Virtual Reality Preparation for Medical Imaging

Movement in the MRI simulation was captured by fitting participants with a motion sensor headband (MoTrak System 1.0, Psychology Software Tools Inc). Head movement was collected at 8 samples per second, yielding approximately 3300 data points per axis per participant. The threshold for a successful MRI, as defined by the department of radiology, is approximately 3-4 mm. Consequently, if at any point during the scan the participant moved >4 mm of cumulative displacement, it was noted as a fail. Success was indicated if participants were able to complete a 6-minute head scan without surpassing 4 mm of movement at any of the 3300 data points collected. The number and percentage of participants who were successful are reported.

Child anxiety was measured with the Venham picture test (VPT; score 0-8). The level of the patient's anxiety was classified as anxiety-free (score 0), low anxiety (scores 1-3), middle anxiety (scores 4-6), and high anxiety (scores 7-8).

Caregiver anxiety was measured with the short State-Trait Anxiety Inventory (STAI; score 6-24), a 6-item, adapted version of the well-validated Spielberger STAI Scale. The short form of the STAI includes six statements. The range for the short STAI is 6 to 24 points, with 6 points signifying no anxiety and 24 points signifying the highest level of anxiety.

For measuring child satisfaction, participants were asked to indicate how satisfied they were with the preparation program by pointing to a visual analog scale ranging from 0 (terrible) to 100 (fantastic).

The caregivers of our participants were prompted to provide usability feedback on the preparation materials at the end of the study. Caregivers were asked to complete the USE (Usefulness, Satisfaction, and Ease of Use) Questionnaire administered at the end of the study activities on a tablet. The USE Questionnaire is a 7-point Likert rating scale from 1-strongly disagree to 7-strongly agree. Caregivers were asked to rate the preparation program on measures related to usefulness (5-strongly disagree to 35-strongly agree), ease of use (4-strongly disagree to 28-strongly agree), ease of learning (3-strongly disagree to 21-strongly agree), and satisfaction (5-strongly disagree to 35-strongly agree).

The assessment time was defined as the time spent in the simulated MRI room until the participant was discharged from the simulation experience, either as successful or noncompliant.

Fun was measured using the Smilyometer Likert Scale, a part of the Fun Toolkit. The Smileyometer was used before and after the children interacted with a preparation program. The rationale for using it before is that it can measure their expectations and for using it afterward is that it is assumed that the child is reporting experienced fun. After allocation to a preparatory program, children were asked how good they thought the preparation would be by pointing to the Smilyometer Likert Scale to indicate their expectation of using the intervention. After using the preparation and completing the assessment (timepoint 3 [T3]), the children were again asked how good they thought the preparation actually was using the same Smileyometer Likert scale. The Smileyometer is a Likert scale from 1 (Awful) to 5 (Fantastic).

The preparation time started when the study staff finished describing the preparation program, and the researcher indicated that it was time to begin the active preparation. The preparation time was stopped upon indication that the participant felt ready to take the assessment. This time frame was selected as it was the allotted appointment time provided by our hospital CLP to prepare patients and their families for medical imaging procedures.

We asked the children if they would recommend the preparation to a friend who needed an MRI.