Lung function tests, also called pulmonary function studies, include a variety of tests that check how well the lungs work. Tests include:

• Spirometry – measures the amount of air the lungs can hold and how forcefully one can empty air from the lungs
• Lung Volume Testing – measures the volume of air in the lungs, including the air that remains at the end of a normal breath
• Diffusing Capacity – measures how easily oxygen enters the bloodstream
• Exercise Testing – used to evaluate causes of shortness of breath