title: Diagnostic accuracy of the bronchodilator response in children.
abstract: BACKGROUND
  The bronchodilator response (BDR) reflects the reversibility of airflow obstruction and is recommended as an adjunctive test to diagnose asthma. The validity of the commonly used definition of BDR, a 12% or greater change in FEV1 from baseline, has been questioned in childhood.
  
  
  OBJECTIVE
  We sought to examine the diagnostic accuracy of the BDR test by using 3 large pediatric cohorts.
  
  
  METHODS
  Cases include 1041 children with mild-to-moderate asthma from the Childhood Asthma Management Program. Control subjects (nonasthmatic and nonwheezing) were chosen from Project Viva and Home Allergens, 2 population-based pediatric cohorts. Receiver operating characteristic curves were constructed, and areas under the curve were calculated for different BDR cutoffs.
  
  
  RESULTS
  A total of 1041 cases (59.7% male; mean age, 8.9 ± 2.1 years) and 250 control subjects (46.8% male; mean age, 8.7 ± 1.7 years) were analyzed, with mean BDRs of 10.7% ± 10.2% and 2.7% ± 8.4%, respectively. The BDR test differentiated asthmatic patients from nonasthmatic patients with a moderate accuracy (area under the curve, 73.3%). Despite good specificity, a cutoff of 12% was associated with poor sensitivity (35.6%). A cutoff of less than 8% performed significantly better than a cutoff of 12% (P = .03, 8% vs 12%).
  
  
  CONCLUSIONS
  Our findings highlight the poor sensitivity associated with the commonly used 12% cutoff for BDR. Although our data show that a threshold of less than 8% performs better than 12%, given the variability of this test in children, we conclude that it might be not be appropriate to choose a specific BDR cutoff as a criterion for the diagnosis of asthma.
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass; Massachusetts General Hospital, Department of Pediatrics, Division of Pediatric Pulmonary Medicine, Boston, Mass. Electronic address: reszt@channing.harvard.edu.
authors.forename: Sze Man
authors.initials: SM
authors.lastname: Tse
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Diane R
authors.initials: DR
authors.lastname: Gold
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Joanne E
authors.initials: JE
authors.lastname: Sordillo
authors.affiliation: Harvard School of Public Health, Department of Biostatistics, Boston, Mass.
authors.forename: Elaine B
authors.initials: EB
authors.lastname: Hoffman
authors.affiliation: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care, Boston, Mass.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Gillman
authors.affiliation: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care, Boston, Mass.
authors.forename: Sheryl L
authors.initials: SL
authors.lastname: Rifas-Shiman
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Anne L
authors.initials: AL
authors.lastname: Fuhlbrigge
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Kelan G
authors.initials: KG
authors.lastname: Tantisira
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Weiss
authors.affiliation: Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Mass.
authors.forename: Augusto A
authors.initials: AA
authors.lastname: Litonjua
mesh_terms: D001249:Asthma / Q000175:diagnosis* / Q000503:physiopathology; D001993:Bronchodilator Agents; D019819:Budesonide; D002648:Child; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D017835:Nedocromil; D012680:Sensitivity and Specificity
chemical_list: D001993:Bronchodilator Agents; D017835:Nedocromil; D019819:Budesonide
keywords: AUC; Area under the curve; Asthma; BDR; Bronchodilator response; CAMP; Childhood Asthma Management Program; bronchodilator response; diagnosis