RT Journal Article
SR Electronic
T1 Variability and reproducibility in the measurement of tracheobronchial clearance in healthy subjects and patients with different obstructive lung diseases
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP 613
OP 620
DO 10.1183/09031936.93.01070613
VO 1
IS 7
A1 M Del Donno
A1 D Pavia
A1 JE Agnew
A1 MT Lopez-Vidriero
A1 SW Clarke
YR 1988
UL http://erj.ersjournals.com/content/1/7/613.abstract
AB The purpose of this study was to establish the inter- and intra-subject/patient variability of tracheobronchial clearance, measured for 6 h, using a radioaerosol technique. Inter-subject variability was evaluated in five groups: 33 healthy non-smokers (NS); 19 asymptomatic smokers (S); 40 asthmatics (A); 27 chronic bronchitics (CB) and 12 bronchiectatics (B). Intra-subject variability was evaluated in 16 A and 27 CB who were studied twice. The inter-subject/patient coefficient of variation (CoV) of tracheobronchial clearance was 13% for NS and 28-39% for the remaining four groups. The intra-patient CoV was about half of the inter-patient CoV. Inter-subject CoV (for A and CB) appeared to be independent of initial tracheobronchial deposition of radioaerosol and frequency of cough. We were also able to estimate the approximate number of patients required for a crossover study in order to avoid statistical, type II errors when investigating the effect of a drug or of a therapeutic intervention on tracheobronchial clearance.