Professional societies such as the [[American Thoracic Society/]] and the [[European Respiratory Society]] have published guidelines regarding the conduct and interpretation of pulmonary function testing to ensure standardization and uniformity in performance of tests. The interpretation of tests depends on comparing the patients values to published normals from previous studies. Deviation from guidelines can result in false-positive or false negative test results. Mohanka MR et al. recently demonstrated that only a small minority of pulmonary function laboratories followed published guidelines for spirometry, lung volumes and diffusing capacity in 2012.<ref>{{cite journal|last1=Mohanka|first1=Manish R.|last2=McCarthy|first2=Kevin|last3=Xu|first3=Meng|last4=Stoller|first4=James K.|title=A Survey of Practices of Pulmonary Function Interpretation in Laboratories in Northeast Ohio|journal=Chest|date=April 2012|volume=141|issue=4|pages=1040–1046|doi=10.1378/chest.11-1141|pmid=21940775}}</ref>
