Lung function tests, which are also called pulmonary function tests are tests that can be carried out to find out how well your lungs and airways are working. Lung function tests can assist in the diagnosis of respiratory (breathing) conditions, they can also work out how severe a condition is, and help monitor the response to treatments.
Lung function tests are often used to help diagnose or assess asthma and chronic obstructive pulmonary disease (COPD). They are also used to assess other conditions that affect breathing, including lung scarring and illnesses that affect the chest or breathing muscles.