J Chiropractic Humanities 2008; 15 (1): 19–26 ~ FULL TEXT
Monica Smith, DC, PhD, Lynn A. Carber, MPM
Palmer Center for Chiropractic Research,
Palmer College of Chiropractic,
90 East Tasman Drive,
San Jose, CA 95134
Objectives This paper provides new information that describes chiropractors’ professional identity relative to their concept of subluxation in chiropractic practice and education.
Methods We performed a pragmatic, descriptive, cross-sectional survey of state-board licensed chiropractors in the US during 2002-03 to assess their attitudes and behaviors about their use of “subluxation” in practice. We did not define nor specifically operationalize, a priori, the term “subluxation”, but instead allowed each individual doctor of chiropractic to self-define the concept “subluxation” in their survey responses.
Results Of all US state-board licensed DCs (N=67,217), 5,931 were surveyed. Nearly 50% of those surveyed responded. Many surveyed chiropractors generally agreed that their chiropractic education and clinical approach is “subluxation-centered”, that the concept of “subluxation” is important to their clinical care decisions, and that they use the term “subluxation” when communicating with patients, other healthcare providers, and third-party payors.
Discussion/Conclusion Based upon those surveyed, chiropractors seem to embrace “subluxation-based” terms as well as other clinical approaches to describing their care for chiropractic patients. Understanding the complex nature of chiropractic approaches to health care provision may carry implications for current initiatives to advance evidence-based chiropractic practice and clinical training, enhance successful and comprehensive biopsychosocial management of the multicausal and complex health concerns of chiropractic patients, and improve overall delivery of optimal integrative health care. Further inquiry on this topic should focus methodological and conceptual attention to differentiating how contemporary chiropractors self-define and clinically apply the concept of subluxation.
Key indexing terms: Chiropractic, Subluxation, Health Occupations
From the Full-Text Article:
An ongoing discourse focuses on the term
“subluxation” as a concept that has been
central to chiropractic professional identity,
philosophy of chiropractic, and chiropractic
history. Within the general spirit and
framework of hypothetico-deductive
scientific method, we collected descriptive
observational data about the application of
subluxation in contemporary chiropractic
practice. In-depth epistemological
exploration or analysis, such that
differentiating between “subluxation” as a
dynamic, kinetic, neurophysiological
“vertebral subluxation complex” or as a
static ‘bone out of place’ creating nerve
interference that are unique to the discipline
of chiropractic, or as an anatomical “partial
dislocation” as traditionally defined in
medicine, [1, 2] is beyond the scope and
purpose of this study.
The purpose of this paper is to report
findings from a survey of US chiropractors
regarding their attitudes and behaviors
relative to the concept of “subluxation”, as
they self-define the term, in contemporary
chiropractic clinical practice and education.
We also discuss potential implications of
these findings to an evolving chiropractic
professional identity within the context of a
biopsychosocial model for health care
provision and integrative health care
We surveyed US chiropractors in 2002-03
using a scientifically rigorous and complex
survey methodology. This survey of
chiropractor attitudes and behaviors toward
subluxation, was embedded within a more
encompassing multi-topic survey endeavor
consisting of 36 distinct survey instrument
components that were combined in various
permutations to create 38 versions of a
survey set that was distributed to 3 separate
survey cohorts within a non-replacement
sampling frame, and we have reported our
study methods in more detail elsewhere. 
In addition to basic demographic data, we
asked chiropractors to rate their agreement
with the statements presented in Table 1 in
order to ascertain the extent to which the
concept of subluxation guides their clinical
decisions or their communications with
patients, other healthcare providers, or thirdparty
payers. We also asked the extent to
which the chiropractor combined a
“subluxation-based” clinical approach with
other “non-subluxation-based” clinical
approaches for the care of patients in their
chiropractic practice, using the diagramprompted
query format included in Appendix 1 of this report. We pre-validated
our survey questions by pilot-testing on all
representatives drawn from the leadership
rosters of the Congress of Chiropractic State
Associations (COCSA), Federation of
Chiropractic Licensing Boards (FCLB), and
National Board of Chiropractic Examiners
We drew our randomized survey sampling
frame (n = 5,931) from a master list of all US
state-board licensed DCs (N = 67,217), and
employed 3 mailings plus phone follow-up
of non-respondents, to yield an eventual
mail survey response rate of approximately
50% and an overall contact rate of
approximately 60%, a rate comparable to
that of other surveys of busy professionals. [4–8]
We analyzed our survey data using SPSS
for Windows version 12.0 (SPSS Inc,
Chicago, IL). This study was reviewed and
approved by the Palmer College Institutional
Similar to the demographics reported in
other US surveys of the chiropractic
profession, the respondents to our 2002
survey also reflected a majority white
(approximately 90%) and male
(approximately 80%) constituency, engaged
in fulltime practice (85%). Most surveyed
DCs provided care at a single practice
location (90%), as a solo practitioner
(approximately 70%). On average, our
surveyed chiropractors were 46 years old
and in practice for 16 years.
Survey respondents were graduates of the following
Palmer, both schools (28%)
Life, both schools (14%)
New York (7%)
Cleveland, both schools (7%)
Western States (4%)
Sherman (2%) and
Bridgeport (less than 1%).
specifics of our survey respondent
demographics have been reported in more
detail elsewhere  and are therefore reported
more briefly here (e.g. in this report we have
collapsed separate categories for “Palmer Davenport”,
“Palmer-West”, and “Palmer-unspecified”
schools into a single category
“Palmer College” representing both Palmer
schools existing at the time of the survey, as
we also collapsed for this report Life and
As reported in Table 1, most surveyed
chiropractors generally agree that their
chiropractic education and clinical approach
was “subluxation-centered”, that the concept
of subluxation is important to their clinical
care decisions, and that they use the term
“subluxation” when communicating with
patients, other healthcare providers, and
third-party payors. Forty eight percent of
chiropractors report that their chiropractic
college education was predominantly
subluxation-based, while 41% of
chiropractors state that their continuing
education within the past year was
predominantly not subluxation-based (see
The data reported in Figure 1 suggest a more
complex picture regarding how
chiropractors specifically apply the concept
of subluxation in actual clinical practice.
Most chiropractors typically reported that
over 75% of their clinical approach to
addressing musculoskeletal or
biomechanical disorders such as back pain
was “subluxation-based”. Conversely, most
chiropractors also reported that less than
20% of their clinical approach was
“subluxation-based” for patient complaints
deemed to be principally problems with
circulation, digestion, or similarly “visceral”
The results from our survey of chiropractor
attitudes about subluxation seem to be in
both accordance and discordance with
survey results as recently reported by
McDonald et al.  Both of the surveys were
conducted during the same general
timeframe (2002-03) and employed similar
methodologies of pre-validating survey
items via pilot-testing, and an original
mailing followed up with 2 reminder
mailings to non-responders. The two surveys
differed on important dimensions that could
also partly account for some of the
differences between our respective study
findings. McDonald et al surveyed
chiropractors from Canada, Mexico, and the
US, sampling from a North American
distribution mailing list. We restricted our
survey to only US chiropractors, and
sampled from a master list of all US stateboard
licensed DCs. As well, the two studies
differed with respect to how the subluxation
queries were specifically constructed and
operationalized within each survey.
Findings from both surveys indicate that a
majority of the chiropractors we surveyed
find clinical utility in, and it is possible that
they may favor retaining professionally, the
general concept of subluxation or vertebral
subluxation complex in chiropractic
practice. In our survey, over 70% of
chiropractors report that subluxation is
important to their clinical decisions and
guides their clinical care of patients.
McDonald et al.  report that over 88% of
their surveyed chiropractors favor retaining
in the profession the term vertebral
Findings from the two surveys appear to diverge markedly, however, regarding chiropractor attitudes about the connection between subluxation and “visceral” disorders. McDonald et al  report that a strong majority (over 75%) of their surveyed chiropractors believe that subluxation is a significant contributing factor to 50% or more of visceral disorders. In stark contrast, most of our surveyed chiropractors seem to believe that a subluxation-based clinical approach may have limited utility for addressing visceral disorders, and greatly favor non-subluxation-based clinical approaches for such conditions (Fig 1). The two studies differed significantly as to how the subluxation queries were specifically formulated and posed to survey participants, which could readily account for the apparent differences in our respective findings. A diversity of chiropractic opinion regarding the connection between subluxation and visceral disorders may be reasonable and perhaps even expected, given that multicausal models of disease and dysfunction have now become fairly well established in the health sciences, widely accepted amongst most clinical disciplines, and are taught in accredited chiropractic colleges. A given chiropractor, at a given point in time, may even express varied opinions regarding the presumed connection between subluxation and visceral disorders, depending on the state of currently available evidence and understanding about the specific nature of the visceral disorder in question, the extent to which other possible contributing factors are known or suspected, and the extent to which the available scientific evidence or clinical experience may offer reasonable options for chiropractic or other care for that particular visceral disorder in that particular patient. That is, we suggest that disparate patterns of chiropractor opinion on the presumed utility of subluxation-based clinical approaches for biomechanical pain disorders vs. visceral disorders may also reflect to some degree, an evidence-based assessment by practicing chiropractors which has been appropriately informed by the extent of currently available evidence or their direct clinical experience. We echo the call for more effort devoted to developing an evidence base of all clinical entities treated in chiropractic clinical practice and for better documentation of common locally symptomatic subluxations as well as subluxations that may cause more distant neurophysiological effects. 
We also note another commonality between our study and the McDonald et al study: we did not define nor specifically operationalize, a priori, the term “subluxation” for our surveyed chiropractors. Rather, we left it for each individual chiropractor to self-define the concepts “subluxation”, “subluxation-centered”, and “subluxation-based clinical approach” in their responses. Neither we, nor McDonald, can interpret or infer from our limited findings how our surveyed chiropractors self-defined the concept of subluxation, whether as a dynamic, kinetic, complex, physiological phenomenon, or as its more typically allopathic usage of a static, anatomical “partial dislocation”, or perhaps even some other conceptual definition altogether. Future focused study along this line of inquiry would be needed to reveal such subtleties and further clarify possible variation in chiropractor attitudes and behaviors regarding the entity, and the presumed clinical utility, of subluxation in contemporary chiropractic health care.
Other limitations of this study we note: we limited our survey sampling frame to only those Doctors of Chiropractic licensed in the US. Based on data gathered in our survey phone follow up, nonrespondents to our mail survey may have disproportionately represented those chiropractors closer to retiring from practice and those having a propensity to disengagement from collective actions of the chiropractic profession (our comparison of survey respondents to nonrespondents has been reported in systematic detail elsewhere ). We did not define nor specifically operationalize, a priori, the term “subluxation”, but instead allowed each individual chiropractor to self-define the concepts, thus if we had provided a definition, it is possible the responses may have been different. As well, we did not operationalize our survey queries nor collect our survey data in such a manner as to allow for statistically robust inferential testing of more focused hypotheses, such as the possible relationship or interaction between a given chiropractor’s perception of subluxation, and their educational background, age, years in practice, or state scope of practice, to name just a few. Future study along this line of inquiry may also be warranted to explicitly test such hypotheses of potential interest.
Comprehensive, biopsychosocial approaches to care of the chiropractic patient have added utility for addressing a multitude of complex multi-causal health disorders. Our survey findings lend support to the notion that the typical doctor of chiropractic is not a simplistic ideologue in their clinical approach. Rather, our findings support and we respect the suggestion that contemporary practicing chiropractors are capable of reconciling complex notions of health, well-being, and dysfunction, by tailoring specific care for specific disorders in specific patients.  An agenda for further advancing chiropractic as a clinical discipline and chiropractic as a valued health care choice should also include attention to developing more fully all clinical skill sets that are requisite to successful delivery of a comprehensive biopsychosocial approach to health care. In particular, chiropractic research, education, and practice should emphasize the appropriate integration of cross-disciplinary approaches to address the emotional and mental health, as well as the physical health needs, of those patients who utilize chiropractic health care. Finally, our study findings may offer insights for engaging effective discourse within the chiropractic profession, by reinforcing the idea and confirming the existence of a temperate “moderate majority” in the profession. We submit that a moderate majority of chiropractors likely possesses a well-considered and complex, balanced yet encompassing, pattern of ideas, held values and expressed preferences. We agree as well with calls that the time has come to advance our chiropractic professional discourse beyond the contrived dichotomies and polarized polemics of our past, [12, 13] and to temper the rhetoric and intensify our professional focus on the underlying shared values, purpose, and identity, that will move us most successfully into our future.
Appendix 1: From the survey of Chiropractors 2002-03,
graphically-prompted queries on subluxation
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