Primary Care Physicians and Complementary-Alternative Medicine:
Training, Attitudes, and Practice Patterns
Brian M. Berman, MD, Betsy B. Singh, PhD, Division of
Complementary Medicine, Department of Family Medicine, University of Maryland at
Baltimore; Susan M. Hartnoll, Behavioral Research Group,
Baltimore; B. Krishna Singh, MB, PhD, Research and
Statistical Consultant Group, Baltimore;D. Reilly, MB, FRCP,
MRCGP, Research and Statistical Consultant Group, Scotland
[J Am Board Fam Pract 11 (4):272-281, 1998 © 1998 American Board of Family Practice]
Background: Physician interest in complementary medicine
is widely documented in many Western countries. The extent of level of training, attitudes
toward legitimacy, and use of complementary therapies by US primary care physicians has
not been extensively surveyed. We conducted a national mail survey of primary care
physicians to explore these issues.
Methods: Primary care specialties represented were family
and general practice, internal medicine, and pediatrics. A total of 783 physicians
responded to the survey. For the multivariate analysis, sample weights were assigned based
on specialty. Assessments were done for training, attitudes, and usage for complementary
medicine. Additional data collected included years in practice, specialty, and type of
Results: Biofeedback and relaxation, counseling and
psychotherapy, behavioral medicine, and diet and exercise were the therapies in which
physicians most frequently indicated training, regarded as legitimate medical practice,
and have used or would use in practice. Traditional Oriental medicine, Native American
medicine, and electromagnetic applications were least accepted and used by physicians.
Conclusions: Many psychobehavioral and lifestyle therapies
appear to have become accepted as part of mainstream medicine, with physicians in this
study having training in and using them. Such therapies as chiropractic and acupuncture
appear to be gaining in acceptance despite low training levels among physicians. Those in
practice more than 22 years had the least positive attitudes toward and use of
complementary therapies. Osteopathic physicians were more open than medical physicians to
therapies that required administering medication or a procedural technique. In the
multivariate analysis, attitude and training were the best predictors of use.
Therapies currently not taught or used in Western or US medical schools or institutions
are grouped within the general classification of complementary and alternative medicine.[1,2]
A widely divergent group of more than 150 different practices representing a
"hodgepodge of beliefs and treatments" falls within this heading.
In one of the most extensive efforts to map the field of complementary or alternative
medicine, the Office of Alternative Medicine, in a recent report to the National
Institutes of Health (NIH), grouped these practices into seven broad categories.
Physicians' attitudes toward alternative treatments vary among countries, suggesting
that the distinction between alternative and conventional medicine is not always clear-cut
and that many therapies previously considered fringe have become more accepted and used.
Studies in many Western countries[5-17] indicate that physician interest in the
use of complementary or alternative therapies appears substantial, but scientific evidence
does not appear to be the basis for their interest. In the United States, a
survey of primary care physicians in the Chesapeake Bay area found physicians to be not
only open to using or referring patients for certain complementary therapies but also
interested in receiving training in many complementary therapies. Other
studies have found between 55 and 94 percent of physicians to be willing to refer their
patients for a complementary therapy, although fewer (11 to 36 percent) were practicing
some form of complementary medicine themselves.[12,17] These studies have been
limited either geographically or in size, and more comprehensive surveys are needed
regarding US primary care physicians' attitudes toward the use of complementary or
alternative medicine practices.
To gauge such attitudes toward complementary medicine, we conducted a nationwide survey
of primary care physicians during late 1994 through 1995. Survey questions addressed (1)
which complementary therapies physicians considered to be legitimate medical practices,
(2) in which therapies physicians had been trained, and (3) whether physicians personally
practiced various complementary therapies. Based on the results of an earlier regional
study, we hypothesized that the greater the knowledge of complementary
medical practices (as measured through training), the more positive the attitudes toward
such practices, and the more likely physicians would utilize such practices for their
patients. It was also hypothesized that knowledge of, attitudes toward, and practice of
complementary medicine would vary based on physician specialty, type of medical degree,
and number of years in practice.
The survey sample was drawn from the 1994 American Medical Association (AMA) membership
list of family practice, general practice, internal medicine, and pediatric physicians.
Researchers requested name, address, degree, and specialty information for members
describing themselves as direct patient care providers in the areas mentioned above. Of
the 150,012 physicians meeting the criteria, 65,177 (43.5 percent) were general or family
practitioners, 55,537 (37 percent) were specialists in internal medicine, and 30,264 (20.2
percent) were pediatricians. The sampling frame was a random, hierarchical, stratified
sample selected proportionally by specialty and then by state or territory
It should be noted that AMA membership does not include all primary care physicians
practicing in the United States, and thus any generalizations are limited to those who are
members of the AMA. Nevertheless, the AMA listing is the largest available data source.
Poor physician response rates to surveys have been repeatedly documented.[18-21]
Although recommendations for overcoming this problem include multiple mailings
with a Total Design Method proposed by Dillman, researchers have found that
physician response rates can remain poor (approximately 16 percent) even with the
multiple-wave data-collection method described by Dillman and others.[24,25]
Even though data from general public surveys are mixed in terms of the differences in
early and late responders,[26,27] Leslie found that surveys of
homogeneous groups did not require high response rates for generalizability.
Because physicians are a relatively homogeneous group compared with the general public,
they might not require large samples to ensure external validity of the data.
Many researchers have found no differences in early and late responders on demographic
characteristics.[30,31] When Sobal and Ferentz tested Leslie's
contention that physicians are a homogeneous group and that high response rates are not
necessarily required for generalizability, they found that the additional responses
received in the second wave of their test mailing did not alter the representativeness of
the sample or change the results markedly. In a second study Sobal et al
found that physician samples, particularly within specialty groups, might not require
extensive follow-up efforts, nor did data lack external validity with low response rates.
Realizing that response rates from physicians might be poor in spite of a full-field
effort, that each specialty sample would be homogeneous, and that the larger the
population from which the sample is drawn, the fewer respondents are necessary for
representativeness if the sample is chosen randomly, the researchers
determined to calculate a ± 4 percent error rate for sample size by oversampling based on
an estimated response rate of approximately 20 percent.
A ± 4 percent margin of error rate required the return of approximately 602
questionnaires; 783 were returned. Sample weights were assigned for multivariate analyses
based on proportions of each specialty in the sample and subsequent questionnaire returns.
Among the three different specialty groups, the response rates were family physicians and
general practitioners, 10.6 percent; internal medicine, 13.7 percent; and pediatricians,
31.7 percent. Each specialty sample was weighted in proportion to the total population,
which was the basis for the initial sampling. The sample weights used for the multivariate
analyses were as follows: general and family practice 1.54, internal medicine 1.13, and
We prepared a cover letter, revised and refined the survey instrument previously used
in an earlier regional survey, and provided a mailer to facilitate easy return. Databases
were formatted and maintained to track respondent feedback (completion, refusal, change of
address, retirement, and so forth). Three mailing waves were followed by prompts. A
closure card requested the noncompliant survey members to please return the survey
instrument, request another one, or indicate specifically why compliance was not possible.
The three primary variables in this study were (1) training, (2) attitudes, and (3)
usage. Training was defined as any training in complementary or alternative practices and
was used as an indicator of knowledge derived from a formalized training process.
Attitudes were defined as the extent to which these physicians considered legitimate each
of the listed complementary and alternative medicine practices. Usage was divided into
"actual use" and "would use in practice"; for the purposes of the
multivariate analysis, however, actual use and would use in practice were combined.
Throughout the questionnaire, 19 specific complementary and alternative practices were
listed along with an "other" category. These practices were chosen based on
earlier surveys conducted in Britain and the United States,[7,16] and because
they represented each of the main complementary and alternative medicine categories
and some of the main complementary or alternative practices used in the United States and
other Western countries.
Whereas most of the analyses were descriptive and bivariate, we used a multivariate
model in the last section of the results to explore the effects of a set of variables on
overall use of complementary or alternative practices. For the multivariate analyses, the
training and attitudes variables were summated across the 19 complementary and alternative
practices. Regression analyses were performed to test a two-stage independent variable
model to predict physician use of complementary or alternative practices. The model was
block recursive; that is, specialty, type of degree, and years of practice were entered
first, then training and attitudes.
Profiles of Responding Physicians
The mean age of respondents was 48 years. Most of the physicians were male (74
percent), white (89 percent), doctors of medicine (91.6 percent), involved in direct
patient care (94 percent), and associated with a group or clinic-based practice (53
percent). Most spent a mean of nearly 46 hours per week in clinical care and a mean of 20
years in practice. Because response rates were expected to be low (indeed, they confirmed
previously stated assertions that physicians responding to mail surveys are likely not to
respond in reasonable proportions), an analysis was conducted to determine any differences
based on age, sex, geographic region, and type of specialty (ie, variables available from
the total AMA membership database). The results indicated that there did not appear to be
any bias based on these variables between the population and the responding sample, though
proportionately more pediatricians responded than any other specialty. For this reason,
weights were assigned for the multivariate analysis based on specialty, followed by
missing responses as discussed in the methods section.
Training was measured by the question, "Have you had specific courses or training
in any of the following?" The four choices for each complementary and alternative
practice were none, some, a lot, and advanced. For purposes of this analysis, none was
dichotomized with use (some, a lot, and advanced).
As shown in Table 1, areas where the most training was
reported were diet and exercise, counseling and psychotherapy, behavioral medicine, and
biofeedback and relaxation, with a range of 84.2 to 58.4 percent. Between 19.1 and 11.0
percent of physicians reported training in chiropractic, acupuncture, acupressure,
homeopathic medicine, herbal medicine, and art therapy. Less than 9 percent reported
training in traditional Oriental medicine, electromagnetic applications, and Native
Using chi-square analysis, we were able to explore variations in training based on the
specialty of the primary care physicians. Only training in art therapy, traditional
Oriental medicine, and Native American medicine was not significantly different among
specialties; prayer and homeopathic medicine were different at P < 0.05, and
training in all other practices was significant at P < 0.01. Overall, fewer
pediatricians and more family physicians and general practitioners had training in most of
the complementary or alternative practices.
Those relatively few significant differences among the respondents were not uniform
based on years in practice (diet and exercise, behavioral medicine, vegetarianism, and
meditation, P < 0.05). Physicians who had osteopathic degrees were more likely
than those with degrees in medicine to have training in massage therapy, therapeutic
touch, chiropractic, acupressure, homeopathic medicine (P < 0.01), Native
American medicine, and megavitamin therapy (P < 0.05).
Attitudes were measured by asking respondents to indicate one of the three following
responses toward each of the specific complementary and alternative practices: (1) I can't
say; I know very little about it; (2) it is a legitimate medical practice; and (3) it
belongs outside medicine. For the purposes of analysis, responses 1 and 3 were collapsed
into a single response category.
As evident in Table 2, those complementary and
alternative therapies with the highest level of acceptance as legitimate medical practices
were diet and exercise, counseling and psychotherapy, biofeedback and relaxation, and
behavioral medicine (98.0 to 85.8 percent). Between 57.0 and 33.3 percent of the
respondents indicated the following practices to be legitimate: hypnotherapy, massage and
therapeutic touch, acupuncture, vegetarianism, meditation, chiropractic, and prayer and
spirituality. Less than 30 percent of the respondents indicated that art therapy,
acupressure, herbal medicine, megavitamins, and homeopathic medicine were legitimate
medical practices, and less than 15 percent indicated that traditional Oriental medicine,
electromagnetic applications, and Native American medicine were legitimate.
Using chi-square analysis, diet and exercise, counseling and psychotherapy, biofeedback
and relaxation, acupuncture, vegetarianism, herbal medicine, traditional Oriental
medicine, and Native American medicine did not show variations in attitude based on
medical specialty. All others showed significant differences of at least P <
Physicians in practice for more than 22 years were the least likely to perceive
biofeedback and relaxation (P < 0.05), meditation (P < 0.05),
herbal medicine (P < 0.01), chiropractic (P < 0.01), acupuncture (P
< 0.01), and acupressure (P < 0.01) as legitimate medical practice; yet
they were the most accepting of electromagnetic applications (P < 0.05).
Herbal medicine, homeopathy, acupressure, chiropractic, and massage and therapeutic touch
were more likely to be perceived as legitimate by those with osteopathic degrees than
those with medical degrees (P < 0.01).
Usage was measured by asking respondents to indicate expertise in the listed
complementary and alternative practices along three dimensions: (1) have used, (2) would
consider using, and (3) would not consider using.
Have Used in Own Practice
Table 3 shows that 92.3 percent of the physicians
reported using diet and exercise and 71.2 percent have used counseling and psychotherapy
in their practice. Behavioral medicine and biofeedback and relaxation were therapies
practiced by 47.3 and 44.1 percent of the reporting physicians, respectively. Massage and
therapeutic touch, prayer and spirituality, vegetarianism, and meditation were used by
33.7 to 24.0 percent of the sample. Between 19.9 and 10.1 percent reported using
hypnotherapy, chiropractic, megavitamins, acupuncture, and acupressure in their own
practices. Less than 9.0 percent used herbal medicine, homeopathic medicine, art therapy,
electromagnetic applications, Native American medicine, and traditional Oriental medicine.
Would Use in Own Practice
Respondents additionally indicated that they would be willing to use the following
therapies: diet and exercise (6.5 percent), counseling and psychotherapy (24.5 percent),
behavioral medicine (43.8 percent), and biofeedback and relaxation (47.6 percent). Taken
together, the percentage of respondents who have used or would use these four
complementary therapies ranges between 98.8 and 91.1 percent. Physicians willing to use
vegetarianism (39.0 percent), prayer and spirituality (32.4 percent), meditation (42.8
percent), acupuncture (48.7 percent), hypnotherapy (48.0 percent), and massage and
therapeutic touch (30.9 percent) brought the total range of physicians who have used or
would use these therapies to between 60.4 to 67.9 percent. Less than 40 percent of the
physicians were willing to use art therapy (39.5 percent), acupressure (36.5 percent),
herbal medicine (34.3 percent), traditional Oriental medicine (33.5 percent), Native
American medicine (29.8 percent), chiropractic (29.0 percent), homeopathic medicine (27.9
percent), megavitamin (21.3 percent), and electromagnetic applications (20.6 percent) in
their practice. Combining those who would use with those who have used these therapies
produces a range of 48.2 to 24.4 percent.
Using chi-squared analysis, we found that, where usage patterns of complementary and
alternative practices varied by specialty (Table 3),
pediatricians were less likely to use complementary and alternative therapies in their own
practice (vegetarianism, chiropractic, and herbal medicine, P < 0.05; massage
and therapeutic touch, megavitamin, meditation, acupressure, acupuncture, homeopathic
medicine, P < 0.01). Family physicians and general practitioners were most
likely to use these therapies.
Those in practice for more than 22 years were least likely to use complementary and
alternative therapies in their professional role. Osteopathic physicians were more likely
than medical physicians to use such therapies as massage and therapeutic touch,
acupressure, chiropractic, and herbal medicine (P < 0.01), and homeopathy and
megavitamins (P < 0.05).
We built several regression equations to test a two-stage independent variable model
that would predict physician use of complementary and alternative practices. In stage 1 of
the regression analysis, use of complementary and alternative therapies was predicted from
three precursor variables (ie, specialty [dummy coded], type of degree [dummy coded], and
years in practice).
The results indicated that, of the three precursor variables, only length of practice
was significant (P < 0. 05). When these variables were entered in conjunction
with training and attitudes, none of the precursor variables was found to be significant.
Attitudes toward complementary and alternative practices were the most unique predictors (P
< 0.001, R2 = 0.291), followed by training in complementary and
alternative practices (P < 0.001, R2 = 0.120). Strong
collinearity between training and attitudes existed. The total explained variance for the
model with all precursor variables was R2 = 0.431.
The four areas of complementary and alternative medicine in which a majority of the
physicians in this study had training, that they used in practice, and that they clearly
considered to be a part of mainstream medical practice were diet and exercise, counseling
and psychotherapy, behavioral medicine, and biofeedback and relaxation. This group of
practices, often categorized in complementary and alternative medicine publications under
the rubric of mind-body therapies, conforms to the structural definition of
complementary and alternative medicine as therapies not generally taught in US medical
schools and institutions. Nevertheless, these practices are perhaps a good example of
therapies that have moved with time from the fringe toward the mainstream. Blumberg et al
have also found that US physicians use or refer patients most often for relaxation and
lifestyle and diet therapies. The high percentage of physicians reporting training in and
usage of these therapies is interesting, because at best only 53 to 58 percent of US
medical schools include required or elective courses in nutrition or relaxation.[37-39]
Indeed, in 1994-95 only 22 percent of US medical schools required nutrition courses, and
the curricula of such courses have been described as chaotic and haphazard.[37,39]
Other therapies that focus on psychobehavioral and lifestyle change, such as
vegetarianism, meditation, and hypnotherapy, were considered legitimate by a moderate
percentage of the physicians. Similarly, a moderate percentage had had training in these
therapies and had used or were willing to use these therapies in practice.
At the other end of the spectrum were ethnomedicines, such as traditional Oriental
medicine and Native American medicine, as well as practices that involve administration of
some type of medication, such as megavitamins, homeopathy, and herbal medicine. The lowest
percentage of physicians had training in these complementary and alternative practices,
regarded them as legitimate medical practices, and used them. Although these therapies
seem typically not to be accepted or used by physicians in the United States,[12,16,17]
homeopathy and herbal medicine are two of the most popular complementary practices among
primary care physicians in such countries as Germany and the Netherlands.[15,40,41]
It is interesting to note that acceptance of chiropractic and acupuncture by physicians in
this study appears to be quite high despite low training levels. Although the rate of use
of these therapies is low, physician acceptance would appear to be higher when rates of
attitudes toward legitimacy and rates of have used and would use are considered. This
finding is consistent with acceptance rates in other countries.[7-10,13,14,40-44]
When the results of the study were analyzed for differences based on specialty, years
in practice, and degree type, some interesting patterns emerged. Compared with the other
specialists, far fewer pediatricians appeared to be knowledgeable about and open to
complementary and alternative practices. Complementary and alternative therapies tended to
be used and accepted least by physicians who had been in practice more than 22 years.
A significantly greater percentage of osteopathic physicians than medical physicians
were open to two general groupings of complementary and alternative practices: (1)
therapies involving administration of a medication, and (2) practices using procedural
techniques. In general, osteopathic physicians had more training in these therapies, were
more likely to consider them legitimate, and were more likely to have used them. It is
perhaps not surprising that this second grouping of procedural techniques was more
accepted and used by osteopathic physicians given that manipulative therapy is considered
the chief point of departure of osteopathic medicine from orthodox medical practice.
Overall, nearly 20 percent or more of the physicians in this study had used 9 of the 19
listed therapies and one third or more were open to using 17 of them (have used or would
use combined). From 44 percent to 96 percent of physicians had referred at least 1 patient
for one or more of nine of the therapies. Training and attitudes were the strongest
predictors of usage as suggested by the multivariate model.
Our finding that knowledge of a therapy (as measured in this study through training)
best predicts its acceptance and usage mirrors the results of our earlier Chesapeake Bay
region study, suggesting once again that familiarity with, not necessarily
scientific evidence of, a therapy plays a major role in its acceptance. White
has estimated that in conventional medical practice only 10 to 20 percent of all
procedures have been shown to be efficacious by controlled trials; therefore, it is not
surprising that physicians rely on experiential knowledge. Although solid
empirical studies of complementary and alternative therapies are few and use a variety of
scientific methodologies, the body of research about complementary therapies that does
exist merits review as a building block to progressive scientific rigor.[47-51]
Efforts in this regard are being undertaken by the recently established NIH Office of
Alternative Medicine and by NIH-funded university centers for research in complementary
Some limitations to this study need to be addressed. First, this group of primary care
physicians included a very limited proportion of physicians trained as osteopathic
physicians. This difference is an artifact of the number of osteopathic physicians
belonging to the AMA and thus included in the membership list of primary care physician
groups selected for the sample. Because some significant differences were found in use of
complementary and alternative practices by type of degree, it might be interesting to
examine these findings further. Second, this survey was limited to primary care physicians
for reasons of costs. Complementary and alternative practices are frequently used for
treatment of arthritis, cancer, substance abuse, pain, and many other diseases[2,52-55]
managed by other medical specialists. A more extensive survey of physicians might further
clarify the actual usage of complementary and alternative medicine across all accepted
specialties. Finally, only 19 of more than 150 complementary and alternative practices
were included in this survey. Future researchers might choose to eliminate those therapies
included in this survey that are now considered mainstream and offer a wider array of
other complementary and alternative therapies as well as investigate and study parameters
within disease specific models.
Primary care physicians in the United States appear to be accepting and using many
therapies previously considered unorthodox and are open to others that until recently have
been unheard of or shunned by the medical establishment. The results of this study
indicate that acceptance and usage of complementary and alternative practices are strongly
predicted by a physician's knowledge of and attitudes toward a therapy. Knowledge of and
familiarity with any therapy is a necessary prerequisite for sound clinical judgments when
caring for patients. In light of the increasing interest among physicians and acceptance
of complementary medicine among the general public, research is needed to evaluate these
therapies. When educational opportunities are provided to physicians to assist them with
practice and treatment decisions, the best interests of their patients will be served.
Submitted, revised, 7 October 1997.
Address reprint requests to Brian M. Berman, MD,
Division of Complementary Medicine, Department of Family Medicine, University of Maryland
at Baltimore, Kernan Hospital Mansion, 2200 Kernan Ave, Baltimore, MD 21207.
This study was supported by a grant from the Boiron Homeopathic Foundation, The
American Academy of Family Physicians, and the Laing Foundation, Thera Trust, and the
National Institutes of Health Office of Alternative Medicine.
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