Critical views of chiropractic
Chiropractic, like other alternative medical professions, has received its share of criticism from the allied health sciences and, particularly, from physicians. Some of these criticisms have also been raised within the profession. The purpose of this article is to document and explain critical views of chiropractic profession where they have been expressed by notable sources. Overall, what are the major criticisms currently made of the Chiropractic profession? Critics have claimed:
- that the theoretical basis of chiropractic is not scientifically valid.
- that Chiropractic's claims for health benefits beyond certain musculoskeletal complaints are not warranted.
- that the rejection of universal vaccination in favor of "personal choice" puts the general population at risk for epidemics if the immunization rate falls too low.
- that the rejection of vaccination by some chiropractors can expose their pediatric patients to risk of preventable illnesses like whooping cough (pertussis) and lockjaw (tetanus).
- that the care of the patients with conditions that have never been shown to be efficaciously treated by chiropractors is not warranted if these chiropractors advocate the patient forego medically recommended vaccinations and medically prescribed treatment because such care exposes patients to proven risk without offering proven benefit.
- that chiropractors are not trained in the diagnosis of medical diseases and are therefore not competent to act as comprehensive primary care health care providers.
- that Chiropractic accepts too low a standard of academic and scientific scholarship in its professional journals and schools.
- that the chiropractic profession as a whole accepts a level of self-promotion in advertising considered unprofessional and misleading by physicians.
What is the evidence that supports or refutes them? What aspects of chiropractic practice and medical practice have combined to produce these particular complaints against Chiropractic? Why is there controversy within the chiropractic profession about at least some of them? Each point raised above is discussed in more detail in the individual sections of this article.
- 1 Introduction
- 2 Chiropractic today: many styles of practice
- 3 Limited v Unlimited Provision of healthcare
- 4 Advertising
- 5 The chiropractic perspective
- 6 Criticism from other professions, and public groups
- 7 References
Chiropractic has not only survived a century of controversy, but thrived, becoming the most popular of the alternative medical professions in the West. Although the American Medical Association (AMA) vehemently criticized the profession as "quackery" and moved, thirty years ago, to eliminate it from receiving federal funds for healthcare in the United States, Chiropractic was protected by a federal judge who found those attacks motivated by a XX (need a good phrase here). At this time, the most profound criticisms of Chiropractic are probably published by the chiropractic profession itself. Despite a lack of open attacks, there is little evidence that mainstream medicine in the USA accepts Chiropractic as a fully legitimate partner in health care. The United States is particularly important when discussing the chiropractic profession, since it is the country that gave birth to the field and since it still holds the great majority of practicing chiropractors in the world. The legitimacy of the views of American medicine is certainly not above question, especially in light of the court ruling, but at least some of the criticisms made by physicians and other health science professionals are also expressed by a segment of chiropractors, and may have validity.
Chiropractic today: many styles of practice
As the varying schools and philosophies within Chiropractic are less cohesive than those within other health professions, such as Nursing or Physical Therapy, a range of practice patterns are to be expected - along with controversies over theory and practice, and debate about the future direction of the field.
Why should chiropractors be less cohesive in their views than, for example, physical therapists or nurses? Unlike these other relatively young professions, Chiropractic was begun by an individual who did not accept the newly emerging germ theory of disease , and who had no formal training in science. As Chiropractic developed, there has been increasing emphasis on educational excellence in professional schools, and on science in the classroom, but there is still a wide range of individual practice styles in current chiropractors. At one end of the range some chiropractors reject some of the basic tenets of biological medicine and adhere closely to the beliefs expressed by the founders of chiropractic , while at the other end, some practitioners reject such traditional chiropractic notions as vertebral subluxations and "innate intelligence" altogether, and focus on the objective benefits of the chiropractic techniques of care.
Why should physicans be particularly critical of Chiropractic?
Criticism from the Health Sciences has been mainly directed at the extent of chiropractic practice (the wide range of conditions for which some chiropractors offer treatment), and at the advice that chiropractors give against vaccines and standard medical treatments. There is concern that many chiropractors promote popular beliefs that lie outside their scope of practice and professional knowledge, and which are rejected by mainstream science and medicine. For example, some chiropractors believe there is a link between autism and additives in vaccines, and advise their patients on this basis, whereas large well-controlled studies have concluded that there is no such link. For these reasons, a segment of health science professionals have remained very sceptical of, or even hostile to, Chiropractic. Such hostility is most common in the USA, where regulation of Chiropractic (and the health sciences) is less vigorous than in European and Canadian health care systems, and where the chiropractic profession is much larger than in any other country.
Interestingly, the editorial view of Chiropractic from Medicine and the Health Sciences, even in the USA, has also been complimentary, at least compared to other forms of alternative medicine. One authoritative medical textbook praises chiropractic (by comparison with other fields of alternative medicine) stating: "unfortunately, most of the other fields have no agreed upon practice standards, credentialing processes, requirements for continuing education, or accountability." 
Evidence standards in chiropractic
Some critics (and some leaders of the Chiropractic profession) have warned about the over-willingness of chiropractors to accept anecdotal evidence of efficacy , while conversely, when adverse events are associated with chiropractic manipulations (for instance when a patient has a stroke soon after a spinal adjustment) chiropractors are too ready to dismiss the adverse event as “unrelated". In short, the criticism is that many chiropractors are too ready to embrace evidence supportive of chiropractic, however weak it may be, and too quick to denounce evidence of its risks unless the evidence is overwhelming. In both cases, the scientific view would advise caution in interpretation and careful further investigation under controlled conditions.
Joseph Keating, professor at the Los Angeles College of Chiropractic and a prominent historian of chiropractic has written extensively to criticise weaknesses in the arguments of chiropractors, and disreputable practices within the profession. In 1997, he said that "the doubting, skeptical attitudes of science do not predominate in chiropractic education or among practitioners". He stated that there is scientific support for chiropractic's main intervention method (spinal manipulation of patients with lower back pain), but chiropractic's culture has nurtured antiscientific attitudes, and poor science published in poor journals by chiropractors who are not well trained in science has given chiropractors false confidence about the value of various other chiropractic techniques. 
However, in 1998, Keating published a review of the articles published in the Journal of Manipulative and Physical Therapy (JMPT, the discipline's "most distinguished periodical") from 1989-1996. He concluded that scholarly activity within chiropractic had improved significantly over this period, saying that "Increases in controlled outcome studies, collaboration among chiropractic institutions, contributions from nonchiropractors, contributions from nonchiropractic institutions and funding for research suggest a degree of professional maturation and growing interest in the content of the discipline."  However, the JMPT remains the only chiropractic research journal recognized by the NIH Library of Medicine, and the only one indexed in Index Medicus.
Scientific foundations of chiropractic
The founder of Chiropractic, DD Palmer, believed that many health problems were caused by spinal misalignments ("vertebral subluxations"), that blocked the flow of "innate intelligence" along the spinal nerves. Accordingly, he proposed that chiropractic adjustments might be effective in treating a wide range of diseases, indeed, almost any disease. Since then, chiropractors have been alert for evidence that their manipulations might be beneficial in conditions not directly related to the spine. There is some evidence (from case studies) that in some cases they can be, but this evidence is generally regarded as weak because it may be influenced by the beliefs and expectations of the patient and the practitioner, and benefits may be coincidental instead of causally related. A common criticism of chiropractors has been the apparent willingness of some to offer treatment for conditions where there is no validated basis, especially those that might be life-altering without concurrent medical care .
Several concepts used by chiropractors are not used in the Health Sciences; in particular, the concepts of vertebral subluxation and innate intelligence. Some chiropractors have recognised that these concepts are impediments to better integration of Chiropractic and Health Sciences, and have urged the community to abandon them. For example, Ronald Carter, Past President of the Canadian Chiropractic Association, proposed that the "subluxation story" should be abandoned rather than simply re-packaged. He suggested that it is time for the 'silent majority' to present a rational model of chiropractic so that it can become an essential member of the health care team. 
Other chiropractors have gone further, Samuel Homola, a second generation chiropractor who has been an outspoken dissident within the profession, has argued that evidence-based chiropractic is the only way forward for chiropractors to gain greater acceptance by conventional medicine. Homola's views however represent those of only a small minority of chiropractors.
Despite overwhelming evidence that vaccination is a highly effective way of controlling infectious diseases, many chiropractors are opposed to vaccination. For example, a survey in the Canadian Province of Alberta found that 27% of chiropractors advised their patients against having themselves or their children immunized (about the same proportion as advised in favour of immunization).  In line with a general philosophy of Chiropractic to avoid medicines and drugs, 'traditional straight' chiropractors are opposed to childhood vaccination. Their main association, the International Chiropractors Association (ICA), supports a "conscience clause or waiver in compulsory vaccination laws, providing an elective course of action for all regarding immunization, thereby allowing patients freedom of choice in matters affecting their bodies and health." The American Chiropractic Association (ACA)  and the World Chiropractic Alliance (WCA) have adopted very similar positions.
Although 'freedom of choice' seems innocuous to those who are unfamiliar with the biology of vaccination, there are Public Health consequences if more than a very few people opt out of universal vaccination. For vaccination to be effective in controlling infectious diseases that spread from person to person, there must be a very high immunity rate in the population (typically 85% or higher). If too many people are unvaccinated, then there is a real risk of an outbreak of disease, and because vaccination is never 100% effective, this puts at risk not only people who are unvaccinated, but also people who have already accepted the risk of vaccination for the greater good.  Because of this, the policy has to be compulsory to be fair, otherwise a few who avoid vaccination gain benefits at the expense of the majority. Accordingly, many scientific and medical organisations have strongly and publicly supported policies of compulsory vaccination and consider it irresponsible for organisations like the ICA and ACA not to do likewise.
Those chiropractors who do advise against vaccination are not convinced that evidence for its benefits always outweigh the possible risks to an individual. When new vaccines are introduced to protect against relatively rare conditions, the balance of benefits and risks is much harder to establish, particularly because the risks are uncertain without extensive experience over a prolonged period. Such skepticism is not restricted to Chiropractic; what is particular to Chiropractic is a belief by some that chiropractic treatment is a feasible alternative to vaccination. It is not clear how common such beliefs are amongst chiropractors, but they have been expressed (for example) by the WCA. In Canada, chiropractors have been formally prevented from advising against vaccination.
Some chiropractors have spoken out against anti-vaccination views. For example, writing in Dynamic Chiropractor, Stephen Perle and Randy Ferrance harshly criticise anti-vaccination chiropractors: they write that they are not aware "of a single well-controlled study which found that chiropractic care prevented any infectious disease or reduced the severity of such a disease." They declare that it is dishonest of chiropractors to warn their patients about the danger of vaccinations without advising them of their benefits, and endorse the guidance of the College of Chiropractors of Ontario, which states, in its "Standard of Practice", that "chiropractors may not, in their professional capacity express views about immunization/vaccination as it is outside their scope of practice."
Limited v Unlimited Provision of healthcare
- It wasn't so long ago that a college president suggested, "Rigor mortis is the only thing we can't help!" Joseph Keating, chiropractic historian.
- A chiropractor is a cultist -- in the medical sense, a person who assumes all disease stems from one cause or can be cured by a single method. According to the chiropractor, there is one common denominator in all disease-nerve interference; and one panacea for every ailment -- the spinal "adjustment" that removes such interference. Kathleen Cassidy Doyle, cited by Samuel Homola
Many physicians are concerned about all treatments that have no accepted scientific basis or validated evidence of efficacy, feeling there is a risk that ineffective 'alternative' treatments might delay more appropriate treatment. In 1998, the American Medical Association (AMA) published a report on "Alternative Medicine". About Chiropractic, the report stated that manipulation has a reasonably good degree of efficacy in ameliorating back pain, headache, and similar musculoskeletal complaints, that some chiropractors limit their practices to these conditions, and that, in a national survey of referral patterns by board-certified family physicians and internists, 47% said they would refer patients for chiropractic treatment. However, the Report also said that most chiropractors continue to claim that chiropractic manipulation cures disease rather than simply relieving symptoms. "They promote manipulation as useful in a host of conditions, ranging from infectious diseases to immune therapy, even claiming to prevent future conditions from occurring (even if years away) including menstrual irregularity, difficulty giving birth, and cancer. Chiropractors commonly provide advice in nutrition and other preventive practices, and maintain that a regular series of "adjustments" is needed by most persons to maintain optimal health." In 1997, the AMA adopted as a statement of Policy that "Patients who choose alternative therapies should be educated as to the hazards that might result from postponing or stopping conventional medical treatment."
Pediatricians are especially concerned about the use of chiropractic care for infants and children, not only because of the unknown risks associated with the treatments, but also because they fear that parents unknowingly risk their children's lives by not having them seen by a physician who is properly trained in childhood diseases in a timely manner. Chiropractic treatment of infantile colic, otitis media, "excessive crying", or Attention Deficit Hyperactivity Disorder are common points of contention.
Infantile colic is a condition characterised by uncontrollable crying in infants with no clear cause: some reports suggest that chiropractic is efficacious, others do not. Chiropractors believe that any treatment that results in using less medication has value, even if it might only be effective because of its reassuring and calming effect on the mother and/or child.
Otitis media in infants is another condition that some chiropractors claim to manage efficiently. In the past, antibiotics were the treatment of choice, but recent studies suggest that waiting as long as three days before beginning a regimen could save as many as 30% from unnecessary exposure to antibiotics. Chiropractors, who also have training in physical examination, believe that they have an important 'watchful waiting' role in monitoring otitis media. However, many physicians feel that, even if chiropractic treatment of such conditions has some benefits by exploiting the placebo effect, there is a risk that false reassurance delays more appropriate medical treatment and that chiropractors, unlike pediatricians and primary care physicians, do not have the examining skills required to know when referral to a specialist in Ear, Nose and Throat (Otolaryngology) is required to prevent permanent hearing loss or complications such as brain abscess.
Drugless stance on healing
Although the practice of Chiropractic has changed considerably since its inception, most chiropractors continue to take a drugless approach to healing. Physicians remain concerned that this position can mislead some patients into thinking that all drugs are unnecessary or even harmful, and to overestimate the body's intrinsic ability to remain healthy. They fear that some patients with serious conditions that can be treated effectively with medications may be led to not take potentially life-saving treatments, such as insulin, blood pressure regulators, and cholesterol lowering drugs. They are also concerned that patients may even forego laboratory tests such as colonoscopies and physicals that can "catch" some cancers while they are still treatable.
Excessive advertising claims for the efficacy of chiropractic treatments have been criticised frequently. 
In 1992, attorney George McAndrews, who represented the plainiffs in the Wilk ''et al.'' vs AMA court case, wrote an open letter to the chiropractic profession warning that 'scare tactic' advertising damages the newly won respect within the AMA. 
However, the history of both professions in the USA is relevant in this regard. For most of the 20th century, physicians disdained advertising as both unethical and unprofessional. Chiropractors, on the other hand, enthusiastically embraced advertising and, because they were outside the organisational components of referral mechanisms found in medicine, considered this an acceptable option. More recently, the formal sanction against physician advertisements has been lifted, and currently media advertisements for such services as Cosmetic surgery and drugs are common in the USA.
The chiropractic perspective
Chiropractors suggest that they have been misunderstood by the health sciences. Because they feel that healing comes from within the body, chiropractors don't talk of 'cure', but of 'helping the body cure itself'. As a result, the traditional chiropractor sees all who suffer as in need of his or her help. The degree to which they claim to be able to help varies, not only from condition to condition but also from case to case, and also because different chiropractors use different techniques.
The spinal cord does carry a vast amount of information from peripheral organs and tissues to the brain, including sensations of pain, touch, temperature. In addition, virtually every organ and its blood supply is regulated both directly by efferent nerves, many of which travel down the spinal cord, and indirectly by neuroendocrine regulation of hormone secretion. Accordingly, disruption of spinal information flow can influence virtually every organ system. However it is not clear that any particular organ dysfunction is caused by a disorder of spinally-mediated information transfer, or whether manipulation by chiropractors could correct such a disorder. Scientists and physicians generally are skeptical about these possibilities, while believing that, in some cases, chiropractic treatment might be efficacious because it exploits the placebo effect in an efficient way.
Some chiropractors nevertheless believe that several conditions can indeed be resolved by chiropractic interventions. Such beliefs are based on their clinical experience, not on firm scientific evidence from large controlled trials, and not on any scientific demonstration of a causal mechanism linking the intervention to its claimed effect. It is possible that cases that have not responded to conventional treatment might include some where the underlying cause is indeed a disorder of neural regulation of an organ system, as the failure of conventional treatment might be taken as excluding more common causes of dysfunction, such as infectious disease. It is also possible that a symptom apparently of an organ disease is actually the result of a somatic reflex pain generated from the spine. Thus, if an organ-related complaint responds to chiropractic adjustments, it is possible that a spinal condition was the cause of the problem in the first place.  Regardless, chiropractors feel that their high patient satisfaction rates and low malpractice rates show that their patients are well informed about the limitations, the risks, and the benefits.
Criticism from other professions, and public groups
- Keeping Your Spine In Line, Adjusting the Joints, and Video - Alan Alda, PBS, Scientific American Frontiers Web Feature (combines internal and external criticism)
- Chirobase: Skeptical guide to chiropractic history, theories, and current practices - Stephen Barrett MD and Samuel Homola DC (combines internal and external criticism)
- Novella S (1997) Chiropractic: Flagship of the Alternative Medicine Fleet Part One and Part Two