Spirometric reference values in the occupational medicine practice.

In comparison to the GLI 2012, the ERS 1993 values significantly underestimated obstructive and restrictive alterations. Conversely, the ECSC 1971 significantly underestimated obstructive changes, while overestimated restrictive patterns, compared to GLI. Although the GLI reference values may provide a correct spirometric interpretation, their validation in an Italian worker population is necessary to confirm their possible use in routine occupational health programs.