What is the definition or description of: pulmonary function test?

Lung function tests: Pulmonary function tests is a term used to describe a group of tests done to determine lung function. Spirometry measures the amount of air that can be taken in as well as the flow rate of forcefully exhaled air . A graph is generated and can be used to determine lung function. Likewise lung volumes and diffusing capacity determine the capacity as well as the oxygen exchange function.