The diagnostic criteria for chronic bronchitis should be based on the patient’s clinical symptoms, time of onset, and the exclusion of other chronic diseases that can cause similar symptoms. The diagnostic criteria of chronic bronchitis are as follows: 1. Clinical symptoms: patients with chronic bronchitis have clinical symptoms of coughing, coughing up sputum or accompanied by wheezing. 2. Onset time: chronic bronchitis patients usually have an annual onset of 3 months or more, and chronic bronchitis episodes need to be two or more consecutive years. 3. Excluding other chronic diseases that can cause cough, sputum, wheezing and other similar symptoms, such as bronchial asthma and chronic pharyngitis. An important factor in the development of chronic bronchitis is smoking, so you should actively quit smoking. If the clinical symptoms of long-term cough and sputum appear, it is recommended to consult a doctor in time and follow the doctor’s instructions to avoid delaying the condition.