This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Virtual Reality in the Operating Room (NCT03614325), a randomized na study. The primary outcome is Intraoperative Propofol Dose.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03614325 |
| Phase | NA |
| Condition | Anesthesia, Intravenous, Pain, Postoperative, Delayed Recovery From Anesthesia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 40 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Beth Israel Deaconess Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing hand or wrist operations were the intended population. The registry describes the trial as investigating virtual reality relaxation during hand and arm operations. It does not report additional eligibility criteria or the characteristics of the participants contributing to the primary endpoint.
Intervention
The experimental group wore a headset during surgery and experienced an immersive virtual reality environment. The registry describes short videos and environments intended to promote relaxation and calmness. Details beyond this description are not reported in the registry record.
Comparator
The comparison was usual anesthesia care for hand or wrist surgery and postoperative recovery. Participants in that arm were asked not to use a virtual reality headset during surgery. The registry identifies the study as randomized, controlled, and parallel-group.
Primary question
The primary endpoint was intraoperative propofol dose, reported in mg/kg/min as a median with an interquartile range over a 60-minute timeframe. The trial was designed to investigate whether immersive relaxation could accompany a relaxing operating-room experience while potentially reducing anesthesia requirements. The posted endpoint is a dose measure; it does not directly measure relaxation.
3. Trial Design
NCT03614325, titled “Virtual Reality in the Operating Room,” is recorded as a completed randomized controlled trial sponsored by Beth Israel Deaconess Medical Center. The record gives a parallel-group model and single masking. It does not identify who was masked, so the masking label alone does not establish whether participants, clinicians, outcome assessors, or another group were unaware of assignment. The phase is recorded as NA.
The registry lists enrollment of 40. The primary endpoint results include 17 participants in the usual anesthesia care arm and 17 in the virtual reality immersive relaxation arm. These endpoint counts are distinct from the enrollment figure; the reasons for the difference and the analysis population are not reported in the registry record. Safety figures use separate at-risk counts for each arm.
The control arm followed usual care and was asked to refrain from using a headset during surgery. The experimental arm used a headset and virtual environment during surgery. The registry describes the intervention as an adjunct to anesthesia, but details of anesthesia management beyond the stated endpoint and arm descriptions are not reported in the registry record.
The record gives a start date of 2018-12-04, a primary completion date of 2019-11-07, and completed status. It lists eight secondary outcomes, including other intraoperative anesthetics or analgesics, propofol dose, recovery-room stay, pain, satisfaction, survey responses, and hand disability measures. Numerical secondary-outcome details and the statistical analysis plan are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Overall Study
| Stage | Usual Anesthesia Care | Virtual Reality Immersive Relaxation |
|---|---|---|
| STARTED | 20 | 20 |
| Completed Intervention | 17 | 17 |
| COMPLETED | 15 | 16 |
| NOT COMPLETED | 5 | 4 |
Reasons for not completing this period:
| Reason | Usual Anesthesia Care | Virtual Reality Immersive Relaxation |
|---|---|---|
| Withdrawal by Subject | 0 | 2 |
| Surgery Cancelled | 2 | 1 |
| Lost to Follow-up | 2 | 1 |
| Surgery never scheduled | 1 | 0 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Usual Anesthesia Care | Virtual Reality Immersive Relaxation | Total |
|---|---|---|---|---|
| Participants analysed | 17 | 17 | 34 | |
| Age, Continuous | years | 50.1 (SD 11.1) | 48.7 (SD 19.0) | 49.4 (SD 0.09) |
| Sex: Female, Male: Female | Participants | 8 | 5 | 13 |
| Sex: Female, Male: Male | Participants | 9 | 12 | 21 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 | 2 | 4 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 15 | 15 | 30 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Body Mass Index | Kg/m^2 | 28.7 (SD 5.2) | 28.1 (SD 4.8) | 28.4 (SD .12) |
| Diabetes | Participants | 4 | 2 | 6 |
| Hypertension | Participants | 6 | 9 | 15 |
| Dyslipidemia | Participants | 6 | 5 | 11 |
| Obesity | Participants | 7 | 3 | 10 |
| COPD | Participants | 4 | 3 | 7 |
| Depression | Participants | 6 | 3 | 9 |
| Anxiety | Participants | 3 | 2 | 5 |
| Previous Use of VR: Never | Participants | 13 | 10 | 23 |
| Previous Use of VR: Once | Participants | 2 | 3 | 5 |
| Previous Use of VR: A few times | Participants | 1 | 4 | 5 |
| Previous Use of VR: Many times | Participants | 1 | 0 | 1 |
| Procedure Type: Carpal Tunnel | Participants | 4 | 4 | 8 |
| Procedure Type: Dupuytren's contracture | Participants | 1 | 2 | 3 |
| Procedure Type: Tendon/ligament repair | Participants | 5 | 3 | 8 |
| Procedure Type: Ganglion removal | Participants | 3 | 3 | 6 |
| Procedure Type: Ulnar neurolysis/decompression | Participants | 2 | 4 | 6 |
| Procedure Type: Mass/cyst excision | Participants | 3 | 1 | 4 |
| Procedure Type: Reduction and/or internal fixation | Participants | 2 | 3 | 5 |
| Procedure Type: Other | Participants | 4 | 2 | 6 |
| Surgery Length | minutes | 27.0 (16.5 to 45.5) | 19.0 (12.5 to 51.0) | 23 (14.5 to 48.25) |
6. Primary Endpoint
The registry lists the primary outcome as Intraoperative Propofol Dose, measured over 60 minutes.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | mg/kg/min |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is total intraoperative propofol dose, expressed in mg/kg/min, measured over the listed 60-minute timeframe. Propofol is an anesthetic drug, so its administered dose is a direct measure of one aspect of anesthesia use during the procedure. The trial’s stated rationale was to investigate whether virtual reality immersive relaxation could potentially reduce anesthesia requirements while supporting a relaxing operating-room experience.
The endpoint is reported separately for usual anesthesia care and virtual reality immersive relaxation. The registry identifies the summary statistic as a median and the measure of spread as an interquartile range. The posted values are 0.14 mg/kg/min, with an interquartile range of 0.12 to 0.21, for usual care; and 0.0 mg/kg/min, with an interquartile range of 0.0 to 0.01, for virtual reality. These summaries describe the observed distributions in the participants included in each arm’s endpoint result.
Dose is not itself a measure of patient-reported relaxation, pain, satisfaction, or recovery. Those topics appear among the listed secondary outcomes, but their numerical results are not included in the primary endpoint figures described by the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary result is descriptive. The median propofol dose is 0.14 mg/kg/min in the usual anesthesia care arm, with an interquartile range of 0.12 to 0.21. In the virtual reality immersive relaxation arm, the median is 0.0 mg/kg/min, with an interquartile range of 0.0 to 0.01. The endpoint counts are 17 participants in each arm. These figures describe the reported central values and spread; they do not establish the precision or statistical significance of a between-arm effect.
An interquartile range describes the middle half of the observed values, from the lower to the upper quartile. It is a measure of spread, not a confidence interval for an arm’s median and not a confidence interval for the difference between arms. The registry reports no confidence interval or inferential test for the primary comparison. A p-value and an adjusted effect estimate are not reported in the registry record. Therefore, the posted summaries alone do not quantify uncertainty around the difference between treatment groups.
The arm medians are visibly different in the posted summaries, but the record does not provide participant-level values, a formal comparison, or enough information to independently assess the distributional shape. A median displayed as 0.0 should be read at the precision reported; it does not establish that every participant in that arm received no propofol. The interquartile range for that arm extends from 0.0 to 0.01, which also indicates that the summary contains values above the displayed median.
The interpretation is also limited by the endpoint counts. Although enrollment is 40, the primary endpoint results list 17 participants per arm. The relationship between enrollment and those endpoint counts, including exclusions or missing observations, is not reported in the registry record. The results therefore apply directly to the participants represented in those arm summaries, while the extent to which they represent all enrolled participants cannot be determined from the record.
No conclusions about patient relaxation, satisfaction, pain, recovery, or overall anesthesia use should be drawn from this endpoint alone. Those outcomes are listed separately, and their numerical results are not reported in the endpoint data. The registry’s stated purpose and the posted dose summaries are related, but the dose summaries do not by themselves resolve the broader clinical question.
9. Statistical Methods Explained
Why report a median?
The median is the middle value when observations are ordered. It can be useful when data are skewed or include unusually high or low observations, because it is less influenced by extremes than the arithmetic mean. This is a general statistical explanation, not a statement about the observed shape of the propofol data in this trial. The registry identifies the primary endpoint summary as a median but does not report a distribution plot or participant-level data in the registry record.
The reported medians are 0.14 mg/kg/min for usual anesthesia care and 0.0 mg/kg/min for virtual reality immersive relaxation. These are summaries for the participants counted in each arm’s primary endpoint result. They do not describe every individual observation, and they do not give a direct estimate of uncertainty for a treatment-group contrast.
What does the interquartile range describe?
The interquartile range runs from the lower quartile to the upper quartile and contains the middle half of observed values. It communicates variability around the median without specifying the full range. The posted interval is 0.12 to 0.21 for usual anesthesia care and 0.0 to 0.01 for virtual reality immersive relaxation. These intervals are not confidence intervals. A confidence interval is a statistical range intended to express uncertainty about an estimated quantity, such as a population median or a difference between groups. No confidence interval for the primary comparison is reported in the registry record.
The reported precision also matters. Values are displayed as rounded summaries, and the virtual reality median is shown as 0.0. That displayed value should not be interpreted as evidence that all participants had an identical dose or that all received no propofol. The reported interquartile range includes an upper quartile of 0.01. More detailed values and the rounding procedure are not reported in the registry record.
Why does the comparison need an inferential analysis?
In a randomized trial, an observed difference between arm summaries can reflect a treatment effect, chance variation, or both. An inferential analysis estimates how compatible the observed data are with a specified statistical model and quantifies uncertainty. A confidence interval for a between-arm contrast would show a range of estimates consistent with the data and model; a hypothesis test could provide a p-value for a stated null hypothesis. Neither a primary comparison estimate nor its uncertainty is reported. The arm summaries alone therefore do not establish whether the observed difference is distinguishable from chance variation.
Random allocation supports a fair comparison in expectation, but does not guarantee that the groups are identical in a particular trial. This general point is especially relevant when interpreting any trial result: group sizes, baseline characteristics, adherence, outcome availability, and analysis choices can affect precision and interpretation. Baseline characteristics and details needed to assess those features are not reported in the registry record details.
What do the planning illustrations mean?
The registry record describes planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. The illustrated effect to detect is a stated fraction of the observed effect. Such calculations describe hypothetical future sample-size requirements under their assumptions; they do not show the probability that this completed trial detected an effect. Sample-size calculations based on an observed effect can be sensitive to the size of that estimate, so they should be read as planning illustrations rather than as evidence about the trial’s achieved power. The record does not report the trial’s own sample-size justification, and the planning assumptions do not establish what rationale governed enrollment.
In general, power is a design quantity defined for a particular assumed effect, variability, significance threshold, and analysis. It is not a retrospective measure of whether a study result is true. Because the posted primary comparison has no reported inferential test or confidence interval, the planning illustration should not be used to substitute for an estimate of the uncertainty in the observed comparison.
What can be concluded from the posted statistical details?
The primary summaries permit a descriptive comparison of the two reported medians and their interquartile ranges. They do not identify the test used, any covariate adjustment, handling of repeated measurements, or whether a prespecified analysis differed from the posted summaries. Those details are not reported in the registry record. The statistical analysis plan is not reported in the registry record, so the available information does not support reconstructing analysis choices or determining whether the displayed summaries were the planned primary analysis.
General statistical practice distinguishes between describing observed data and making an inferential claim about a population or treatment effect. Here, the medians and interquartile ranges are descriptive. The lack of a reported inferential comparison means that the magnitude and precision of a treatment-group contrast cannot be evaluated from these summaries alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary outcome and eight secondary outcomes. The secondary topics include other intraoperative anesthetics or analgesics, total intraoperative propofol, length of recovery-room stay, pain, satisfaction, survey responses, and hand-disability measures. Considering many outcomes can raise a multiplicity issue: when several statistical tests are conducted, the chance of at least one apparently unusual result can increase. General approaches include defining a primary outcome in advance, setting an order for testing, or adjusting inference across multiple comparisons. The planned approach to multiplicity is not reported in the registry record.
The primary endpoint results give counts of 17 participants in each arm, while enrollment is 40. The registry record does not explain why the endpoint counts differ from enrollment, identify the analysis population, or describe how missing outcome data were handled. It does not report whether participants were analyzed according to randomized assignment, whether any participants were excluded, or how protocol deviations were treated. These points matter because analysis populations and missing-data methods can affect the interpretation of randomized comparisons.
The record lists eight secondary outcomes, but numerical results and analysis details for those outcomes are not included in the registry record. The statistical analysis plan, prespecified hierarchy among endpoints, and any adjustments for multiple testing are not reported in the registry record. The record also reports zero analyses in its analysis listing, so no inferential analysis is available there to assess.
General statistical interpretation should distinguish an unreported analysis from evidence that no analysis was conducted. The registry does not provide enough detail to resolve that distinction. The available primary result is best treated as a descriptive arm summary, without claims about adjusted significance or multiplicity-controlled inference.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Usual Anesthesia Care | 0 | 19 | 0.0% |
| Virtual Reality Immersive Relaxation | 0 | 20 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Usual Anesthesia Care | 0 of 19 |
| Virtual Reality Immersive Relaxation | 0 of 20 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Usual Anesthesia Care | 0 of 19 |
| Virtual Reality Immersive Relaxation | 0 of 20 |
The registry reports serious adverse events for the usual anesthesia care arm among 19 participants at risk and for the virtual reality immersive relaxation arm among 20 participants at risk. The serious adverse event count is 0 in each arm. The record also reports 0 other adverse events in each arm and 0 deaths in each arm.
These are counts as recorded for the stated at-risk groups. They do not establish that an intervention is safe or that no adverse events could occur. A count of zero in a trial does not show that the underlying risk is zero; it indicates that no events in the specified category were recorded among the listed participants at risk during the period captured by the registry record. The period and detailed event-collection procedures are not reported in the registry record details.
The registry lists no top serious adverse event terms. With no event counts in either arm, there are no specific serious event categories to describe from this record. The safety figures should be read alongside the endpoint results as a separate descriptive part of the trial record, not as a statistical test of comparative safety.
12. What the Result Does, and Does Not, Mean
The result documents a difference between the reported arm-level medians for intraoperative propofol dose. The usual anesthesia care median is 0.14 mg/kg/min, with an interquartile range of 0.12 to 0.21; the virtual reality immersive relaxation median is 0.0 mg/kg/min, with an interquartile range of 0.0 to 0.01. Each arm’s primary endpoint result includes 17 participants. Those data describe the posted observations but do not quantify the uncertainty around a treatment-group contrast.
The result does not, by itself, establish that virtual reality caused the difference. The registry record does not report an inferential comparison, confidence interval, or p-value for the primary endpoint. It also does not provide the analysis population details or an explanation for why the endpoint counts are lower than enrollment. These omissions prevent a full assessment of the precision and scope of the comparison.
The endpoint is a measure of propofol dose, not a direct assessment of whether participants felt relaxed or whether the operating-room experience was acceptable. The trial’s stated purpose includes the possibility of a relaxing experience and potentially reduced anesthesia requirements, but the primary endpoint only addresses the dose measure. Satisfaction, pain, recovery, and hand disability appear among the secondary outcomes, and their numerical results are not reported in the record details.
The safety record reports no serious adverse events, other adverse events, or deaths in the listed at-risk groups. Those counts are descriptive and do not demonstrate an absence of risk. The study’s completed status indicates that the registry marks the trial as completed; it does not change the limits of the posted outcome information.
Overall, the record supports a narrow statement: the two arms have different posted median propofol-dose summaries among the participants counted for that endpoint. It does not support a conclusion about statistical significance, a broader clinical effect, or the full balance of benefits and risks.
13. Why This Trial Matters Statistically
This trial is statistically interesting because its primary endpoint is a treatment-use measure rather than a direct report of pain, relaxation, or satisfaction. Intraoperative propofol dose can describe one component of anesthesia administration, while the trial’s stated motivation also concerns the patient’s operating-room experience. Keeping those concepts separate is important: a difference in dose summaries would not, on its own, establish a difference in patient experience.
The record also illustrates why descriptive summaries and inferential comparisons answer different questions. Medians and interquartile ranges characterize the observed arm data, but they do not show the uncertainty around the contrast. Without a reported comparison estimate and confidence interval, readers cannot assess how precisely the posted summaries distinguish the groups. A formal analysis would need to be interpreted alongside the endpoint counts, analysis population, and prespecified methods, details that are not reported in the registry record.
There is a further distinction between enrollment and endpoint availability. The record lists enrollment of 40 but reports primary endpoint counts of 17 per arm. Explaining that difference would help readers understand which participants contributed to the main result and whether missing observations could affect interpretation. The record does not provide that explanation.
Finally, the study lists several secondary outcomes that address different aspects of the surgical and recovery experience. Without their numerical results and a stated multiplicity strategy, the primary endpoint cannot stand in for the full set of questions the trial was designed to explore. These features make the registry record a useful example of why endpoint definitions, analysis populations, uncertainty estimates, and transparent reporting all matter when reading a clinical trial.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation of the posted primary result is that it contains arm-level medians and interquartile ranges without a reported between-arm estimate, confidence interval, or p-value. This prevents assessment of the statistical precision of the contrast. The record does not identify the inferential test or any adjustment used for the primary endpoint.
The primary endpoint counts are 17 per arm, whereas enrollment is 40. The reasons for the different counts, the analysis population, and the handling of missing data are not reported in the registry record. Without that information, it is not possible to assess whether the endpoint summaries represent all randomized participants or how unavailable outcomes may have influenced the result.
The record describes single masking but does not identify who was masked. It also does not report the statistical analysis plan, the sample-size justification used for the trial, baseline characteristics, or details of adherence and protocol deviations. These gaps limit evaluation of design and analysis decisions. The separate planning illustrations are based on the observed effect and stated assumptions; they are not a substitute for the trial’s own design rationale or an estimate of achieved power.
The registry lists eight secondary outcomes, but numerical secondary results are not present in the registry record. The planned approach to multiple testing is also not reported. As a result, the primary dose endpoint cannot answer the broader questions about patient-reported relaxation, satisfaction, pain, recovery, or hand disability. The reported adverse-event counts are zero in the listed categories, but details about the event-collection period and procedures are not reported in the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Virtual Reality in the Operating Room — NCT03614325.
- Registry record last updated 2024-04-08; status last verified 2023-10.
- Results first posted 2024-04-08.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT03614325 is a completed randomized, parallel-group trial sponsored by Beth Israel Deaconess Medical Center. It compared usual anesthesia care with virtual reality immersive relaxation during hand or wrist surgery. The registry lists enrollment of 40, single masking, and a primary completion date of 2019-11-07.
The primary endpoint was intraoperative propofol dose in mg/kg/min over a 60-minute timeframe. The usual-care arm had a median of 0.14 and interquartile range of 0.12 to 0.21 among 17 participants. The virtual reality arm had a median of 0.0 and interquartile range of 0.0 to 0.01 among 17 participants. No inferential comparison is reported in the registry record.
The record lists eight secondary outcomes and reports zero serious adverse events, other adverse events, and deaths in both arms among the stated at-risk groups. Numerical secondary results, the analysis population details, missing-data methods, and the statistical analysis plan are not reported in the registry record.