In Chinese medicine, doctors use various methods to get full and detailed information about the patients and to guide their treatment. They observe, listen, smell and touch. They also talked to the patients or their relatives. To treat the diseases, they use the methods of observation, auscultation and olfaction, interrogation, and pulse feeling and palpation. These methods, known as the four major methods, each have their distinctive function and doctors can make a correct analysis of the diseases by applying all of them.

Observation
To observe, it is believed that people's outer appearance is closely linked with their internal organs. If there is something wrong with the internal organs, such changes will be reflected in their expressions and appearance. Therefore by doctors can analyze the changes of the internal organ by observing the outer appearance.

Auscultation and Olfaction
By methods of auscultation and olfaction, doctors try to diagnose the disease by listening to the sound of the patients and smelling the odor of excreta released by human body.

By listening to the sound of the patients, doctors can not only detect the changes of the organs related with sound, but also changes of other internal organs. The sounds include: speech sound, respiring, coughing, haw and belch.

Also, doctors can smell the odor released by patients. It is believed that when viruses attack human body, people's internal organs and blood will be affected, thus their body fluid and excreta will release bad smell.

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Interrogation
By interrogation, doctor will talk to the patients or someone who know the diseases to get the information about how the disease occurs, how it develops, its current symptoms and how it is treated. This method is useful when there are no obvious symptoms from the patients' outer appearance. In this case, interrogation will help the doctors to get the information they need. Also, by interrogating, doctors can obtain other indirect information related with the disease, such as the patients' daily life, working environment, food preference and marriage status.

Pulse Feeling and Palpation
Doctors use the method of pulse feeling and palpation by touching or pressing the patient's pulse. It is believed that changes inside the body are reflected by the changes of the pulse activity. Sometimes doctors press the skin of certain part of the body to identify the nature and the severity of the disease inside certain part of the body.