Table 3.
Geolocation concepts and derived digital biomarkers
| Geolocation Concepts and Derived Digital Biomarkers |
Data | Reference(s) | |
|---|---|---|---|
| Concept | Digital Biomarker | ||
| Mobility | Distance traveled | 8 (44) | 56 , 58–60 , 62 , 63 , 65 , 67 |
| Number of changes in GSM cell ids | 4 (22) | 53–55 , 58 | |
| Standard deviation of distances | 3 (17) | 60 , 63 , 65 | |
| Maximum displacement from primary location | 2 (11) | 63 , 65 | |
| Total number of cells visited | 1 (6) | 53 | |
| Mobility ratea | 1 (6) | 53 | |
| Maximum distance between locations | 1 (6) | 63 | |
| Maximum distance from home | 1 (6) | 60 | |
| Locations | Locations visited | 8 (44) | 51 , 52 , 56 , 57 , 59–61 , 67 |
| Time spent at prespecified locations | 7 (39) | 59 , 60 , 62–65 , 68 | |
| Time spent outdoors | 2 (11) | 66 , 67 | |
| Regularity | Location entropy | 4 (22) | 59 , 60 , 63 , 65 |
| Locational routine indexb | 1 (6) | 60 , 63 | |
| Diurnal movements indexesc | 1 (6) | 59 | |
| Activities | Out-of-home activitiesd | 1 (6) | 57 |
Values are n (%).
a
Calculated as number of changes in cell ids/total number of cells visited.
b
Locational routine index over 7 days to quantify the degree of repetition in terms of places visited with respect to the time of day over a specific period of time.
c
A measure of daily regularity quantified using the Lomb–Scargle periodogram to determine the power in frequencies with wavelengths around 24 hours.
d
Inferring different types of daily activities (eg, employment, shopping, sports, social activities, recreational activities, other).