FEV1predicted

FEV1 predicted refers to the expected or normal value of Forced Expiratory Volume in one second (FEV1) for a person based on their demographic characteristics. FEV1 is a key measurement in pulmonary function testing (spirometry) that quantifies the amount of air a person can forcefully exhale in the first second of a full exhalation.

The predicted FEV1 value is calculated using established equations that take into account factors such as age, height, sex, and sometimes ethnicity. These equations are derived from studies of large populations of healthy individuals. For example, a taller, younger male will generally have a higher predicted FEV1 than a shorter, older female.

When spirometry is performed, the actual measured FEV1 is compared to the predicted FEV1 to determine the percentage predicted. This percentage is crucial for diagnosing and monitoring respiratory conditions like asthma, COPD, and cystic fibrosis. A significantly lower percentage predicted FEV1 suggests impaired lung function. Doctors use the FEV1 predicted value as a reference point to assess the severity of lung disease and track changes over time.