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

Table 3

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

Case	Normotensive			Hypertensive			Normotensive
	Reference SBP	Estimated SBP	Difference	Reference SBP	Estimated SBP	Difference	Reference SBP	Estimated SBP	Difference
1	98.0	97.6	0.4	—	—	—	85.7	92.4	−6.7
2	120.2	108.2	12.1	—	—	—	85.1	115.7	−30.6
3	99.5	100.7	−1.1	—	—	—	80.2	99.1	−18.9
4	107.6	108.2	−0.6	—	—	—	—	—	—
5	121.8	120.4	1.4	188.7	185.6	3.2	—	—	—
6	108.5	104.5	4.0	188.9	155.4	33.5	84.2	93.2	−9.0
7	97.3	101.6	−4.3	—	—	—	87.6	90.7	−3.1
8	104.4	105.9	−1.5	—	—	—	—	—	—
9	105.7	103.2	2.4	—	—	—	—	—	—
10	117.7	107.0	10.7	104.0	104.0	0.0	—	—	—
11	111.1	110.2	1.0	131.9	130.6	1.3	87.7	100.5	−12.8
12	103.0	103.3	−0.3	—	—	—	78.9	85.7	−6.8
13	101.7	102.2	−0.6	—	—	—	84.0	86.5	−2.5
14	—	—	—	—	—	—	84.8	87.0	−2.1
15	—	—	—	—	—	—	84.6	88.2	−3.6
16	—	—	—	—	—	—	85.0	86.6	−1.6
17	93.6	103.9	−10.3	—	—	—	82.5	124.4	−41.9
18	113.7	117.1	−3.4	—	—	—	—	—	—
19	106.3	115.9	−9.6	145.0	117.3	27.8	—	—	—
20	116.0	115.8	0.2	144.0	105.9	38.1	87.0	116.0	−29.0
21	99.9	106.3	−6.4	—	—	—	85.0	97.8	−12.8
22	116.0	111.6	4.4	150.4	124.9	25.5	87.0	117.4	−30.4
23	123.2	134.1	−11.0	155.7	131.8	23.9	—	—	—
24	95.0	97.7	−2.7	—	—	—	—	—	—
25	119.5	120.2	−0.7	147.8	127.7	20.1	83.7	125.9	−42.1
26	117.0	114.9	2.0	162.0	124.3	37.7	87.0	109.5	−22.5
27	124.0	118.6	5.4	—	—	—	—	—	—
28	106.3	115.2	−8.9	135.5	121.2	14.3	—	—	—
29	105.7	102.9	2.8	—	—	—	83.8	91.8	−8.0
30	108.0	118.3	−10.3	—	—	—	—	—	—
31	114.9	118.5	−3.6	147.0	125.0	22.0	85.2	105.7	−20.5
32	118.7	122.7	−4.0	171.6	146.0	25.6	—	—	—
Mean	109.4	110.5	−1.1	151.7	130.7	21.0	84.6	100.7	−16.0
SD	8.9	8.6	5.7	22.9	21.5	12.9	2.3	13.5	13.3