The Four Diagnostic Methods
What Are Symptom, Pattern, Disease, and Pattern Differentiation in TCM Diagnostics?
In TCM diagnostics, “symptom” (症) refers to the individual abnormalities felt or observed, serving as the primary basis for analysis. “Pattern” (证) is the essence of a disease stage, revealing etiology, pathogenesis, location, and nature. “Disease” (病) is the entire evolution process with specific laws. “Pattern differentiation” (辨证) is the analytical thinking process that synthesizes clinical data to determine the pattern. These four concepts form the hierarchical and logical core of TCM diagnostic reasoning.
Symptom (症) refers to the abnormal changes felt by the patient themselves and the abnormal signs obtained by the physician through the Four Examinations. Symptoms are the original basis for analyzing and judging diseases and patterns, and mainly include subjective symptoms (such as headache, cough, chest oppression) and objective signs (such as pale complexion, red tongue, wiry and slippery pulse).
Pattern (证), also called syndrome, is a reflection of the essential nature of a disease at a particular stage during its occurrence and evolution. Using a set of related symptoms, it reveals, to varying degrees, the etiology, pathogenesis, disease location, disease nature, and disease tendency. It can also be considered as a delineation of the state of the body's life activities.
Disease (病) is a condition that arises under the action of pathogenic factors, involving a struggle between the body's zheng (righteous) qi and xie (pathogenic) qi, and an imbalance of yin and yang. It encompasses an entire evolutionary process with specific developmental laws, concretely manifesting in a number of characteristic symptoms and their corresponding patterns at each stage.
Pattern Differentiation (辨证) is the thought process, conducted under the guidance of TCM theory, of comprehensively analyzing clinical data to judge the pattern and provide a basis for determining treatment — that is, the process of determining to which pattern a condition belongs. It is a diagnostic method that takes into comprehensive consideration the surrounding environment, the strength of the body's zheng qi, and the characteristics of the disease.