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Cited by 543

The DOI matches its Crossref record; 3 of the 3 references it cites were found in a registry or an index.

Statistics Notes: Measurement error proportional to the mean

Open access
Bland, J Martin, Altman, Douglas G·1996·BMJ

Abstract

We often need to know the error with which measurements are made—for example, so that we can decide whether the change in a clinical observation represents a real change in a patient's condition. We have discussed previously the within-subject standard deviation as a practical index of measurement error.1 We said that this approach should be used when the measurement error was not related to the magnitude of the measurement and recommended that we plot the subject standard deviation against the subject mean to check this. Table 1 shows some duplicate salivary cotinine measurements taken from a larger study. Figure 1 shows absolute subject difference against subject mean, which is equivalent to a standard deviation versus mean plot when we have only two measurements per subject.1 If we are to use the within-subject standard deviation as an index of measurement error we need the subject standard deviation to be …

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Crossref · 10.1136/bmj.313.7049.106

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Metadata

Authors
Bland, J. M., & Altman, D. G.
Venue
BMJ
Publisher
BMJ
Published
1996-07-13
Volume
313
Issue
7049
Pages
106
ISSN
  • 0007-1447 (ISSN-L)
  • 0959-8138
  • 1468-5833
OpenAlex
W141585252
Cited by
543
References
3
FWCI
8.42
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: Statistics Notes: Measurement error proportional to the mean. https://app.cochat.ai/papers/10.1136/bmj.313.7049.106
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Bland, J. M., & Altman, D. G. (1996). Statistics Notes: Measurement error proportional to the mean. BMJ. https://doi.org/10.1136/bmj.313.7049.106

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.