Over the last 30 years, the fields of complementary and alternative medicine (CAM) research and practice have grown substantially, both at national as well as international levels. The growing acceptance of CAM by conventional practitioners and the increasing recognition that several of these therapies and disciplines play a prominent role in the health of patients have significantly impacted its use and study. However, public debates as well as the scientific literature suggest the need to revisit the terms and definitions used to refer to CAM practitioners, therapies, and products that have framed research and practice to date [1–6]. Facilitating meaningful change in healthcare terminology can be complex and challenging. The term CAM represents a particular challenge, in part because the topic is politically charged, but also because depending on the healthcare system context (national and international), its meaning changes.
Plethora of terms and definitions
Since 1990, several definitions of CAM have been offered, particularly among healthcare researchers. Complementary medicine was originally defined as a “diagnosis, treatment and/or prevention that complements mainstream medicine by contributing to a common whole, by satisfying a demand not met by orthodoxy or by diversifying the conceptual frameworks of medicine” . Then, the term alternative made its introduction and CAM was used to refer to “practices neither taught widely in US medical schools nor generally available in US hospitals” . When the popularity of the field and use of the term of CAM increased, especially among the general public, and CAM disciplines such as chiropractic and osteopathy made their appearance in university curricula, the definition evolved into “types of therapies or products that are currently not considered to be part of conventional medicine” . However, this is a description by omission: it describes CAM by what it is not.
Nevertheless, definitions of CAM have become inclusive in other ways. Often definitions acknowledge cultural context, since what is considered CAM in Western medicine might be considered mainstream in other countries (for instance, acupuncture in North America versus China). Zollman’s definition is a good example: “Complementary and alternative medicine (CAM) is a broad domain of healing resources that encompasses all health systems, modalities, and practices and their accompanying theories and beliefs, other than those intrinsic to the politically dominant health system of a particular society or culture in a given historical period.” . Similar to the World Health Organization’s definition, these definitions portray CAM as a moving target, which represents a significant limitation in our contemporary multicultural societies where different healthcare approaches are available . Moreover, culturally-specific definitions may preclude the research community from gathering all possible evidence on CAM and its safe and effective application in patient care . As a consequence, this lack of consensus limits the healthcare practitioners’ ability to practice evidence-based medicine.
Wieland and colleagues have recently published a working definition of CAM for the Cochrane Collaboration, consisting of a closed list of therapies and products (e.g. the superseding topics: alternative medical systems, natural product-based therapies, energy therapies, manipulative and body-based methods, and mind-body interventions) that were deemed relevant to be classified as CAM . As opposed to previously published theoretical definitions (on which most CAM definitions depend), this definition has the advantage of clearly identifying what should be considered CAM, thus creating an objective and reproducible operational definition for CAM. Nonetheless, as recognized by the authors, this definition is still subject to re-evaluation over time and its meaning depends on the dominant healthcare system; two stipulations that seem unavoidable when it comes to formulating a working and internationally-accepted definition. Interestingly, this working definition is similar to the one originally proposed by the NCCAM and recently revised by its representatives, showing how little agreement there exists on terminology in the research community. Ultimately, this list of therapies is probably as close to an operational definition as the research community has come.
In addition to the multiple definitions used to refer to these therapies, products and disciplines, the term CAM itself is puzzling. First, it combines two mutually exclusive terms: “complementary” suggests it can be used in tandem with biomedicine, while “alternative” means a substitution for biomedicine. Moreover, a specific therapy could be used both in combination with conventional care, or on its own as an alternative to conventional care. Second, many consider the term CAM inadequate because of its marginalizing implications. On the one hand, the definition borrows terminology from biomedicine and is comparable to it, but on the other hand, it is wholly different. The term CAM is often redefined to serve – or exclude – a specific group of individuals, therapies or products from biomedicine, and to carry different meanings for different people (e.g. chiropractic and osteopathy are sometimes, but not always, included under the term CAM) . As a result, different communities (practitioners, educators, and the public) sometimes turn to terms other than CAM to alleviate these issues, such as holistic medicine, traditional medicine, functional medicine, and most recently, complementary and integrative medicine, to name but a few.
To address these concerns, some recommend that all therapies that aim at improving the health of individuals be included under the term integrated healthcare; a term that would eliminate the terminological barriers between conventional and unconventional care. However, the terms integrative healthcare (IHC) and integration of care have emerged in parallel, adding to the confusion since there is no consensus on their definitions. Moreover, these terms are commonly used for many other purposes, which are not always associated with CAM. For example, integration of care, although no shared definition exists,  is often used to refer to healthcare services that are centrally coordinated or combined with various types of conventional care .
Consequences of plurality
Unfortunately, the plethora of terms and the lack of a consensus on definitions have several negative implications for research and clinical practice. The lack of a uniform, internationally recognized set of terms and definitions makes it difficult to compare results from different studies and to present evidence on CAM and its safe and effective application. Furthermore, the lack of consensus limits the transfer of research knowledge to health practitioners, impairing their ability to practice evidence-based medicine. The lack of appropriate terminology also renders the communication both within and among practitioners, researchers, educators, and most importantly patients, more complex and confusing. It is becoming clear, for example, that none of the terms are clearly understood by the general public . This terminological confusion has real-world consequences: it prevents effective interprofessional collaboration between conventional and CAM practitioners, which may lead to the deterioration of patient-centered care.
In 2009–2010 the research team surveyed more than 200 leaders and experts in the field of CAM or IHC using a modified Delphi survey with the goal of: 1) investigating the appropriateness of the term CAM and its definition; and 2) exploring other possible term(s) to describe what is currently referred to as CAM . The survey results suggested that although deficient, there are no alternatives for the terms CAM and IHC that can be used in both the scientific literature and public fora. The Delphi participants proposed two ways to circumvent these issues: since the CAM-related terms were found to be highly contextual (i.e. linked to research, practice, education, etc.), one needs 1) to identify the proper contexts of use in order to use the terms under appropriate circumstances; and 2) to revisit the current theoretical definitions of CAM and IHC to reflect and alleviate the concerns of academics and healthcare practitioners.
In order to explore the implications of these two propositions, we organized a two-phase consultation process in the form of a focus group of international leaders in the research and practice fields of CAM, IHC and conventional medicine, followed by an online forum, which included many more international practitioners and researchers. This paper reports on this two-phase consultation process, which aimed to clarify the contexts in which each of these terms can be used appropriately. The consensus-based definitions for both CAM and IHC are also presented.