Spirometry in clinical practice.

The practicality of office spirometry has been established. Two basic parameters can be quickly and accurately measured in the physician's office or clinic: forced vital capacity (FVC) as a test of volume, indicative of restrictive lung disease, and forced expiratory volume in one second (FEV1) as a test of flow, indicative of obstructive lung disease. The ratio of FEV1 to FVC (FEV1/FVC%) is a valuable screening tool. Test results are compared with normal values, and abnormalities must be interpreted in the context of the individual patient's history and condition. Office spirometry provides a simple, noninvasive, inexpensive tool for assessing and managing respiratory disease.