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— updated 2002-10-01
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— updated 2002-10-01
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Herbalist Review, Issue 2002-#2:
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Subtopics on this page…
Abstract: advantages and capabilities of computer-aided learningSkilled practitioners of Chinese (TCM) herbology recognize the significantly greater side effects and iatrogenesis that commonly occur when Chinese herbs are recommended solely based on the medical diagnosis or the chief symptom complaint. However, due to the inadequacy of clinical analysis skills and the difficulty in teaching these skills well, many practitioners revert to this dangerously simplistic method of choosing herbs and herbal formulas. This article explores the use of computer-aided learning to develop skills in differential assessment and decision-making, which are crucial to effective clinical practice. Self-study software (TCM Herbal Tutor •[1]•) developed at the Rocky Mountain Herbal Institute incorporates computer-aided learning and interactive databases. Capabilities of such software include training users how to:
The importance of tailoring an herbal strategy to systemic-metabolic factorsThe requirement of tailoring an herbal formula to the needs of an individual's entire body is so well recognized, at least in principle, by alternative health practitioners that we need not dwell on this here, except to refer the reader to other sources that explore this idea further.•[2]• •[3]• While many people in alternative health circles, including both practitioners and their clients, give lip service to this idea, many of these people continue to ask questions as:
Such questions imply an assumption that an individual's chief health complaint can be isolated from the rest of his or her body, much as a modular unit of an automobile or washing machine can be repaired or replaced when defective. One particularly dangerous assumption is that a specific herb or nutritional factor will have only the desired, advertised effects on a target organ or body tissue, and that all other effects on other body regions and physiological processes can be safely ignored. Such assumptions often lead to the development of side effects or iatrogenic illness. For example, by focusing on the ability of ephedra to induce weight loss in many people, consumers are encouraged to ignore its often serious side effects: stress on the endocrine system, leading to adrenal exhaustion syndrome. According to the TCM materia medica it is said to easily exhaust the Qi. By focusing on the antibiotic properties of herbs like goldenseal or coptis, their tendency to impair normal gut flora and inhibit digestive function (the normal "Stomach Fire" and "Spleen Qi" necessary for breakdown and assimilation of nutrients) is often ignored until the individual experiences chronic loss of appetite, indigestion, abdominal bloating, and/or loose or watery stools. According to traditional TCM criteria, coptis and goldenseal should only be used in conditions characterized by "Interior-Excess-Heat" or "Interior-Excess-DampHeat", such conditions being defined by the presence of specific symptoms and clinical signs (pulse, tongue, etc.). •[4]• The traditional Chinese theory of syndrome pattern recognition (bian-zheng), embodies the idea that ultimately, any herbal strategy must be adjusted so as to improve total function of all physiological systems of the body, or at the very least, to minimize the damage to body systems in extreme cases requiring drastic herbs. In contrast, the idea of determining a clinical strategy primarily on the basis of the specific disease or chief complaint (bian-bing), due to its conceptual simplicity and appeal to many practitioners, has been combined with the theory of syndrome pattern recognition to embody the idea that specific diseases may manifest in a given individual as one of a small range of possible syndrome patterns. As Todd Luger has commented •[5]•, this reduces the task of clinical analysis to a simplistic type of computer flow chart, where the practitioner's job is merely to find the limited TCM syndrome possibilities for the individual's medical condition in a look-up table and decide which of the symptom-sign patterns matches most closely. This simplistic look-up table method has severe limitations, but is, unfortunately, the trend in comparative pathophysiology courses at many modern TCM schools. As an example of the preceding simplistic hybridized method, in the case of an allopathic diagnosis of hypertension, one popular textbook of herbal formulas •[6]• lists four possible syndrome (symptom-sign) patterns for the diagnosis of hypertension:
The problem is that while these aspects are indeed common in many people with hypertension, the range of actual clinical possibilities is a great deal broader. Moreover, very few people with chronic illness manifest only a single TCM syndrome; the illness commonly manifests as a complex combination of several TCM textbook patterns. For example, a specific case of hypertension might be characterized by some combination of the following:
In such cases, not one of the original four syndrome patterns applies exactly, and the herbal strategy must include aspects of several, plus additional aspects to handle factor (2), Stagnation of Liver Qi and Blood with Liver Invading Spleen. Complex clinical cases such as the preceding example are becoming common in American clinical practice, as a consequence of illness from multiple factors: atrocious diets; widespread environmental contamination, including from heavy metals; social stresses and dysfunctional family life. Simplistic look-up tables often result in clients falling between giant gaps in the data from such tables. In these cases, the practitioner may often try one standard formula after another, with unsatisfactory results, rather than using reason and logic to attempt analyzing and unraveling the problem and its various aspects. For an increasing number of cases of subclinical illness characterized by generalized debility, the medical diagnosis is not even clear, making the preceding approach irrelevant. Lacking a clear starting point in the look-up tables, one is forced back to the principle of considering overall systemic-metabolic factors to get some idea of where to begin. Unlike western medicine, in which a clear diagnosis of specific disease is necessary to determine a clinical strategy, TCM herbology provides a framework for assessing any particular manifestation of symptoms and signs, classifying the individual's condition within some region of an N-dimensional vector space that defines the total set of possibilities for systemic-metabolic characteristics. (The equivalent vector space for western medical diagnosis is filled with vast regions that are undefined and, therefore, untreatable: no known illness, yet the individual may be clearly suffering from physical and mental distress.) Another common error resulting from the simplistic look-up table method, is to ignore the effects of environment and diet on the progression of the illness and its pattern manifestations. Modern health care often requires the practitioner to assume the role of detective in uncovering and piecing together all bits of evidence for how and why the individual became ill, and removing toxic and aggravating factors. Practitioners who are trained only as clerk-technicians to look up or to memorize standard remedies in a formula catalog or textbook will be unable to fulfill this necessary role, whereas practitioners who can apply the language of TCM as a tool of complex analysis will be able to analyze their observations in ways that yield practical insights. •[7]• •[8]• Computer-aided methods for teaching skills in clinical analysis and decision-makingThe lack of effective training in critical analysis and thinking in TCM clinical work can be overcome by carefully designed computer simulations and training software. TCM Herbal Tutor •[1]•, training software developed at the Rocky Mountain Herbal Institute (RMHI), has been used by RMHI students since 1998 to assist them in analyzing complex case studies and determining herbal formulas and to train them in realistic clinical analysis and decision-making. In a paper presented at the 24th IVAS Congress in Taiwan in 1998, authors Lin, Rogers, and Yamada •[9]• discussed the need for easy access to expert information on herbal medicine to enable busy medical professionals to incorporate herbal medicine into their clinical practices. They correctly recognized that most physicians will simply not dedicate several years out of their lives to study TCM herbal medicine in the traditional manner. Among their primary recommendations were the following:
Such a database has been developed by Harvard Medical School for use in training medical students in conventional diagnosis and patient care. Similar technology is available to professionals interested in homeopathy and acupuncture, both of which western physicians also find difficult to master because of the unfamiliar underlying philosophies and the large amounts of data involved. The Self-Study Reference in traditional Chinese herbal sciences and the TCM Herbal Tutor software designed at RMHI fulfills all four of the criteria listed by Lin, Rogers, and Yamada as desirable properties of an interactive database and self-educational software in Chinese herbology. This type of computer-aided learning is radically different from the rote-memorization method of learning popular in mainland China. An interactive, cross-referenced database with a layer of intelligent logic that recognizes a user's mistakes and reminds him or her to avoid making them again is far superior to a conventional textbook or dictionary. Computer software is only as good as the algorithms programmed into its logic; it can be simplistic, just as dictionaries are simplistic and do not make stimulating or insightful reading if used exclusively as one's source of knowledge. However, computer-aided learning has recently evolved to be capable of performing and teaching the very tasks that are poorly taught by conventional methods of instruction such as listening to lectures, watching videos, most types of multiple choice quizzes, and even most textbooks; these capabilities include training users how to:
All the preceding capabilities are essential to become an effective practitioner in the real world; rarely do real people oblige us by neatly matching the tidy definitions presented in textbooks. When databases exist that possess sufficient detail, as is true of the TCM syndrome and materia medica data, then well defined procedures exist for creating database structures and computational algorithms that simulate the types of critical thinking and analysis necessary for one to successfully solve real problems. Clinical skills that can be enhanced by computer-aided instructionDistinguishing among syndromes which share one or more symptomsThe textbook definitions of each TCM syndrome generally includes a set of key symptoms and signs, of which only a subset may be present in specific cases and yet still qualify as being characterized by that syndrome. Interior Dampness vs. Deficiency of QiAs an example, Interior Dampness and Deficiency of Qi are two major syndromes that share the common symptom of fatigue, yet are very different in almost all other aspects. Interior Dampness may manifest in a wide range of illnesses from digestive disorders, chronic infections of many types, and electrolyte imbalances. Deficiency of Qi may occur in a wide range of degenerative illnesses. It is crucial to distinguish these two syndromes, as the clinical strategy and formulas for each are contraindicated in the other, though these two syndrome are relatively easy to distinguish.
If an individual presents with symptoms of fatigue, abdominal distention, and greasy-white tongue coating, the probability is still relatively high that this case is characterized by true Interior Dampness, in spite of the absence of other explicit symptoms listed in the definition. Rather than an all-or-nothing proposition, a general rule of thumb is that as a syndrome becomes more severe, a greater number of symptoms in the definition will manifest. For example, if this case of Interior Dampness with fatigue, abdominal distention, and greasy-white tongue coating becomes more severe, the individual may begin to suffer from oppressive distended pains in the abdomen and/or chest, depending upon the specific domain or Organ in which the Dampness is localized. The question often arises of how much or how little information is adequate for reliably determining that a syndrome is present in a given case. The problem with this question is that it assumes a simple answer, yet the correct answer depends not only upon the particular syndrome, but also upon other syndromes which may share symptoms and signs with it, and among which it is clinically important to distinguish. For example, while fatigue is a common symptom of general Deficiency of Qi, it is an erroneous to assume that fatigue is likely to indicate Deficiency of Qi and to forget the possibility that Interior Dampness may also result in fatigue and lethargy. Yet a cursory comparison of these two syndromes reveals that in almost all other details, Deficiency of Qi is very different from Interior Dampness. One must also consider that in a given case, it is quite possible to have varying degrees of both Deficiency of Qi and Interior Dampness simultaneously, if evidence of both is present. For example, a pale tongue, fatigue, weakened pulses, and greasy white tongue coating strongly suggests that both syndromes are present, and each syndrome contributes to the symptom of fatigue. Interior-Excess-Heat vs. Deficiency of YinInterior-Excess-Heat and Deficiency of Yin (Interior-Deficiency-Heat) are two syndromes that many practitioners find difficult to distinguish correctly. (Both patterns are common in infectious feverish illnesses; Deficiency of Yin tends to occur more in the advanced, or chronic phases of such illnesses, as well as in other conditions characterized by systemic dehydration.) These two patterns share over 12 symptoms and signs, yet it is crucial to distinguish between them, as the herbal strategy for each is contraindicated in the other. In the following table, distinguishing symptoms are italicized.
Correctly identifying subsets of the preceding lists of symptoms as being more likely associated with one or the other syndrome is a challenging task and is a fundamental skill of clinical health assessment or diagnosis. Unfortunately, many TCM textbooks present the syndrome definitions without much discussion of differential assessment techniques, leaving the clinician to his or her own wits when a case does not closely match the textbook pattern. The TCM Herbal Tutor software teaches skills in matching subsets of symptoms and signs with likely syndromes by exhaustively presenting possible combinations, permutations, and subsets of common symptoms and signs and requiring the user to identify which syndrome or syndromes are possible matches. Moreover, the user is required to identify when there is not yet enough information to reliably distinguish among several syndromes. Analyzing complex cases with multiple patterns: example case of advanced breast cancerTo analyze cases characterized by the simultaneous presence of multiple syndromes requires that practitioners have the ability to recognize subsets of symptoms and signs that reliably indicate the presence of single patterns. The following summary of a case of breast cancer •[10]•, typical of many complex cases, illustrates the difficulty in performing this task:
As an example of how one would go about systematically evaluating the evidence, consider the possibility of Deficiency of Qi in this case: Deficiency of Qi: fatigue; voice quality low, soft, and slow; tongue tissue pale, and thin; tongue coating very thin, white; pulses generally weakened; L1, R1, R3 pulse positions are weakened-wide-fuzzy in quality; hypothyroidism. It is clear that there are enough symptoms and signs to reliably determine that Deficiency of Qi is present with a high degree of certainty, and, moreover, that the Deficiency of Qi is relatively severe. However, there are many other syndromes simultaneously present. When all the symptom-sign evidence is analyzed, it becomes clear that multiple types of Deficiencies and Excess qualities are present (numbers indicate relative magnitude estimates from 1 to 7):
To design an optimal strategy and formula for such a case goes far beyond the capabilities of the simplistic look-up tables that may be found in comparative pathophysiology textbooks under the rubric "breast cancer". For a complete analysis of this case, see reference •[10]•. The Boolean search capability of the TCM Herbal Tutor software allows the user to key in specific subsets of symptoms and signs and then to search for the most likely syndromes that include these symptoms and signs. In this manner, each syndrome component of a complex case may be explored individually. For a complex case such as the preceding one, it is recommended to break down the analysis to consider only one syndrome at a time and the subset of symptoms and signs providing evidence for it. When the user understands a component well, then he or she may proceed to the next syndrome for analysis. Overcoming the rigid thinking induced by hierarchical classes of information (most textbooks)By their nature, printed textbooks are constrained to present data in hierarchical manner: each piece of information must be classified and pigeonholed into a specific chapter and subsection. The problem is that real life is multi-dimensioned and interrelated in complex ways that defy such tidy classifications. As an example of this problem, consider that one has assessed an individual as having Deficiency of Yin of the Lungs and Kidneys. Most practitioners will, logically enough, begin searching for possible herbs under the heading "Tonify Yin herbs". However, many herbs and herbal formulas have multiple properties, and some of these properties may logically fall under different chapter classifications. Herbs that tonify or moisten Yin may also be found under the following categories:
Using only a textbook, to find all relevant herbs one must exhaustively search each chapter. Relational databases, in contrast to printed textbooks, can easily provide access to all herbs possessing certain qualities, regardless of their primary classification. The cross-referenced databases in RMHI's Self-Study Reference and the TCM Herbal Tutor provide multiple ways to access information using a combination of methods from simple cross-referencing to advanced Boolean search algorithms. Multiple search criteria for herbs and formulas may be specified, commanding the software to search for and display all entries with the desired properties. A similar problem arises in performing assessment of a clinical case, in which a few symptoms are present that seem to be consistent with a specific pattern. However, to increase one's certainty of being correct, all patterns that include the specified symptoms should be considered and compared. If necessary, additional questioning regarding symptoms may be necessary to rule out several possibilities. This type of differential assessment or diagnosis is a central feature of all scientifically based health systems, and the logical demands of such a process often exceed the current skills of many who are not trained in some field of scientific medicine. Both the advanced Boolean search capabilities and the self-quizzing features of the TCM Herbal Tutor software helps develop these logical skills by presenting the user with groups of symptoms and signs, which may or may not uniquely point to a specific TCM syndrome; the user's task is to determine whether the information is adequate to make an assessment and, if so, to specify the syndrome correctly from among a group of similar or closely related syndromes. There is an inevitable tendency, while studying and memorizing syndromes, herbs, and formula information, to dwell on certain easily recognized features, odd phrases, or unusual facts. Flash-card type learning, while having limited utility, suffers from this defect. The problem is that real life may not present us with the same odd details we may have memorized, to the detriment of more obscure or mundane details. The self-quizzing modules of the TCM Herbal Tutor overcome this limitation by continually presenting the data in varying permutations, combinations, and contexts that demand the user's attention to details he or she may have otherwise ignored. By keeping track of the user's performance, the software continues to quiz the user on items and knowledge categories requiring more practice. Examples of practical, clinical problems that can be easily answered using databases with Boolean search capabilityFollowing are common types of clinical problems and questions that are often tedious to answer using most conventional textbooks, yet are easily solved using searchable databases:
SummaryInteractive relational databases and self-quizzing software that simulates realistic clinical decision-making provide new and better options for learning difficult subjects like Chinese herbology. Answers to specific clinical problems can be accessed quickly, freeing up time for busy clinicians to focus on the more important task of understanding and solving people's health problems. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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