Table 4.

Overview of the variables and the related classification method

Category	Variable	Classification method
Research
	Year of publication	Metadata
	Geolocation	Metadata
	Number of participants	Metadata
	Participant age group	Metadata
	Medical subject headings	MeSH57
	Clinical trial	Clinical trials.gov,58 manual, binary
	Use cases identification	Manual, binary
	Evaluation	Manual, binary
AR technology
	Technology readiness level	US Department of Defense,59 manual
	AR display category	Schmalstieg and Höllerer,60 manual
	Technical challenges	Schmalstieg and Höllerer,60 manual
	AR tracking	Schmalstieg and Höllerer,60 manual
	AR taxonomy	Hugues et al,53 manual
	Interactive or haptic	Manual, binary
Patient education
	Care path	Elsevier’s conceptual framework to develop patient education content61
	Educator	Miller-Stoeckel Client Education model,62 manual
	Learner	Miller-Stoeckel Client Education model,62 manual
	Educator–learner relationship	Miller-Stoeckel Client Education model,62 manual
	Patient education outcomes	Miller-Stoeckel Client Education model,62 manual
	Learning theory	Manual, binary
	Learning strategy	Manual
	Learning styles	Manual
	Teaching techniques	Manual

AR, augmented reality.