Pulse diagnosis and tongue diagnosis are widely used in traditional Chinese medicine. They are based on imagination, not on anatomical and physiologic reality.
History of pulse diagnosis
Pulse diagnosis was an important part of ancient medicine in Egypt, Greece, India, Tibet, and elsewhere. The specific methods used were ambiguous and varied widely from place to place, making them extremely difficult to test.
Ancient physicians didn’t have EKGs or even a stethoscope. The pulse was one of the only diagnostic tools available to them. They tried to use the pulse to diagnose heart, liver, renal, and gastrointestinal problems, with varying degrees of success. The pulse can indeed offer clues, but today we have much more effective ways of reaching a diagnosis.
Reality-based pulse diagnosis
In mainstream medicine, a complete physical exam has always included palpation of arterial pulses, observing the intensity, rate, rhythm, and whether any blood vessel tenderness, tortuosity, or nodularity exists. Two qualities are objective and can be confirmed by EKG: the rate and the rhythm. Arrhythmias like paroxysmal tachycardia, premature ventricular contractions (PVCs), and atrial fibrillation can be detected. In pulsus paradoxus, the rate slows with inspiration; it is found in several conditions such as pericardial effusion, pneumothorax, and chronic obstructive pulmonary disease (COPD).
The other qualities are more subjective, but can be confirmed more objectively by pulse wave analysis with instruments. A weak pulse is an indication of impaired blood flow; a thready, rapid pulse is present in shock; a “water hammer” collapsing pulse suggests aortic insufficiency; a rapid, snapping pulse suggests thyrotoxicosis; a rock-hard artery reveals calcified atherosclerosis; pulsus alternans (alternating strong and weak beats) indicates left ventricular dysfunction. The radial artery pulse at the wrist is most commonly used, and is adequate for assessing rate and rhythm; but it is not the best artery to indicate pulse character. Comparison of pulses in various locations can help diagnose several conditions where there is anatomical obstruction to flow.
Chinese pulse diagnosis is not reality-based
Chinese pulse diagnosis is something else entirely. Dr. Hammer, founder of the Shen-Hammer system aka Contemporary Chinese Pulse Diagnosis (CCPD) explains (emphasis added):
Of all diagnostic modalities, the pulse can give us the most precise picture of even the most subtle and complex deviation from this standard of health. The pulse record is an instant picture of the current status of a person’s voyage from birth to death. Clinically, it preserves us from the distraction and fruitless pursuit of symptoms, and keeps us focused on the reality of the individual’s condition and being.
In addition, the pulse gives information about the events in a person’s life that create this deviation from the Normal, allowing our patient the opportunity to change his life and habits, or adapt to constitutional deficits in the direction of health. The precision of the diagnosis permits a rational therapeutic regime for the patient and is a tool for prognostication and prevention.
When practiced with dedication, quiet patience and consistency, becoming attuned to pulse qualities is an ongoing meditation, a training ground for awakening and awareness into total focus and concentration. As such, pulse diagnosis is an opportunity for practitioners to obtain the ultimate satisfaction of being one with their patients, one with themselves, one with the diagnostic process, and perhaps one with the universal forces that are expressed through the pulse.
In the late 1950s, the Chinese government set up an experiment in which many well known masters of Chinese pulse diagnosis were asked to examine a patient. Their findings varied widely, and as a result pulse diagnosis was judged to be an unreliable scientific diagnostic tool. Others have questioned its reliability because of the wide variety of pulse methods within the Chinese tradition, and especially between the Chinese and other pulse systems used by other cultures, such as the Tibetan and Ayurvedic systems, in which the positions are in great variance from the Chinese. What is difficult to contemplate and absorb is that each of the Chinese masters who failed the government test as well as each different pulse system is correct, providing not contradictory information, but different information.
In other words, everything about Chinese pulse diagnosis is considered to be correct, and there would be no way to prove anything wrong. This makes it unfalsifiable, and puts it outside the scientific paradigm.
One of Hammer’s disciples says:
What I am most impressed with and most try to emulate is Dr. Hammer’s ability to understand his patient’s suffering and perception of his/her illness, his ability to make contact with patients and enter into a sacred therapeutic relationship. The pulse is a tool for this process and informs the diagnoses, and acts as a catalyst or jump start in the formation of this healing relationship.
He is talking about bedside manner and the nonspecific therapeutic effect of the doctor/patient relationship. Contextual effects and suggestion are a big part of what has been called the placebo effect. Of course a patient will feel better after he has had so much attention lavished on him, along with an explanation by a charismatic “expert.” And the long observation time gives the doctor a chance to observe lots of other things about the patient and perhaps even to do some cold reading.
The apparent success of pulse diagnosis can be attributed to factors that have nothing to do with whether the diagnosis is correct by any objective standard, or whether clinical outcomes are improved more than could be achieved by a theatrical placebo.
Contemporary Oriental Medicine
Contemporary Oriental Medicine (COM):
includes over 100 unique concepts not included in TCM. Concepts that reflect the realities of Chinese medicine as an evolving medicine relevant to the present day and age. Such concepts include: birth traumas and Heart shock, toxicity, Liver qi and yang deficiency, the separation of yin and yang as precursors to significant and debilitating illnesses, etc.
COM is a creation of Dr. Hammer. The COM Foundation website says, “At first glance, it may appear to be a singular, personal perspective…” Yes, and after careful consideration it still appears to be one man’s idiosyncratic creation. He says it is “the true embodiment of tradition, seamlessly blended with modern insight and wisdom [not with modern science].” It “encompasses a modern, 21st century perspective on medicine and health.” It “stresses psychology, along with a methodology for thinking in Chinese medicine, and integrates parts of various models including TCM and Five-Element into a unique whole.” That’s all very nice, but is there any evidence that his methods are valid and have any objective effect on patient health outcomes? No, there has been no validation. He believes in what he’s doing, but he doesn’t see the need to test it.
Contemporary Chinese Pulse Diagnosis (CCPD)
CCPD is predicated on the belief that the radial artery represents the health of the person. It incorporates eight depths, but in practice only three are used. The qi and blood depths represent an organ’s contribution to these substances within the whole organism and the organ depth relates information regarding the organ parenchyma.
It uses 28 pulse positions on the radial artery to determine the presence or absence of 80 pulse qualities. The positions relate to various organs, as seen in this diagram:
Good grief! This is just another imaginary homunculus-type diagram detailing nonexistent connections between one body part and other parts of the body. The homunculus model is a prescientific notion of biology that has no basis in anatomy, physiology, or any other basic science. Bogus homunculus diagrams are found in iridology, acupuncture, reflexology, and many other pseudoscientific belief systems. They are so prevalent that John McLachlan satirized them in his “butt reflexology hoax” which he described in an article for the British Medical Journal; he had invented an inverted homunculus on the buttocks and had been invited to speak at a conference about his “research.”
There are six basic positions and 22 complementary positions in CCPD. The complementary positions are yang, so the three depths of the yin organ system don’t apply.
CCPD encompasses 80 pulse qualities. In an attempt to eliminate the metaphoric ambiguity of the classical literature, Hammer describes them according to sensation, using “modern language.” It doesn’t sound like modern language to me, and it clearly isn’t scientific language.
- Volume: a reflection of metabolic activity or the strength of qi or yang heat within the body.
- Depth: provides information regarding the location and stage of the disease; superficial pulses are associated with acute disease involving the wei qi
- Width: reflects the condition of the blood
- Length: used to classify conditions of plentiful qi or deficient and stagnant qi
- Shape: reflects excesses or deficiencies of certain substances. Divided into Fluid, two kinds of Nonfluid, and Miscellaneous
- Other categories: modifiers and anomalous
There are detailed procedures of palpation involving one or more fingers on one or both sides of the body.
Evaluating CCPD with science
One of the first questions to ask is whether the pulse findings are reliable. Is there intra- and inter-observer consistency? In other words, if an examiner repeats the exam on the same patient, does he get the same findings? If multiple examiners examine the same patient, do their findings agree? As mentioned above, previous studies had shown pulse diagnosis to be unreliable. Is this new version, CCPD, more reliable?
Karen Bilton tried to answer that question with a study reported in her thesis submitted as partial requirement for the degree of Doctor of Philosophy at the University of Technology in Sydney. The title is “Investigating the reliability of Contemporary Chinese Pulse Diagnosis as a diagnostic tool in Oriental medicine.” Bilton’s credentials include physiotherapy, acupuncture, and Chinese herbal medicine, and she has been studying pulse diagnosis under Leon Hammer, the originator of CCPD, for the last 15 years. That suggests she is a true believer with a strong bias in favor of pulse diagnosis.
The task she embarks on is an impractical, quixotic one. She is using the methods of science to evaluate something that is not based on science or reality, something that involves an unmanageable number of variables.
In reviewing the literature for previous studies, she found that:
- With increasing complexity of the pulse variable being detected, levels of both intra- and inter-rater agreement decrease.
- Inter-rater reliability decreases as the number of pulse testers increases
Well, duh! Isn’t that exactly what you would expect for a made-up method that relies mainly on subjective assessments?
She thought she could do better, so she designed what she thought was a more rigorous test with better defined parameters. Talking was not allowed, and the testers were blinded to each other’s findings. Subjects remained in view of the testers. Open testing conditions were employed, since “reliability… was the exclusive interest of the study, and not validity.” She wants to know whether the results agree, not whether they’re valid. The term “validity” means the extent to which a measurement corresponds accurately to the real world. I don’t think the devotees of CCPD want to live in the real world.
There were 15 subjects and six testers. The study was carried out at Dr. Hammer’s Dragon Rises College of Oriental Medicine in Florida. One of the testers was apparently Dr. Hammer himself; the others had studied with him for 8-10 years and had been teaching the system themselves at his college for more than three years. For each subject, four pulse rates and 30 pulse categories were collected on two occasions. There were 76 pulse qualities. For the large segment of the pulse there were 11 pulse categories, each with anywhere from 4 to 51 variables. She had a lot of data to work with; she made 11,760 kappa calculations! She found excellent to good agreement in 67% of intra-rater comparisons and 44.1% of inter-rater comparisons. Reliability was less for the pulse qualities of Muffled, Change of Amplitude, Blood Heat, Blood Thick, and Flooding Deficient. For the Combined Complementary Positions, there was unacceptable reliability. She suggests that if the definitions for those pulse qualities and positions were modified, the reliability would improve. I suggest that they should be discarded rather than re-defined, because they are not meaningful measures of anything.
Her write-up is tedious, packed with excruciating details, and trying to read it gave me a headache. I won’t even try to comment on the validity of her statistical analyses, except to say that calculating kappa for 11,760 different comparisons must have broken some kind of record! The whole enterprise was misguided. At least she admits that the validity of using pulse information to guide diagnosis remains questionable.
What have we learned from these experiments? For objective variables like pulse rate and rhythm, anyone who can count and read a clock would be expected to get very reliable readings. For many of the more subjective variables, it would be expected that this very inbred group of testers, who all had the same training, indoctrination, experience, and constant contact with each other, would have been trained to report similar findings whether they were real or not. So I don’t think we have learned anything meaningful. In fact, the whole dissertation reminds me of what Richard Feynman called cargo cult science, where it looks like science and talks like science but doesn’t really understand how science should work. Science doesn’t deal with claims that are unfalsifiable, and Hammer’s claims for CCPD put it outside the realm of science.
Practitioners of pulse diagnosis are frequently also practitioners of tongue diagnosis. Here we go again! They claim tongue diagnosis is an effective method used to diagnose diseases. They claim that different regions of the tongue represent different parts of the body, internal organs, and “channels.” From front to back, areas of the tongue represent the heart, lungs, stomach and spleen, large and small intestines, kidneys and bladder; the sides of the tongue represent the liver and gallbladder. How do you suppose they figured that out?
There are eight tongue feature indications:
- Tongue Body Color
- Tongue Body Shape
- Tongue Body Features
- Tongue Body Moisture
- Tongue Coating
- Tongue Coat Thickness
- Tongue Body Cracks
- Tongue Coat Root
There are elaborate categories under each of these tongue features. For instance, the Tongue Body Shape can be Stiff, Flaccid, Swollen, Big or Enlarged Tongue, Half the Tongue is Swollen, Hammer Shaped, Local Swelling on One Side, Swollen Sides, Swollen Between the Tip and the Central Surface, Swollen Edges, Swollen Tip, Short and Contracted, Long, Front Swollen, and Thin. And there are details under each of these. For instance, if the tip of the tongue is swollen, it usually indicates heart problems; if it is also deep red, this may indicate Heart Fire; and if it is normal in color or pale, this may indicate Heart Qi Deficiency. A yellow tongue coat indicates Wind-Heat or Wind-Cold turning to Wind-Heat. This is all very imaginative, but it is completely divorced from any anatomical or physiological reality.
Reality-based tongue examination
In conventional medicine, inspection of the tongue is an integral part of the physical exam and can provide clues to many diseases. Some examples: A smooth tongue may be caused by dentures, certain nutritional deficiencies, or glossitis. A geographic tongue, with discolored, painless patches, is a benign condition seen in 1-3% of the population. A hairy tongue is a sign of EBV infection in HIV-positive individuals, and a black hairy tongue can be due to an overgrowth of the fungus Aspergillus in patients on chronic antibiotic treatment. Longitudinal furrows can result from syphilis. Ulcers can be benign or a sign of systemic illnesses or cancer. Fasciculations indicate lower motor neuron injury and may be a sign of amyotrophic lateral sclerosis.
Scientific assessment of reliability
In a 2008 study, TCM practitioners were shown photos of tongues and filled out questionnaires. There was very poor inter- and intra-practitioner reliability even for simple dichotomous choices.
Conclusion: based on imagination, not reality
On Quackwatch, Stephen Barrett wrote an article titled “Why Traditional Chinese Medicine Diagnosis Is Worthless.” He concluded:
TCM theory and practice are not based upon the body of knowledge related to health, disease, and health care that has been widely accepted by the scientific community. TCM practitioners disagree among themselves about how to diagnose patients and which treatments should go with which diagnoses. Even if they could agree, the TCM theories are so nebulous that no amount of scientific study will enable TCM to offer rational care.
I agree wholeheartedly. Chinese pulse diagnosis and tongue diagnosis are based on imaginary concepts, not on reality. If they want to bring them into the real world of science, perhaps the place to start would be to pick just one of the spots on the wrist or tongue that are said to represent a given organ and test whether that claim is true. It would be interesting to learn how the connection was first proposed and whether it was ever confirmed by testing. (Hint: it wasn’t.)
This article was originally published in the Science-Based Medicine Blog.