Table 3.

Virtual reality details of the studies included in part 2.

Study	Target	Dosage or time in VRa and VR hardware	Task details	Outcome measures	Results	Adverse effects and potential issues	Eligibility criteria
Banville and Nolin [111]	Prospective memory and executive functions	Time in VR not reported; HMDb (eMagin Z800) with head tracker	Non-VR task: prospective memory assessment based on Rivermead Behavioral Memory Test; VR task: virtual prospective memory tasks completed in a virtual city (included visiting apartments and selecting an apartment to live in)	Non-VR: correct actions, time to complete, and whether prompting was required; VR: prospective memory score, precision score, time to complete, success in task, and IPQc	Participants could be classified as having a TBId by performance on each task. TBI participants were significantly less precise with prospective memory VR tasks (P=.02) and took more time to perform VR tasks (P=.008) than controls	SSQe completed; no reported cybersickness; SSQ scores did not differ between groups	Inclusion criteria: confirmed TBI
Cikajlo et al [101]	Stress and anxiety	8 sessions (25 minutes per session, once weekly); Samsung Galaxy X7 mobile phone mounted to HMD (Samsung Gear VR)	Mindfulness stress reduction program conducted by an instructor (eg, self-meditation and group discussions in various VEsf such as a mountain view or a room with a fireplace)	MAAS,g SWLS,h MMSEi (TBI only), session and task ratings, and head motion	Slight improvement in MAAS and SWLS scores (TBI group>non-TBI group); one participant increased MMSE (not reported for others); task ratings: simple to use and interesting; varying head motions	Potential for overheating of mobile phones (sessions were, therefore, limited to 30 minutes)	Inclusion criteria: mild or no cognitive impairment and able to understand instructions; exclusion criteria: high diopters, astigmatism, and wore glasses
Gamito et al [102]	Working memory and attention	10 sessions (5 minutes each session); HMD (eMagin Z800)	Activities included performing ADLsj in the VE (eg, breakfast, navigating to and from a supermarket, and buying items)	PASATk and completion time of each task	Significant increase in correct responses between initial and final PASAT scores (P<.05)	Not reported	Inclusion criteria: diagnosed with a TBI 3-12 months prior, clinical deficit in memory and attention, and aged 18-60 years; exclusion criteria: a previous psychiatric disorder that may impact memory and attention and neurological diseases
Ma et al [103]	Balance and functional mobility	5 sessions (12 trials, with a 1- to 2-minute break in between); breaks were decided by the participant. Samsung Galaxy X7 mobile phone mounted to HMD (Samsung Gear VR)	Standing balance exercises in a VE with traffic lights, street crossing and traffic island, night and day versions, moving cars, and static buildings	DGI,l mini-BEST,m DHI,n ABC,o GROC,p and patient-specific functional scale (self-scoring street crossing and multitasking abilities)	Improvements in DGI, mini-BEST, DHI, GROC, and patient-specific functional scale	Not reported	Not reported
Robitaille et al [112]	Executive functions	Time in VR not reported; HMD (piSight 166-43) with head tracking and body tracking (MoCap)	Exploration of a simulated military patrol scene in a village with different conditions and obstacles to navigate (eg, fences, wires, beams, and avatars)	PQ,q SUS,r errors, walking speed and fluidity, and obstacle clearance	TBI group walked faster and had slightly greater obstacle clearances. Significant difference in walking fluidity between groups for two hostile blocks (P=.046). Moderate to high presence scores on SUS and PQ	SSQ completed: 1 participant with TBI and 1 control participant reported slight headaches	Inclusion criteria (TBI): mild TBI; inclusion criteria (controls): no known TBI or other neurological or musculoskeletal issues

^aVR: virtual reality.

^bHMD: head-mounted display.

^cIPQ: Igroup Presence Questionnaire.

^dTBI: traumatic brain injury.

^eSSQ: Simulator Sickness Questionnaire.

^fVE: virtual environment.

^gMAAS: Mindfulness Attention Awareness Scale.

^hSWLS: Satisfaction With Life Scale.

ⁱMMSE: Mini-Mental State Examination.

^jADL: activities of daily living.

^kPASAT: Paced Auditory Serial Addition Task.

^lDGI: Dynamic Gait Index.

^mmini-BEST: Mini-Balance Evaluation System Test.

ⁿDHI: Dizziness Handicap Index.

^oABC: Activities Balance Confidence Scale.

^pGROC: Global Rating of Change.

^qPQ: Presence Questionnaire.

^rSUS: Slater-Usoh-Steed Questionnaire.