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Definition: Lung Function Tests

Lung Function Tests

The term "lung function" refers to how well a person is breathing. There are several tests that help doctors find out how good a person's lung function is and determine whether the person has asthma. One of these tests, called a spirometry test, involves taking a breath and then blowing the air out as fast and as long as possible. Lung function tests can help a doctor find out if someone has asthma.