A Study on the Diagnostic Value of the Methacholine Choline Provocation Test in the Asthmatic Population

Inclusion Criteria: Stage I study:

• clinically evaluated as suspected asthma but have not been previously diagnosed asasthma and require a bronchial provocation test
• Basal lung function FEV1 ≥ 60%
• Meet the requirements for conducting bronchial excitation tests and pulmonaryventilation examinations
• Not currently suffering from or accompanied by other respiratory diseases, includingallergic rhinitis, chronic obstructive pulmonary disease, chronic bronchitis, etc. Stage II study:
• Basal lung function FEV1 ≥ 60%
• Meet the requirements for conducting bronchial excitation tests and pulmonaryventilation examinations

Exclusion Criteria:

• Have had a fatal asthma attack, or have required mechanical ventilation for an asthmaattack within the last 3 months
• Definite hypersensitivity reaction to inhaled stimulants or salbutamol or unexplainedurticaria
• Severe impairment of basal pulmonary ventilation (FEV1 < 60% of expected value %, or < 1 L in adults)
• Poor cooperation with basal pulmonary function tests that do not meet quality controlrequirements
• Other conditions that make a bronchial provocation test or pulmonary ventilationfunction test inappropriate (e.g., recent presence of severe cardiovascular disease,seizures, uncontrolled hypertension, etc.)