title: Feasibility and variability of measuring the Lung Clearance Index in a multi-center setting.
abstract: The Lung Clearance Index (LCI) is superior to spirometry in detecting early lung disease in cystic fibrosis (CF) and correlates with structural lung changes seen on CT scans. The LCI has the potential to become a novel outcome parameter for clinical and research purposes. However longitudinal studies are required to further prove its prognostic value. Multi-center design is likely to facilitate realization of such studies. Therefore the aim of the present study was to assess multi-center feasibility and inter-center variability of LCI measurements in healthy children and adolescents. Comparative measurements were performed in unselected patients with CF to confirm previous single-center results. LCI measurements were performed in eight centers using the EasyOne Pro, MBW Module (ndd Medical Technologies, Zurich, Switzerland). The overall success rate for LCI measurements was 75.5%, leaving 102/151 measurements in healthy volunteers and 139/183 measurements in patients with CF for final analysis. Age ranged between 4 and 24 years. Mean LCI (range of means among centers) was 6.3 (6.0-6.5) in healthy volunteers and thus normal. Inter-center variability of center means was 2.9%, ANOVA including Schffé procedure demonstrated no significant inter-center differences (P > 0.05). Mean LCI (range of means among centers) was 8.2 (7.4-8.9) in CF and thus abnormal. Our study demonstrates good multi-center feasibility and low inter-center variability of the LCI in healthy volunteers when measured with the EasyOne Pro MBW module. Our data confirm published LCI data in CF. However, central coordination, quality control, regular training, and supervision during the entire study appear essential for successfully performing multi-center trials.
authors.affiliation: Marien Hospital Wesel, Children's Hospital and Research Institute, Wesel, Germany.
authors.forename: Susanne I
authors.initials: SI
authors.lastname: Fuchs
authors.forename: Helmut
authors.initials: H
authors.lastname: Ellemunter
authors.forename: Johannes
authors.initials: J
authors.lastname: Eder
authors.forename: Uwe
authors.initials: U
authors.lastname: Mellies
authors.forename: Jörg
authors.initials: J
authors.lastname: Grosse-Onnebrink
authors.forename: Burkhard
authors.initials: B
authors.lastname: Tümmler
authors.forename: Doris
authors.initials: D
authors.lastname: Staab
authors.forename: Andrea
authors.initials: A
authors.lastname: Jobst
authors.forename: Matthias
authors.initials: M
authors.lastname: Griese
authors.forename: Jan
authors.initials: J
authors.lastname: Ripper
authors.forename: Ernst
authors.initials: E
authors.lastname: Rietschel
authors.forename: Susanne
authors.initials: S
authors.lastname: Zeidler
authors.forename: Frank
authors.initials: F
authors.lastname: Ahrens
authors.forename: Monika
authors.initials: M
authors.lastname: Gappa
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D009079:Mucociliary Clearance; D015203:Reproducibility of Results; D012129:Respiratory Function Tests / Q000379:methods*; D055815:Young Adult