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Cited by 1,278Asthma and respiratory diseasesChronic Obstructive Pulmonary Disease (COPD) ResearchStatistical Methods in Epidemiology

The DOI matches its Crossref record; 4 of the 4 references it cites were found in a registry or an index.

Statistics Notes: Detecting skewness from summary information: Table 1

Open access
Altman, Douglas G, Bland, J Martin·1996·BMJ
DOI 10.1136/bmj.313.7066.1200PMC PMC2352469
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Abstract

The measurement of airway resistance by the interrupter technique (Rint) needs standardization. Should measurements be made be during the expiratory or inspiratory phase of tidal breathing? In reported studies, the measurement of Rint has been calculated as the median or mean of a small number of values, is there an important difference? Subjects were 2.5–5.0 yrs (median 4.0 yrs) who had previous respiratory symptoms. The Rint in expiration (RintE) and inspiration (RintI) pre and postsalbutamol, the coefficient of variation (CV) of values contributing to measurements, and bronchodilator responsiveness (BDR) in both phases were compared. Measurements using median and mean were compared. RintE was higher than RintI by 4% (p<0.01). The CV of values making up RintE and RintI, and BDR measured in expiration and inspiration were similar. The median difference between means and medians of values making up measurements was 0.6% (range −6–11%). RintE has been shown to be consistently greater then RintI but the difference in this study is small. It is suggested that one or the other is chosen as the standard. In the present data the mean of a set of values contributing to a measurement was not significantly different from the median. However, the use of the median has been recommended since it is less affected by possible outlying values such as might be included by fully automated equipment.

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Metadata

Authors
Altman, D. G., & Bland, J. M.
Affiliations
University of Oxford (GB)
ORCID
Altman, Douglas G
Venue
BMJ
Publisher
BMJ
Published
1996-11-09
Volume
313
Issue
7066
Pages
1200.1
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
DOI
10.1136/bmj.313.7066.1200
PMC
PMC2352469
OpenAlex
W1591259115
Cited by
1,278
References
4
Citations by year
2026: 10 · 2025: 18 · 2024: 26 · 2023: 24 · 2022: 31 · 2021: 33 · 2020: 43 · 2019: 48 · 2018: 54 · 2017: 65 · 2016: 70 · 2015: 72 · 2014: 79 · 2013: 70 · 2012: 87
FWCI
5.62
Type
journal article
Language
en
Open access
Licence
www.bmj.com/company/legal-information/terms-conditions/legal-information/tdm-licencepolicy (tdm)
Locations
  • BMJ (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Topics
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Asthma and respiratory diseases
  • Health Sciences › Medicine › Pulmonary and Respiratory Medicine › Chronic Obstructive Pulmonary Disease (COPD) Research
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
Keywords
airway resistance, interrupter technique, coefficient of variation, bronchodilator responsiveness, salbutamol, pediatric respiratory symptoms, measurement standardization, skewness
MeSH terms
Analysis of Variance

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