This site was developed to help explain the spirometry quality review (QC) currently used to grade spirometry tests. To assist in assessments, computer determined grades are first calculated - click Here to see the definitions for the computer determined grades. However, these computer determined grades are used only as an initial guide and a QC reviewer must assign final grades to the FVC and FEV1 for each test.
One key determinant of an acceptable curve is the end of test, perhaps one of the most controversial issue in determining if a curve is acceptable; so, a brief description of End of Test Issues is available. You may also want to view the Frequently Asked Questions link. A General Approach description is available and it is the key to understanding the basis of test grading -- comments are welcomed.
This site also has a QC Project whose research objective is to obtain a consensus on what represents a good test and to simulate discussion. You may view the information but you will need to register to participate.
Many examples of discordant tests are shown in the QC Project and include poor end of test, less than perfect test, and non-repeatable test.