Virtual Reality and Human Subjects Research

Virtual reality (VR) is created by tracking users’ natural movements (such as head rotation, arm movement, or walking) and rendering a digital environment in response to these movements. Unlike augmented reality (AR), VR is intended to immerse users in a virtual space and replace cues from the real world with digital ones. Note that many inexperienced researchers use the label “VR” when they are not employing VR; they are using desktop monitors with 3D virtual worlds or video games.

The risks of VR studies are contingent on several factors. The equipment used, the type of interaction, the length of treatment, the content delivered, and individual differences (both ongoing conditions and temporary states) can affect a participant’s likelihood to experience side effects when using VR.

Thus, it is important to know what equipment researchers plan on using and what the physical space of the study will be. Will people be wearing a headset, or is it projection based? Will people be walking around a space or seated? Will other equipment be incorporated (controllers, backpacks, sensors/trackers)? Are they in a controlled lab setting or elsewhere? What is the space like? It is also imperative for researchers to screen participants for conditions that may make them very prone to negative side effects.

The following guide is intended to help researchers conduct sounder, safer human subjects research using VR equipment. There is also a section specific to completing IRB applications for studies using VR.

Managing Risks in VR Research

Many people are unaware of the various risks associated with VR equipment and immersion. These include:

cybersickness
triggering of seizures or other conditions due to visual effects
injury from tripping, falling, or colliding with physical objects
contagions from sharing head-mounted displays

Cybersickness is a common side effect of VR immersion. Symptoms include:

headache
feeling dizzy or lightheaded
sudden drowsiness or fatigue
vision problems
nausea and vomiting

Risk Mitigation

The following list explains practices that can mitigate risks associated with VR studies.

The area should always be cleared of hazards and obstacles that could harm participants during immersion (e.g., tripping hazards such as wires or rugs). Tile floors should be kept dry. Researchers should know where the nearest restroom is and be prepared to accompany the participant if needed. It is recommended that spaces are equipped with a lined trash can or emesis bags in case of vomiting. Researchers may wish to keep ginger ale or saltines on hand to settle upset stomachs.
Before immersion, every participant should be prescreened for long-term and short-term conditions and excluded as appropriate.
Immediately before immersion participants should be reminded that they can stop any time and should tell the researcher immediately if they are feeling any symptoms.
During immersion, the researcher should conduct welfare checks on participants and schedule breaks for longer periods of immersion. Keep in mind children and adults with cognitive impairments may not recognize the bodily onset of cybersickness. Different approaches may be necessary depending on the age and background of the children. If the participant reports any symptoms, the researcher should have the participant take a break from or terminate immersion.
During immersion one researcher should always be watching and monitoring the participant. Sufficient precautions should be taken to ensure they do not harm themselves (e.g., running into walls, furniture, or other participants). If the participant is moving around the room and their vision is obscured by a headset, the study may need a “catcher,” or someone to follow the person around the room. Wired headsets can present tripping hazards; wireless headsets mean there is one less constraint keeping participants from running into a wall.
After immersion, the researcher should ensure the participant is not feeling any side effects. If they are, researchers should render care and monitor the participant as needed.
Appropriate materials should be on hand to clean equipment to minimize the possibility of contagions.

Prescreening & Eligibility Criteria

Prescreening should be conducted before immersion. Researchers should consider:

Pre-existing conditions that may increase the likelihood of side effects
States that may increase the likelihood of side effects
As relevant to the study, visual impairments or physical mobility

Optimally screening for long-term conditions would happen before participants are on site for the study. Regardless of prescreening for long-term conditions, physical state should also be assessed immediately preceding immersion.

Longer-term conditions that may promote a greater likelihood of experiencing side effects include:

a history of motion sickness or nausea
a history of migraines or headaches
a history of balance issues or dizziness
epilepsy or neurological conditions where visual stimuli may trigger seizures or other issues
pregnancy, recent concussions, or other conditions where dizziness, nausea, or
headaches are more likely

Short-term (state) conditions include:

headache
nausea
dizziness or lightheadedness
recent illness (flu, hangover, etc.)
recent contagious condition (pinkeye, head lice, flu, etc.)

Monitoring During VR Immersion

In many studies, researchers do not wish to interrupt a VR experience. Researchers should think ahead to best plan their studies to balance this desire with the need to prevent participants from experiencing negative side effects.

Any treatment over a few minutes in length should include wellness checks. Equipment or content that is more likely to evoke cybersickness should be considered when determining the frequency and timing of these checks. Additionally, if participants indicate higher potential for cybersickness in their prescreenings, these checks may need to be earlier or more frequent during immersion. Keep in mind some people may be so engaged in the experience that they do not recognize the onset of cybersickness before it’s too late.

Optimally a check would be administered by having the participant stop, sit down if they are not seated, and close their eyes to promote greater bodily awareness. At the very least, have the participant be still. Then administer a verbal check such as:

“We’re going to pause here for a minute. How are you feeling? Are you getting a headache or feeling dizzy, drowsy, or nauseated?”

Others, such as children or decisionally-impaired adults, may not recognize the bodily onset of cybersickness. Different approaches may be necessary depending on the age and background of the children. For example, you may need to ask them to focus more specifically on a part of their body.

“How does your head feel? Does it hurt? Do you feel dizzy?”

“How does your tummy feel? Does it feel OK or are you feeling yucky?”

“Do you feel funny?”

If participants are feeling unwell, one of two courses of action should be taken. In most cases, the treatment should be terminated by the researcher immediately. Termination is always recommended for children or decisionally-impaired adult participants. Otherwise, participants should be asked if they wish to continue or if they wish to stop the VR experience. If they wish to continue, a break is advised until their symptoms resolve. When they are back in VR, they should be reminded to speak up the moment they do not feel well. The frequency of wellness checks should also be increased by the experimenter.

Monitoring After VR Immersion

After immersion, researchers should ensure that participants are not experiencing any of these side effects. Collecting baseline data before immersion and followup data after immersion is optimal so that changes can be observed. An example:

Please take a moment to consider how you feel and any physical issues you are experiencing. Please indicate the extent to which you are experiencing the following right now:
(0 = Not at all; 1 = Slightly; 2 = Somewhat; 3 = Moderately; 4 = Very much)

lightheadedness
dizziness
headache
nausea
vision problems (blurriness, difficulty focusing, etc.)
upset stomach
drowsiness or fatigue

At the very least, researchers should administer a verbal check following immersion. “Are you feeling okay after the VR experience? Are you experiencing a headache, dizziness, nausea, vision problems, or sudden fatigue?”

If participants are feeling unwell, the researcher should take appropriate steps to address the situation as symptoms could get worse after leaving the study. Participants who are feeling dizzy, for example, could fall down the stairs or faint. Participants who are experiencing dizziness or lightheadedness should be encouraged to sit down or perhaps close their eyes and put their head down. If they are experiencing nausea or an upset stomach, have them sit close to the trash can or offer an emesis bag. You may wish to offer them saltines or ginger ale. Inform them that you would like them to stay until their symptoms subside and offer them a comfortable place to wait. Of course, you cannot force them to stay; if they wish to leave, express your concerns but allow them to leave.

Recommendations for IRB Applications for VR Research

This provides some guidance about places in the IRB protocol you need to address the use of VR. Keep in mind that each study is different, however, so this list may not be comprehensive for your specific needs.

Main application

Research methods: Prescreening procedure and all VR procedures should be described in detail. What equipment is being used? How long is immersion? What tasks are being performed while immersed vs. outside of VR? Are participants seated or moving around a physical space?

Research methods checklist: Please select “other” and describe the VR equipment you are using (e.g., head-mounted display; eye-tracking HMD; tracking cameras; body sensors/trackers)

Participant recruitment and selection: In this section, describe the prescreening process that will be used and how eligibility for participation will be determined.

Confidentiality of data: What kind of data is being collected by the VR system (e.g., tracking position, eye movement)? Where is it being stored and is it identifiable?

Risks: The application should clearly state risks specific to the study and also describe how they will be addressed and mitigated.

Materials

Recruitment: Recruitment materials should be clear about the use of VR equipment and eligibility criteria.

Questionnaires/survey items: This should include all prescreening questions as well as other items used for monitoring.

Consent: The Procedures/Tasks section should be clear about the use of VR equipment. The risks (described above) should be clearly stated in the Risks & Benefits section.

Unanticipated Adverse Events

If there is an unanticipated adverse event that indicates an increased risk to participants, the IRB must be notified promptly. Learn more information about event reporting.

Prescreening Questions for Pre-existing Conditions/Eligibility Criteria

Ideally, these questions are administered before participants are scheduled for participation or arrive at the study location, as their responses may disqualify them from participation. Because of variations in equipment (e.g., is it a projection system or a head-mounted display?), interaction (e.g., are participants sitting or walking?), and content, there may be different levels applied for some of these questions. Recommendations are provided for guidance.

Do you experience motion sickness or car sickness?
0 Never
1 Has happened once or twice
2 Rarely
3 Sometimes
4 Often
5 Very often

Recommendation: Participants who indicate 4 or 5 are not recommended for use in most VR studies. Participants who indicate 3 should be carefully considered based on equipment and content.

Do you have any conditions that where flashing or intense light might affect you, such as epilepsy, migraines, unexplained seizures, recent concussions, or light sensitivity?
Yes
No
Please explain:

Recommendation: In most cases, a ‘yes’ response should disqualify participants.

Do you have any neurological or vestibular issues or, have you had any recent experiences (e.g., a head injury) that affect your balance or gait?
Yes
No
Please explain:

Recommendation: In most cases, a ‘yes’ response should disqualify participants. ‘Yes’ should disqualify anyone from a study where they are walking around.

Do you have any uncorrected vision impairments, such as blindness, partial blindness, limited field of view, blurred vision, or stereoblindness? That is, do you have any issues affecting your vision that are not corrected with contacts, glasses, etc.?
Yes
No
Please explain:

Do you have any issues affecting your physical mobility or body movements?
Yes
No
Please explain:

Have you ever experienced virtual reality (VR)?
Yes, and I had no physical side effects.
Yes, and I had some physical side effects.
No
Please explain:

Recommendation: You may wish to use more specific questions here about specific equipment or content they have experienced. Some people will not understand what “VR” means and may describe typical desktop computer use or video games.

More specific vision questions that may influence study-specific eligibility:

Do you experience blindness or issues affecting your field of view? Yes No Unsure
Please explain:

Do you experience colorblindness or issues with color perception? Yes No Unsure
Please explain:

Do you experience stereoblindness or issues with depth perception? Yes No Unsure
Please explain:

Note: You may wish to administer more nuanced tests of color acuity or stereoblindness in person, particularly for a study concerned with visual or visuospatial outcomes.

More specific questions for physical mobility that may influence study-specific eligibility:

Do you have any issues affecting your ability to move your head and look around?
Yes
No
Please explain:

Do you have any issues affecting your ability to move your upper body, hands, or fingers, such as lifting your arms, grasping objects, etc.?
Yes
No
Please explain:

Do you have any issues affecting your ability to walk?
Yes
No
Please explain:

Additional Reading

Bouchard, S., Robillard, G., Renaud, P., & Bernier, F. (2011). Exploring new dimensions in the assessment of virtual reality induced side effects. Journal of Computer and Information Technology, 1, 20-32.
Golding, J. F. (1998). Motion sickness susceptibility questionnaire revised and its relationship to other forms of sickness. Brain Research Bulletin, 47, 507-516. doi: 10.1016/S0361-9230(98)00091
Golding, J. F. (2006). Predicting individual differences in motion sickness susceptibility by questionnaire. Personality and Individual Differences, 41, 237-248. doi: 10.1016/j.paid.2006.01.012
Kennedy, R. S., Drexler, J., & Kennedy, R. C. (2010). Research in visually induced motion sickness. Applied Ergonomics, 41, 494-503. doi: 10.1016/j.apergo.2009.11.006
Kennedy, R. S., Lane, N. E., Berbaum, K. S., & Lilienthal, M. G. (1993). Simulator sickness questionnaire: An enhanced method for quantifying simulator sickness. The International Journal of Aviation Psychology, 3, 203-220. doi: 10.1207/s15327108ijap0303_3