General Anesthesia With ETT vs LMA in Patients Undergoing Ablation for Atrial Fibrillation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for General Anesthesia With ETT vs LMA in Patients Undergoing Ablation for Atrial Fibrillation (NCT02896595), a randomized na study. The primary outcome is Procedure Time (Minutes).

2. Clinical Question

The comparison concerns two airway approaches used during general anesthesia; it is not a comparison of general anesthesia with sedation. The registry description gives background reasons for considering different airway approaches, including procedure and recovery time, airway complications, and effects on anesthetic requirements. Those considerations do not themselves establish what happened in this trial. The posted primary outcome is procedure time, and the recorded group summaries address that outcome directly.

The registry describes a randomized comparison with 100 participants enrolled. The primary outcome summaries include 50 participants in each group. Results therefore describe the recorded comparison among those groups, but further details about participant characteristics, eligibility, and analysis populations are not reported in the registry record.

3. Trial Design

This was a randomized, double-masked, parallel-group trial with an enrollment of 100. Participants were assigned to general anesthesia with an endotracheal tube or general anesthesia with a laryngeal mask airway. The registry record lists Virginia Commonwealth University as the sponsor and identifies atrial fibrillation as the condition under study. The record marks the study as completed.

The study began in 2016-09, and primary completion is recorded as 2018-12-11. The phase is listed as not applicable. Outcome summaries for the primary comparison include 50 participants in each group. The registry record does not describe the randomization sequence, allocation concealment, or which people were masked. It also does not report the procedures used to maintain masking or whether masking was assessed.

The primary outcome was procedure time, measured from procedure start to procedure end in minutes, with a timeframe of up to 270 minutes. The registry lists 21 secondary outcomes, including fluoroscopy time, total anesthesia time, intra-procedure opioids, anesthetic requirements, intraoperative hemodynamics, and time to discharge from the post-anesthesia care unit. Numerical result summaries are posted for three secondary outcomes: fluoroscopy time, total anesthesia time, and total intra-procedure opioids.

Although the official title calls the trial non-inferiority, the registry record does not report the non-inferiority margin, its justification, or a formal analysis against that margin. The original sample-size justification and planned analysis methods are also not reported in the registry record. The posted results should therefore be read as group summaries and comparisons, rather than as documentation of a fully specified non-inferiority analysis.

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

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.

6. Primary Endpoint

The registry lists the primary outcome as Procedure Time (Minutes), measured over Up to 270 minutes.

The primary endpoint was procedure time in minutes. It was defined as the interval from the start of the procedure to its end, as recorded in minutes, with a stated timeframe of up to 270 minutes. The outcome was summarized as a mean and standard deviation for each randomized group.

Procedure time is a continuous measure of how long the catheter ablation procedure lasted. As a general statistical explanation, a continuous endpoint can retain differences in magnitude across participants rather than reducing each observation to a category such as shorter or longer than a threshold. A mean gives the group’s average recorded time, while the standard deviation describes variation among individual observations around that mean.

This endpoint is relevant to a comparison of airway approaches because the study background discusses procedure time among the considerations for airway management during general anesthesia. However, procedure time captures only one aspect of the procedure. It is not a direct measure of recovery, patient satisfaction, airway complications, or clinical outcomes after ablation. Those topics cannot be inferred from the primary endpoint alone.

The registry reports a mean procedure time of 128.7 minutes for the ETT group and 137.8 minutes for the LMA group. The posted mean difference, defined as LMA minus ETT, is 9.1 minutes. The confidence interval and p-value describe the statistical uncertainty and evidence associated with this comparison; they do not supply the missing non-inferiority margin or establish the clinical importance of a particular difference.

7. Results Posted in the Registry

• General Anesthesia With Laryngeal Mask Airway: mean 137.80 versus 128.70 on control; difference 9.10 (95% CI 7.05 to 11.15), standardized effect d = 1.74; z-test p = <0.001.

8. Secondary Efficacy Endpoints

The registry also posts results for secondary outcomes. For each outcome below, the endpoint type, the test applied to the posted summary statistics, the result and its interpretation are given in turn. Secondary endpoints are usually not adjusted for multiple testing, so they support rather than confirm the primary finding.

Fluoroscopy Time

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • General Anesthesia With Laryngeal Mask Airway: mean 28.70 versus 27.10 on control; difference 1.60 (95% CI -3.40 to 6.60), standardized effect d = 0.13; z-test p = 0.530.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia With Laryngeal Mask Airway and the control. The interval gives the range of effects that remain compatible with the data.

Total Anesthesia Time

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • General Anesthesia With Laryngeal Mask Airway: mean 184.70 versus 179.00 on control; difference 5.70 (95% CI -9.94 to 21.34), standardized effect d = 0.14; z-test p = 0.475.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia With Laryngeal Mask Airway and the control. The interval gives the range of effects that remain compatible with the data.

Total Intra-procedure Opioids

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard errors.
• Result:
  • General Anesthesia With Laryngeal Mask Airway: mean 109.20 versus 111.70 on control; difference -2.50 (95% CI -19.52 to 14.52), standardized effect d = -0.06; z-test p = 0.773.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between General Anesthesia With Laryngeal Mask Airway and the control. The interval gives the range of effects that remain compatible with the data.

The three secondary outcomes with numerical results show a less distinct pattern than the primary endpoint. The posted mean differences point in different directions, and each secondary confidence interval includes zero. Their unadjusted p-values do not provide strong evidence of a difference under conventional thresholds. These results are best read as descriptive estimates with substantial uncertainty rather than as a consistent secondary confirmation of the primary result.

The secondary measures address related but distinct aspects of the procedure and anesthesia: fluoroscopy time, total anesthesia time, and intra-procedure opioids. They are not interchangeable with procedure time. A difference in one measure does not establish a corresponding difference in another, and the primary result should not be used to fill gaps in the secondary evidence. Likewise, the secondary estimates do not explain why the primary means differed.

The registry lists 21 secondary outcomes, while numerical comparisons are available for three. Numerical results for the other secondary outcomes are not reported in the registry record. The record does not explain why numerical summaries are absent or whether those outcomes were assessed but not posted. Therefore, the visible secondary pattern is incomplete with respect to the full set of listed outcomes.

Unadjusted secondary results carry less weight because multiple outcomes can create more opportunities for chance findings when each is examined separately. The registry record does not report a multiplicity adjustment, a testing hierarchy, or which secondary outcomes were designated as key confirmatory outcomes. This does not invalidate the posted estimates, but it means they should be treated as exploratory or descriptive rather than as independent proof of a coherent treatment effect across outcomes.

Secondary outcomes registered for this trial, for reference (only those above were recalculated):

• Fluoroscopy Time
• Total Anesthesia Time
• Time to Discharge From PACU
• Total Intra-procedure Opioids
• Anesthetic Requirements
• Anesthetic Requirements
• Intraoperative Hemodynamics
• Intraoperative Hemodynamics

9. Statistical Interpretation

10. Statistical Methods Explained

What does the mean difference represent?

The primary outcome is continuous, and the registry summarizes it using group means. The ETT mean is 128.7 minutes and the LMA mean is 137.8 minutes. The comparison is oriented as LMA minus ETT, yielding a mean difference of 9.1 minutes. A positive value in this direction means the recorded mean is higher for LMA than for ETT. This is a comparison of group averages; it does not mean every participant in one group had a longer procedure than every participant in the other.

As a general statistical explanation, a mean difference expresses a comparison in the original units of the outcome. Here the units are minutes, so the estimate can be read on the same scale as procedure time. The estimated difference does not show how individual values were distributed, whether there were outliers, or whether the group distributions had similar shapes. The registry supplies a standard deviation for each primary group, but detailed individual-level data and distribution plots are not reported in the registry record.

What do standard deviation and standard error describe?

The primary group summaries use standard deviations: 4.2 minutes for ETT and 6.1 minutes for LMA. As a general statistical explanation, a standard deviation describes the spread of individual observations around a group mean. It is not the uncertainty of the mean itself. A mean can be estimated more precisely when there is less variability or more observations, but the registry’s group standard deviations alone do not describe every feature of the observed data.

The posted secondary summaries use standard errors rather than standard deviations. In general, a standard error describes uncertainty in an estimated quantity, such as a mean, rather than the spread of individual observations. The distinction is important when reading the secondary results: their reported spread values should not be interpreted as the range or typical participant-to-participant variation. The registry record does not provide standard deviations for those secondary outcomes.

How should the confidence interval be read?

The primary confidence interval for the mean difference extends from 7.047 to 11.15 minutes. In general, a confidence interval gives a range of values compatible with the estimate under the statistical method used and its assumptions. An interval that does not include zero is consistent with a nonzero difference under a conventional two-sided comparison. It does not tell the reader the probability that a particular value is true, and it does not establish clinical importance. The confidence level and the method used to construct the interval are not reported in the registry record.

The secondary intervals are wider relative to their estimates and each includes zero. As a general explanation, including zero means the interval does not rule out no mean difference at the corresponding confidence level. It also includes values in both directions in these secondary comparisons. The registry does not report the confidence level, the interval-construction method, or any adjustment for the number of outcomes examined.

What does the p-value say?

The primary unadjusted p-value is <0.001. As a general statistical explanation, a p-value measures how incompatible the observed data, or data more extreme, are with a specified null model under the assumptions of the test. It is not the probability that the null hypothesis is true, nor a measure of the size or importance of an effect. The statistical test and its assumptions are not reported in the registry record, so the p-value should be treated as the posted unadjusted result rather than as evidence of a particular named test.

The secondary p-values are unadjusted. In general, when many outcomes are examined, the chance of obtaining one or more apparently unusual results can increase if each is judged separately without accounting for multiplicity. The record lists 21 secondary outcomes, but does not report a multiplicity adjustment or a hierarchy of secondary hypotheses. The secondary p-values therefore warrant more cautious interpretation than a single prespecified primary comparison.

What does randomization contribute?

Random assignment is intended, in general, to make treatment groups comparable on average with respect to measured and unmeasured baseline characteristics. It does not ensure that every characteristic is balanced in a particular trial. The registry identifies the allocation as randomized but does not report sequence generation, allocation concealment, baseline characteristics, or an adjusted analysis. The group summaries are consequently useful for describing the randomized comparison, while the available record does not permit a detailed assessment of balance or the implementation of randomization.

The study is also labeled double-masked. In general, masking can reduce the influence of expectations on care or outcome assessment, depending on who is masked and what procedures are used. The registry does not identify the masked parties or describe how masking was maintained. Because the airway devices differ, the record’s masking label alone does not establish how masking worked in practice.

What analysis details are unavailable?

The registry record does not report the statistical model, the hypothesis test used for the primary endpoint, a prespecified analysis plan, missing-data methods, or the analysis population. It also does not report interim analyses. These details matter for judging whether the posted estimates correspond to the planned analysis and how robust the conclusions are to assumptions or incomplete outcome data. The absence of these details in the registry record is not evidence that a particular method was or was not used; it means the method is not documented in the record.

11. Confidence Intervals and Precision

The primary estimate is a mean difference of 9.1 minutes for LMA minus ETT, with a confidence interval from 7.047 to 11.15 minutes. The interval does not include zero, and its endpoints are both positive. Thus, the posted interval places the estimated difference on the side of longer mean procedure time for LMA. The interval also gives a range of values compatible with the data and the interval method, rather than a single exact effect.

Precision is reflected partly in the width of an interval: narrower intervals generally indicate less statistical uncertainty than wider ones, assuming comparable methods and scales. The primary interval is reported to three decimal places at its endpoints, but numerical detail should not be mistaken for certainty about the true difference. The confidence level and construction method are not reported in the registry record, which limits a fuller evaluation of the interval.

The secondary intervals include zero: fluoroscopy time ranges from -3.397 to 6.597 minutes; total anesthesia time ranges from -9.943 to 21.34 minutes; and total intra-procedure opioids ranges from -19.52 to 14.52 mcg. These intervals include both negative and positive differences, so the posted estimates for those outcomes are less definitive about direction. Their interpretation also depends on the uncertainty reflected in the interval, not only on the point estimate or p-value.

A confidence interval does not resolve whether an effect matters clinically. The registry does not report a threshold for an important difference in procedure time, and it does not report the non-inferiority margin named in the official title. Precision around a difference from zero and precision relative to a clinically chosen boundary are distinct questions. The posted results support describing the estimated difference and its interval, but not an unreported clinical threshold or formal non-inferiority conclusion.

12. Planning a Similar Trial: Sample Size

This is a planning illustration, not a re-evaluation of the original trial. It asks: if a new study wanted to detect a difference like the one observed, or a smaller one, how large would it need to be? It is deliberately not “observed power” of the finished trial, which is not a meaningful quantity.

The planning figures are expressed as participants per arm, not as a total across both arms or as total events. They use the observed effect as a starting point and show hypothetical planning scenarios for detecting the stated fraction of that effect. For example, the rows labeled 100%, 75%, and 50% of the observed effect represent progressively smaller target effects relative to the estimate in the trial.

The stated planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The effect to detect is the stated fraction of the observed effect. Under these assumptions, the 80% power column gives the number of participants per arm associated with an 80% chance of detecting the specified effect if that effect is real and the assumptions hold. The 90% power column describes the corresponding planning target for a 90% chance. These are design probabilities, not probabilities that the observed result is correct.

Smaller effects generally require more participants to distinguish them from random variation at a given significance level and power target. That pattern is reflected in the planning figures: scenarios targeting a smaller fraction of the observed effect call for larger group sizes. The figures are planning illustrations based on the observed effect, not observed power.

The registry record does not report the original trial’s sample-size justification or design assumptions. The planning assumptions listed for these illustrations should not be mistaken for the assumptions used when the study was designed. The figures also do not establish that a future trial would reproduce the observed effect; they show how sample-size requirements change under the stated hypothetical assumptions.

13. How the Sample Size Is Derived

Power is the probability that a study of a given size rejects the null hypothesis when a specific true effect exists. It depends on four things: the effect to detect, the variability of the outcome, the significance level (here a two-sided α of 0.05, so z_1−α/2 = 1.960) and the desired power (z_1−β = 0.842 for 80% and 1.282 for 90%).

Formula

n is the number of participants in each arm, Δ is the difference in means to detect and σ is the common standard deviation.

Worked calculation for this trial

1. Observed difference Δ = 9.100; pooled standard deviation σ = 5.237.
2. n = 2 × (1.96 + 0.842)² × 5.237² / 9.100² = 5.2, rounded up to 6 participants per arm for 80% power.

The smaller-effect rows in the table above repeat the same calculation with the effect multiplied by 0.75 and 0.5 (for ratios, applied to the logarithm of the ratio).

R code

alpha <- 0.05
z_a   <- qnorm(1 - alpha / 2)          # two-sided
delta <- 9.10000000000002                      # observed difference in means
sigma <- 5.23688838911046                     # pooled standard deviation
n_per_arm <- function(power, frac = 1) {
  ceiling(round(2 * (z_a + qnorm(power))^2 * sigma^2 / (delta * frac)^2, 6))
}
for (f in c(1, 0.75, 0.5))
  cat(sprintf("%3.0f%% of observed effect: n per arm = %s (80%% power), %s (90%% power)\n", 100 * f,
              format(n_per_arm(0.80, f), big.mark = ","), format(n_per_arm(0.90, f), big.mark = ",")))

# Check against R's built-in function (t-based, so very slightly larger)
cat("power.t.test:", round(power.t.test(delta = delta, sd = sigma, power = 0.80)$n, 1), "\n")

# Simulation: exact two-sample t-test using simulated means and variances
set.seed(2896595)
n    <- n_per_arm(0.80)
reps <- 20000
m_diff <- rnorm(reps, delta, sigma * sqrt(2 / n))             # difference in sample means
s2     <- sigma^2 * rchisq(reps, 2 * (n - 1)) / (2 * (n - 1))   # pooled sample variance
tstat  <- m_diff / sqrt(s2 * 2 / n)
cat(sprintf("Simulated power at n = %s per arm: %.3f (%d replicates)\n", format(n, big.mark = ","), mean(abs(tstat) > qt(0.975, 2 * (n - 1))), reps))

Output from running the code

100% of observed effect: n per arm = 6 (80% power), 7 (90% power)
 75% of observed effect: n per arm = 10 (80% power), 13 (90% power)
 50% of observed effect: n per arm = 21 (80% power), 28 (90% power)
power.t.test: 6.3 
Simulated power at n = 6 per arm: 0.779 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry record lists 21 secondary outcomes in addition to the primary endpoint. It does not report whether the study used a prespecified hierarchy for testing those outcomes, whether any outcomes were designated as confirmatory, or whether p-values or confidence intervals were adjusted for multiple comparisons. The numerical secondary p-values are identified as unadjusted. When several outcomes are tested, unadjusted results should be interpreted with caution because the chance of at least one unusual result can rise across a collection of tests.

The official title identifies the study as a non-inferiority trial, but the non-inferiority margin is not reported in the registry record. The record also does not report how that margin was chosen, what analysis population was intended for the non-inferiority question, or the decision rule for drawing a non-inferiority conclusion. Those omissions prevent assessment of the trial as a formal non-inferiority analysis from the posted results alone.

Missing-data methods are not reported in the registry record. The primary outcome summaries show 50 participants in each group, but the record does not explain whether all randomized participants contributed primary outcome data, whether any data were missing, or how incomplete observations were handled. It also does not identify an intention-to-treat, modified intention-to-treat, or per-protocol analysis population. These details are especially relevant when interpreting a non-inferiority question, because analysis populations and missing observations can affect conclusions.

The record does not report a prespecified statistical analysis plan, model details, interim analyses, or sensitivity analyses. This absence should be understood as missing documentation in the registry record, not as evidence that these procedures were not conducted. Without the details, readers cannot compare the posted analyses with a planned approach or evaluate the robustness of the result to alternative assumptions.

15. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports 50 participants at risk in each group for serious adverse events, other adverse events, and deaths. It records zero serious adverse events, zero other adverse events, and zero deaths in both the ETT and LMA groups. No serious adverse event terms are listed.

These figures describe the events recorded in the registry. They do not establish that no event of any kind occurred outside the recorded categories or reporting period. The safety observation window, event definitions, collection methods, and any relationship assessment are not reported in the registry record. The record also does not provide event-level descriptions beyond the zero counts.

As a general statistical point, zero recorded events in a group does not prove that the underlying risk is zero. The amount of information about uncommon events depends on the number of participants observed and the duration and completeness of follow-up. The registry does not report a safety comparison model or confidence intervals for event rates, so the counts should be read descriptively rather than as a precise estimate of comparative safety.

16. What the Result Does, and Does Not, Mean

The posted primary result shows a mean procedure time of 128.7 minutes with ETT and 137.8 minutes with LMA. The mean difference, expressed as LMA minus ETT, is 9.1 minutes, with a confidence interval from 7.047 to 11.15 minutes and an unadjusted p-value of <0.001. The interval is entirely positive, so the posted primary comparison is consistent with longer mean procedure time in the LMA group.

That result does not, on its own, establish whether the observed difference is important in clinical practice. The registry record does not state a clinically meaningful threshold for procedure time. It also does not report the non-inferiority margin required to interpret the study’s title as a formal non-inferiority question. A difference from zero and a conclusion that one approach is non-inferior are different statistical claims.

The results do not establish effects on outcomes that are not numerically reported, including the other listed secondary endpoints. They also do not establish differences in recovery, airway complications, patient satisfaction, or later clinical outcomes. The trial background discusses some of these issues, but background rationale is not a result. The safety counts report no recorded adverse events or deaths in either group; those counts do not show that risks are absent.

The randomized design supports a comparison between the assigned groups, but details needed to assess the analysis are not reported, including missing-data handling, analysis population, and the statistical model. The enrollment of 100 and the group summaries of 50 each provide the scale of the comparison, while the confidence interval conveys uncertainty around the primary estimate. The findings should be interpreted as the posted trial results, with conclusions limited to the outcomes and analysis details documented in the registry record.

17. Why This Trial Matters Statistically

This trial illustrates why a stated study objective and the statistical evidence needed to evaluate it are not always the same thing. The official title describes a non-inferiority trial, but the registry record does not report the non-inferiority margin or a formal analysis against that margin. The posted primary estimate and its interval describe a difference in mean procedure time; they do not substitute for the missing non-inferiority specification.

It also illustrates the value of reading an estimate together with its uncertainty. The primary group means and mean difference give the direction and scale of the observed comparison, while the confidence interval indicates a range of compatible differences. A p-value alone would not convey the size of the difference or its precision. Conversely, a confidence interval alone does not establish clinical importance without a relevant threshold.

The secondary outcomes show why results across multiple measures require context. The registry lists 21 secondary outcomes, but numerical comparisons are posted for three, and the reported secondary results are unadjusted. Without a reported multiplicity plan, isolated secondary findings should not be treated as independent confirmation. Clear reporting of the outcome hierarchy, analysis methods, and missing-data approach would help readers distinguish confirmatory results from exploratory ones.

Finally, the study is a useful example of how registry records can document group summaries while leaving important design and analysis details unavailable. Randomization, masking, and the primary outcome are identified, but the implementation of masking, original sample-size justification, analysis populations, and statistical methods are not. Recognizing that boundary helps keep interpretation tied to the evidence that is actually documented.

18. 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 leaves several trial-specific details unavailable. It does not provide full eligibility criteria, participant characteristics, baseline summaries, or the number of participants with complete primary outcome data. Although the primary summaries include 50 participants per group, the record does not state how missing observations were handled or identify the analysis population. These gaps limit assessment of representativeness, group balance, and the relation between enrollment and analyzed data.

The official title calls the study non-inferiority, but the margin, its clinical justification, and the formal decision rule are not reported. Without those details, the primary mean difference cannot establish non-inferiority. The original sample-size justification and planned analysis methods are also not reported, so the planning illustrations should not be taken as the trial’s own design rationale.

The record identifies double masking but does not say who was masked or how masking was maintained. It does not report allocation concealment, the randomization procedure, or whether any adjusted analysis was conducted. The statistical test and confidence-interval method are not described. These omissions constrain assessment of potential bias and the assumptions behind the reported inferential statistics.

Numerical results are available for only three of the 21 listed secondary outcomes, and the posted secondary p-values are unadjusted. The registry does not describe a multiplicity plan or explain the absence of numerical results for the remaining secondary outcomes. Safety information is also limited to event counts; definitions and the observation window are not reported. These limitations do not negate the posted results, but they narrow the conclusions that can be drawn from the registry record.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: General Anesthesia With ETT vs LMA in Patients Undergoing Ablation for Atrial Fibrillation — NCT02896595.
• Registry record last updated 2020-01-21; status last verified 2020-01.
• Results first posted 2020-01-21.
• 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.

22. Record Summary

NCT02896595 is a completed randomized, double-masked, parallel-group trial sponsored by Virginia Commonwealth University. It enrolled 100 participants undergoing catheter ablation for atrial fibrillation, comparing general anesthesia with an endotracheal tube against general anesthesia with a laryngeal mask airway. The primary outcome was procedure time in minutes.

The posted group means were 128.7 minutes for ETT and 137.8 minutes for LMA. The mean difference for LMA minus ETT was 9.1 minutes, with a confidence interval from 7.047 to 11.15 minutes and an unadjusted p-value of <0.001. Numerical summaries are also posted for three secondary outcomes. The registry reports zero serious adverse events, zero other adverse events, and zero deaths in each group.

The official title describes a non-inferiority trial, but the non-inferiority margin and formal analysis are not reported in the registry record. Details of the analysis population, missing-data handling, and statistical methods are also not reported.