Repeatability of lung clearance index in infants with cystic fibrosis and recurrent wheeze.
Pediatr Pulmonol
; 57(7): 1608-1617, 2022 07.
Article
en En
| MEDLINE
| ID: mdl-35419996
ABSTRACT
OBJECTIVES:
To describe the short- and medium-term repeatability of lung clearance index at 2.5% (LCI2.5 ) in infants and calculate the number of patients needed to enroll in a study (N) using LCI2.5 as a primary outcome.METHODS:
An 8-month follow-up observational study was employed for assessing short-term [coefficient of repeatability (CR) and intraclass correlation (ICC)] and medium-term repeatability (Bland-Altman method) of LCI2.5 in infants with cystic fibrosis (CF) or recurrent wheeze (RW) measured by the nitrogen multiple-breath washout test (N2 -MBW). Using these variability data, the N to reach 90% test power at the level of statistical significance (0.05) was calculated.RESULTS:
Forty infants with CF and 21 with RW were enrolled. Initial N2 -MBW testing was successful in 33 and 17 patients, respectively. Follow-up data were available for 23 and 11 infants, respectively. Short-term repeatability of LCI2.5 was high (CR = 1.10 and 1.04 in CF and RW patients, respectively; ICC = 0.88 and 0.83 in CF and RW patients, respectively). The between-subject standard deviation was <13% of the actual LCI2.5 value. In clinically stable patients, LCI2.5 did not significantly change during the 8-month follow-up. Mean LCI2.5 change was -0.08 (1% of baseline) in CF and -0.05 (0.6%) in RW, with 95% limits of agreement being (-1.70; 1.53) in CF and (-1.51; 1.40) in RW patients. N = 23 infants if both intragroup differences of LCI2.5 and minimal difference to be detected would be 2.0.CONCLUSION:
N2 -MBW may be a reproducible tool with reasonable test power to detect differences in infant studies.Palabras clave
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Fibrosis Quística
Tipo de estudio:
Diagnostic_studies
/
Observational_studies
/
Prognostic_studies
Límite:
Humans
/
Infant
Idioma:
En
Revista:
Pediatr Pulmonol
Asunto de la revista:
PEDIATRIA
Año:
2022
Tipo del documento:
Article
País de afiliación:
República Checa