Table 2.
Summarized information per measurement technique
| Total | Accelerometer | Bio-impedance | ECG | PPG | SCG | Thermometer | Other techniquesc | |
|---|---|---|---|---|---|---|---|---|
| Single measurement techniques | N = 65 | N = 53 | N = 8 | N = 2 | N = 1 | N = 1 | N = 0 | N = 0 |
| Type of device, n (%)a | ||||||||
| Wrist-worn device | 35 (53.8) | 33 (62.3) | - | - | 1 (100) | 1 (100) | - | - |
| Hip-worn device | 17 (26.2) | 12 (22.6) | - | - | - | - | - | - |
| Vest | 9 (13.8) | 1 (1.8) | 1 (12.5) | 1 (50.0) | - | - | - | - |
| Patch(es) | 3 (4.6) | 1 (1.8) | 7 (87.5) | 1 (50.0) | - | - | - | - |
| Multi-sensor device | - | - | - | - | - | - | - | - |
| Other typesb | 6 (9.2) | 5 (9.4) | - | - | - | - | - | - |
| Study type, n (%) | ||||||||
| Randomized controlled trials | 5 (7.7) | 4 (7.5) | 1 (12.5) | - | - | - | - | - |
| Observational studies | 57 (87.7) | 48 (90.5) | 6 (75.0) | 2 (100) | 1 (100) | - | - | - |
| Proof-of-concept | 1 (1.5) | - | - | - | - | 1 (100) | - | - |
| Pilot trial | 2 (3.1) | 1 (1.8) | 1 (12.5) | - | - | - | - | - |
| Geographical region, n (%) | ||||||||
| Asia | 9 (13.8) | 5 (9.4) | 1 (12.5) | 2 (100) | - | 1 (100) | - | - |
| Europe | 26 (40.0) | 24 (45.3) | 2 (25.0) | - | - | - | - | - |
| North America | 27(41.5) | 23 (43.4) | 4 (50.0) | - | - | - | - | - |
| Latin America | 1 (1.5) | 1 (1.8) | - | - | - | - | - | - |
| Middle Eastern | 2 (3.1) | - | 1 (12.5) | - | 1 (100) | - | - | - |
| Complex measurement techniques | N = 34 | N = 25 | N = 7 | N = 26 | N = 13 | N = 13 | N = 5 | N = 4 |
|---|---|---|---|---|---|---|---|---|
| Type of device, n (%)a | ||||||||
| Wrist-worn device | 8 (23.5) | 8 (32.0) | - | 1 (3.8) | 7 (53.8) | - | - | - |
| Hip-worn device | 3 (8.8) | 3 (12.0) | 2 (28.6) | 3 (11.5) | 2 (15.4) | - | 1 (20.0) | 1 (25.0) |
| Vest | 14 (41.2) | 10 (40.0) | 3 (42.9) | 14 (53.8) | 2 (15.4) | 10 (76.9) | 1 (20.0) | - |
| Patch(es) | 5 (14.8) | 1 (4.0) | 1 (14.3) | 5 (19.2) | 1 (7.7) | 2 (15.4) | 1 (20.0) | 1 (25.0) |
| Multi-sensor device | 3 (8.8) | 2 (8.0) | 1 (14.3) | 2 (7.7) | - | 1 (7.7) | 1 (20.0) | 1 (25.0) |
| Other typesb | 2 (5.9) | 2 (8.0) | - | 1 (3.8) | 1 (7.7) | - | 2 (40.0) | 2 (50.0) |
| Study type, n (%) | ||||||||
| Randomized controlled trials | 3 (8.8) | 3 (12.0) | - | 1 (3.8) | 2 (15.4) | 1 (7.7) | - | - |
| Observational studies | 24 (70.6) | 18 (72.0) | 4 (57.1) | 19 (73.1) | 7 (53.8) | 2 (15.4) | 3 (60.0) | 2 (50.0) |
| Proof-of-concept | 7 (20.6) | 4 (10.0) | 3 (42.9) | 6 (23.1) | 4 (30.8) | 10 (76.9) | 2 (40.0) | 2 (50.0) |
| Pilot trial | - | - | - | - | - | - | - | - |
| Geographical region, n (%) | ||||||||
| Asia | 4 (11.8) | 2 (8.0) | - | 3 (11.5) | 3 (23.1) | - | 1 (20.0) | 2 (50.0) |
| Europe | 14 (41.2) | 12 (48.0) | 1 (14.3) | 12 (46.2) | 4 (30.8) | 8 (61.5) | 3 (60.0) | 1 (25.0) |
| North America | 16 (47.1) | 11 (44.0) | 6 (85.7) | 11 (42.3) | 6 (46.2) | 5 (38.5) | 1 (20.0) | 1 (25.0) |
| Latin America | - | - | - | - | - | - | - | - |
| Middle Eastern | - | - | - | - | - | - | - | - |
PPG Photoplethysmography, ECG Electrocardiography, SCG Seismocardiography.
aType device: In some more than one wearable is used, and therefore this percentage does in some techniques not add up to 100%.
bOther types include: ankle-worn devices (n = 2), a bracelet worn on the upper arm (n = 1), body-worn devices (n = 3), and waist-worn devices (n = 3).
cOther techniques include: barometry (n = 1), humidity sensor (n = 1), microphone (n = 2).