On the Probability of Correct Diagnosis by Pulmonary Function Tests

For many years, chest physicians have cherished the hope that respiratory physiologists wiU devise an effective and simple test to distinguish normal from abnormal subjects. The limitations of well- established tests have gained increasing recogni- tion, and this has led to a rapid multiplication in the number of test procedures. Patients are commonly subjected to a battery of 10 or more tests, but all too commonly a clear separation of normal from abnormal is still not obtained.