Fig. 2From: Reduced heart rate variability predicts fatigue severity in individuals with chronic fatigue syndrome/myalgic encephalomyelitisComparison of the HRV frequency-domain measures in the study participants. Values are shown as mean ± SEM of a absolute power of the low frequency band (LF), b absolute power of the high frequency band (HF), c normalized HF value (HFnu) and d ratio of LF-to-HF power (LF/HF). Significance level is indicated above the horizontal line in each chartBack to article page