Abstract
Most of the variance in diurnal cortisol is attributable to intraindividual variability (IIV), defined as relatively short-term, reversible changes. Multiple methods for measuring IIV have been proposed, and some have already been applied to cortisol IIV. In the present review, measurement methods are described and applied to simulated cortisol data with known underlying differences in IIV and to real cortisol data from first-year law students. More slope variance and more residual or net variance were well captured by their individual standard deviations. Explorations of reliability suggested that 10 slopes and 50 residuals result in reliable and stable estimates of the individual standard deviations. A data-analytic plan for cortisol IIV is provided.
Document Type
Review
Publication Date
4-2017
Digital Object Identifier (DOI)
https://doi.org/10.1016/j.psyneuen.2017.01.026
Funding Information
This work was made possible by funding from the National Institutes of Health (K02-AG033629, R01-MH61531).
Related Content
Refer to Web version on PubMed Central for supplementary material.
Repository Citation
Segerstrom, Suzanne C.; Sephton, Sandra E.; and Westgate, Philip M., "Intraindividual Variability in Cortisol: Approaches, Illustrations, and Recommendations" (2017). Psychology Faculty Publications. 180.
https://uknowledge.uky.edu/psychology_facpub/180
Supplemental Online Material A.
NIHMS847511-supplement-2.xlsx (16 kB)
Supplemental Online Material B.
Notes/Citation Information
Published in Psychoneuroendocrinology, v. 78, p. 114-124.
© 2017 Elsevier Ltd. All rights reserved.
This manuscript version is made available under the CC‐BY‐NC‐ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/.
The document available for download is the author's post-peer-review final draft of the article.