From the paper (abbreviations expanded): Post-Exertional Malaise (PEM) domain score of Symptom Severity Scale instrument—ME/CFS vs. Controls. The shaded area represents the 95% confidence interval. Each dot represents the PEM score for a single subject; Blue dots are low scores, red dots are high scores; Black lines represent the spline curves for group averages; Grey shaded areas are the 95% confidence intervals.
<p>Geoffrey E. Moore, Betsy A. Keller, Jared Stevens, Xiangling Mao, Staci R. Stevens, John K. Chia,
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Susan M. Levine, Carl J. Franconi, and <a href="https://en.wikipedia.org/wiki/Maureen_Hanson" class="extiw" title="w:Maureen Hanson">Maureen R. Hanson</a>
CC BY 4.0
<p>"Recovery from Exercise in Persons with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)"
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URL: <a rel="nofollow" class="external free" href="https://www.mdpi.com/1648-9144/59/3/571">https://www.mdpi.com/1648-9144/59/3/571</a> <a href="https://en.wikipedia.org/wiki/Digital_object_identifier" class="extiw" title="w:Digital object identifier">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.3390%2Fmedicina59030571">10.3390/medicina59030571</a>