Performance
Performance of activity recognition versus human observation
VitaMove is medically validated. Perfomance of the VitaMove system was compared to human observance / classification using a protocol of different activities. The following targets for mean of sensitivity and specificity are used for the automatic analysis function in, comparison to manual human observation:
- > 90 % for Postures like Lying Supine, Prone, Lying left/Right, Standing & Sitting
- > 80 % for Movements like Moving, Walking, Running, Bicycling.
The following table is a contingency table of all the Body Activities collected over N = 7 subjects. The numbers represent the amount of seconds that the activity was detected.
| Man/Auto | Supine | Prone | Leftside | Rightside | Stand | Sit | Move | Walk | Run | Cycle |
| Supine | 1145 | 0 | 0 | 0 | 0 | 25 | 0 | 0 | 0 | 0 |
| Prone | 0 | 857 | 14 | 12 | 0 | 0 | 0 | 0 | 0 | 0 |
| Leftside | 15 | 18 | 606 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Rightside | 0 | 66 | 0 | 777 | 0 | 0 | 0 | 0 | 0 | 0 |
| Stand | 0 | 0 | 0 | 0 | 674 | 0 | 16 | 0 | 0 | 0 |
| Sit | 46 | 0 | 0 | 0 | 0 | 512 | 0 | 0 | 0 | 15 |
| Move | 0 | 2 | 0 | 0 | 4 | 0 | 232 | 56 | 1 | 90 |
| Walk | 0 | 0 | 0 | 0 | 1 | 0 | 17 | 805 | 85 | 36 |
| Run | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 19 | 643 | 0 |
| Cycle | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 195 |
Sensitivity and specificity
Hereby the actual auto classification results in term of sensitivity and specificity. For all main activities and postures except bicycling, sensitivity and specificity targets are met. Bicycling was ‘real-life’ so contaminated with free-wheeling and such; therefore detection includes ‘Sit’ and ‘Move’ lowering the sensitivity.
| Sensitivity | Accuracy | ||
| Supine | 95 | 100 | 99 |
| Prone | 91 | 100 | 98 |
| Leftside | 98 | 99 | 99 |
| Rightside | 98 | 99 | 99 |
| Standing | 99 | 100 | 100 |
| Sitting | 95 | 99 | 99 |
| Move | 88 | 98 | 97 |
| Walking | 91 | 98 | 97 |
| Running | 88 | 100 | 98 |
| BiCycling | 58 | 100 | 98 |