Spirometry Test Grading Matrix



This matrix has been developed to give you the confidence to apply your own quality grading & comments and to resist the temptation to rely on your spirometer’s automated quality grading.

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Spirometry Test Grading Matrix by Spirometry Training Company (Aust) Pty Ltd is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

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Operators are required to apply a quality grade to a spirometry report and not rely on the spirometer automation, but this can be confusing and time consuming!  The spirometry test grading matrix has been developed by Spirometry Training Company to minimise confusion in applying a spirometry test quality grade as described in the ATS/ERS standards#.

The measured differences are calculated between the two largest FVC values and the two largest FEV1 values.  A separate quality grade is to be applied for FEV1 and FVC in both pre-bronchodilator and post-bronchodilator results.

The traffic light system offers an easy guide for the interpreting physician to determine the clinical reliability of spirometry results.

#Graham BL, Steenbruggen I, Miller MR, et al. Standardization of Spirometry 2019 Update. An Official American Thoracic Society and European Respiratory Society Technical Statement. Am J Respir Crit Care Med. 2019;200(8):e70–e88. https://doi.org/10.1164/rccm.201908-1590ST