Interrupter respiratory resistance in healthy Chinese preschool children.
BACKGROUND
Interrupter respiratory resistance (Rint) is useful in evaluating lung function in children who cannot perform the traditional lung function tests. However, available reference Rint values are confined to whites. Our aims were as follows: (1) to establish reference values in local preschool Chinese children, (2) to examine their relationship with demographic and anthropometric factors, and (3) to determine the 10-min and 6-week repeatability of Rint.


METHODS
Rint was measured in preschool children from randomly chosen local kindergartens, and the repeatability of Rint measurement was assessed in a subgroup of subjects 10 min and 6 weeks after the initial measurement.


RESULTS
Rint measurement was performed in 509 children between 4 and 6 years of age. Age, height, and weight significantly inversely correlated with Rint values. However, on multiple linear regression, height was the only variable that independently correlated with Rint. Repeat measurements obtained 10 min and 6 weeks after the initial reading in 45 children showed good agreement with little variability, and the interclass correlation coefficients for 10-min and 6-week measurements were 0.877 and 0.923, respectively.


CONCLUSIONS
Rint reference centile curves for Chinese preschool children have been determined. Rint in preschool Chinese children has good short- and long-term repeatability.
Li
Albert M
AM
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong. Electronic address: albertmli@cuhk.edu.hk.
Lam
Hugh S
HS
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
So
Hung K
HK
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
Leung
Moon
M
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
Tsen
Tracy
T
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
Au
Chun T
CT
Department of Paediatrics, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, Hong Kong.
Chang
Anne B
AB
Department of Respiratory Medicine, Royal Children's Hospital, Brisbane, QLD, Australia; Child Health Division, Menzies School of Health Research, Darwin, NT, Australia.
D000367:Age Factors; D000403:Airway Resistance / Q000502:physiology*; D000886:Anthropometry; D002648:Child; D002669:Child Welfare; D002675:Child, Preschool; D002681:China; D015331:Cohort Studies; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008403:Mass Screening / Q000379:methods*; D011336:Probability; D012016:Reference Values; D012129:Respiratory Function Tests / Q000379:methods*; D012137:Respiratory System; D012737:Sex Factors; D018709:Statistics, Nonparametric