any kind. Bearing this in mind, then, why might someone mistakenly believe that they had been helped by an inert treatment?
1. The disease may have run its natural course.
Many diseases respond well to “the tincture of time.” In other words, they are self-limiting. Providing the condition is not chronic or fatal, the body’s own recuperative processes will restore the sufferer to health. Thus, before the curative powers of a putative therapy can be acknowledged, its proponents must show that the percentage of patients who improve following treatment exceeds the proportion expected to recover without any intervention at all (or that they recover reliably faster than if left untreated). Unless an unconventional therapist releases detailed records of successes and failures over a sufficiently large number of patients with the same complaint, she cannot claim to have exceeded the norms for unaided recovery. As noted above, without an adequate control group, any given practitioner will never know how his clients would have fared without his ministrations.
To be fair, the “alternatives” are correct that many effective treatments in conventional medicine are also aimed at symptomatic relief or strengthening the body’s own recuperative mechanisms, rather than attacking the disease process itself. It’s just that proponents of CAM offer little convincing evidence that their own unique efforts along these lines are particularly effective. Nonetheless, the “alternatives” can take some satisfaction in the fact that the debate they have provoked has spurred conventional biomedical researchers to seek more effective ways of stimulating natural recovery processes, such as enhancing certain immune reactions. Unfortunately, their disinterest in research means that the “alternatives” will contribute little to the understanding that will eventually lead to therapeutic improvements.
2. Many diseases are cyclical.
Arthritis, multiple sclerosis, allergies, and gastrointestinal complaints are examples of diseases that normally “have their ups and downs.” Not surprisingly, sufferers tend to seek therapy during the downturn of any given cycle. In this way, a bogus treatment will have repeated opportunities to coincide with upturns that would have happened anyway. Again, in the absence of appropriate control groups, consumers and vendors alike are prone to misinterpret improvement due to normal cyclical variation as a valid therapeutic effect.
3. Spontaneous remission.
Any anecdotally reported cure could have been due to a rare but possible “spontaneous remission.” Even with certain cancers that are nearly always lethal, tumors occasionally disappear without further treatment. One experienced oncologist reports that he has seen 12 such events in about 6000 cases he has treated50. Alternative therapists can receive unearned acclaim for such remissions because many desperate patients turn to them out of a feeling that they have nothing left to lose. When the “alternatives” assert that they have snatched many hopeless individuals from death’s door, they rarely reveal what percentage of their apparently terminal clientele such happy exceptions represent. What is needed is statistical evidence that their “cure rates” exceed the known spontaneous remission rate and the placebo response rate (see below) for the conditions they treat.
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The exact mechanisms responsible for spontaneous remissions are not well understood at present, but much research is being devoted to revealing and possibly harnessing processes in the immune system or elsewhere that are responsible for these unexpected turnarounds. Some researchers think that spontaneous remissions are less the result of immune surveillance than due to the fact that certain biochemical reactions necessary for growth in malignant masses can, on occasion, reach a self-limiting stage before the accumulated tumor mass kills the patient. Whatever the mechanism, the documented existence of spontaneous remissions in a variety of diseases, in people who do not avail themselves of alternative treatments, means that an occasional dramatic, unexpected turnaround cannot be used to validate the power of prayer or a fringe therapy.
4. The placebo effect and the need for randomized, double blind assessments.
A major reason why bogus remedies are credited with subjective, and occasionally objective, improvements is the ubiquitous placebo effect18, 50, 51 (see also Jittler, Beyerstein, and Beyerstein, this issue of SRAM). The history of medicine is strewn with examples of what, with hindsight, seem like crackpot procedures that were once enthusiastically endorsed by physicians and patients alike.16, 52, 53 Misconceptions of this sort arise from the false assumption that a change in symptoms following a treatment must have been a specific consequence of that procedure. Through a combination of suggestion, belief, expectancy, cognitive reinterpretation, and attentional diversion, patients given biologically useless treatments can often experience measurable relief nonetheless. Some placebo responses produce actual changes in physical symptoms; others are subjective changes that make patients feel better although there has been no measurable change in their underlying pathology.
Through repeated contact with valid therapeutic procedures, we all develop, much like Pavlov’s dogs, conditioned responses in various physiological systems. Later, these responses can be triggered by the setting, rituals, paraphernalia, and verbal cues that signal the act of “being treated.” Among other things, placebos can cause release of the body’s own morphine-like pain killers, the endorphins18. Because these learned responses can be palliative, even when a treatment itself is irrelevant to the source of the complaint, it is necessary that putative therapies be tested against a placebo control group-i.e., similar patients who receive a sham treatment that resembles the “real” one, except that the suspected active ingredient is withheld.
It is essential that the patients in such tests be randomly assigned to their respective treatment groups. Otherwise, sicker or more compliant people could end up in one group or another, or people with harmful or helpful lifestyles or certain habits, industrial exposures, etc., could be disproportionately allocated. These group differences could produce effects that might be spuriously attributed to the experimental manipulation-something researchers call an “experimental confound”. Good examples of the mischief such confounds can wreak are discussed in a recent critique of studies purporting to show that various religious practices enhance health25. Indeed, practicing members of certain faiths do seem to enjoy certain medical benefits. The question, however, is whether faith itself is responsible, i.e., a benevolent deity looks out for the pious, or simply that observant believers also tend to smoke and drink less, engage in fewer risky activities, live in less toxic environments, enjoy better social support networks, come from certain ethnic backgrounds, and so on. And, of course, given that stress can have adverse health consequences, belief in a supernatural protector could be health-promoting via its ability to alleviate anxiety, regardless of whether the belief is true or not. Once again we see the perils of assuming that correlation implies causation.
In addition, adequately controlled research requires that all recipients must be “blind” with respect to whether they are receiving the active versus the placebo treatment. Because the power of what psychologists call expectancy and compliance effects is so strong, the therapists must also be blind as to the group membership of individual patients 48. Hence the term “double blind”-the gold standard of outcome research. Such precautions are required because barely perceptible cues, unintentionally conveyed by treatment providers who are not blinded, can bias test results. Likewise, those who assess the treatment’s effects must also be blind, for there is a large literature on “experimenter bias” showing that honest and well-trained professionals can unconsciously “read in” the outcomes they expect when they attempt to assess complex events54, 55. If one’s professional advancement or net worth depends on validation of a putative treatment, there is all the more need for blind assessments. Ideally, the end points being measured will be objective, and if the measurements can be mechanized and automated to reduce the effects of observer subjectivity, so much the better. It is odd that CAM supporters who would not think much of a wine tasting that failed to obscure the labels on the bottles, still downplay the need for blinded assessments when it comes to their own stock in trade.
When the clinical trial is completed, the blinds can then be broken to allow statistical comparison of active, placebo, and no-treatment groups. Only if the improvements observed in the active treatment group exceed those in the other two groups by a statistically significant amount can the therapy claim legitimacy.
Defenders of CAM often complain that conventional medicine itself continues to use many treatments that have not been adequately vetted in placebo-controlled, double-blind trials. This may be so in some instances, but the percentage of such holdovers is grossly exaggerated by the “alternatives”56. At any rate, this does nothing to enhance the credibility of CAM, for merely arguing that “they’re as bad as we are” offers no positive evidence in favor one’s own pet belief. The crucial difference between scientific biomedicine and alternative medicine is that the former is institutionally committed to finding empirical support for its treatments and eventually weeds out those that fail to pass muster. And, unlike the “alternatives,” biomedicine does not cling to procedures that contradict well-established principles in the basic sciences. Scientifically-based therapies change because new research accumulates; alternative medicine is mired in the past and changes rarely, if ever. This is because the latter has no serious commitment to testing its rationales and procedures under controlled conditions. Alternative medicine clings to the belief that its procedures must be valid because they have stood the test of time. But the longevity of racism, sexism, and the belief in demonic possession belies the assertion that ability to survive implies validity.
5. Some allegedly cured symptoms were probably psychosomatic to begin with.
The pioneering neurologist Joseph Babinski (1857-1932) coined the term “pithiatism” to refer to conditions he concluded were “caused by suggestion, cured by persuasion.” A constant difficulty in trying to measure therapeutic effectiveness is that there are many such complaints that can both arise from psychosocial distress and be alleviated by support and reassurance. At first glance, these symptoms (at various times called “psychosomatic,” “hysterical,” or “neurasthenic”) resemble those of recognized medical syndromes27, 57. Although there are many “secondary gains” (i.e., psychological, social, and economic payoffs) that accrue to those who slip into “the sick role” in this way, we need not accuse them of conscious malingering to point out that their symptoms are nonetheless maintained by subtle psychosocial processes49.
Alternative healers cater to these members of the “worried well” who are mistakenly convinced that they have organic diseases or morbidly fearful that they may lose their good health. Their complaints are instances of somatization, the tendency to express psychological concerns in a language of symptoms like those of organic diseases27, 58, 59. The “alternatives” offer comfort to these individuals who need to believe their symptoms have medical rather than psychological causes. Often with the aid of pseudoscientific diagnostic devices, fringe practitioners reinforce the somatizer’s conviction that the cold-hearted, narrow-minded medical establishment, who can find nothing physically amiss, is both incompetent and unfair in refusing to acknowledge a very real organic condition. A large proportion of those diagnosed with “chronic fatigue,” “environmental sensitivity syndrome,” irritable bowel syndrome, fibromyalgia, and post-traumatic stress disorders (not to mention many suing manufacturers because of the allegedly harmful effects of silicone breast implants61) look very much like classic somatizers59, 60. Similar dynamics seem to underlie reports of a more recent variant of what Stewart59 has called this family of “fashionable diseases,” i.e., “Gulf War Syndrome” 62.
If a patient’s symptoms were psychologically caused to begin with, he or she is likely to respond favorably to an acceptable blend of suggestion, reassurance, psychological support and reaffirmation. Often this is what (probably unknowingly) these patients are really seeking though their illness behavior. In rejecting this interpretation, CAM practitioners ask why, if the malaise is really of psychological origin, wouldn’t relief have been achieved already from any of the typically long list of abandoned conventional physicians? One answer is that the patient-doctor rapport necessary for such reassurance to be effective is likely to become strained as soon as the doctor says she cannot find any physical cause for the illness. If a physician even hints at a psychosomatic diagnosis, the relationship is likely to be poisoned irrevocably-for, sad to say, even in this supposedly enlightened age, psychological diagnoses still carry a social stigma for many. Thereafter, no amount of support and reassurance is likely to bridge the gap that has been opened. Curiously, though, when the alternative healer gives the sought-after physical diagnosis and then, in the next breath, reverts to the New Age line that all diseases are caused by mental/spiritual shortcomings, the same patient may well accept this about-face with enthusiasm. To the extent that alternative healers are often charismatic personalities, who are willing to spend extensive amounts of time reassuring their clients and catering to their existential concerns, this heightens their ability to capitalize on patient suggestibility 63 . It also stands to reason that suggestions arising from someone who buys into the patient’s metaphysical outlook might be more effective in countering psychosomatic complaints than those following from a or philosophically skeptical point of view.
When, through the role-governed rituals of “delivering treatment,” fringe therapists supply the reassurance, sense of belonging, and existential support that their clients are seeking, this is obviously worthwhile, but all this need not be foreign to scientific practitioners who have much more to offer besides. The downside is that catering to the desire for medical diagnoses for psychological complaints promotes pseudoscience and magical thinking while unduly inflating the success rates of medical quacks. Saddest of all, it perpetuates the prejudicial anachronism that there is something shameful or illegitimate about psychological problems.
6. Symptomatic relief versus cure.
Short of an outright cure, alleviating pain and discomfort is what sick people value most. Many allegedly curative treatments offered by alternative practitioners, while unable to affect the disease process itself, do make the illness more bearable, but for psychological reasons. Pain is one example. Much research shows that pain is partly a sensation like seeing or hearing and partly an emotion64, 65. Researchers have found repeatedly that anything that successfully reduces the emotional component of pain leaves the purely sensory portion surprisingly tolerable. Thus, suffering can often be reduced by psychological means, even if the underlying pathology is untouched. Anything that can allay anxiety, redirect attention, reduce arousal, foster a sense of control, or lead to cognitive re-interpretation of symptoms can alleviate the agony component of pain. Modern multi-disciplinary pain clinics put these strategies to good use every day 65. Whenever patients suffer less, this is all to the good, but we must be careful that purely symptomatic relief does not divert people from proven remedies for the underlying condition until it is too late for them to be effective.
7. Many consumers of alternative therapies hedge their bets.
In an attempt to appeal to a wider clientele, many unorthodox healers have begun to refer to themselves as “complementary” or “integrative,” rather than “alternative.” Instead of ministering primarily to the ideologically committed or those who have been told there is nothing more that conventional medicine can do for them, the “alternatives” have begun to advertise that they can enhance conventional biomedical treatments. They accept that orthodox practitioners can alleviate specific symptoms but contend that alternative medicine treats the real causes of disease -dubious dietary imbalances or environmental sensitivities, disrupted energy fields, or even unresolved conflicts from previous incarnations7. If improvement follows the combined delivery of “complementary” and scientifically-based treatments, the fringe practice often gets a disproportionate share of the credit.
8. Misdiagnosis (by self or by a physician).
In this era of media obsession with health, many people can be induced to think they suffer from diseases they do not have. When these healthy folk receive the oddly unwelcome news from orthodox physicians that they have no organic signs of disease, they often gravitate to alternative practitioners who can always find some kind of “energy imbalance,” nutritional deficit, or dubious “sensitivity” to treat. If “recovery” should follow, another convert is born.
Scientifically trained physicians do not claim infallibility, and a mistaken diagnosis, followed by a trip to a shrine, alternative healer, or herb counter can lead to a glowing testimonial for having cured a grave condition that never existed. Other times, the diagnosis may have been correct but the time course, which is inherently hard to predict, might have proved inaccurate. If a patient with a terminal condition undergoes alternative treatments and succumbs later than the conventional doctor predicted, the alternative procedure may receive credit for prolonging life when, in fact, the discrepancy was merely due to an unduly pessimistic prognosis. I.e., survival was longer than the expected norm, but within the range of normal statistical variation for the disease in question.
9. Derivative benefits.
Alternative healers often have forceful, charismatic personalities.62, 67, 68 To the extent that patients are swept up by the messianic aspects of CAM, a psychological uplift may ensue which can have both short and longer term spinoffs. If an enthusiastic, upbeat healer manages to elevate the patient’s mood and bolster his expectations, this enhanced optimism can lead to greater compliance with, and hence effectiveness of, any orthodox treatments he or she may also be receiving. This expectant attitude can also motivate people to improve their eating and sleeping habits and to exercise and socialize more. These changes, by themselves, could help speed natural recovery, or at the very least, make the recuperative interval easier to tolerate.
Psychological spinoffs of this kind can also reduce stress, which has been shown to have deleterious effects on the immune system69, 70. Removing this added burden may speed healing, even if it is not a specific effect of the therapy. As with purely symptomatic relief, this is far from a bad thing, unless it diverts the patient from more effective treatments, or the charges are exorbitant.
Before anyone should agree to accept an unconventional treatment, he or she should ask whether it has been subjected to the sort of controlled clinical trials described above. As should be obvious by now, personal endorsements are essentially worthless in deciding the value of any therapy. Instead, supporters of unorthodox therapies should be able to supply empirical evidence, based on large groups of patients and published in refereed scientific journals. Only by this process of peer-review can we be assured that the supporting research has been checked for the sources of error and bias described above. For example, reviewers look to see that the sample sizes were sufficiently large, the experimental design and statistical analyses were appropriate, and that obvious confounding variables were controlled for. The peer review process will determine that the participants were randomly assigned to treatment groups and that they were treated and assessed under double-blind conditions. It will also ensure that the condition of each patient was accurately assessed and documented before and after the intervention and, ideally, that the participants were followed up for a reasonable interval thereafter to gauge the duration of any beneficial changes. And, of course, because any single positive outcome could always have been a statistical fluke, replication by independent researchers with converging methodologies is the ultimate assurance. A single experimental result practically never settles an important scientific issue. It is the long-term track record that counts. And even with published papers that pass on the foregoing criteria, one should always look to see how large the reported treatment effects are. Beware of the “true but trivial effect.” There are many statistically-significant outcomes in research articles that are real but too small to be of any clinical use.
Any practitioner who cannot supply this kind of backing for his or her procedures is immediately suspect. One should be even more wary if, instead of peer-reviewed research, the “evidence” comes solely in the form of anecdotes, testimonials or self-published pamphlets or books. To be credible, supporting research articles should come from impartial journals in the appropriate scientific fields, rather than from journals owned by associations promoting the questionable practice, or from the “vanity press” which accepts virtually all submissions and charges the authors for publication of their work.
If the practitioner is ignorant of, or openly hostile to, mainstream science and cannot supply a reasonable scientific rationale for his methods, the would-be buyer should proceed with caution. If the “doctor’s” promotional patter is laced with allusions to spiritual forces or vital energies or to vague planes, vibrations, imbalances, and sensitivities, suspicions should also be aroused. Likewise, if the treatment provider claims secret ingredients or processes (especially if they are named after him- or herself), extols ancient wisdom and “other ways of knowing,” or claims to “treat the whole person, not diseases,” there is also good reason to question his or her legitimacy. If the therapist claims to be persecuted by the medical establishment, encourages political action on his or her behalf, and is prone to attack or even sue critics rather than answering their criticisms with valid research, alarm bells should begin to ring. Practitioners who sell their own supplements and other proprietary concoctions in their offices and stress the need for frequent return visits by healthy people, “in order to stay healthy,” are also a cause for concern. The presence of any pseudoscientific or conspiracy-laden literature in the waiting room ought to set a clear thinker looking for the nearest exit. And above all, if the promised results go well beyond those offered by conventional therapists, the probability is that one is dealing with a quack. In short, if it sounds too good to be true, it probably is.
When people become sick, any promise of a cure is especially beguiling. As a result, common sense and the willingness to demand evidence are easily supplanted by false hope. In this vulnerable state, the need for critical appraisal of treatment options is all the more necessary, rather than less. Potential clients of alternative therapists would do well to heed the admonition of St. Paul: “Test all things; hold fast to what is good” (I Th. 5:12). Those who still think they can afford to take a chance on the hawkers of untested remedies should bear in mind Goethe’s wise advice: “Nothing is more dangerous than active ignorance.”
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