BACKGROUND: Recently, it has been proved that fractional exhaled @entity842 (FENO) results are in disagreement with other measurements of @entity565 control. The objective of this work is to present and validate new @entity55 ratios. METHODS: This is a retrospective, cross-sectional study in which we evaluated data from medical documentation of 1,529 pediatric and adolescent subjects and a small number (2% of the studied population) of young adults, who presented symptoms suggestive of @entity565 (age range 4-24 y). We are the first to analyze results obtained in this manner (before the introduction of controlled medication): FENO, spirometry, specific resistance of the airways, diagnosis of @entity56 , and allergen sensitization (specific immunoglobulin E results). RESULTS: Cut-off points for the new indicators allowed us to diagnose @entity565 in the study @entity1 : for FVC/FENO ratio, 0.17 L/ppb; for FEV1/FENO ratio, 0.15 L/ppb; for forced expiratory flow during the middle half of the FVC maneuver (FEF25-75%)/FENO ratio, 0.16 L/ppb; for FENO/FVC ratio, 11.00 ppb/L; for FENO/FEV1 ratio, 12.53 ppb/L; and for FENO/FEF25-75% ratio, 11.81 ppb/L. Only the ratios described above were closely correlated with the diagnosis of @entity565 and with one another. They significantly differed between subjects with @entity565 and healthy subjects as well as between females and males. Only FEF25-75%/FENO and FENO/FEF25-75% values were significant predictors of any sensitization in the studied subjects. We found higher sensitivity than specificity and higher positive predictive value than negative predictive value for FVC/FENO, FEV1/FENO, and FEF25-75%/FENO and found a mirror image for reverse parameters. However, the positive predictive values and negative predictive values were not clearly convincing with respect to diagnostic accuracy in the case of the new parameters proposed. CONCLUSIONS: We propose new @entity55 ratios by which it may become possible to diagnose @entity565 in @entity1 and adolescents on the basis of a subject's spirometry and FENO measurements. We believe that our ratios are only supportive of the universally used parameters in the process of diagnosing @entity565 .

Spirometry-Adjusted Fraction of Exhaled @entity842 Allows Asthma Diagnosis in XXXX , Adolescents, and Young Adults.

@entity1 :: ('9606', 'Species') :: ['participants', 'children'] @entity55 :: ('MESH:D011014', 'Disease') :: ['lung function/lung inflammation'] @entity565 :: ('MESH:D001249', 'Disease') :: ['asthma'] @entity56 :: ('MESH:D004342', 'Disease') :: ['allergic diseases'] @entity842 :: ('MESH:D009569', 'Chemical') :: ['nitric oxide']
@entity1 :: (9606,Species) :: ['Children']
