Thanks to the National Board of Chiropractic Examiners for permission to reproduce this collection of studies on Chiro.Org.

Status and Recognition of Chiropractic Care

Chiropractic is now firmly rooted in the public consciousness as a primary agent of health care management.

According to a 1990 study published in the New England Journal of Medicine, the number of visits to non-medical health care providers in 1990 totaled 425 million, 9.5% more than the total number of visits to all family physicians (Eisenberg et al.1993).

A follow-up study determined that, in 1997, total visits to non-medical providers amounted to 629 millions, exceeding the total projected visits to all primary care physicians by 63% (Eisenberg et al. 1998). Moreover, a 1998 study published in the New England Journal of Medicine reported chiropractic as the most used non-medical treatment (15.7%) (Astin 1998). The change in consumer preferences for health care is reflected in health insurance coverage. Specifically, a 1999 study found that coverage of chiropractic care is "offered by nearly two-thirds of all HMOs (65%)" (Landmark 1999, 14).

When surveyed concerning their policies toward alternative1 therapies, 43% of HMO representatives reported that they "do not regard chiropractic as an alternative therapy"but as a form of mainstream health care (11). RAND, a prestigious nonprofit research organization and "think tank," has conducted several studies of chiropractic. Dr. Paul Shekelle, a medical doctor and a researcher for RAND, stated:

"Instead of thinking of chiropractic as an alternative or some kind of therapy separate from other health care, we really should consider it equivalent" (Qtd. in Brin 1998).

Widespread consumer use of chiropractic care and its documented effectiveness have flagged the profession for major studies by governments and other organizations throughout the US, Canada, Europe, and other areas of the world. Some of the significant studies and other inquiries are reported herein.

1 In consideration of these data and because chiropractors represent the third largest primary health care profession (surpassed in numbers only by medical and dental practitioners), the chiropractic community and those served by the profession do not generally apply the terms "alternative" or "unconventional" as descriptors ofchiropractic care. Where these terms do appear in this brochure, they are utilized by authors of a particular study.

The Effectiveness of Chiropractic Care

A substantial number of systematic reviews of literature and meta-analyses2 have been conducted recently concerning efficacy, patient satisfaction, and cost-effectiveness of chiropractic care. The literature is consistent in reporting substantial evidence that chiropractic treatment is effective for both acute and chronic low-back and neck conditions (Bronfort 1999; Van Tulder, Koes, and Bouter 1997; Aker et al. 1996; Hurwitz et al. 1996; Shekelle et al. 1992; Anderson et al. 1992; DiFabio 1992; Ottenbacher et al. 1985). Many other studies reported findings indicating the effectiveness of chiropractic care for conditions other than low-back and neck pain.2

A meta-analysis is a research approach which combines outcomes and draws conclusions from many studies focused on common areas.

Acute Low-Back Pain

U.S. Government Agency Report. In 1994, the Agency for Health Care Policy and Research published Clinical Practice Guideline 14-Acute Low Back Problems in Adults (Bigos et al. 1994). The guideline defined acute low-back pain, evaluated various treatments, and made recommendations concerning the efficacy of those treatments. According to the Guideline, spinal manipulation is one of the most safe and effective treatments for most cases of acute low-back pain. Regarding the guideline, the following editorial comments appeared in the Annals of Internal Medicine: "The Agency for Health Care Policy and Research (AHCPR) recently made history when it concluded that ... spinal manipulation hastens recovery from acute low back pain and recommended that this therapy be used in combination with or as an alternative to nonsteroidal antiinflammatory drugs... Perhaps most significantly, the guidelines state that... spinal manipulation offers both pain relief and functional improvement" (Micozzi 1998, 65).

Shekelle et al. (1992): doctors of medicine and doctors of chiropractic from RAND, UCLA Schools of Medicine and Public Health, and other research organizations, conducted a literature review of 25 controlled trials and a meta-analysis of nine studies addressing chiropractic treatment of low-back pain. The literature review was published in the Annals of Internal Medicine and concluded, "spinal manipulation hastens recovery from acute uncomplicated low-back pain" (594).

Chronic Low-Back Pain

Van Tulder, Koes, and Bouter (1997), researchers in the Netherlands funded by the Dutch Health Insurance Board, retrieved and evaluated evidence from 48 randomized controlled trials conducted worldwide that addressed the treatment of acute and chronic low-back pain. Researchers found "strong evidence" for the effectiveness of spinal manipulation in the treatment of chronic low-back pain.

General Low-Back Pain

Bronfort (1999) conducted a systematic review of literature concerning the efficacy of chiropractic treatment of low-back pain. The author found evidence "of short-term efficacy for SMT [spinal manipulative therapy] in the treatment of acute LBP [low-back pain]" (107). Additionally, the author found a combination of spinal manipulation and mobilization to be effective for chronic low-back pain "compared with placebo and commonly used therapies such as general medical practitioner management" (98).

In a study reported in 1992, Anderson et al. conducted a meta-analysis of twenty-three randomized controlled clinical trials of the effectiveness of spinal manipulation in the treatment of back pain. The researchers stated, "the trend for spinal manipulation to produce better results than any form of treatment to which it was compared was consistent and strong" (193). For 86% of the outcomes, spinal manipulation was more effective than any other treatment.

In a study conducted for the Ontario Ministry of Health, Manga et al. (1993) reported that spinal manipulation is the most effective treatment for low-back pain and that spinal manipulation is "safer than medical management of low-back pain" (11).

Following a 1993 study, researchers Cassidy, Thiel, and Kirkaldy-Willis of the Back Pain Clinic at the Royal University Hospital in Saskatchewan concluded that "the treatment of lumbar intervertebral disk herniation by side posture manipulation is both safe and effective" (102).

A study conducted by T.W. Meade, a medical doctor, and reported in the British Medical Journal concluded, after two years of patient monitoring, that "for patients with low-back pain in whom manipulation is not contraindicated, chiropractic almost certainly confers worthwhile, long-term benefit in comparison with hospital outpatient management" (Meade 1990, 1431).

A 1988 study of 10,652 Florida workers' compensation cases was conducted by Wolk and reported by the Foundation for Chiropractic Education and Research. According to Wolk, back injury patients treated by chiropractors versus medical doctors or osteopaths were less likely to develop compensable injuries (injuries resulting in time lost from work and therefore requiring compensation) and less likely to require hospitalization. The author explained that chiropractors are more effective in treating low-back injuries because "chiropractic treatment, in providing more services to the patient at the outset of injury, may produce more immediate therapeutic results and may reduce the amount of time lost from work" (56).

Neck Pain

Hurwitz et al. (1996), a doctor of medicine and doctors of chiropractic from RAND and several academic institutions, conducted a review of literature on treatments for neck pain. The authors found manipulation to be more effective than mobilization or physical therapy in treating some subacute or chronic neck pain and noted that "all 3 treatments are probably superior to usual medical care" (1755).

Doctors of medicine and other professionals from the Netherlands conducted two randomized clinical trials comparing the outcomes of various treatments of chronic back and neck complaints. Spinal manipulative therapy was compared to physiotherapy, treatment by a general practitioner, and a placebo. The authors found faster and greater improvement in the spinal manipulation groups (Koes et al. 1992; Koes et al. 1992a).

Several studies (Howe, Newcombe, and Wade 1983; Verhoef, Page, & Waddell 1997) have found spinal manipulation to improve neck mobility and decrease neck pain. As Verhoef, Page, and Waddell (1997) concluded, "patients suffering from back and/or neck complaints experience chiropractic care as an effective means of resolving or ameliorating pain and functional impairments" (240).

Headache Pain

A randomized controlled trial reported by medical doctors and doctors of chiropractic in Denmark found manipulation to have "a significant positive effect" on intensity and duration of cervicogenic headaches compared to "soft-tissue" therapy (Nilsson, Christensen, and Hartrigsen 1997).

Boline et al. (1995) conducted a study comparing manipulation to pain medication (amitriptyline) in the treatment of tension headaches. The authors found that pain medication had short-term effectiveness--although with side effects--while "four weeks after the end of intervention, the spinal manipulation group showed a 32% reduction in headache intensity, 42% [reduction] in headache frequency, 30% [reduction] in over-the-counter medication usage, and a 16% improvement in functional health status... The amitriptyline therapy group showed no improvement or slight worsening" (150).

In 1998, Hack et al. reported a new anatomical discovery: bridges of connective tissue establish a direct connection between neck muscles and the protective covering of the brain and spinal cord. This is a probable cause-and-effect connection between headaches and cervical spine dysfunction. The authors hypothesized that chiropractic treatment of muscle tension headaches is effective because it can "decrease muscle tension and thereby reduce or eliminate pain by reducing the potential forces exerted on the dura via the muscle-dura connection" (22).

In 1998, Mitchell, Humphreys, and O'Sullivan described previously unreported ligaments of the neck attached to the base of the skull. This discovery has implications for manual therapy and the treatment of cervicogenic headaches caused by damaged ligaments, mainly in cases of moderate to severe whiplash.

Carpal Tunnel Syndrome

Davis et al. (1998) compared chiropractic treatment of carpal tunnel syndrome (CTS) to nonsurgical medical treatment. The chiropractic group used manipulation, ultrasound, and wrist supports while the medical group used wrist supports and ibuprofen. While both treatment groups improved significantly, the authors noted that chiropractic represents an alternative conservative treatment for CTS, especially for patients "who are unable to tolerate ibuprofen" (322).

Fibromyalgia

Blunt, Rajwani, and Guerriero (1997) concluded that chiropractic treatment of fibromyalgia resulted in clinically significant improvement in flexibility and pain levels. The authors recommended that chiropractic treatment be included in a multidisciplinary treatment regimen for fibromyalgia.

Infantile Colic

Klougart, Nilsson, and Jacobsen (1989) reported a prospective study of 316 cases of infantile colic. The authors found that 94% of the infants appeared to be helped by chiropractic treatment "within 14 days from the start of treatment" (287). The infants included in the study had moderate to severe infantile colic and were otherwise healthy, averaged two weeks of age at the outset of colic, and averaged 5.7 weeks of age at the start of treatment.
The authors found that chiropractic treatment resulted in "both a reduction of the daily length of the colic periods and a reduction of the number of colic periods per day" (287). Because recovery began between 5.7 and 7.7 weeks of age, the authors maintained that this provided substantial evidence that the improvement could not be attributed strictly to "natural cessation of colic symptoms" (286).

In a 1999 study similar to the 1989 colic study noted above, Wiberg, Nordsteen, and Nilsson found that "spinal manipulation has a positive short-term effect on infantile colic" (520). Researchers randomly placed otherwise healthy, colicky infants into one of two treatment groups: chiropractic treatment and dimethicone medication. Parents kept a diary of symptoms and behaviors before the trial to establish baseline data and continued to keep a diary of symptoms during the trial. Both groups received two weeks of treatment. The infants in the chiropractic group exhibited "a reduction of 67% on day 12" of daily hours with colic, which was nearly identical to the results of the first study. The "dimethicone group only had a reduction in daily hours with colic of 38% by day 12" (520).
The dimethicone group had several subjects drop out of the study because their symptoms worsened. These subjects and their corresponding data were excluded from the results, creating better overall improvement statistics for the dimethicone group than actually occurred. Yet, the chiropractic subjects still exhibited twice as much improvement at the end of the trials when compared to the dimethicone group.
The authors noted that "[s]pinal manipulation is normally used in the treatment of musculoskeletal disorders, and the results of this trial leave open 2 possible interpretations. Either spinal manipulation is effective in the treatment of the visceral disorder infantile colic or infantile colic is, in fact, a musculoskeletal disorder, and not, as normally assumed, visceral" (520).

Rehabilitation

In an opinion article by respected researchers on the use of chiropractic manipulation in lumbar rehabilitation, Triano, McGregor, and Skogsbergh (1997) stated that the symptom relief and improved flexibility provided by chiropractic care make it a "valuable tool," assisting and easing patients into necessary rehabilitative programs. According to the authors, not only can chiropractic treatment relieve symptoms that interrupt therapy, but it restores patients' confidence in movement, discourages chronicity, and encourages patients to continue rehabilitation.

Court Evidence of Effectiveness

Validation of chiropractic treatment through evidence presented in the legal system evolved from an antitrust suit filed by four members of the chiropractic profession against the American Medical Association (AMA) and a number of other health care organizations in the U.S. (Wilk et al. v. AMA et al. 1990).
Following eleven years of litigation, a federal appellate court judge upheld a U.S. District Court ruling that the AMA had engaged in a boycott designed to restrict cooperation between MDs and chiropractors in order to eliminate the profession of chiropractic as a competitor in the U.S. health care system.
The U.S. District Court Judge rejected the AMA's patient care defense and cited specific studies which showed that "chiropractors are twice as effective as medical physicians and physical therapists in the care and alleviation of neuro mechanical problems" ("Chiropractors File Supreme Court Response" 1990, 1). The court determined that chiropractic care was therapeutic based on evidence that "chiropractors are particularly effective in relieving long term chronic and severe pain syndromes, headaches, and stress and strain problems associated with pregnancy" (1-2).

 
The Cost Effectiveness of Chiropractic Care

For some conditions, evidence of the cost effectiveness of chiropractic is mixed; however, most studies on the cost effectiveness of chiropractic clearly indicate that chiropractic is more cost effective than other treatment options. Some discrepancy naturally results from the various strategies researchers use to evaluate costs. Managed care trends and outcome-based treatment protocols will encourage further study in this area
 

Mosley, Cohen, and Arnold (1996) concluded that for patients who had back or neck pain, "chiropractic care was substantially more cost effective than conventional care" (281).

Stano and Smith (1996) found that "[f]or both total payments and total outpatient payments, the mean cost of chiropractic first episodes ($518 and $477 respectively) is substantially and significantly lower than medical episodes ($1,020 and $598) with much of the difference in total costs because of inpatient costs" (198).

An earlier cost comparison study by Stano (1993) involved 395,641 patients with neuromusculoskeletal conditions. Results over a two-year period showed that patients who received chiropractic care incurred significantly lower health care costs than did patients treated solely by medical or osteopathic physicians.

In a 1998 study, Manga and Angus urged the Ontario government to lower chiropractic co-payments, which would grant access to more proper and prompt care for those who need it most yet can least afford it: poor and elderly patients. Once the government improves public access to chiropractic care, "direct savings to Ontario's health care system may be as much as $770 million, will very likely be $548 million, and will be at least $380 million. The corresponding savings in indirect costs--made up of the short and long term costs of disability--are $3.775 billion, $1.849 billion and $1.225 billion" (3).

In a study of work-related back pain claims in Australia, Ebrall (1992) found that the percentage of cases managed by chiropractors that required compensation days was half that of cases managed by medical doctors. The likelihood of a claim progressing to 90-day, or chronic, status was three times more likely with medical management than with chiropractic management.

A 1992 review of data from over 2,000,000 users of chiropractic care in the U.S., reported in the Journal of American Health Policy, stated that "chiropractic users tend to have substantially lower total health care costs," and "chiropractic care reduces the use of both physician and hospital care" (Stano, Ehrhart, and Allenburg 1992, 43).

Qualifications for Practicing Chiropractic

In order to become a licensed doctor of chiropractic, an individual must meet stringent academic and professional requirements, which generally include passing nationally standardized examinations. Currently, an individual must complete the following four major steps in order to become a licensed chiropractor:

-Complete two or more years of general college-level studies (Bachelor's degree required by some states)

-Obtain a Doctor of Chiropractic degree and complete a clinical extemship through an accredited four-year chiropractic college program

-Pass the National Board of Chiropractic Examiners' and/or other state-required examinations

-Satisfy any other individual state-specific requirements for licensure

Chiropractic Training

Government inquiries, as well as independent investigations, have affirmed that today's chiropractic academic training is of equivalent standard to medical training in all pre-clinical subjects. The Council on Chiropractic Education (CCE) and its Commission on Accreditation, as recognized by the U.S. Department of Education, maintain high standards in chiropractic education.Postdoctoral training in a variety of clinical disciplines and specialties is available through accredited colleges and specialty councils. Postgraduate programs include:

Applied Chiropractic Sciences
Family Practice
Industrial Consulting
Neurology
Nutrition
Orthopedics
Pediatrics
Radiology
Rehabilitation

 
Chiropractic Licensing

Chiropractic is one of many occupations that are regulated by state licensing agencies. The requirements for chiropractic licensure vary from state to state (and country to country). Some states require a Bachelor's degree as a prerequisite for licensure. To assist the various regulatory agencies in assessing candidates for licensure, the National Board of Chiropractic Examiners (NBCE) develops and administers examinations to individuals currently in the chiropractic educational system or who have completed a chiropractic education program. The NBCE also offers an examination designed for previously licensed individuals. A candidate for licensure may request that transcripts of scores from NBCE examinations be forwarded to licensing agencies that assess eligibility for licensure.Scores from NBCE examinations are made available to licensing agencies throughout the U.S. and to many licensing authorities outside the U.S.

Works Cited

(NOTE: The NBCE does NOT distribute copies of the studies cited. These must be obtained from the publisher or distribution source.)

Aker, Peter D., Anita R. Gross, Charles H. Goldsmith, and Paul Peloso. 1996. "Conservative Management of Mechanical Neck Pain: Systematic Overview and Meta-analysis." British Medical Journal 313 (23 November): 1291-129Anderson, Robert, William C. Meeker, Brian E. Wirick, Robert D. Mootz, Diana H. Kirk, and Alan Adams. 1992. "A Meta-Analysis of Clinical Trials of Spinal Manipulation." Journal of Manipulative and Physiological Therapeutics 15, no. 3: 181-194.Astin, John A. 1998. "Why Patients Use Alternative Medicine." Journal of the American Medical Association 279, no. 19: 1548-1553. Bigos, Stanley J., O. Richard Bowyer, G. Richard Braen, et a1. 1994. Acute Low Back Problems in Adults: Clinical Practice Guideline No. 14. AHCPR Publication No. 95-0642. Rockville, MD: Agency for Health Care Policy and Research, Public Health Service, U.S. Department of Health and Human Services. Blunt, Kelli L., Moez H. Rajwani, and Rocco C. Guerriero. 1997. "The Effectiveness of Chiropractic Management of Fibromyalgia Patients: A Pilot Study." Journal of Manipulative and Physiological Therapeutics 20, no. 6: 389-399. Boline, Patrick D., Kassem Kassak, Gert Bronfort, Craig Nelson, and Alfred V. Anderson. 1995. "Spinal Manipulation vs. Amitriptyline for the Treatment of Chronic Tension-Type Headaches: A Randomized Clinical Trial." Journal of Manipulative and Physiological Therapeutics 18, no. 3: 148-154. Brin, Dinah Wisenberg, July 2 1998, "Study Credits Chiropractors with Right Procedures," The Scranton Times, 14+.Bronfort, Gert. 1999. "Spinal Manipulation: Current State of Research and Its Indications." Neurologic Clinics of North America 17, no. 1: 91-111. Cassidy, J. David, Haymo W. Thiel, and William H. Kirkaldy-Willis. 1993. "Side Posture Manipulation for Lumbar Intervertebral Disk Herniation." Journal of Manipulative and Physiological Therapeutics 16, no. 2: 96-103. Cherkin, Daniel C., and Frederick A. MacCornack. 1989. 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"Infantile Colic Treated by Chiropractors: A Prospective Study of 316 Cases." Journal of Manipulative and Physiological Therapeutics 12, no. 4: 281-288. Koes, Bart W., Lex M. Bouter, Henk van Mameren, et al. 1992. "A Blinded Randomized Clinical Trial of Manual Therapy and Physiotherapy for Chronic Back and Neck Complaints: Physical Outcome Measures." Journal of Manipulative and Physiological Therapeutics 15, no. 1: 16-23. Koes, Bart W., Lex M. Bouter, Henk van Mameren, et al. 1992a. "Randomised Clinical Trial of Manipulative Therapy and Physiotherapy for Persistent Back and Neck Complaints: Results of One Year Follow Up." British Medical Journal 304 (7 March): 601-605. Landmark Healthcare, Inc. 1998. The Landmark Report on Public Perceptions of Alternative Care. Sacramento, CA: Landmark Healthcare, Inc.Landmark Healthcare, Inc. 1999. The Landmark Report II on HMOs and Alternative Care. Sacramento, CA:Landmark Healthcare, Inc. Manga, Pran, Doug Angus, Costa Papadopoulos, and William Swan. 1993. The Effectiveness and Cost-Effectiveness of Chiropractic Management of Low-Back Pain. Ottawa: University of Ottawa. Manga, Pran, and Doug Angus. 1998. Enhanced Chiropractic Coverage under OHIP as a Means of Reducing Health Care Costs, Attaining Better Health Outcomes and Achieving Equitable Access to Health Services. [online]. <http://www.chiropractic.on.ca>. Meade, T. W., S. Dyer, W. Browne, J. Townsend, and A. O. Frank. 1990. "Low Back Pain of Mechanical Origin: Randomized Comparison of Chiropractic and Hospital Outpatient Treatment." British Medical Journal 300, no. 6737: 1431-1437. Micozzi, Mark. 1998. "Complementary Care: When is it Appropriate? Who Will Provide It?" Annals of Internal Medicine 129: 65-66. Mitchell, Barry S., B. Kim Humphreys, and Elizabeth O'Sullivan. 1998. "Attachments of the Ligamentum Nuchae to Cervical Posterior Spinal Dura and the Lateral Part of the Occipital Bone." Journal of Manipulative and Physiological Therapeutics 21, no. 3: 145-48. Mosley, Carrie D., Ilana G. Cohen, and Roy M. Arnold. 1996. "Cost-Effectiveness of Chiropractic Care in a Managed Care Setting." American Journal of Managed Care 2, no. 3: 280-282.Nilsson, Niels, Henrik Wulff Christensen, and Jan Hartvigsen. 1997. "The Effect of Spinal Manipulation in the Treatment of Cervicogenic Headache." Journal of Manipulative and Physiological Therapeutics 20, no. 5: 326-330. Ottenbacher et al. 1985. "Efficacy of Spinal Manipulation/Mobilization Therapy: A Meta-analysis. Spine 10, no. 9: 833-837. Shekelle, Paul. G., Alan H. Adams, Mark R. Chassin, Eric L. Hurwitz, and Robot H. Brook. 1992. "Spinal Manipulation for Low-Back Pain." Annals of Internal Medicine 117, no. 7: 590-598. Stano, Miron, and Monica Smith. 1996. "Chiropractic and Medical Costs of Low Back Care." Medical Care 34, no. 3: 191-204. Stano, Miron. 1993. "A Comparison of Health Care Costs for Chiropractic and Medical Patients." Journal of Manipulative and Physiological Therapeutics 16, no. 5: 291-299. Stano, Miron, Jack Ehrhart, and Thomas J. Allenburg. 1992. "The Growing Role of Chiropractic in Health Care Delivery." Journal of American Health Policy (November/December): 39-45. Triano, John J., Marion McGregor, and Dennis R. Skogsbergh. 1997. "Use of Chiropractic Manipulation in Lumbar Rehabilitation." Journal of Rehabilitative Research and Development 34, no. 4: . 394-404. Van Tulder, Maurits W., Bart W. Koes, and Lex M. Boater. 1997. "Conservative Treatment of Acute and Chronic Nonspecific Low Back Pain: A Systematic Review of Randomized Controlled Trials of the Most Common Interventions." Spine 22, no. 18: 2128-2156. Verhoef, Maria J., Stacy A. Page, and Stephen C. Waddell. 1997. "The Chiropractic Outcome Study: Pain, Functional Ability and Satisfaction with Care." Journal of Manipulative and Physiological Therapeutics 20, no. 4: 235-240. Wiberg, Jesper M. M., Jan Nordsteen, and Niels Nilsson. 1999. "The Short-term Effect of Spinal Manipulation in the Treatment of Infantile Colic: A Randomized Controlled Clinical Trial with a Blinded Observer." Journal of Manipulative and Physiological Therapeutics 22, no. 1: 13-16. Wilk et al. vs. American Medical Association et al., U.S. District Court (Northern District of Illinois Eastern Division) No. 76 C 3777, Getzendanner J, Opinion dated August 27, 1987.

Wolk, Steve. 1988. "An Analysis of Workers' Compensation Medical Claims for Back-Related Injuries." ACA Journal of Chiropractic (July): 50-59.