Blood Pressure Estimation Using Photoplethysmography Only: Comparison between Different Machine Learning Approaches

Table 4

Estimated DBP from the regression tree for each individual case under the three BP categories and its difference with reference DBP.

Case	Normotensive			Hypertensive			Hypotensive
	Reference DBP	Estimated DBP	Difference	Reference DBP	Estimated DBP	Difference	Reference DBP	Estimated DBP	Difference
1	49.8	49.3	0.5	—	—	—	45.7	46.8	−1.0
2	43.0	64.3	−21.3	—	—	—	44.0	65.1	−21.1
3	54.5	53.3	1.2	—	—	—	48.4	50.0	−1.6
4	59.0	58.5	0.5	—	—	—	—	—	—
5	67.0	65.6	1.4	79.1	79.1	0.0	—	—	—
6	60.5	57.2	3.3	88.0	74.0	14.0	41.6	46.8	−5.2
7	49.3	48.4	0.9	—	—	—	43.1	45.6	−2.5
8	53.0	53.5	−0.5	—	—	—	—	—	—
9	49.3	48.2	1.1	—	—	—	—	—	—
10	51.9	49.9	2.0	54.7	54.7	0.0	—	—	—
11	69.9	66.3	3.6	93.0	80.3	12.7	49.2	54.3	−5.0
12	63.2	60.2	3.0	—	—	—	46.7	47.7	−1.0
13	64.6	61.5	3.0	—	—	—	56.0	60.2	−4.2
14	—	—	—	—	—	—	57.6	56.7	0.9
15	—	—	—	—	—	—	54.3	54.3	0.1
16	—	—	—	—	—	—	56.2	57.3	−1.1
17	58.3	59.8	−1.6	—	—	—	45.5	52.8	−7.3
18	59.7	62.2	−2.5	—	—	—	—	—	—
19	51.6	64.6	−13.0	77.0	60.9	16.1	—	—	—
20	60.3	62.5	−2.2	76.0	77.4	−1.4	50.0	65.8	−15.8
21	45.4	51.6	−6.2	—	—	—	45.7	50.6	−4.9
22	63.1	58.9	4.2	62.5	61.3	1.2	40.0	62.5	−22.5
23	74.1	69.1	5.0	82.3	71.7	10.6	—	—	—
24	61.5	67.3	−5.8	—	—	—	—	—	—
25	63.9	62.0	1.9	73.2	66.1	7.1	51.7	63.0	−11.3
26	57.4	60.2	−2.8	75.0	60.2	14.8	53.0	67.0	−14.0
27	71.1	68.2	2.8	—	—	—	—	—	—
28	60.7	63.2	−2.5	87.5	72.3	15.2	—	—	—
29	65.8	61.7	4.1	—	—	—	52.3	57.5	−5.2
30	71.1	63.3	7.8	—	—	—	—	—	—
31	70.8	68.5	2.3	87.4	76.0	11.5	57.4	68.3	−10.9
32	66.6	65.5	1.1	88.0	76.8	11.2	—	—	—
Mean	59.8	60.1	−0.3	78.7	70.0	8.6	49.3	56.4	−7.0
SD	8.2	6.3	5.6	10.9	8.4	6.5	5.4	7.4	7.0