“…Furthermore, different mathematical models have demonstrated a relationship between HRV amplitude and HR correcting it (Chiu et al, 2003; Meste et al, 2005; Bailón et al, 2011; Sacha, 2014; Billman et al, 2015). HR correction effect on HRV analysis was studied to predict risk mortality (Pradhapan et al, 2014). Non linear indices, such as correlation dimension, sample, and approximate entropy, are computed over linearly detrended and normalized series so this effect is already compensated for (Osaka et al, 1993; Pincus et al, 1993; Porta et al, 2007; Voss et al, 2009; Bolea et al, 2014a).…”