Pulmonary Function tests are widely used in clinical practice in the assessment of a variety of patients. the values obtained in this test are obtained using the standard formula made by Morris et al based on the age and height of Caucasian population.

in this study, a comparison was made of the PFT results of 358 patients using both the Morris Standard formula and those made by Roa et al based on a filipino population, using the statistical program MICROSTAT. results revealed a statistically significant difference in practically all variables, except for the FEV% and the FVC in males, this means therefore that the filipino standard developed by Roa et al should be used since the final patient classification significantly changes.