“…The focus of previous studies on ECG-based authentication has been broadly in two areas (Table 5): (a) conventional machine learning techniques (Bin Safie, Nurfazira, Azavitra, Soraghan, & Petropoulakis, 2014;Choudhary & Manikandan, 2015;Gurkan, Guz, & Yarman, 2013;Guven, Gürkan, & Guz, 2018;Hammad, Luo, & Wang, 2019;Karegar, Fallah, & Rashidi, 2017;Louis, Komeili, & Hatzinakos, 2016;Pal & Singh, 2018;Safie, Soraghan, & Petropoulakis, 2011;Salloum & Kuo, 2017) or (b) deep learning-based approaches (Hammad, Liu, & Wang, 2018;Hammad, Zhang, & Wang, 2019;Luz, Moreira, Oliveira, Schwartz, & Menotti, 2018;Labati, Munoz, Piuri, Sassi, & Scotti, 2018).…”