Figure 9.

Agreement of spectral components of pulse rate variability (PRV) and heart rate variability (HRV). The amplitudes of spectral components were calculated for sequential 5-min segments over the entire length of data in a representative subject. Left panels: trendgram (panels A and B), scatter plot (panel C) and the Bland and Altman plot (panel D) for the amplitudes of low-frequency components of pulse interval variability (LF_PRV) and R-R interval (LF_HRV). Right panels: trendgram, scatter plot and the Bland and Altman plot of the amplitudes of high-frequency components of pulse interval variability (HF_PRV) and R-R interval (HF_HRV). ICC = intraclass correlation coefficient. Broken lines in the Bland and Altman plots represent the upper and lower limits of agreement (+2 SD and -2 SD, respectively). SD = standard deviation.