Table 1.

Summary of the database retrieved.

Authors	Dataset	Subjects	Samples	Signals
Slapničar et al. [21]	MIMIC III	510	—	PPG
Aguirre et al. [18]	MIMIC III	1131	6478	PPG
Leitner et al. [31]	MIMIC III	100	—	PPG
Baek et al. [92]	MIMIC II	942	1912	PPG, ECG
Schlesinger et al. [93]	MIMIC II	329	136459	PPG
Wang et al. [94]	MIMIC II	72	58795	PPG
Yen et al. [87]	UCI_BP	1551	—	PPG
Panwar et al. [86]	UCI_BP	1557	—	PPG
Khalid et al. [58]	Queensland, MIMIC II	—	8133, 9877	PPG
Han et al. [33]	PPG_BP Figshare	—	116	PPG