Final answer:
A negative methacholine challenge test can help exclude a diagnosis of asthma in a patient with intermittent shortness of breath.
Step-by-step explanation:
A negative methacholine challenge test can help to exclude a diagnosis of asthma in a patient with intermittent shortness of breath. Asthma is a chronic illness characterized by the inflammation and narrowing of the bronchioles, leading to difficulty breathing and wheezing. By performing a negative methacholine challenge test, which measures the sensitivity of the airways, healthcare providers can determine if asthma is the cause of the patient's symptoms.