Journal ArticleDOI
Measuring agreement in method comparison studies
J M Bland,Douglas G. Altman +1 more
TLDR
The 95% limits of agreement, estimated by mean difference 1.96 standard deviation of the differences, provide an interval within which 95% of differences between measurements by the two methods are expected to lie.Abstract:
Agreement between two methods of clinical measurement can be quantified using the differences between observations made using the two methods on the same subjects. The 95% limits of agreement, estimated by mean difference +/- 1.96 standard deviation of the differences, provide an interval within which 95% of differences between measurements by the two methods are expected to lie. We describe how graphical methods can be used to investigate the assumptions of the method and we also give confidence intervals. We extend the basic approach to data where there is a relationship between difference and magnitude, both with a simple logarithmic transformation approach and a new, more general, regression approach. We discuss the importance of the repeatability of each method separately and compare an estimate of this to the limits of agreement. We extend the limits of agreement approach to data with repeated measurements, proposing new estimates for equal numbers of replicates by each method on each subject, for unequal numbers of replicates, and for replicated data collected in pairs, where the underlying value of the quantity being measured is changing. Finally, we describe a nonparametric approach to comparing methods.read more
Citations
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Journal ArticleDOI
An Overview of Heart Rate Variability Metrics and Norms.
Fred Shaffer,Jay P. Ginsberg +1 more
TL;DR: Current perspectives on the mechanisms that generate 24 h, short-term (<5 min), and ultra-short-term HRV are reviewed, and the importance of HRV, and its implications for health and performance are reviewed.
Journal ArticleDOI
Understanding Bland Altman analysis
TL;DR: The aim of this article is to provide guidance on the use and interpretation of Bland Altman analysis in method comparison studies.
Journal ArticleDOI
Reliability of the visual analog scale for measurement of acute pain.
TL;DR: Reliability of the VAS for acute pain measurement as assessed by the ICC appears to be high, and data suggest that the Vas is sufficiently reliable to be used to assess acute pain.
Journal ArticleDOI
Guidelines for Reporting Reliability and Agreement Studies (GRRAS) were proposed.
Jan Kottner,Laurent Audigé,Stig Brorson,Allan Donner,Byron J. Gajewski,Asbjørn Hróbjartsson,Chris Roberts,Mohamed Shoukri,David L. Streiner +8 more
TL;DR: In this paper, the authors developed guidelines for reporting reliability and agreement studies in interrater and intra-arater reliability and agreements, and proposed 15 issues that should be addressed when reporting such studies.
Journal ArticleDOI
Agreement Between Methods of Measurement with Multiple Observations Per Individual
J M Bland,Douglas G. Altman +1 more
TL;DR: Methods for analysing clustered observations, both when the underlying quantity is assumed to be changing and when it is not, are described.
References
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Journal ArticleDOI
Statistical methods for assessing agreement between two methods of clinical measurement.
TL;DR: An alternative approach, based on graphical techniques and simple calculations, is described, together with the relation between this analysis and the assessment of repeatability.
Journal ArticleDOI
Measurement in Medicine: The Analysis of Method Comparison Studies
Douglas G. Altman,J M Bland +1 more
TL;DR: This paper shall describe what is usually done, show why this is inappropriate, suggest a better approach, and ask why such studies are done so badly.
Journal ArticleDOI
Comparing methods of measurement: why plotting difference against standard method is misleading
J M Bland,Douglas G. Altman +1 more
TL;DR: A plot of the difference against the average of the standard and new measurements is unlikely to mislead in this way and is shown theoretically and by a practical example.
Journal ArticleDOI
Clinical assessment of gestational age in the newborn infant
TL;DR: A scoring system for gestational age, based on 10 neurologic and 11 “external” criteria, has been applied to 167 newborn infants and gives consistent results within the first 5 days and is equally reliable in the first 24 hours of life.
Journal ArticleDOI
A note on the use of the intraclass correlation coefficient in the evaluation of agreement between two methods of measurement.
J M Bland,Douglas G. Altman +1 more
TL;DR: It is shown that neither technique is appropriate for assessing the interchangeability of measurement methods, and an alternative approach based on estimation of the mean and standard deviation of differences between measurements by the two methods is described.