Dr Madan and colleagues also recommended that before adopting the FEV3/FVC ratio for common use, it should be validated using other radiographic and clinical assessments. But what if this is the more sensitive measurement? Without concomitant emphysema, a CT scan would appear normal unless air trapping was sufficient to cause a mosaic pattern. Clinically, subjects with milder forms of diseases such as diabetes or hypertension can remain asymptomatic for years. Hansen et al4 clearly showed the association of smoking to a reduction in this ratio. Our study supported this relationship. In 1984, Morris et al5 and the Intermountain Thoracic Society advocated using this ratio and its lower limit of normal to identify mild/midflow obstruction. Short of pathologic correlation with lung biopsies, large patient databases may be the most sensitive way to identify small physiologic differences between groups. We are not advocating that the FEV3/FVC replace the FEV1/FVC ratio, but rather feel it may have an important complimentary role in identifying milder disease. In response to the opinion that the term lung injury should be restricted to the diagnosis of ARDS, we used these words in the same context as our pathology colleagues who routinely use this phrase to describe damage to the lungs no matter what the cause, including ARDS.