December 2006

Clinical meaningfulness of the chiropractic adjustment

Part I: Patient‑doctor communication

by Robert H. Blanks, PhD, President, Research and Clinical Science

We have been talking for several years about the importance of adopting an international chiropractic research agenda. Many recognize the urgency of establishing a strong evidence‑based rationale for chiropractic, and in particular for the original tenets of chiropractic relating to the subluxation syndrome.

Although a number of researchers in chiropractic have voiced concerns about the paucity of chiropractic research and the lack of a focused research agenda, it took one of the research leaders in the field, Joseph C. Keating, Jr. PhD, to throw down the gauntlet.

A noted leader in the chiropractic research community and member of the Board of Directors for the National Institute of Chiropractic Research (NICR), Dr. Keating's hard‑hitting presentation is aptly titled "The Challenge."

The "Challenge," in his words is "to determine the clinical meaningfulness (or lack thereof) of subluxation‑syndrome." He states that "we've talked about it for more than a century" and "no one disputes the existence of subluxations," but "the questions has always been whether or not subluxations (or other segmental lesion) has health consequences (i.e., subluxation‑syndrome)."

His presentation goes on to describe the problem of defining "clinical meaningfulness," how to apply scientific methodology to evaluate subluxation‑syndrome in terms of clinical outcome measures such as assessments or change in any specific disease or "condition." He ends with the question, "Who will do the research?"

I acknowledge the importance of Dr. Keating's challenge to the profession and suggest several ways to address the central question, i.e., what is the connection between subluxation‑correction and health.

This first article will discuss clinical meaningfulness as it relates to patient‑doctor communication.

Three follow‑up articles will evaluate the meaningfulness of subluxation‑correction as it relates to the other well‑documented stake‑holders: the scientific community, public and private third‑party payers, and, finally, public health and health policy reform.[1]

Two meanings of clinical meaningfulness

The term clinical meaningfulness ‑‑ like the synonymous terms clinical significance, practical importance, clinical implication, clinical utility ‑‑ is often used in the literature, but really has just two meanings. Observed changes or differences are either significant ‑‑ they "mean something" ‑‑ or they are not meaningful and should be ignored.

Depending on the field, the outcome criteria and levels for clinical meaningfulness are established empirically. Operational definitions are needed that take into account the opinions of all stakeholders and needs of the environment.

To test the clinical meaningfulness of vertebral subluxation we need to conduct clinical research. Research begins with defining the research question and, as Dr. Keating points out, "subluxation syndrome, the traditional chiropractic concern, is a theoretical (i.e., hypothetical) notion which proposes a relationship between joint dysfunction and health consequences (diseases)."

Others in the field have voiced similar opinions.[2] The problem, then, is how to define the scientific question to eventually test the cause‑effect relationship between the subluxation and health consequences. In other words, what is the predictive power of subluxation‑correction for any specific disease or condition?

The key to the problem of establishing clinical meaningfulness of subluxation correction is to define which disease or condition will serve as the indicator.

Few would argue that chiropractic has already established itself in the musculoskeletal arena, where the chiropractic adjustment has been linked to resolution of pain and other musculoskeletal conditions.

But, as Dr. Keating and others point out "no controlled clinical trial of the effect of spinal manipulative therapy has, to date, included ... a subluxation element."[2]

What can be said about establishing a subluxation element for the host of non‑musculoskeletal conditions and general health, wellness and quality of life?

That's what RCS (Research & Clinical Science) wants to find out.

To do this, the RCS research involves the survey of large populations of controls (assessment of individual's who have not receive chiropractic care) and individuals undergoing regular chiropractic care in a clinical setting.

The number of subjects (patients and controls) is sufficient to apply large scale statistical analyses of objective (clinical indicators, instrumentation, patient sociodemographics, etc.) and subjective outcome measures (quality of life, patient satisfaction and disease/condition inventory, etc.).

Conducting a statistically controlled epidemiological survey makes it unnecessary to address specific diseases or conditions per se to test the causal link (clinical meaningfulness) between subluxation correction and health.

In short, by using large clinical populations and multivariate analyses, it will be possible to demonstrate a causal link between subluxation‑correction and health. This allows the practitioner, as trained in the chiropractic colleges, to continue a responsible clinical approach, i.e., the detection, analysis and correction of subluxation, and not be forced to diagnose and treat diseases.

However, the epidemiological studies are only a first step in establishing clinical meaningfulness of subluxation‑correction.

RCS investigators will also analyze sub‑samples of the large data repository and publish case reports on interesting new areas and/or benefits of chiropractic.

In parallel, we will be collecting data on research volunteers who haven't had chiropractic care, thereby permitting the use of case‑controlled design.

This particular research design compares persons with a given condition or disease (the cases) and persons without the condition or disease (the controls) with respect to antecedent factors.

Chiropractic patients from the participating offices will be followed through time, permitting a very powerful research design called a time series where, in essence, each patient is his or her own control.

The challenge over the next two years will be to put in place a structure to track the necessary experimental and control cohorts for such a longitudinal study.

This means tracking a large population of individuals who are under chiropractic care and another group not under care but who return on a regular basis to undergo the same assessment as those patients being tracked.

Eventually, we will have sufficient data to design and conduct clinical trials into new and exciting areas for chiropractic (e.g., woman's health, immune status, etc.).

Interpreting clinical meaningfulness

Quality of life (QOL) measures and other patient‑centered outcome measures have become important tools for evaluating clinical outcomes and for improving patient‑doctor communication. Quality of life assessment has been included in many chiropractic studies and is an essential part of the RCS assessment.

The clinical meaningfulness of QOL assessment lies in the additional information it provides and its impact on the decision‑making process between patient and practitioner.

There is consensus about these issues in the literature. Patients are concerned about their health, the possible outcome of the treatment prescribed and its cost, but often they do not feel they have an opportunity to convey these concerns.

The way in which these concerns are addressed contributes to a patient's satisfaction and ultimately the doctor's willingness to continue care.[3]

Consequently, the patient's input to the decision and monitoring of clinical progress is essential. Not surprisingly, medical studies show that physician perceptions and clinical decisions about patient needs frequently differ from the patient's own reports.[3‑7]

For this reason, QOL and other patient‑centered outcomes provide a structured approach to convey patients' perceived needs and goals for treatment.[4]

The challenge for health professionals is identifying which QOL data are appropriate for their practice.[8] The immediate concern includes clinicians' understanding of the conceptual model that includes patient‑centered (e.g., satisfaction and QOL) measures [4], their willingness to incorporate such information into clinical practice [5,6] and the practicalities of incorporating patient‑centered QOL outcome measures into a busy office practice.[7]

In our earlier study of 2,818 patients undergoing chiropractic (Network Spinal Analysis) for wellness objectives, a QOL instrument demonstrated statistically significant changes in patient self‑reported QOL across all domains measured.

Using a retrospective recall method that allowed comparison of QOL status "before starting care," patients reported on average 15% improvement in physical state, 17% improvement in mental/emotional state, 20% improvement in their ability to handle stress, and 17% improvement in overall life enjoyment.

These statistically significant changes were achieved with regular care over a period of months. As noted in the research report, "These benefits are evident from as early as 1‑3 months under care, and appear to show continuing clinical improvements in the duration of care intervals studied, with no indication of a maximum clinical benefit." [9]

This general QOL instrument has been incorporated into the RCS assessment program, and is being used to track patient outcome measures across the hundreds of offices currently being surveyed.

The QOL information has been rendered into a single numerical score, the "Vitality Wellness Index" (VWI) that is compared with their previous values and across a large population of chiropractic patients.

The availability of the VWI and other patient‑centered outcome measures have improved patient communication, and appears to work particularly well in those practices that focus on wellness vs. treatment of specific ailments.

Data collection is proceeding, but it is hoped that a large‑scale study on patient communication using quality of life measures in a chiropractic setting will help the profession evaluate the advantages of QOL data and their clinical meaningfulness in the clinical practice of chiropractic.

As in other health fields, the chiropractic community needs to develop strategies that will permit the accumulation and analysis of large amounts of clinical data to determine the significance and meaningfulness of clinical practice parameters and interventions.

As described, RCS has initiated a unique research strategy to evaluate the clinical meaningfulness and causal interaction between subluxation‑correction and health. Initially, our strategy will employ epidemiological analysis of large populations of patients and controls naive to chiropractic, rather than to conduct clinical trials on specific disease.

This strategy, as will be discussed in next month's article, will provide a scientifically valid approach to determine the clinical meaningfulness linking subluxation‑correction with general health, wellness and quality of life. This approach will build the evidence‑based rationale and clinically responsible approach underlying subluxation detection, analysis and correction.

References:

1. Symonds T, Berzon R, Marquis P, Rummans TA. "The Clinical Significance of Quality‑of‑Life Results: Practical Considerations for Specific Audiences." Clinical Significance Consensus Meeting Group. Methods to explain the clinical significance of health status measures. Mayo Clin Proc. 2002;77:572‑583.

2. Leboeut‑Yde C. "How real is the subluxation? A research perspective." JMPT 1998 (Sept);21(7):492‑494.

3. Patrick D, Erickson P. "Assessing health‑related quality of life for clinical decision making." In: Walker SR, Rosser RM, eds. "Quality of Life, Assessment and Application." Lancaster, England: MTP Press; 1988:9‑49.

4. Wilson IB, Cleary PD. "Linking clinical variables with health‑related quality of life: a conceptual model of patient outcomes." JAMA. 1995;273:59‑65.

5. Meyerowitz BE. "Quality of life in breast cancer patients: the contribution of data to the care of patients." Eur J Cancer. 1993;29A(suppl 1):S59‑S62.

6. Ganz PA. "Impact of quality of life outcomes on clinical practice." Oncology (Huntingt). 1995;9(11, suppl):61‑65.

7. Wu AW, Cagney KA. "The role of quality of life assessments in medical practice." In: Spilker B, ed. "Quality of Life and Pharmacoeconomics in Clinical Trials." 2nd ed. Philadelphia, Pa: Lippincott‑Raven Publishers; 1996:517‑522.

8. Guyatt GH, Naylor CD, Juniper E, Heyland DK, Jaeschke R, Cook DJ. "Evidence‑Based Medicine Working Group. Users' guides to the medical literature, XII: how to use articles about health‑related quality of life." JAMA. 1997;277:1232‑1237.

9. Blanks RHI, Schuster TL, Dobson M. "A retrospective assessment of Network Care using a survey of self‑rated health, wellness and quality of life." J Vert Sub Res, 1997,Vol 1 (4):15‑31.

(RCS co‑founder and President Dr. Robert Blanks is Professor in the Department of Biomedical Sciences at Florida Atlantic University and a past Professor of Anatomy and Neurobiology at the University of California, Irvine. Prior to this he spent two years at the Max Planck Institute for Brain Research in Frankfurt, Germany and two years in the Department of Anatomy at Harvard Medical School. Dr. Blanks is on the Advisory Board of the International Spinal Health Institute, is a Board Member of the Council on Chiropractic Practice and is actively involved in chiropractic research. To learn more about health outcomes research and RCS, call 800‑909‑1354 or 480‑303‑1694.)