Table 10.

DDD systems comparison, based on practicality.

	Practicality Features	Intrusiveness	Invasiveness	Reported Accuracies in DDD Literature	Cost	Ease of Use
DDD Systems Types
Image-based systems		Non-intrusive	Non-invasive	High accuracy, between 72.25–99.59%	Generally low-cost	Automatic—no required set up or user intervention
Biological-based systems		Depends on the hardware and method used	Depends on the hardware and method used	High accuracy, between 70–97.19%	Expensive when high-quality sensors are used	May require set up, user intervention, or wearing sensors
Vehicle-based systems		Non-intrusive	Non-invasive	Low accuracy, as low as 62.1%	Mostly comes as an expensive car accessory	Automatic—no required set up or user intervention
Hybrid-based systems		Depends on the hardware and method used	Depends on the hardware and method used	High accuracy, between 79–99%	Cost depends on the used hardware	May require set up, user intervention, or wearing sensors