Meanwhile, recent U.S. medical guidelines (published in 1994 by the Agency for Health Care Policy and Research) recommend spinal manipulation for some patients with low back pain. That recommendation increases the likelihood that physicians will refer more people to chiropractors, who already provide most of the manipulative therapy delivered in the United States. Yet the issue remains: Concerns have been raised for years about the appropriateness of chiropractic care, and the absence of data on the quality of care has made it difficult for many physicians and patients to place confidence in chiropractors.
For that reason, a RAND research team, led by Paul Shekelle and Ian Coulter, set out to determine the appropriateness of decisions by chiropractors to use spinal manipulation to treat low back pain. Based on a review of chiropractic office records from six sites across the United States and Canada, combined with ratings from a panel of back experts and reinforced with a literature review, the research produced somewhat encouraging results.
Chiropractic decisions to use spinal manipulation were deemed appropriate 46 percent of the time, a proportion similar to conventional medical procedures studied previously. Spinal manipulation was judged inappropriate for 29 percent of those who received the treatment, a proportion the researchers say should be reduced. For the remaining 25 percent of the cases, the appropriateness of the treatment was uncertain.
"The message of our new study is a mixed one," said Shekelle. "First, everybody needs to stop treating chiropractors as if they are quacks. An appropriateness rate of roughly half is in the same ballpark as the findings [reached] for certain medical procedures when appropriateness measures were introduced a dozen years ago. Chiropractors are appropriately treating some patients, and those patients are likely to benefit as a result of their care.
"At the same time, chiropractors need to recognize that one of the missions of a health profession is to pursue and incorporate research on quality. Clearly, a 29 percent inappropriateness rate is too high."
To complete the process, the panel of nine experts--three chiropractors, two orthopedic spine surgeons, one osteopathic spine surgeon, one neurologist, one internist, and one family practitioner--rated each treatment decision either as appropriate, inappropriate, or uncertain. "Appropriate" meant the expected benefits of the spinal manipulation exceeded the expected risks by a margin sufficiently wide enough to justify the treatment.
Most decisions rated as appropriate corresponded to diagnoses of acute low back pain--or pain lasting less than three months--with no neurologic findings and no sciatic nerve irritation. Few decisions were rated as appropriate for patients with subacute low back pain--or pain lasting between three and six months. And no decisions were rated as appropriate for patients with chronic low back pain--or pain of longer than six months (see table).
Although the results provide some reassurance to those concerned about chiropractic care, the researchers say the results probably underestimate the number of inappropriate spinal manipulations. The judgment of appropriateness applies only to the decision to initiate treatment and says nothing about its frequency or duration. Most patients receive several manipulations for low back pain. It is likely that all subsequent manipulations given to a patient whose initial treatment is inappropriate are also inappropriate. And even when the initial treatment is appropriate, it is difficult to determine when treatment should cease.
Moreover, the research team had no information about the actual outcomes of the patients whose care was rated. This study did not measure the efficacy of spinal manipulation. Rather, the appropriateness criteria were developed on the basis of expected outcomes for average patients with certain clinical conditions; actual outcomes for individual patients may differ from expected outcomes for average patients.
Finally, the study assumes that office records are valid sources of information upon which to judge the appropriateness of care. There are reasons to question this assumption: The office records may have been incomplete, the clinician may not have recorded all the relevant information, and the data collectors may have made errors. Nonetheless, the researchers believe that errors of these kinds are likely to have been small.
The study was funded by the Foundation for Chiropractic Education and Research, the Consortium for Chiropractic Research, and the Chiropractic Spinal Research Foundation. However, RAND retained complete control over the design and conduct of the study and the reporting of the results.