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 Sevoflurane Concentrations in Children (NCT06510803), a registered phase not stated study. The primary outcome is Ratios of the Inspired to Expired Sevoflurane Concentrations During Induction of Anesthesia.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT06510803 |
| Phase | Phase not stated |
| Condition | Anesthetic, Sevoflurane, Age |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 24 |
| Arms in the primary outcome | n/a |
| Lead sponsor | State University of New York at Buffalo |
| Results posted | Yes |
2. Clinical Question
Population
Children undergoing induction of anesthesia. The registry record lists an enrollment of 24 participants. Further eligibility details, including age limits and other inclusion or exclusion criteria, are not reported in the registry record.
Intervention
Induction using the Drager Apollo workstation, with sevoflurane concentrations recorded during the induction period.
Comparator
Induction using the GE Ohmeda workstation. The record labels this arm as control, but allocation is not stated, so the arms should not be interpreted as a randomized, like-for-like comparison.
Primary question
How do the ratios of inspired to expired sevoflurane concentrations change during the first 10 minutes of induction, and how do the recorded ratios compare between the two workstation groups?
The registry describes monitoring sevoflurane concentrations during induction, alongside vital signs and other recorded information. The primary outcome is a continuous measure: the inspired concentration divided by the expired concentration at repeated measurement times. The comparison therefore concerns the recorded concentration pattern over time, rather than a single outcome measured once.
The clinical question is descriptive and comparative. The record identifies two workstation groups and describes a repeated-measures analysis, but does not state how participants were assigned to the groups. It also does not report numerical primary-outcome results. Consequently, the registry record cannot establish the size, direction, or precision of any difference between workstations. Other eligibility details and the specific circumstances of induction are not reported in the registry record.
3. Trial Design
The study, titled “Sevoflurane Concentrations in Children,” is registered as NCT06510803 and is marked completed. The registry lists an enrollment of 24. The recorded start date is 2024-09-18, and the primary completion date is 2024-10-24. The sponsor is State University of New York at Buffalo.
The two arms are described by workstation: the GE Ohmeda workstation is labelled control, and the Drager Apollo workstation is labelled intervention. Both descriptions concern sevoflurane wash-in during induction of anesthesia. Although the registry gives these arm labels, allocation is not stated. The record therefore does not establish that assignment was randomized, and it specifically cautions that the arms are not a like-for-like control comparison. The reason for the allocation approach and any baseline comparability information are not reported in the registry record.
The study description says that sevoflurane concentrations and vital signs, along with the child's date of birth and type of surgery, will be recorded during the first 10 minutes of anesthesia. For the primary outcome, the record describes measurements of inspired and expired concentrations at 30-second intervals during the first 5 minutes and then every minute until the IV is secured. The stated primary-outcome timeframe is from 0 to 10 minutes of induction. The precise timing of the final measurement relative to that timeframe is not reported in the registry record.
The primary outcome is reported as means and standard deviations at measurement times. The described analysis is a two-factor repeated-measures ANOVA with the Sidak test for multiple comparisons. The registry lists four outcome measures and zero analyses. It does not report numerical results for the primary or secondary outcomes, participant flow, or details of the analysis population.
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 | Control is GE Ohmeda Workstation | Intervention is Drager Apollo Workstation |
|---|---|---|
| STARTED | 12 | 12 |
| COMPLETED | 12 | 12 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Table of the inspired to expired sevoflurane concentration ratios for the GE Ohmeda and Drager Apollo workstations during the first 10 minutes. Analysis was by two-factor repeated measures ANOVA and the Sidak test for multiple comparisons.
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.
Population: All children irrespective of sex, race and ethnicity were enrolled. All children were required to be 2 to \<7 years of age.
| Characteristic | Unit | Control is GE Ohmeda Workstation | Intervention is Drager Apollo Workstation | Total |
|---|---|---|---|---|
| Participants analysed | 12 | 12 | 24 | |
| Age, Customized: Age | years | 3.6 (SD 1) | 4.2 (SD 1.6) | 3.9 (SD 1.3) |
| Sex: Female, Male: Female | Participants | — | — | 0 |
| Sex: Female, Male: Male | Participants | — | — | 0 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Ratio of alveolar to inspired sevoflurane concentrations | ratio | 0 (SD 0) | 0 (SD 0) | 0 (SD 0) |
6. Primary Endpoint
The registry lists the primary outcome as Ratios of the Inspired to Expired Sevoflurane Concentrations During Induction of Anesthesia, measured over From 0 to 10 minutes of induction of anesthesia.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | ratio |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is the ratio of inspired to expired sevoflurane concentrations during induction of anesthesia. It is a continuous measure, and the registry describes reporting its mean and standard deviation at repeated measurement times. The stated timeframe is from 0 to 10 minutes of induction.
Inspired concentration refers to the concentration delivered to the patient, while expired concentration is measured in exhaled gas. Their ratio provides a way to describe the relationship between the measured inspired and expired concentrations as induction proceeds. This endpoint is used to characterize the concentration pattern over time and to compare those patterns across the GE Ohmeda and Drager Apollo workstation groups. It does not, by itself, measure a clinical outcome such as a complication or recovery result.
The registry describes measurement of both concentrations using an agent monitor. It specifies measurements at 30-second intervals during the first 5 minutes and then every minute until the IV is secured. The registry does not report the actual ratios, their means or standard deviations, or a numerical between-group estimate. As a result, the endpoint's observed pattern and the precision of any comparison cannot be assessed from the registry record.
General statistical explanation: reporting means and standard deviations can describe the average value and the spread of individual observations at each time point. Repeated measurements from the same participant are related, so an analysis of change over time needs to account for that within-participant dependence. The registry names a repeated-measures method but does not give the fitted estimates or uncertainty intervals.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a study of sevoflurane concentration measurements during induction using two workstations. It identifies a continuous primary outcome, a measurement schedule, and a planned analysis approach. However, it does not report the numerical values for the primary outcome or the secondary outcomes. There is therefore no reported estimate from which to describe the direction or magnitude of the concentration-ratio patterns, or how those patterns differed between groups.
The record lists four outcome measures, including the primary ratio outcome and secondary outcomes concerning maximum inspired concentration at 1 minute, maximum sevoflurane concentrations during induction, and time to reach 90% of the maximum inspired concentration. The registry does not give the observed values for these outcomes. The record also lists zero analyses. Without outcome estimates, measures of uncertainty, or analysis output, the precision of any comparison cannot be judged.
The described two-factor repeated-measures ANOVA is intended to assess data with repeated observations and more than one factor. The Sidak test is named for multiple comparisons. The record does not specify the factors used in the model, the exact contrasts tested, or the results of any tests. No p-values, confidence intervals, or model estimates are reported in the registry record. The existence of a named method is not evidence about the results of that method.
Interpretation is also constrained by the unspecified allocation. The registry labels the arms as control and intervention but states that allocation is not stated and the arms are not a like-for-like control comparison. Without information about assignment and group characteristics, any observed group difference, if reported elsewhere, could not be interpreted as an effect attributable to workstation alone on the basis of this record. The registry does not describe adjustment for possible differences between groups.
General statistical explanation: a confidence interval communicates the range of estimates compatible with the data and the analysis assumptions. A narrow interval generally indicates greater precision than a wide interval, though neither width nor statistical significance alone establishes clinical importance. Because no confidence intervals or estimates are reported in this registry record, neither the precision nor the practical importance of a workstation contrast can be assessed.
The enrollment is listed as 24, and each adverse-event group lists 12 participants at risk. These counts do not substitute for an outcome analysis. They do not reveal whether all participants contributed measurements at every time point, whether any observations were missing, or how incomplete measurements were handled. Those details are not reported in the registry record.
Any sample-size figures accompanying the posted analysis should be read as planning illustrations based on the observed effect under stated assumptions, not as observed power or proof that the study was adequately powered. The registry record does not report its own sample-size justification. Since no observed effect estimate is reported in the record, the numerical results of any such planning exercise cannot be assessed from the registry information.
9. Statistical Methods Explained
What does a repeated-measures analysis address?
The primary outcome is measured repeatedly during induction. Observations from one participant are usually related to one another because they come from the same person. A method that treats every measurement as independent would fail to reflect that structure. General statistical explanation: repeated-measures methods account for the dependence among observations from the same participant while assessing patterns across measurement times.
The registry names a two-factor repeated-measures ANOVA. ANOVA is a general method for comparing mean outcomes across groups or conditions. In a repeated-measures setting, the model can assess whether average values vary over time and whether patterns differ across groups, depending on the factors and contrasts included. The registry does not specify the factors in detail, the model terms, or which comparisons were performed. It is therefore possible to describe the named method, but not to reconstruct the actual analysis.
What does the Sidak test do?
The registry names the Sidak test for multiple comparisons. General statistical explanation: when many comparisons are made, the chance of at least one false-positive finding can increase if each comparison is judged separately at the same threshold. A multiplicity adjustment is intended to account for this issue. The registry does not state which comparisons were included in the adjustment, how many were tested, or whether the Sidak procedure was applied to all relevant comparisons. No adjusted results or p-values are reported.
How should means and standard deviations be understood?
The record says the primary outcome will be summarized using means and standard deviations at each measurement time. A mean describes the average observed ratio, while a standard deviation describes how spread out the individual observations are around that average. General statistical explanation: these summaries can help characterize the distribution of measurements, but they do not by themselves quantify uncertainty in a group contrast. For that, readers would ordinarily need an estimate of the contrast and a measure of its uncertainty, such as a confidence interval. Such numerical outcome summaries are not reported in the registry record.
Why does the measurement schedule matter?
The primary description specifies measurements at 30-second intervals during the first 5 minutes, followed by measurements every minute until the IV is secured. Repeated measurements can provide more detail about the time course than a single measurement, but they also create analytic questions about within-participant correlation and incomplete follow-up. The registry does not state how measurements were aligned if the IV was secured at different times, how many observations each participant contributed, or how any irregular timing was handled.
The listed primary timeframe is from 0 to 10 minutes of induction. The brief summary also refers to recording during the first 10 minutes of anesthesia. The record does not explain whether all participants were measured through the full stated timeframe or how measurement duration varied, if at all. No details about the handling of measurements after induction or about data collection procedures beyond the described schedule are reported in the registry record.
What can be learned from the analysis record?
The registry lists four outcome measures and zero analyses. It names an analysis approach for the primary outcome, but it does not post the analysis results. That distinction matters: an analysis method describes how data may be evaluated; it does not provide evidence about the observed outcome. No numerical group means, standard deviations, contrasts, confidence intervals, test statistics, or p-values are reported in the registry record.
General statistical explanation: over-dispersion refers to variability greater than a statistical model expects. When present, it can make standard errors too small and conclusions appear more precise than warranted if the model does not account for it. The registry does not report an over-dispersion assessment, and the continuous primary endpoint and named ANOVA do not establish whether this issue was assessed or relevant.
General statistical explanation: missing-data methods matter when some planned measurements are unavailable. The amount and pattern of missingness can affect which observations contribute to an analysis and the assumptions behind the resulting estimates. The registry does not report missing-data counts, reasons for missingness, imputation, or a sensitivity analysis. It is not possible to determine from the record whether the repeated-measures analysis used all available observations or a more restricted set.
The registry's sample-size assumptions describe planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation; the effect to detect is expressed as a fraction of the observed effect. These are planning assumptions, not a report of the study's original design justification. General statistical explanation: a planning calculation estimates the sample size needed under specified assumptions; it is not the same as observed power, and it does not establish that a result is precise. The registry does not report its own sample-size justification.
Finally, the registry states that allocation is not stated and cautions that the arms are not a like-for-like control comparison. This limits causal interpretation independently of the statistical model. A model can adjust for specified variables, but the record does not describe such adjustment or establish that all relevant group differences were measured. No conclusion about a workstation effect can be drawn from the method description alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry names the Sidak test for multiple comparisons in the primary-outcome analysis. This indicates that multiplicity was considered in the method description, but the registry does not identify the comparison family, the number of tests, or which outcomes and time points were included. It also does not report adjusted p-values or estimates. The secondary outcomes are listed, but the record does not state whether they were part of the same multiplicity strategy or were treated separately.
Missing-data information is not reported in the registry record. The description gives a measurement schedule, but does not state how many participants had usable measurements at each time point, whether any observations were missing, why they were missing, or how missing values were handled. It also does not describe a sensitivity analysis assessing the effect of missingness. These omissions prevent assessment of whether the analyzed observations represented all enrolled participants consistently over time.
The analysis population is not reported in the registry record. The record does not specify whether analyses included all enrolled participants, only participants with measurements, or another defined group. No participant flow or analysis denominators by outcome and time point are reported. The enrollment count alone does not identify the number contributing to each analysis.
General statistical explanation: multiplicity adjustment addresses the increased chance of false-positive results when several comparisons are tested. Missing-data methods address the consequences of unavailable observations, while a clearly defined analysis population clarifies which participants contribute to each result. These issues are distinct: an adjustment for multiple comparisons does not resolve missing data, and a complete-case analysis does not by itself control multiplicity. The registry record does not give enough detail to evaluate these choices fully.
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 |
|---|---|---|---|
| Control is GE Ohmeda Workstation | 0 | 12 | 0.0% |
| Intervention is Drager Apollo Workstation | 0 | 12 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Control is GE Ohmeda Workstation | 0 of 12 |
| Intervention is Drager Apollo Workstation | 0 of 12 |
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 |
|---|---|
| Control is GE Ohmeda Workstation | 0 of 12 |
| Intervention is Drager Apollo Workstation | 0 of 12 |
The registry lists adverse-event information for the two workstation groups. In each group, 12 participants are listed as at risk for serious adverse events and 0 as affected. The same counts are listed for other adverse events, and deaths are recorded as 0 in each group. No serious adverse-event terms are listed.
These are the recorded counts in the registry. They describe what the record reports for the study groups; they do not establish that no events occurred outside the definitions, observation period, or reporting process used. The registry does not give additional detail about event collection, severity grading, causal attribution, or the duration of safety follow-up. Those details are not reported in the registry record.
General statistical explanation: a zero count is not proof that an event is impossible or that risk is absent. Its interpretation depends on the number of people observed, the duration and completeness of follow-up, and how events were sought and classified. The adverse-event figures should therefore be read as registry-reported counts, not as a broad assurance about safety or a comparison demonstrating a difference between workstations.
12. What the Result Does, and Does Not, Mean
The registry record identifies a study of concentration measurements during induction with the GE Ohmeda and Drager Apollo workstations. It specifies a continuous primary outcome, a repeated measurement schedule, and a planned analysis using two-factor repeated-measures ANOVA and the Sidak test. These details describe what the study set out to measure and how the primary outcome was intended to be analyzed.
The record does not report numerical outcome results. It therefore does not establish the observed average ratios, their variability, the pattern over time, or the size and precision of a between-group contrast. The listed secondary outcomes also lack numerical results. Without estimates and uncertainty measures, the registry record cannot support a conclusion about the direction or magnitude of the recorded differences.
The record also does not state how participants were allocated to workstations and cautions that the arms are not a like-for-like control comparison. A difference between groups, even if numerical results were available, could not automatically be attributed to workstation alone without information about assignment and relevant group characteristics. The analysis method cannot remove limitations that arise from the study design or unreported information.
General statistical explanation: statistical evidence about an average difference and evidence about a clinically important difference are not interchangeable. A precise estimate can still be too small to matter, while an imprecise estimate may leave a range of possibilities unresolved. The registry does not provide the estimates or uncertainty intervals needed for either assessment in this study.
The recorded adverse-event counts are also limited to the registry's reported figures and do not establish that risk is absent. Overall, the record is informative about the study question, measures, and named analytic approach, but it does not provide the numerical findings needed to characterize the observed concentration patterns or their uncertainty.
13. Why This Trial Matters Statistically
This trial is statistically notable because its primary outcome is measured repeatedly during induction rather than at a single time point. A sequence of measurements can describe how a continuous concentration ratio changes over time, while also requiring methods that account for the relationship among observations from the same participant. The registry's choice to name a repeated-measures ANOVA reflects that structure.
The study also compares measurements across two workstations, making both group and time patterns relevant to the stated question. The Sidak test is named for multiple comparisons, highlighting the issue of interpreting several contrasts or time points without treating each test as isolated. However, the registry does not report the exact comparisons, results, or adjustment details, so the statistical implications cannot be evaluated fully.
The record also illustrates why design information matters alongside analysis. Although the arm labels distinguish control and intervention, allocation is not stated, and the record cautions that the arms are not a like-for-like control comparison. A sophisticated repeated-measures model cannot by itself establish causal attribution when the assignment process and group comparability are not documented.
Finally, the registry distinguishes a planned analytic approach from reported evidence. It describes the primary measure and methods, but lists zero analyses and does not report numerical outcome results. This is an important boundary for readers: a methods description can clarify the intended analysis, but without estimates and uncertainty measures it cannot answer how large or precise any observed pattern was.
General statistical explanation: clear reporting of analysis populations, missing observations, estimates, and uncertainty helps readers assess both the reliability and scope of conclusions. Those details are not reported in the registry record, making the study design and outcome definitions more assessable than its statistical findings.
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 registry record has several limitations for interpreting the study. It does not report numerical results for the primary endpoint or the secondary outcomes. Means, standard deviations, group contrasts, confidence intervals, test statistics, and p-values are not reported. The direction, size, and precision of any observed differences therefore cannot be assessed from the record.
Allocation is not stated. The registry also cautions that the arms are not a like-for-like control comparison. The record does not explain how participants entered each group or provide group characteristics that would help assess comparability. Consequently, the arm labels alone should not be taken as evidence of random assignment or as a basis for causal interpretation.
Although the primary outcome description gives a measurement schedule and names a repeated-measures analysis with a Sidak test, details of the fitted model are not reported. The factors, exact contrasts, assumptions, and implementation are not specified. The record does not report the number of measurements contributing at each time point or explain how differences in measurement duration were handled.
Missing-data procedures and analysis populations are not reported in the registry record. Participant flow, outcome-specific denominators, reasons for missing observations, and sensitivity analyses are also not reported. These omissions limit assessment of whether the analyzed data could represent the enrolled group across the repeated measurement period.
The record does not report its own sample-size justification. It also does not provide enough outcome information to assess statistical precision. Finally, the registry's adverse-event counts lack further detail about event definitions, collection, or follow-up. These limitations concern what can be concluded from the registry record; they do not establish that unreported procedures or analyses did or did not occur.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Sevoflurane Concentrations in Children — NCT06510803.
- Registry record last updated 2026-02-13; status last verified 2026-02.
- Results first posted 2026-02-13.
- 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
NCT06510803, “Sevoflurane Concentrations in Children,” is marked completed and lists an enrollment of 24. The study compares sevoflurane wash-in during induction using the GE Ohmeda and Drager Apollo workstations. Its primary outcome is the ratio of inspired to expired sevoflurane concentrations over the first 10 minutes of induction, with repeated measurements described during that period.
The registry names a two-factor repeated-measures ANOVA and Sidak testing for multiple comparisons. It lists four outcome measures and zero analyses, but does not report numerical outcome results. Allocation is not stated, and the record cautions that the arms are not a like-for-like control comparison. Serious adverse events, other adverse events, and deaths are recorded as 0 in each group. Additional details about missing data, analysis populations, and the study's sample-size justification are not reported in the registry record.