Table 2.

Description of camera-assisted observation studies.

Paper and system description			Device location	Video type	System type	System metrics (hand hygiene opportunities)
Auditor (human)
	Brotfain et al [34]
		RGBa camera	Patient room	Streaming	Research	WHOb 5 moments
	Sánchez-Carrillo et al [35]
		RGB camera	Patient room	Recorded	Research	WHO 5 moments
	Diller et al [36]
		RGB camera (with infrared lens)	Patient room	Recorded	Research	WHO 5 moments
	Armellino et al [38,39]
		RGB camera	Sink and sanitizer dispenser	Recorded	Commercial (Arrowsight)	Patient room entry/exit events
		Motion sensor	Patient room entrance	Recorded	Commercial (Arrowsight)	Patient room entry/exit events
	Diefenbacher et al [37,40]
		RGB camera	HCWsc (chest)	Recorded	Research	WHO 5 moments
Auditor (algorithm)
	Zhong et al [41]
		RGB camera	HCWs (chest)	Recorded	Research	Hand hygiene events
	Snoek et al [42]
		RGB camera	Sink	Recorded	Research	Hand hygiene events (5 states related to faucet interaction)
		Microphone	Sink	Recorded	Research	Hand hygiene events (5 states related to faucet interaction)
	Awwad et al [43]
		RGB depth camera	Patient bed	Recorded	Research	Moment 1 (before touching a patient)

^aRGB: red green blue.

^bWHO: World Health Organization.

^cHCW: health care worker.