The Pulmonary Function Testing Laboratory has implemented an important update to its reporting system with the transition to
z-score–based interpretation of pulmonary function tests. Under the leadership of
Michael Lazar, M.D., Director of the PFT Lab, this change reflects the growing use of z-scores in pulmonary medicine and provides a more precise way to interpret lung function data.
Traditional PFT interpretation relied largely on percent-predicted values. While familiar, these thresholds can oversimplify physiologic variation across age and body size. Z-scores instead compare a patient’s result to a population distribution and express how far the value deviates from the expected mean. This approach allows clinicians to better understand whether a measurement truly falls outside the normal range.
“Many of our pulmonologists have used z-scores in prior training or at other institutions, but for some who have interpreted PFTs with percent predicted for many years, there is naturally a short adjustment period as everyone gets used to the new format.”
— Michael Lazar, M.D.
Many pulmonologists in the group are already familiar with this framework from prior training or previous institutions where z-scores have been used for years. For others who have interpreted PFTs using percent predicted for most of their careers, the transition has required a brief adjustment period. As expected with any change in reporting standards, there have been some growing pains, but most clinicians are quickly becoming comfortable with the new format as they gain experience reviewing studies.
Dr. Lazar notes that the transition represents an exciting step forward in improving the accuracy and consistency of PFT interpretation across the system.
Along with the transition to z-scores, the PFT software has also been updated to improve readability and workflow for interpreting physicians. Interpretation statements are now spaced to clearly separate
spirometry, lung volumes, and DLCO into distinct paragraphs. This allows clinicians to review each section individually and make adjustments as needed before finalizing the interpretation.
A new interpretation template,
“HENRY FORD INTERPRETATION 2026-01-09,” is now available within the SentrySuite system. Physicians can insert this template by selecting the graduation-cap icon within the physician box. In most cases, PFT technicians will continue to insert the interpretation prior to physician review, though interpreters can add it themselves when needed.
The previous interpretation set will remain on the server for several months during the transition period. Physicians are encouraged to report any issues or suggested improvements as the lab continues refining this updated system.
