Eight Principles Pattern Analysis in TCM

What the Eight Principles are

The Eight Principles (sometimes called the Eight Guiding Principles) are a way of organizing a traditional Chinese medicine (TCM) pattern. One paper lists them as yin, yang, exterior, interior, cold, heat, deficiency and excess. [1] Another explains that six of them (exterior, interior, cold, heat, deficiency and excess) are concrete patterns, while yin and yang are higher concepts that encompass the other six. [2]

These are traditional framework terms, not measurements. "Cold" or "heat" here are categories of a pattern in TCM, not body temperature or fever. For the ideas behind yin and yang, see Yin and Yang in Chinese Medicine.

The three pairs

The six concrete patterns are grouped into pairs of opposites: exterior and interior, cold and heat, deficiency and excess. [2] Traditionally, the three pairs describe how far an external pathogen has penetrated the body, the nature of the disease, and the relative strength of the body's resistance against the pathogenic factor. [2] In this vocabulary:

• Exterior and interior are the first pair.
• Cold and heat describe the character of the pattern. A rheumatoid arthritis study describes heat as belonging to yang and cold to yin. [1]
• Deficiency and excess compare the person's resistance with the pathogenic factor. [2]

How these terms are applied to a given person is a practitioner's judgement from the findings of the four examinations; see The Four Examinations. We do not provide a checklist for placing yourself on these scales.

How the Eight Principles relate to other methods

The Eight Principles are described as the most comprehensive type of pattern identification. [2] Practitioners also use other frameworks, including organ-based patterns; see Zang-Fu: The Organ Systems of Chinese Medicine and Common TCM Patterns Explained. Plain-language meanings of cold, heat and dampness are in Cold, Heat, Dampness, Phlegm: Common TCM Terms Explained.

What research shows

An Australian study had three practitioners assess 45 adults with mild high cholesterol who were otherwise healthy. The authors reported reasonably good agreement between at least two practitioners on the dimensions of the Eight Guiding Principles, but agreement on organ-based syndromes was very good for only one, Spleen qi deficiency. [3] They called for more research on the diagnostic process. [3]

Other studies of TCM patterns generally found poor agreement; for example, eight acupuncturists diagnosing 25 women from case histories showed kappa below 0.20. [4] A review concluded that studies of pattern diagnosis had not generally found a high level of reliability. [5]

Evidence label: mixed to limited. Broad dimensions such as the eight principles appear to be agreed on more often than fine-grained patterns, but this rests on one small study. We did not find a trial showing that treatment chosen by the Eight Principles gives better outcomes: proper evidence not found.