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Institute of Medicine (US) Committee on the Use of Complementary and Alternative Medicine by the American Public. Complementary and Alternative Medicine in the United States. Washington (DC): National Academies Press (US); 2005.

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Complementary and Alternative Medicine in the United States.

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The widespread use of complementary and alternative medicine (CAM) is of major importance to today's health care consumers, practitioners, researchers, and policy makers. For example, look at the following statistics on CAM: 42 percent of people in the United States report that they have used at least one CAM therapy: however, less than 40 percent of those using CAM disclosed such use to a physician. In 1997, an estimated 15 million adults took prescription medications concurrently with herbal remedies or high-dose vitamins, bringing into play the possibility of negative interactions. Total visits to CAM providers exceed total visits to all primary-care physicians. Out-of-pocket costs for CAM are estimated to exceed $27 billion, which shows that CAM is now big business. Hospitals, managed care plans, and conventional practitioners are incorporating CAM therapies into their practices. Medical schools, nursing schools, and schools of pharmacy are teaching their students about CAM. Information about CAM flows freely in various media: newspapers, magazines, books, pamphlets, and the Internet. Friends talk to friends about remedies for specific problems.

Just what is CAM? Who is using CAM, and why are they doing so? Are CAM therapies safe? Are they effective? These are just a few of the questions surrounding the use of CAM by the American public. This chapter provides a framework for thinking about questions related to CAM use, explores the definition of CAM, describes a taxonomy for thinking about various CAM modalities, provides an overview of recent events in the history of CAM use in the United States, and briefly describes CAM activities currently under way at the National Institutes of Health (NIH) and the Agency for Healthcare Research and Quality (AHRQ).

This chapter begins by setting the context for the committee's consideration of CAM on the basis of a more general model of health care decision making.


Questions about CAM use arise at a time when providers of conventional medical care are being challenged as never before to examine the effectiveness and efficiency of health care in the United States. The Institute of Medicine's (IOM's) Crossing the Quality Chasm (IOM, 2001) provides ample evidence for the underuse of effective care, the overuse of marginally effective or ineffective care, and the misuse of care, including preventable errors, in its delivery. Widespread variation in rates of surgery and other interventions for common conditions among seemingly similar populations in different geographic regions raises concern about how doctors and patients make decisions.

The Crossing the Quality Chasm report concludes that fragmentary, incremental change will be insufficient to reach achievable levels of quality improvement in American health care. Fundamental redesign will be required, and the report offers 10 rules for redesign. Taken together, these suggestions advocate a systems-minded approach to making health care more knowledge based and patient centered.

This report is about CAM, not about the quality of conventional medicine or the way in which it is delivered. However, as will be seen, central to the definition of CAM is that its constituent elements are “other than” conventional medicine. Therefore, an appreciation of both the strengths and the limitations of conventional medicine, especially as perceived by CAM users in the United States, is necessary context for development of conceptual models to guide public and private decision making about CAM research and practices.

The principal conceptual model that the committee used to frame this report begins with the question, What do patients and health professionals need to know to make good decisions about the use of health care interventions, including CAM? Corollary questions for policy makers relate to the research necessary to support decisions as well as policies and resources to ensure the quality and efficiency of services as well as equitable access. The more general nature of the question and its corollaries, addressing health care interventions rather than CAM interventions alone, reflects the committee's view that the decision-making needs of stakeholders in the American health care economy are equivalent for conventional and CAM health care services.

For the patient with symptoms or signs that diminish the quality of life or raise concerns about the length of life, answers to simple but compelling questions are necessary for decision making. What is wrong? What will happen if I do nothing: will things get better, worse, or stay the same? What are my treatment options, and what are the benefits and harms? What will the experience of treatment feel like? How likely am I to benefit, by how much, and for how long? How likely am I to be harmed, in what way, and for how long? Those who are well and want to stay that way by preventing preventable illness ask similar questions. The best answers to these questions come from a professional knowledge base that may be more or less supported by conclusive evidence relevant to the circumstances of the particular patient at hand. When such evidence does exist and is effectively marshaled and communicated, the decisions and resulting care attain the goal of being “knowledge based.”

Good decisions depend on more than professional knowledge about treatment options and probabilities of outcomes. Different patients may be more or less bothered by the same symptoms. They may react differently to the experience of treatment itself and anticipate different reactions to the benefits or the harms, or both. Furthermore, no matter how good the evidence, there is always some uncertainty about outcomes for the individual patient. Risks that are acceptable to some may be unacceptable to others. Benefits or harms may be more or less likely to occur early or late, and patients' willingness to make trade-offs between the two is variably influenced by the timing of the good versus the bad. When particular patients' attitudes and preferences are elicited and respected, decisions about treatment and prevention and the resulting care attain the goal of being “patient centered.”

It has been argued that there is much unwarranted variation in medical practice because of failures related to management of the professional knowledge base. In some cases the necessary research has not been done. In others, it is inaccessible to clinicians at the time that decisions are made. Evidence is also misinterpreted or inappropriately applied to a patient who is different from those whose experience provided the basis for the evidence. Furthermore, different clinicians have different understandings of how a profession knows what it knows and how the knowledge base is advanced. These epistemological differences may be even greater among users of conventional and CAM interventions.

Among clinicians who practice conventional medicine, there has been a marked shift over past decades from a reliance on professional experience to a greater emphasis on more rigorous quantitative evidence derived from randomized trials and systematic reviews of multiple trials. These more rigorous approaches have more recently been used in investigations of CAM. However, among the heterogeneous interventions that comprise CAM, particularly those that depend on variable practitioner approaches and the customization of interventions to individual patients, there are significant obstacles to use of the methods that have gained dominance in testing and advancing the knowledge base for conventional medical practitioners.

Despite the evident differences between conventional clinical practice and CAM, perhaps the most promising way to find common ground is to ask the question, What kind of knowledge do people need to make good health care decisions, and how can that knowledge be continuously tested and improved? This question provides the framework for considering the appropriate clinical and policy responses to the widespread use of CAM by the American public.

Furthermore, this framework is based on a set of ethical commitments that informed the work of the committee as it proceeded with its task. These commitments are explored in detail in Chapter 6:

  1. a social commitment to public welfare,
  2. a commitment to protect patients and the public,
  3. respect for patient autonomy,
  4. a recognition of medical pluralism, and
  5. public accountability.

One of the first questions that the committee considered was, What is CAM? The following section explores this issue.


One of the difficulties in any study of CAM is trying to determine what is included in the definition of CAM. Does CAM include vitamin use, nutrition and diets, behavioral medicine, exercise and other treatments that have been integrated into conventional medical systems? Should CAM include prayer, shamanism, or other therapies that may not be considered health care practices? As discussed further in Chapter 6, the reasons for defining modalities as “CAM therapies” are not only scientific but also “political, social, [and] conceptual” (Jonas, 2002). In the United States, some of the most frequently used and well-known therapies that are recognized as CAM are relaxation techniques, herbs, chiropractic, and massage therapy (Eisenberg et al., 1998). Chiropractic, acupuncture, and massage therapy are licensed in most states. Naturopathy and homeopathy are licensed in fewer states. Numerous other therapies and modalities are considered unlicensed practices and at present few or no formal regulations apply to these therapies and modalities. The New York State Office of Regulatory Reform and CAM has identified more than 100 therapies, practices, and systems that could be considered CAM (see Appendix A for a list of therapies).

A lack of consistency in the definition of what is included in CAM is found throughout the literature. The National Center for Complementary and Alternative Medicine (NCCAM) of NIH defines CAM as “a group of diverse medical and health care systems, practices, and products that are not presently considered to be part of conventional medicine” (NCCAM, 2002). However, many would argue that a therapy does not cease to be a CAM therapy because it has been proven to be safe and effective and is used in conventional practice. “Simply because an herbal remedy comes to be used by physicians does not mean that herbalists cease to practice, or that the practice of the one becomes like that of the other” (Hufford, 2002:29).

Descriptive definitions of CAM include one by Ernst et al. (1995), who write that CAM is a “diagnosis, treatment and/or prevention which complements mainstream medicine by contributing to a common whole, satisfying a demand not met by orthodox, or diversifying the conceptual framework of medicine.” Gevitz (1988) proposes that CAM includes “practices that are not accepted as correct, proper, or appropriate or are not in conformity with the beliefs or standards of the dominant group of medical practitioners in a society.” In 1993, Eisenberg et al. defined CAM as “interventions neither taught widely in medical schools nor generally available in hospitals.”

Kopelman (2002) argues that descriptive definitions such as those offered by Ernst et al. and Gevitz do not adequately answer the question, What is CAM? Definitions that place CAM outside the politically dominant health care system fail “to offer a standard for differentiating conventional interventions and CAM other than by appealing to what is or is not intrinsic to the practices of the dominant culture. This assumes there is a reliable and useful way to count cultures or subcultures and sort them into those that are dominant and those that are not” (Kopelman, 2002). Other descriptive definitions fail because conditions change, and therefore, descriptions of the conditions are no longer accurate. For example, look at the definition of Eisenberg and colleagues (1993), which states that CAM comprises inteventions that are neither taught widely in medical schools nor generally available in hospitals; however, more than half of all U.S. medical schools provide education about CAM, health care institutions are offering CAM services, and the numbers of insurers offering reimbursement for CAM therapies is growing (see Chapters 7 and 8).

According to Kopelman, normative definitions (e.g., untested or unscientific) also fail to distinguish CAM from conventional medicine. For example, Angell and Kassier (1998) write “there is only medicine that has been adequately tested and medicine that has not.” However such a definition does not distinguish between conventional medicine and CAM because many conventional treatments have not been supported by rigorous testing. For example, a review of 160 Cochrane systematic reviews of the effectiveness of conventional biomedical procedures found that 20 percent showed no effect, whereas insufficient evidence was available for another 21 percent (Ezzo et al., 2001). Furthermore, “some CAM manufacturers adopt higher standards than are currently required in the United States and rigorously test their CAM products” (Kopelman, 2002).

Stipulative definitions (i.e., lists of therapies) are not successful in distinguishing CAM from conventional therapies, Kopelman argues, because they are not consistent from source to source and they provide no justification for the exclusion of therapies that are not included.

Given the lack of a consistent definition of CAM, some have tried to bring clarity to the situation by proposing classification systems that can be used to organize the field. One of the most widely used classification structures, developed by NCCAM (2000), divides CAM modalities into five categories:

  1. Alternative medical systems,
  2. Mind-body interventions,
  3. Biologically based treatments,
  4. Manipulative and body-based methods, and
  5. Energy therapies.

As the name implies, alternative medical systems is a category that extends beyond a single modality, and refers to an entire system of theory and practice that developed separately from conventional medicine. Examples of these systems include traditional Chinese medicine, ayurvedic medicine, homeopathy, and naturopathy.

The second category in the NCCAM classification scheme is mind-body interventions, which include practices that are based on the human mind, but that have an effect on the human body and physical health, such as meditation, prayer, and mental healing.

The third category, biologically based therapies, includes specialized diets, herbal products, and other natural products such as minerals, hormones, and biologicals. Specialized diets include those proposed by Drs. Atkins and Ornish, as well as the broader field of functional foods that may reduce the risk of disease or promote health. A few of the well-known herbals for which there is evidence of effectiveness include St. John's wort for the treatment of mild to moderate depression and Ginkgo biloba for the treatment of mild cognitive impairment. An example of a nonherbal natural product is fish oil for the treatment of cardiovascular conditions.

The fourth category, manipulative and body-based methods, includes therapies that involve movement or manipulation of the body. Chiropractic is the best known in this category, and chiropractors are licensed to practice in every U.S. state. A defining feature of chiropractic treatment is spinal manipulation, also known as spinal adjustment, to correct spinal joint abnormalities (Meeker and Haldeman, 2002). Massage therapy is another example of a body-based therapy.

The final category described by NCCAM is energy therapies which include the manipulation and application of energy fields to the body. In addition to electromagnetic fields outside of the body, it is hypothesized that energy fields exist within the body. The existence of these biofields has not been experimentally proven; however, a number of therapies include them, such as qi gong, Reiki, and therapeutic touch.

A different approach to classifying CAM modalities is a descriptive taxonomy that groups therapies according to their philosophical and theoretical identities (Kaptchuk and Eisenberg, 2001). Practices are divided into two groups. The first group appeals to the general public and has become popularly known as CAM. This group includes professionalized or distinct medical systems (e.g., chiropratic, acupuncture, homeopathy), popular health reform (e.g., dietary supplement use and specialized diets), New Age healing (e.g., qi gong, Reiki, magnets), psychological interventions, and nonnormative scientific enterprises (conventional therapies used in unconventional ways or unconventional therapies used by conventionally trained medical or scientific professionals). The second group includes practices that are more relevant to specific populations, such as ethnic or religious groups (e.g., Native American traditional medicine, Puerto Rican spiritis, folk medicine, and religious healing).

This discussion of definitions shows that no clear and consistent definition of CAM exists, nor is there a recognized taxonomy to organize the field, although the one proposed by NCCAM is commonly used. Given the committee's charge and focus, for the purposes of this report, the committee has chosen to use as its working definition of CAM a modification of the definition proposed by the Panel on Definition and Description at a 1995 NIH research methodology conference (Defining and describing complementary and alternative medicine, 1997). This modified definition states that

Complementary and alternative medicine (CAM) is a broad domain of resources that encompasses health systems, modalities, and practices and their accompanying theories and beliefs, other than those intrinsic to the dominant health system of a particular society or culture in a given historical period. CAM includes such resources perceived by their users as associated with positive health outcomes. Boundaries within CAM and between the CAM domain and the domain of the dominant system are not always sharp or fixed.

The committee chose this definition for several reasons. First, this broad definition reflects the scope and essence of CAM as used by the American public. Second, it avoids excluding common practices from the research agenda. The effect of such a broad definition means that all statements and recommendations made in this report will not apply equally to all CAM modalities and there may even be some CAM modalities for which particular statements do not apply at all. The third reason for choosing to define CAM as stated above is that it is patient centered and includes practices that people perceive to have health benefits. Fourth, it encompasses the potential for change. That is, this definition allows a therapy to be accepted as standard practice when there is evidence of effectiveness but still allows the therapy to remain a part of CAM. Furthermore, the chosen definition recognizes that the definition of “conventional” medicine will vary from time to time and from country to country, it does not presume that proven practices will be adopted, and it allows CAM to be evaluated over time.

The next section of this chapter is devoted to describing milestones in the recent history of CAM in the United States.


In 1992 the U.S. Congress established the Office of Unconventional Therapies, later changed to the Office of Alternative Medicine (OAM), to explore “unconventional medical practices.” Two million dollars was appropriated, and OAM began to develop a baseline of information on CAM use in the United States. Alternative Medicine: Expanding Medical Horizons was released in 1995 (Workshop on Alternative Medicine, 1995) and summarized the results of two workshops on CAM convened by OAM. The report (often referred to as the “Chantilly Report” because the workshops were held in Chantilly, Virginia, in 1992) examined six fields of alternative medicine and addressed issues such as research infrastructure, research databases, and research methodologies. Many of the recommendations made addressed research needs and opportunities. The report was significant because it was the result of the first NIH-sanctioned meetings held to discuss the field of CAM as a whole.

Responding to public and industry input, Congress passed the Dietary Supplement Health and Education Act (DSHEA) in 1994. DSHEA legally established the term “dietary supplement” and decreed that supplements were to be regulated similar to foods. This distinction exempted manufacturers from conducting premarketing safety and efficacy testing and eliminated the Food and Drug Administrations's (FDA's) premarketing regulatory authority. In 1995, NIH funded the Research Centers Program to provide a nationwide focus for interdisciplinary CAM research in academic institutions. Also in 1995, following a 1994 NIH and FDA workshop on acupuncture, FDA declassified acupuncture needles as an experimental product. In 1996 the Public Information Clearinghouse on CAM was established and NIH sponsored the Consensus Conference on Acupuncture, which provided evidence of the effectiveness of acupuncture for some conditions (e.g., dental pain and nausea).

The first large, multicenter trial of a CAM therapy was cofunded in 1997 by OAM, the National Institute on Mental Health, and the NIH Office of Dietary Supplements. The trial tested the effect of Hypericum (St. John's wort) for depression.

By 1998 the use of CAM was widely discussed and hotly debated. A New England Journal of Medicine editorial (Angell and Kassirer, 1998) argued that “It's time for the scientific community to stop giving CAM a free ride. There can not be two kinds of medicine—conventional and alternative. There is only medicine that has been adequately tested and medicine that has not, medicine that works and medicine that may or may not work.” An editorial in the Journal of the American Medical Association contended that “There is no Alternative Medicine. There is only scientifically proven, evidence-based medicine supported by solid data or unproven medicine, for which scientific evidence is lacking” (Fontanarosa and Lundberg, 1998). The American Medical Association devoted space to the topic of CAM in its theme journals and published a total of 80 articles and the results of 18 randomized trials. Included were editorials, descriptive articles, systematic reviews, and results of randomized controlled trials. For the first time, CAM was addressed as a complex issue and journal editors were willing to subject these articles to the same criteria and editorial review as articles addressing topics in conventional medicine.

Meanwhile, Congress, having increased the OAM budget from the original $2 million to $19.5 million, elevated OAM to the level of a national center named NCCAM in 1998, awarded it $48.9 million for fiscal year (FY) 1999, and required that NCCAM appoint CAM practitioners as members of its Advisory Council. In 1999, the Cancer Advisory Panel for CAM was established for the purpose of assessing clinical data related to CAM treatment of cancer and the first Dietary Supplements Research Center was funded jointly by NCCAM and the NIH Office of Dietary Supplements. NIH funded nine Centers for Research of Complementary and Alternative Medicine to conduct interdisciplinary research and training. Three multicenter research studies were funded: one on Ginkgo biloba for the treatment of dementia (cofunded by NCCAM and the National Institute on Aging), one on glucosamine and chondroitin sulfate for the treatment of knee osteoarthritis (cofunded by NCCAM and the National Institute of Arthritis and Musculoskeletal and Skin Diseases), and one on acupuncture for osteoarthritis of the knee (funded by NCCAM). Also in 1999 large pharmaceutical companies entered the CAM market with herbal product lines and other dietary supplements.

Several major events occurred in 2000 and 2001. In March 2000, President Clinton created the White House Commission on Complementary and Alternative Medicine Policy. The purpose of the commission was to “study and report on public policy issues in the rapidly expanding field of complementary and alternative medicine.” Furthermore, the commission was asked to report on “legislative and administrative recommendations to assure that public policy maximizes the benefits to Americans of appropriate use of complementary and alternative medicine” (Executive Order 13147, 2000). The commission's report provided recommendations about research on CAM, education and training in CAM, CAM information dissemination, delivery of CAM practices, coverage and reimbursement for CAM services, the potential role of CAM in wellness and health promotion, and the need for coordination of CAM-related efforts (WHCCAMP, 2002).

The Federation of State Medical Boards began work on CAM guidelines for physicians in 2000. The initiative was focused on “encouraging the medical community to adopt consistent standards, ensuring the public health and safety by facilitating the proper and effective use of both conventional and CAM treatments, while educating physicians on the adequate safeguards needed to assure these services are provided within the bounds of acceptable professional practice” (FSMB, 2002). The federation's House of Delegates approved the guidelines in April 2002.

The Consortium of Academic Health Centers for Integrative Medicine was launched in 2000 and by 2003 it had 22 member medical schools (see Appendix B for a list of member centers). To become a member, either the dean or chancellor is required to commit to developing programs in research, education, and clinical delivery of CAM and the school must demonstrate an organized and robust program in two of those three areas. The mission of the consortium is “to help transform medicine and healthcare through rigorous scientific studies, new models of clinical care, and innovative educational programs that integrate biomedicine, the complexity of human beings, the intrinsic nature of healing and the rich diversity of therapeutic systems” (Consortium of Academic Health Centers for Integrative Medicine, 2004).

Skeptics of CAM had long contended that the only benefit derived from CAM therapies was due to a placebo effect, not “real” effects. In November 2000 NIH hosted a workshop, The Science of the Placebo: Toward an Interdisciplinary Research Agenda, thereby helping to place placebo in the category of a “real” effect. The August 2001 issue of Science published an article on basic science mechanisms of placebo (de la Fuente-Fernandez et al., 2001). These two events triggered expanded interest among the neuroscience community in the study of the impact of nonspecific effects (e.g., expectation, context, belief) on clinical outcomes. Placebo was no longer something to be discarded or dismissed but, rather, something to be studied.

Also in 2001, NCCAM and the National Library of Medicine developed CAM on PubMed, a free, web-based access to journal citations directly related to CAM. At present, almost 40,000 citations on CAM can be found on the PubMed website. Additionally, clinically significant adverse drug-herb interactions were documented in case studies (Fugh-Berman, 2000), and St. John's wort was shown to reduce the level of indinavir, a protease inhibitor taken by AIDS patients, in plasma (Piscitelli et al., 2000).

In 2002, NCCAM launched its Intramural Program to explore CAM treatment strategies for patients at the NIH Clinical Center, the world's largest facility dedicated to patient-oriented research. Also in that year, the U.S. Department of Veterans Affairs agreed to provide reimbursement for chiropractic care, the Annals of Internal Medicine began a special series on CAM (17 publications), and Science Xpress published an article on positron emission spectrometry, imaging of the placebo response versus the response to opiod analgesics, thereby signalling continued interest in the application of modern technology to the mechanistic study of placebo-related phenomena.

NCCAM, whose budget had grown to $104.6 million in 2002, funded 10 international planning grants, and across NIH more than 200 research projects on CAM were ongoing. Also in that year, IOM established the Committee on the Use of Complementary and Alternative Medicine by the American Public. In 2003, the first two Centers of Excellence for Research on CAM were funded to increase scientific rigor in research on CAM. By 2004 the NCCAM budget was $117.8 million.

The following section explores in greater detail, the kinds of research and training efforts undertaken by NIH and the AHRQ


National Center for Complementary and Alternative Medicine

Twenty institutes and centers within NIH support ongoing CAM-related research, with NCCAM being the primary center for such research. According to the legislation creating NCCAM (P.L. 105-277), NCCAM's mandate is the “conduct and support of basic and applied research (intramural and extramural), research training, and [to] disseminate health information and other programs with respect to identifying, investigating, and validating CAM treatments, diagnostic and prevention modalities, disciplines and systems.” To achieve its mandate, NCCAM focuses on four primary areas: research, research training and career development, outreach, and integration.

To guide its research efforts, NCCAM develops program priorities through a semiannual formal review process. At present, its three priority areas are to elucidate the mechanisms of action and conduct small, well-developed Phase I and II studies; build infrastructure to support research at CAM institutions; and encourage collaboration between institutions that provide conventional medical therapies and those that provide CAM therapies (http://nccam.nih.gov/research/priorities/index.htm).

The development of research centers is the main method used to pursue research. NCCAM's CAM-related research centers can be placed into several categories: Dietary Supplement Research, Developmental Centers that partner institutions where CAM is practiced and those where conventional medicine is practiced, Centers of Excellence, Centers for CAM Research, and Exploratory Program Grants for Frontier Medicine Research. The establishment of international centers for CAM research is also an initiative in development. Unlike the other centers at NIH, which invest about two-thirds of their research funding in basic research, NCCAM places the largest proportion of its resources in clinical research; the ratio of funding for clinical research to funding for basic research was 2.5:1 in FY 2003 (NCCAM, 2004).

An impressive number of patients are participating in NCCAM-supported clinical trials (10,708 participants in 2002), more than half of whom are in Phase III clinical trials. Research on prevention (e.g., research directed to such areas as dementia, prostate cancer, and myocardial infarction) is another emphasis of NCCAM, as are studies on women's health (e.g., research examining the effects of plant-based estrogens), research on reducing or eliminating health disparities, and age-related health research.

In addition to increasing support for research project grants and research centers, since FY 1999 NCCAM has dramatically increased the funding devoted to training, career, and curriculum awards (Straus, 2003). Such funds are consistent with NCCAM's goal of increasing the number of skilled CAM researchers by making awards for CAM-related research available to pre- and postdoctoral students, CAM practitioners, conventional medical researchers and practitioners, and members of underrepresented populations in scientific research (http://nccam.nih.gov/training/overview.htm).

NCCAM also participates in a variety of outreach efforts. It maintains several outlets for both the public and the research community. The NCCAM website (http://nccam.nih.gov/) provides detailed descriptions of its ongoing activities as well as fact sheets about CAM, information on factors related to decision making about treatments, cost and payment questions, and safety alerts and advisories. NCCAM also publishes a quarterly newsletter containing updates on new and ongoing activities of the center. NCCAM also uses lectures, town meetings, and exhibits at scientific meetings as opportunities to increase people's awareness of CAM and the center.

In addition, NCCAM has established a clearinghouse, accessible by Internet and telephone in both English and Spanish, for people seeking information about CAM. The clearinghouse does not provide medical advice but does disseminate scientifically based information on CAM. Two other activities that assist with outreach are publications in peer-reviewed scientific journals, the number of which is increasing, and the development of the CAM on PubMed subsection of the National Library of Medicine's MEDLINE database.

One of NCCAM's stated goals is to “integrate scientifically proven CAM practices into conventional medicine” (http://nccam.nih.gov/about/aboutnccam/index.htm). Integration is an obvious extension of NCCAM's investments in research, research training, and expanding outreach. NCCAM hopes to aid integration by publishing research results, investigating ways in which evidence-based CAM practices can be integrated into conventional medical practice, and supporting programs that develop models for the incorporation of CAM into medical, dental, and nursing school curricula.

NCCAM is in the process of developing its second 5-year strategic plan, which will be released in January 2005. NCCAM plans to continue focusing on research, research training, outreach, and integration and intends for its second strategic plan to provide greater specificity and prioritization within these areas.

One can see from this discussion that NCCAM has an impressive and well-organized series of activities designed to advance the state of knowledge about CAM therapies and their use. NCCAM's mandated focus is on CAM, however other centers and institutes within the NIH also have impressive portfolios evaluating CAM therapies. NCCAM established the 40-member Trans-Agency CAM Coordinating Committee in 1999 to foster collaboration across these various institutes and other federal agencies involved with research on CAM. The following section describes some of the activities of NIH institutes and centers.

NIH Institutes and Centers

As seen in Table 1-1, institutes and centers other than NCCAM collectively spend millions of dollars on CAM-related activities. The NIH institutes and centers conduct research in partnership with each other and independently, facilitating a broad scope of activity in both clinical and basic research. There is ongoing research on the safety and efficacy of CAM practices for disease treatment and prevention; mechanisms of therapies including dietary supplements such as soy isoflavones and acupuncture; placebo effects; the role of spirituality in health; as well as animal studies of alternative therapies for Parkinson's disease. Table 1-1 displays the level of funding for CAM research by center or institute for the past few years.

TABLE 1-1. CAM Funding by NIH Institute or Center.


CAM Funding by NIH Institute or Center.

Office of Cancer Complementary and Alternative Medicine

The Office of Cancer Complementary and Alternative Medicine (OCCAM) within the National Cancer Institute (NCI) develops and coordinates CAM activities related to cancer. OCCAM was established in 1998. Program efforts are divided among three areas: Research Development and Support Program, Practice Assessment Program, and Communications Program.

The Research Development and Support Program funds research on CAM for the prevention, diagnosis, and treatment of cancer; CAM for cancer-related symptoms; and CAM modalities that can address the side effects of conventional treatment. Examples of recent activities include a methodology working group on research on cancer symptom management by the use of CAM, the provision of competitive supplementary funds for NCI-designated cancer centers, and a workshop on how to write a grant to receive funding for research on cancer-related CAM modalities.

The Practice Assessment Program has two primary objectives: (1) to evaluate potential therapies and assess whether future research is warranted and (2) to build a dialogue between health practitioners and researchers about CAM and cancer issues. The Practice Assessment supports the Best Case Series Program for groups of cancer patients treated with CAM therapies. Examples of best case series that have been completed are the Kelly-Gonzalez Regimen for pancreatic cancer and insulin potentiation therapy investigated by Steven Ayre.

Lastly, the Communications Program develops and disseminates information about NCI activities and obtains feedback about interests and obstacles in CAM-related research on cancer. Like NCCAM, OCCAM sponsors conferences, lectures, and expert panels to increase the quality and awareness of ongoing CAM-related research on cancer.

Office of Dietary Supplements

The Office of Dietary Supplements (ODS) is part of the Office of NIH Director and was established in 1995 in response to a congressional mandate (DSHEA, 1994). Its mission is to “strengthen knowledge and understanding of dietary supplements by evaluating scientific information, stimulating and supporting research, disseminating research results, and educating the public to foster an enhanced quality of life and health for the U.S. population.”

ODS, unlike the NIH institutes and centers, cannot directly fund investigator-initiated research. However, it partners with the NIH institutes and centers and government and private agencies to achieve its mission by supporting research, sponsoring conferences, and disseminating information. In January 2004, ODS released its 2004-2009 Strategic Plan, its second such plan, which contained five overarching goals related to research, information communication, and education. Although these goals have been adopted for the second strategic plan, greater emphasis will be placed on the use of emerging technologies, cross-disciplinary studies, training and education of investigators, translation of research, and establishment of a process for regular evaluation of ODS programs and activities.

In the last 5 years, ODS has initiated many efforts to improve the quality of research on dietary supplements. For example, ODS established a program to enhance analytical methodologies and develop standard reference preparations of dietary supplements and also created two databases that are accessible to everyone: the Computer Access to Research on Dietary Supplements database (CARDS) and the International Bibliographic Information on Dietary Supplements (IBIDS). CARDS contains information on federally funded dietary supplement research and is continually updated. IBIDS provides access to bibliographic citations and abstracts from published, international, scientific literature on dietary supplements. An additional resource for the research community and general public are evidence-based review reports commissioned through a partnership between ODS and NCCAM from AHRQ Evidence-Based Practice Centers.

ODS, in various partnerships with NCCAM, the National Institute for Environmental Health Sciences, the Office of Research on Women's Health, and the National Institute of General Medical Sciences, funds six Centers for Dietary Supplement Research. The centers emphasize botanicals and aim to identify and characterize these compounds, assess their bioavailabilities and activities, explore their mechanisms of action, conduct preclinical and clinical evaluations, establish training and career development, and help select the botanicals to be tested in clinical trials.

Agency for Healthcare Research and Quality

The AHRQ, which is part of the U.S. Department of Health and Human Services, is authorized to sponsor, conduct, and disseminate research to improve the quality and effectiveness of health care. AHRQ administers Evidence-Based Practice Centers (EPCs), which have produced evidence-based reports requested by other federal agencies on the effectiveness and safety of a limited number of dietary supplements. The reports of the EPCs are based on a systematic analysis of the relevant scientific data and are designed to differentiate the types and strengths of a comprehensive body of evidence.

Nominations for clinical topics to be reviewed by an EPC are solicited through notices in the Federal Register. The clinical topics must meet specific selection criteria including a high incidence; significance for the needs of Medicare, Medicaid, or other federal health programs; high cost; controversy about their effectiveness; and the availability of scientific data. On the basis of this process, reports on six dietary supplements1 have been reviewed as of October 2003. In addition to the evidence-based practice reports, AHRQ also funds investigator-initiated research and supports a small number of grants for CAM-related research.

The Institute of Medicine Study of CAM

The previous pages have described the progress that has been made in evaluating and understanding CAM. Yet, numerous challenges remain to be confronted as individuals seek to make decisions about the safety, effectiveness, and use of various CAM therapies and modalities. In September 2002, NCCAM, 15 other NIH centers and institutes, and AHRQ commissioned the IOM to conduct a study on the use of CAM by the American public. Specifically, the study was to:

  1. Describe the use of CAM therapies by the American public and provide a comprehensive overview, to the extent that data are available, of the therapies in widespread use, the populations that use them, and what is known about how they are provided.
  2. Identify major scientific, policy, and practice issues related to CAM research and to the translation of validated therapies into conventional medical practice.
  3. Develop conceptual models or frameworks to guide public- and private-sector decision making as research and practice communities confront the challenges of conducting research on CAM, translating research findings into practice, and addressing the distinct policy and practice barriers inherent in that translation.

Guidance was specifically sought on the following matters:

  • Study the methodological difficulties in the conduct of rigorous research on CAM therapies and how these relate to issues in regulation and practice, with exploration of options to address the identified difficulties.
  • The shortage of highly skilled practitioners who are able to participate in scientific inquiry that meets NIH guidelines and who have access to the institutions where such research is conducted.
  • The shortage of receptive, integrated research environments and the barriers to developing multidisciplinary teams that include CAM and conventional medical practitioners.
  • The availability of standardized and well-characterized materials and practices to be studied and incorporated, when appropriate, into practice.
  • Existing decision-making models used to determine whether or not to incorporate new therapies and practices into conventional medicine, including evidence thresholds.
  • Applicability of these decision-making models to CAM therapies and practices; that is, do they form good precedents for decisions relating to regulation, accreditation, or integration of CAM therapies?
  • Identification and analysis of successful approaches to the incorporation of CAM into health professions education.
  • Impact of current regulation and legislation on CAM research and integration.

IOM convened the Committee on the Use of Complementary and Alternative Medicine (CAM) by the American Public. Between February 2003 and May 2004 the committee met seven times and held five information-gathering workshops, during which testimony was solicited from any individual wishing to provide input to the committee. Over the course of this study the committee met and talked with representatives of various federal agencies, the CAM and conventional medicine communities, researchers, practitioners, educators, and patients. A liaison panel was convened with representatives both from CAM practice communities and from the conventional medicine community (Appendix D). The liaison panel met with the committee three times and provided critical input regarding many important issues including major challenges, methodological issues (e.g., outcome concepts and measures), and factors facilitating or inhibiting communication and cooperation across disciplines.

Collectively, the committee read, summarized, and analyzed articles and other information on CAM therapies, evaluation of evidence, CAM-related decision making, education on CAM, and much more. The committee commissioned a paper on methodological issues, which provided the information from which Chapter 4 was developed. The work of the committee has been challenging yet rewarding. The results of that work are contained in this report.


This report identifies the major scientific, policy, and practice issues related to CAM. It explores what is known about the use of CAM, the methods and approaches used for CAM-related research, and how this knowledge is being translated into practice. Finally, the report provides recommendations to research and practice communities as they make decisions and confront the challenges of conducting research on CAM, translate the research findings into practice, and address the distinct policy and practice barriers inherent in that translation.

This chapter has provided the context within which this report was developed, the definition and description of CAM, and a brief history and the present view of CAM-related activities under way at NIH and AHRQ. Chapter 2 describes what is known about the prevalence, cost, and patterns of use of CAM therapies and identifies the areas in which more information is needed. A discussion of the approaches to the evaluation of evidence of treatment effectiveness is presented in Chapter 3. Chapter 4 examines the need for innovative designs in research on CAM. Chapter 5 explores the existing evidence of the effectiveness for CAM and the gaps in that evidence and describes a research framework for use in filling the gaps that have been identified. Chapter 6 presents an ethical framework for CAM research, policy, and practice. Chapter 7 reviews the growing integration of CAM and explores why such integration is occurring, and Chapter 8 discusses the education of both conventional practitioners and CAM practitioners. Chapter 9 focuses on dietary supplements, and Chapter 10 presents the conclusion of the report.

For the body of the report, the committee reviewed a broad cross section of studies on use of CAM in clinical populations that were published in peer-reviewed journals. The list of studies was generated by a PubMed search covering the past 8 years plus all reviews of studies on CAM use for particular health complaints and special populations. The committee did not seek to quantify such results as studies were carried out in different clinical settings using different procedures for data collection. CAM use in such settings was cited as common if such appeared to be the case or was cited as illustrative as noted in the text. Table 2-1 and much of the content for Chapter 2 relies on an exhaustive review of those epidemiological studies of CAM use by the U.S. public which involved random, nationally representative samples that were published in the peer-reviewed medical literature. Apart from those studies cited in Table 2-1, we are not aware of additional publications which meet these straightforward criteria.

For report comments in the qualitative realm (e.g., reasons why different types of people use CAM—Table 2-2) and those referring to individual populations (i.e., CAM use among population subgroups), publications were generated by (1) a PubMed search, (2) a search of major health social science journals covering the fields of anthropology, sociology, psychology and geography, and (3) a library search of books and book chapters on CAM written by those holding advanced academic degrees and having academic positions in reputable U.S., Canadian, Australian, and British universities. Data on the range of motivations for using CAM was qualitative, and the committee made no attempt to quantify results. Data on the lack of studies on compliance/adherence with CAM was based on a PubMed search that went back 12 years.


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The topics of the six reports are as follows: Antioxidant supplements for the prevention and treatment of cancer (October 2003); Antioxidant supplements for the prevention and treatment of cardiovascular disease (CVD) (July 2003); Ephedra and ephedrine for weight loss and athletic performance enhancement (March 2003); S-adenosyl-L-Methionine (SAMe) for depression, osteoarthritis, and liver disease (August 2002); Garlic for CVD cardiovascular disease (October 2000); and Milk thistle effects (September 2000).

Copyright © 2005, National Academy of Sciences.
Bookshelf ID: NBK83804


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