Chinese medicine has three methods for staging an acute fever. The six stages (liujing bianzheng, 六經辨證) come from the Shanghan lun, the Treatise on Cold Damage of Zhang Zhongjing. The four levels of defence, qi, nutrient and blood (wei qi ying xue bianzheng, 衛氣營血辨證) come from the warm disease school of the Qing physician Ye Tianshi, and the three jiao (sanjiao bianzheng, 三焦辨證) from the later physician Wu Jutong. Each divides the course of the illness into stages and says where in the body it has reached at each. The WHO’s 2007 standard terminology for traditional medicine in the Western Pacific defines all three, and its successor, the 2022 WHO terminology for traditional Chinese medicine, defines them again in shorter form.
The six stages
The 2022 terminology defines six-meridian pattern differentiation as a method Zhang Zhongjing developed for externally contracted conditions, organised by the six channel names of the Huangdi neijing. The 2007 terminology says it was applied to acute febrile diseases at their different stages, and adds that it is also useful for other diseases. Each stage carries the name of a pair of channels, which the 2007 terminology lists. The channel system, counted places those channels among the fourteen.
| Stage | Chinese | Channels | What the 2007 terminology describes |
|---|---|---|---|
| Taiyang, greater yang | 太陽 | Bladder, small intestine | The onset of a febrile disease: headache, a painful stiff nape, aversion to cold and a floating pulse |
| Yangming, yang brightness | 陽明 | Large intestine, stomach | Exuberant yang and dryness-heat in the stomach and intestines: abdominal distension with constipation, tidal fever, a deep replete pulse |
| Shaoyang, lesser yang | 少陽 | Triple energizer, gallbladder | The pathogen between exterior and interior: fever and chills that alternate, fullness in the chest and ribs, a dry throat and a string-like pulse |
| Taiyin, greater yin | 太陰 | Lung, spleen | Declining spleen yang with cold-dampness: poor appetite, vomiting, abdominal fullness and dull pain, diarrhoea, a weak pulse |
| Shaoyin, lesser yin | 少陰 | Heart, kidney | A late stage, with deficiency cold of the heart and kidney: aversion to cold, listlessness, cold limbs, diarrhoea with undigested food, a fine pulse |
| Jueyin, reverting yin | 厥陰 | Pericardium, liver | The last of the yin stages, in a critically ill patient, with cold and heat, or yin and yang, interwoven |
The stages also have sub-patterns. Taiyang has a channel pattern and a bowel pattern, in which the pathogen reaches the bladder, and yangming has a channel pattern of high fever and sweating and a bowel pattern of heat lodged in the stomach and large intestine. The 2007 terminology defines several ways a disease moves between stages. In sequential transmission it passes from taiyang to yangming, shaoyang, taiyin, shaoyin and jueyin in that order; in skipping transmission it jumps one or more, as from taiyang straight to shaoyang; and in a direct strike the pathogen attacks the three yin channels without passing through the yang ones first.
The four levels and the three jiao
The four-level method sorts epidemic febrile diseases by depth. In the 2007 definitions the defence level (wei) is the initial stage, with fever, slight aversion to wind and cold, headache, a red tongue tip and a rapid floating pulse. At the qi level (qi), the second stage, heat has entered the yangming channel or the lung, gallbladder, spleen, stomach or large intestine, and the patient has high fever without chills and strong thirst. At the nutrient level (ying) heat disturbs the heart and mind, the fever is higher at night and the tongue is crimson; the blood level (xue) is the severest stage, with bleeding, high fever, coma or convulsions. The 2022 terminology says the four levels indicate the depth, severity and transmission of epidemic febrile diseases, and defines non-sequential transmission: a pathogen that skips the qi level and passes straight from defence to nutrient and blood, which it says often indicates a more severe condition.
The three jiao divide the same diseases by region. The 2022 terminology credits the method to Wu Jutong (1758 to 1836) and assigns the upper jiao to the lung and pericardium, the middle jiao to the spleen and stomach, and the lower jiao to the liver and kidney. In the 2007 definitions the upper jiao pattern belongs to the early stage of an epidemic febrile disease, the middle jiao to the middle stage and the lower jiao, with damage to liver and kidney yin, to the later stage.
Where the methods came from
Jean-Claude Dubois, in a 2020 history of epidemic disease in Chinese medicine, dates Zhang Zhongjing to around AD 150 to 219 and calls his treatise the oldest Chinese work on the therapy of febrile illness. Zhang’s original, the Treatise on Cold Damage and Miscellaneous Diseases, was rearranged by Wang Shuhe (265 to 316), who gathered its first ten volumes as the Shanghan lun; the rest was assembled in the Song dynasty as the Jingui yaolue, the Synopsis of the Golden Chamber. The classical texts places both among the other classics.
Dubois describes the warm disease school as a response to epidemics that Zhang’s method did not handle. When an epidemic struck four provinces in 1641, Wu Youxing found doctors repeating Zhang’s prescriptions while people died by the thousand, and wrote his Treatise on Pestilence, which the 2007 WHO list of classics dates to 1642. Ye Tianshi (1667 to 1746) did not write his method down himself: his disciples recorded his teaching as the Wenre lun, the Treatise on Warm Heat Disease, and Dubois writes that the four levels suit heat-type infections better than the six stages. Wu Jutong then added the three jiao in his Wenbing tiaobian of 1798, the Systematized Identification of Warm Diseases. Dubois also writes that the four levels are no more anatomical than the six channels.
The two schools are not the whole tradition. Peng Jian, in a 1999 history of these diagnostic systems, calls the six stages, the four levels and the three jiao the most famous but not complete, and names two further systems from physicians of the Jin to the Qing dynasties, among them Liu Hejian. Japanese Kampo medicine rests on the Shanghan lun: Yakubo and colleagues describe how Kampo physicians of the 17th and 18th centuries set aside Ming-dynasty theory to return to the Shanghan lun, and report that Kampo today uses its six stages for acute febrile infections such as influenza and patterns of qi, blood and fluids for chronic disease.
The eight principles and the organs
The 2022 terminology states that the three yang patterns often manifest as heat and excess, from a fierce struggle between the body’s anti-pathogenic qi and the pathogen, and that the three yin patterns often manifest as cold and deficiency, from weakness of the anti-pathogenic qi. Shaoyang occupies the half-exterior, half-interior position that The eight principles describes between exterior and interior. The organs come in as a disease deepens: the bladder in the taiyang bowel pattern, the stomach and large intestine in yangming, the spleen in taiyin, the heart and kidney in shaoyin, and in the three jiao the lung, spleen, stomach, liver and kidney. The zang-fu organs describes the organ patterns on their own terms.
The frameworks also meet each other. Zhang Hui, in a 2023 article on defensive qi, reads a taiyang disorder in the six-stage system as a disorder of the defensive qi, and places the defence level of the four-level model at the early stage of fevers from heat pathogens, giving influenza, pneumonia and Covid-19 as examples.
How acupuncture uses them
The Shanghan lun is mostly a book of herbal formulas, and its acupuncture passages are few. Zeng Zhiying and colleagues, in a 2010 analysis of those passages, draw out five features, among them needling to cut off the pathogen’s route and stop a disease progressing, combining acupuncture with herbs, and a view that the yang channels suit acupuncture while the yin channels can also be used. Bian Dong and colleagues, in a 2018 study, report that the point Zhang used most often in the book is LV14 (Qimen), the front-mu point of the liver channel.
Modern authors assign points to the patterns as they assign formulas. Zhang Hui’s 2023 article pairs cold blocking the defensive qi, which it treats with Mahuang tang, with LI04 (Hegu), TB05 (Waiguan), GV14 (Dazhui) and BL11 (Dazhu), BL12 (Fengmen) and BL13 (Feishu). For wind attacking the defensive qi, treated with Guizhi tang, it gives GB20 (Fengchi), TB05, LI04, KD07 (Fuliu) and ST36 (Zusanli). For wind-heat at the defence level of a warm disease its points include LI11 (Quchi) and points of the lung channel, and it recommends bleeding LU11 (Shaoshang) when the patient has a sore throat and high fever. These are one practitioner’s selections, published as teaching, not trial results.
What research has tested
The studies this page draws on examine the text or propose links to modern diagnoses. Shao and colleagues built a network model of the symptoms, formulas and herbs in the Shanghan lun in 2016, split it into six subnetworks, one per stage, and found taiyang and yangming the most strongly related. Wang and colleagues, in a 2026 review, map the four levels onto the stages of dengue fever and its biomarkers. They report that the few clinical studies of the related formulas need validation, that several of the mechanisms they propose are extrapolated from models of other diseases, and that their framework is meant to generate hypotheses, not to serve as a validated treatment algorithm.
None of the sources here measures whether two practitioners assign the same stage or level to the same patient. The four examinations collects the agreement studies on pattern diagnosis in general, which report low to moderate agreement.
What AcuiQ records
A published prescription in AcuiQ’s index records the condition and, where its authors gave one, the pattern they reached. It does not record whether they staged the illness by the six stages, the four levels or neither, and AcuiQ does not check the staging behind a prescription that names one.