Abstract
Methods: Children aged 2–10 years who were healthy, had persistent isolated cough, or who had previous wheeze were studied. On the same occasion, three Rint measurements were made 15 minutes apart, before and after placebo and salbutamol given in random order. Results from those given placebo first were analysed for within-occasion repeatability. Between-occasion repeatability measurements were made 2–20 weeks apart (median 3 weeks).
Results: For 85 pairs of measurements before and after placebo the limits of agreement were 20% expected resistance and were unaffected by age or health status. The change in resistance following bronchodilator in one of 18 healthy children, 12 of 28 with cough, and 22 of 39 with wheeze exceeded this threshold. For between-occasion measurements the limits of agreement were 32% in 72 healthy subjects, 49% in 57 with cough, and 53% in 95 with previous wheeze.
Conclusion: The measurement of airways resistance by the interrupter technique is clinically meaningful when change following an intervention such as the administration of bronchodilator is greater than its within-occasion repeatability. Between-occasion repeatability is too poor to judge change confidently.
Full Text
The Full Text of this article is available as a PDF (116.0 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bisgaard H., Klug B. Lung function measurement in awake young children. Eur Respir J. 1995 Dec;8(12):2067–2075. doi: 10.1183/09031936.95.08122067. [DOI] [PubMed] [Google Scholar]
- Bridge P. D., Ranganathan S., McKenzie S. A. Measurement of airway resistance using the interrupter technique in preschool children in the ambulatory setting. Eur Respir J. 1999 Apr;13(4):792–796. doi: 10.1034/j.1399-3003.1999.13d16.x. [DOI] [PubMed] [Google Scholar]
- Chinn S. Statistics in respiratory medicine. 2. Repeatability and method comparison. Thorax. 1991 Jun;46(6):454–456. doi: 10.1136/thx.46.6.454. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ducharme F. M., Davis G. M. Measurement of respiratory resistance in the emergency department: feasibility in young children with acute asthma. Chest. 1997 Jun;111(6):1519–1525. doi: 10.1378/chest.111.6.1519. [DOI] [PubMed] [Google Scholar]
- Gustafsson P., Tsanakas J., Gold M., Primhak R., Radford M., Gillies E. Comparison of the efficacy and safety of inhaled fluticasone propionate 200 micrograms/day with inhaled beclomethasone dipropionate 400 micrograms/day in mild and moderate asthma. Arch Dis Child. 1993 Aug;69(2):206–211. doi: 10.1136/adc.69.2.206. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hopkins W. G. Measures of reliability in sports medicine and science. Sports Med. 2000 Jul;30(1):1–15. doi: 10.2165/00007256-200030010-00001. [DOI] [PubMed] [Google Scholar]
- Lombardi E., Sly P. D., Concutelli G., Novembre E., Veneruso G., Frongia G., Bernardini R., Vierucci A. Reference values of interrupter respiratory resistance in healthy preschool white children. Thorax. 2001 Sep;56(9):691–695. doi: 10.1136/thorax.56.9.691. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKenzie S. A., Bridge P. D., Healy M. J. Airway resistance and atopy in preschool children with wheeze and cough. Eur Respir J. 2000 May;15(5):833–838. doi: 10.1034/j.1399-3003.2000.15e04.x. [DOI] [PubMed] [Google Scholar]
- McKenzie S. A., Chan E., Dundas I., Bridge P. D., Pao C. S., Mylonopoulou M., Healy M. J. R. Airway resistance measured by the interrupter technique: normative data for 2-10 year olds of three ethnicities. Arch Dis Child. 2002 Sep;87(3):248–251. doi: 10.1136/adc.87.3.248. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McKenzie S. A., Mylonopoulou M., Bridge P. D. Bronchodilator responsiveness and atopy in 5-10-yr-old coughers. Eur Respir J. 2001 Dec;18(6):977–981. doi: 10.1183/09031936.01.00071901. [DOI] [PubMed] [Google Scholar]
- Merkus P. J., Mijnsbergen J. Y., Hop W. C., de Jongste J. C. Interrupter resistance in preschool children: measurement characteristics and reference values. Am J Respir Crit Care Med. 2001 May;163(6):1350–1355. doi: 10.1164/ajrccm.163.6.2005076. [DOI] [PubMed] [Google Scholar]
- Mitnick Carole, Bayona Jaime, Palacios Eda, Shin Sonya, Furin Jennifer, Alcántara Felix, Sánchez Epifanio, Sarria Madeleny, Becerra Mercedes, Fawzi Mary C. Smith. Community-based therapy for multidrug-resistant tuberculosis in Lima, Peru. N Engl J Med. 2003 Jan 9;348(2):119–128. doi: 10.1056/NEJMoa022928. [DOI] [PubMed] [Google Scholar]
- Pao C. S., Bridge P. D., McKenzie S. A. Not all laboratories are alike. Eur Respir J. 2001 May;17(5):1054–1054. [PubMed] [Google Scholar]
- Pao Caroline S., McKenzie Sheila A. Randomized controlled trial of fluticasone in preschool children with intermittent wheeze. Am J Respir Crit Care Med. 2002 Oct 1;166(7):945–949. doi: 10.1164/rccm.200203-265OC. [DOI] [PubMed] [Google Scholar]
- Quanjer P. H., Stocks J., Polgar G., Wise M., Karlberg J., Borsboom G. Compilation of reference values for lung function measurements in children. Eur Respir J Suppl. 1989 Mar;4:184S–261S. [PubMed] [Google Scholar]
- Strachan D. P. Repeatability of ventilatory function measurements in a population survey of 7 year old children. Thorax. 1989 Jun;44(6):474–479. doi: 10.1136/thx.44.6.474. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Van Noord J. A., Smeets J., Clément J., Van de Woestijne K. P., Demedts M. Assessment of reversibility of airflow obstruction. Am J Respir Crit Care Med. 1994 Aug;150(2):551–554. doi: 10.1164/ajrccm.150.2.8049845. [DOI] [PubMed] [Google Scholar]
- van Altena R., Gimeno F. Respiratory resistance measured by flow-interruption in a normal population. Respiration. 1994;61(5):249–254. doi: 10.1159/000196347. [DOI] [PubMed] [Google Scholar]