Chiropractic: science and antiscience and pseudoscience side by side
Joseph C. Keating, Jr.
Now a century old, chiropractic is a continuing enigma partly because of its diverse intellectual and anti-intellectual traditions.
The chiropractic profession, now more than a century old, is a continuing enigma. Skeptical viewers of a videotape recently released by the Chiropractic Centennial Foundation, entitled “From Simple Beginnings,” will undoubtedly recognize the traditional dogma which proclaims that “chiropractic works” and does so by freeing nerves pinched between the bones of the spinal column, thereby relieving all or nearly all disease (or “disease”). Readers of George Magner’s critical book Chiropractic: The Victim’s Perspective (1995) will be similarly impressed by the unscientific, even irrational character of chiropractic revealed therein. Despite the volume’s “derogatory” tone (Albers 1996), the book is noteworthy for the thoroughness with which it documents chiropractic’s foibles. Religious overtones are also often found in the rhetoric of chiropractors (Fuller 1989; Keating 1989).
On the other hand, the recent guidelines issued by the federal Agency for Health Care Policy and Research (AHCPR) for patients with low-back pain endorsed chiropractors’ primary treatment method – spinal manipulative therapy. And a cost-effectiveness study of chiropractic services commissioned by the Ministry of Health for the Canadian province of Ontario strongly endorsed chiropractic management of low back pain (Manga et al. 1993). Federal funding for scientific research conducted at several chiropractic colleges has recently overwhelmed the historic barriers against chiropractic science, with research grants awarded to the Los Angeles College of Chiropractic, National College of Chiropractic, Palmer College of Chiropractic, and the Western States Chiropractic College.
What is one to think? Is chiropractic science or humbug? Little help in resolving this confusion comes from chiropractors themselves, who are still a long way from consensus about their identity, their scope of clinical practice, and their relationship to other health professions.(1) The standard humor within the profession offers a first principle: For every “DC” (doctor of chiropractic) there is an equal and opposite DC. Although chiropractors seem to be united in their belief that chiropractic is a science, they vary greatly among themselves in terms of their understanding of the nature and responsibilities of science.
After thirteen years of teaching and research at several chiropractic colleges, I can say with confidence that chiropractic is both science and antiscience. Yes, there is a meaningful science of chiropractic, but just as surely there is an antiscientific mindset and even a cult within chiropractic (for example, the cult of B. J. Palmer, son of the founder of chiropractic). Moreover, if University of Connecticut sociologist Walter Wardwell is correct (Wardwell 1992), the belief systems of a majority of DCs lie somewhere between these two poles: chiropractic as science versus chiropractic as unscientific, uncritical dogma and circus. Perhaps a consideration of the nature of science will aid in understanding how the chiropractic profession does and does not approximate the rigors of science.
Concepts of Science
Our culture offers many notions about the nature of science. For some, science means perfect or near perfect predictability and control. This image is reinforced by the spectacular success of some of the more visible technologies: space flight, computers, transplant surgery. However, if the accuracy of predictions were an essential characteristic of science, then fields like meteorology and vulcanology would have to relinquish any claim to scientific status, as would many areas of health care. Reduction of error is certainly a goal for any scientific discipline, but perhaps only mathematicians, who do not ordinarily trouble themselves with actual observations of the natural world, can claim to achieve the exactness suggested by this image of science. Some chiropractors deploy this notion of science (near perfect predictability) as an easily defeated “straw man” with which to refute the meaningfulness of medical science.
A Hollywood vision of science is sometimes implied by the criticism that chiropractic has produced no discoveries to rival those of Louis Pasteur or Jonas Salk. This concept involves the belief that science means dramatic breakthroughs in knowledge. The reality of most scientific research, however, is far less glamorous, though no less important. Moreover, if this criterion of “science” were applied uniformly, many disciplines (for example, podiatry, psychology, physical therapy) would not measure up. Yet these fields are generally considered “scientific,” and genuine scientific research is conducted in all of them. Nor can it be said that the chiropractic profession has not contributed, however minimally, to the scientific database bearing on manipulation and musculo-skeletal disorders.
The chiropractic profession is sometimes portrayed as lying outside of science on the grounds that “the chiropractic theory” has never been proven and may have been disproven (e.g., Crelin 1973). These assertions imply that there is only one theory of chiropractic and that the legitimacy of a profession may stand or fall upon the validation of a single theory. Critics of chiropractic repeatedly point to the century-old hypothesis that diseases are caused by nerves that are pinched in the spaces between the bones of the spinal column, and suggest that this idea is bogus. They may be correct, but there are, in fact, many theories about spinal lesions (Gatterman 1995; Leach 1994), or what chiropractors refer to as subluxations. (Osteopathic theorists seem to be referring to similar presumed clinical entities, which they name somatic dysfunctions or osteopathic lesions.) The problem with most of these theories is not that they have been disproven, but that they have not been adequately tested; we don’t yet know which is chaff and which is wheat. We have reason to believe that spinal manipulation reduces low back pain, but whether this is due to removing subluxations or increasing circulating endorphins, or other factors, or some combination thereof, is not yet known. To further confuse the issues, there probably are many musculo-skeletal problems with symptoms that mimic organic (internal) disease (Nansel and Szlazak 1995). It’s not hard to imagine that some sincere but naive chiropractors have accepted incorrect medical diagnoses of internal disorders (or incorrect reports of diagnoses from patients), and when symptoms have cleared up following manipulation, the DCs believe they have cured serious internal disorders.
Chiropractors certainly have been remiss in failing to adequately study the variety of subluxation theories they have proposed, but this does not detract from the research that has been conducted. Nor does this shortfall in hard scientific data for subluxation disallow the meaningfulness of a science of chiropractic. We would not reject psychiatry as science on the grounds that Freud’s theories of anxiety, repression, or the unconscious have not been adequately tested. We do not reject the meaningfulness of a science of medicine on the grounds that most medical procedures have not been experimentally validated. Nor should we apply such standards to chiropractic as a determiner of its scientific viability.
An operational definition of chiropractic as science has been offered (Keating and Mootz 1987) that suggests the scientific status (or lack thereof) of chiropractic (or of any profession) can be recognized by the presence or absence of the activities of science. In other words, chiropractic may be considered science if chiropractors engage in the work of scientists. Among the activities common to all sciences are: 1) systematic observation and description of natural phenomena, 2) the making and testing of predictions (hypotheses), 3) experimentation (controlled analyses of cause/effect relationships among natural phenomena), and 4) publication of findings derived from these activities in scholarly journals where theories and data may be subjected to critical review by any interested party. By these criteria, the existence of a science of chiropractic seems unmistakable, as evidenced in the pages of several periodicals (see Table 1). Although the volume of research in chiropractic remains minimal, there is legitimate scientific activity, the scientists “right stuff.”
Yet another way of judging the meaningfulness of chiropractic as science is to consider the attitudes held by chiropractors concerning the acquisition of new knowledge. These attitudes, also called epistemologies, are quite diverse among chiropractors, but a particular, “scientific” attitude is reasonably well established among clinical scholars and investigators in other fields, and can be found among a subset of chiropractors.
Epistemologies in Chiropractic
Epistemology is the branch of philosophy that deals with the nature of knowledge, or how we know whatever we think we [TABULAR DATA FOR TABLE 1 OMITTED] know. With respect to health care, epistemology addresses questions about how we may learn about health and illness (e.g., basic science), about how we may determine the validity of theories of treatment and prevention, and about the effectiveness of clinical procedures for restoring and maintaining health (e.g., clinical science). At the practical level of the health care practitioner, epistemology deals with questions such as which method(s) of healing will help which patients with which problems under what circumstances, and how we can make such determinations.
Throughout human history healers have relied, implicitly or explicitly, upon a variety of epistemologies in choosing their methods. Among the most common and familiar have been the various dogmas derived from or incorporating such strategies as spiritual inspiration, unchallenged precedent, casual personal experience, rationalism, and the scientific method. Often the differences among these ways of knowing “what works” have been embedded in cultural variations, such as the mysticism of the Orient versus the skepticism and “natural philosophy” of Western science. In other cases several distinct epistemological strategies may be evident within a single profession and may serve to indicate a paradigm shift within the discipline. As an example of the latter, consider the evolution of Western medicine away from a purely descriptive science and toward an experimental orientation at the dawn of the twentieth century (e.g., Martin 1993, 1994). Ironically, as medicine moved away from the descriptive epistemology of nineteenth-century science, the emerging field of chiropractic adopted the old ways of knowing and perpetuated a nonexperimental, uncontrolled system of gaining new knowledge.
Frequently, these differences in epistemology are accompanied by variations in theoretical propositions and/or by disputes over therapeutic methods, such as was evident in the osteopathic profession during its early decades (Gevitz 1982). Typically, a tension among the members of the profession is in evidence and continues until the shift in philosophical orientation is more or less complete. Perhaps less frequently, a profession may be locked in a state of seemingly perpetual conflict over epistemological, theoretical, and practical (technical) issues. An example of this phenomenon is found among chiropractors, who have argued among themselves for decades about such fundamental issues as who they are, what they do, what they don’t do, the nature of science, and even the value of the scientific method (Keating et al. 1995). Members of the profession offer a wide variety of epistemological strategies for determining the effectiveness of the methods they use (see Table 2), all but one of which are antithetical to the wider scientific community. Although a few members of the profession have adopted a genuinely scientific attitude toward clinical practice, many (perhaps a majority of) chiropractors offer up a great deal of what might be considered the “wrong stuff” for a science.
Although individuals may employ any one or any combination of the epistemological strategies shown in Table 2, perhaps the most frequently encountered rationale for believing that “chiropractic works” involves a combination of uncritical rationalism and private, uncritical empiricism. A doctor will argue that chiropractic theory and practice are consistent with Gray’s Anatomy (which “proves that the nerve system controls all parts of the body”) and that s/he has seen repeated “proof” of effectiveness on a daily basis in her/his clinic. These assertions are often supplemented with a litany of anecdotes about “miracle” cases, by uncontrolled reports of clinical outcomes, or by incorrect or inflated assertions about research findings (e.g., Frigard 1994).
In recent years this combination of uncritical rationalism and uncritical empiricism has been bolstered by the proliferation of pseudoscience journals of chiropractic wherein poor quality research and exuberant overinterpretation of results masquerade as science and provide false confidence about the value of various chiropractic techniques. These periodicals expand on the uncritical attitudes and unproven claims for chiropractic that have long been made in the magazines published by the national membership societies of chiropractors in the United States. It is practically impossible to read any of the trade publications within chiropractic without encountering unsubstantiated claims.
Coexisting with the obvious and ubiquitous antiscientific and pseudoscientific reasoning and rhetoric in chiropractic (Skrabanek 1988) are the genuinely critical, skeptical attitudes of the still quite embryonic research community in this profession. The clinical science attitude (bottom of Table 2) has been growing slowly among DCs during the past two decades. Some see the 1975 conference on spinal manipulation sponsored by the National Institutes of Health (Goldstein 1975), which brought together chiropractors, osteopaths, medical doctors, and Ph.D. scientists, as the moment of birth for a genuine science of chiropractic (e.g., Gitelman 1984). Others would date the birth of chiropractic science to the first publication of the Journal of Manipulative & Physiological Therapeutics (JMPT) in 1978, or to JMPT’s first inclusion (in 1981) in the National Library of Medicine’s Index Medicus, or to the publication of the first randomized, placebo-controlled clinical trial of chiropractic adjusting (Waagen et al. 1986).
I prefer to date the birth of chiropractic science to a long since forgotten commentary in the JMPT entitled “Notes from the (Chiropractic College) Underground” (DeBoer 1983). In this thirteen-year-old article, Kenneth F. DeBoer, then an instructor in basic science at Palmer College in Davenport, Iowa, revealed the power of a scholarly journal to empower faculty at the chiropractic schools. DeBoer’s opinion piece demonstrated the faculty’s authority to challenge the status quo, to publicly address relevant, albeit sensitive, issues related to research, training, and skepticism at chiropractic colleges, and to produce “cultural change” within the chiropractic schools so as to increase research and professional standards. I view DeBoer’s paper as a rallying call for chiropractic scientists and scholars.
To further our understanding of chiropractic as simultaneous science, dogma, showmanship, and marketing, it may be well to look inside the chiropractic colleges: at their visible elements, their facades, and their undergrounds.
Skepticism and Chiropractic Education
Chiropractic colleges vary considerably in terms of the commitment their faculties and administrators make to critical reasoning, skepticism, science, and scholarship. At one end of the spectrum lies Life College (situated outside Atlanta), whose founding president, Sid Williams, D.C., is also a former president and former chairman of the board of the International Chiropractors’ Association. With a student body in excess of four thousand, Williams is proud of having built the world’s largest chiropractic institution. Although he speaks of the “science of chiropractic,” he is notorious for his antiscientific attitudes and unsubstantiated claims; examples of his rhetoric include (American Chiropractic Association 1994):
God spoke to me in very clear language on three different occasions during a five-month period telling me to commence this work.
These conspirators would convince us that the “scientific approach” to chiropractic is the only approach acceptable to the public community, the professionals, the legislatures.
To hell with the scientists. They haven’t proven a bumble bee can fly.
If you got an improved homeostasis, what damn difference does it make what diseases you’re gonna be encountering. The whole germ theory comes crashing down from its tower.
Rigor mortis is the only thing that we can’t help!
At the other end of the ideological continuum one finds schools such as the National College of Chiropractic (situated outside Chicago), the Los Angeles College of Chiropractic (LACC), and several others. Now celebrating its ninetieth year, the National College has been a leader in scientific and scholarly development within the profession. This commitment is particularly apparent in its founding of the JMPT, and more recently of the Journal of Chiropractic Humanities. Members of the LACC’s faculty and administration have been frequent contributors to the scientific literature and collaborators with the RAND Corporation in developing systematic, evidence-based guidelines for the practice of spinal manipulation [TABULAR DATA FOR TABLE 2 OMITTED] for specific health problems (e.g., Shekelle et al. 1991). The above-average commitment to scholarship and critical thinking of the LACC and the National College are further reflected in each school’s initiative in developing problem-based learning for chiropractic students. Skeptical eyebrows may be raised by some of the hypotheses entertained at these schools, but a closer examination will reveal that a healthy skepticism is also present.
Other chiropractic colleges represent various points between the philosophical poles represented by Life College versus National College and the LACC. Yet within all of these institutions may be found individuals (faculty, administrators, students) whose epistemologies and commitment to skeptical inquiry are at odds with their institutions. The writer suspects that all of the reasoning mechanisms listed in Table 2 can be found at any of the chiropractic schools.
There are multiple factors to account for the variety of antiscientific attitudes found at chiropractic institutions. Many of these ideologies are embedded within the historic battle between chiropractors and organized medicine (Keating and Mootz 1989). This diversity of epistemologies is partly attributable to the traditional isolation of chiropractic schools from the mainstream of higher education in the United States. Owing to exclusion from universities and teaching hospitals and to the preference for isolation among some leaders, the faculties and students of chiropractic schools have rarely enjoyed the camaraderie of regular daily encounters with clinician-scholars, scientists, and critical thinkers in other health care disciplines. Cut off from the wider health science community, the gobbledygook so often encountered among chiropractors has usually gone unchallenged within chiropractic institutions. The habits of skeptical inquiry and critical challenge of ideas that characterize the scientific process have not until recently been part of the fabric of chiropractic education.
The hundred years war between medicine and chiropractic has fostered an extreme sensitivity and resistance to criticism among DCs. Confronted with professional extermination, as embodied in the American Medical Association’s commitment to “contain and eliminate” chiropractic (Chapman-Smith 1989; Wardwell 1992), many DCs perceive any and all criticism (even from within their own ranks) as carrying the threat of annihilation (Keating and Mootz 1989). The conflict between medical doctors and DCs has also produced a penchant for marketing slogans in lieu of scientifically testable propositions. The classic example of this is the mindless reiteration that “chiropractic works,” a vacuous claim which lacks specificity and is not amenable to experimental testing. However, confronted by charges that chiropractic is quackery, chiropractors have responded by insisting that “Chiropractic Works!” and have rallied satisfied patients to convince legislators and policy makers of the validity of their methods and the justness of their cause. Slogans like this are endlessly repeated not only to the public, but among DCs themselves (and to chiropractic students). To challenge the notion that “chiropractic works” is considered heresy in most corners of the profession. Rather than skepticism and critical thinking, traditional chiropractic education has sought to instill strong belief in chiropractic (Quigley 1981) among successive generations of students. In so doing the schools have strengthened the “anti-intellectual” (Coulter 1990) traditions in the profession.
Antiscientific attitudes are also reinforced by the financial realities of a century of self- and externally imposed segregation from higher education. Although federally recognized accreditation of chiropractic colleges is now in its third decade, only one of the fifteen chiropractic schools in the United States is housed in a university. And though a few states provide capitation funds for chiropractic training (Illinois, Texas), there are no state-university-based chiropractic colleges in this country.(2) Training opportunities for chiropractors in the teaching hospitals of the nation are almost nonexistent. Chiropractic education in America is overwhelmingly tuition-based, and greater than 80 percent tuition-dependence for a college’s annual operating budget is common if not predominant. The educational consequences of this poverty are profound.
Entrance requirements for chiropractic colleges are low in comparison to those of other doctoral-level, health care professions, and competition for admission to chiropractic school doesn’t occur to any appreciable extent. Although schools may place a ceiling on the number of students that current facilities will permit, applicants are more likely to be placed on a delayed admissions list than to be rejected. Unlike health professional training in medicine or clinical psychology, the chiropractic colleges do not enjoy the luxury of choosing only the cream of the crop. Many of the schools are magnets for New Agers, theosophists, magical and mystical thinkers, and those attracted by the low admissions standards and the lure of a lucrative private practice. Almost anyone who can accumulate sixty credit hours of undergraduate liberal arts college work(3) will be admitted to these schools and can become a chiropractor. Moreover, since the largest chiropractic colleges tend to have the strongest commitments to dogma, fuzzy thinkers are likely to fill the chiropractic ranks for decades to come.
Some chiropractic college leaders are aware of and concerned about these serious problems for scientific development and disciplined practice. However, even those courageous college administrators who are willing to challenge the status quo are unable to implement major change because of financial limitations. Unless and until the states see the wisdom of incorporating chiropractic education within the mainstream of state universities and the teaching hospitals of the nation, the tuition-dependent chiropractic institutions will continue to have their hands tied behind their backs. Chiropractic students will continue to graduate with uncritical attitudes, enormous debts (typically between $50,000 and $80,000 per student), and little or no access to the mainstream health care system (from which referrals derive). This seems like a recipe for quackery, health fraud, and student loan defaults. Students and new graduates are less likely to practice skepticism when the pressing concern is to earn.
Then, too, many college leaders would resist the incorporation of private chiropractic colleges into state-supported universities. Fear of medical domination and of loss of “distinctiveness” presumably disincline many chiropractic college boards of trustees and administrations from considering the loss of institutional control inherent in amalgamation with universities. There is an understandable paranoia born of decades of persecution (justified or not) by organized medicine. In this sense, chiropractors’ professional xenophobia extends well beyond organized medicine and helps to perpetuate nonskeptical attitudes.
Conclusions
Chiropractic is confusing because it simultaneously encompasses science, antiscience, and pseudoscience. Although available scientific data support the effectiveness of chiropractors’ principal intervention method (manipulation for patients with low-back pain), the doubting, skeptical attitudes of science do not predominate in chiropractic education or among practitioners. Members of the profession, for the most part, have not yet struck that delicate balance that characterizes the “practitioner-scientist” (Keating 1992): open-mindedness in the development of theory and techniques, but caution in drawing conclusions and making claims. Nonetheless, there is a research community within chiropractic and a sprinkling of skeptics throughout the profession.
The bonesetter’s art is an ancient and valuable contribution to healing. In the United States, chiropractors are the overwhelmingly most frequent providers of this service. Yet, chiropractic has evolved as an estranged child among the other health care disciplines, and its culture has nurtured antiscientific and pseudoscientific attitudes and activities. Meaningful change, including growth of science within chiropractic, will require external support, greater integration, and wider appreciation of the diversity of values and epistemologies among chiropractors.
Acknowledgments
I wish to thank Arlan W. Fuhr, D.C., Reed B. Phillips, D.C., Ph.D., and Keith Wells, D.C., for their critical feedback concerning an earlier draft. Preparation of this paper was supported by the National Institute of Chiropractic Research and the Los Angeles College of Chiropractic. The author is solely responsible for its content.
Notes
1. There are at least four national, general professional associations of chiropractors in the United States: the American Chiropractic Association, the International Chiropractors’ Association, the National Association of Chiropractic Medicine, and the World Chiropractic Alliance.
2. In Canada, on the other hand, recommendations for medically integrated chiropractic education date at least to 1916 (Biggs 1989), and the University of Quebec has recently established a chiropractic college at its Three Rivers campus. State-supported, university-integrated chiropractic education is also found in Australia, Denmark, and South Africa.
3. Of the sixty credit hours required for admission to chiropractic college, there must be at least six credits each of general (inorganic) chemistry, organic chemistry, physics, and biology, all with laboratory. Credits in the social sciences and the humanities are also required. Cumulative grade point average must be at least a “C” (2.0 on a 4.0 scale); see McNamee 1994 for more details about admissions requirements for particular schools. Minimum admission requirements are higher at some chiropractic schools.
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Joseph C. Keating Jr. is a professor at the Los Angeles College of Chiropractic, 16200 E. Amber Valley Drive, P.O. Box 1166, Whittier, CA 90609. He teaches courses in the history of chiropractic, philosophy and reasoning, and clinical research methods.
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