Oral Versus Intravenous Sedation for Ocular Procedures: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Oral Versus Intravenous Sedation for Ocular Procedures (NCT03246724), a randomized phase 4 study. The primary outcome is Patient Satisfaction.

2. Clinical Question

The registry describes a comparison of sedation routes and states a hypothesis of no difference in patient satisfaction. Its primary endpoint is a mean score derived from a 12-question survey, with responses graded from 1 to 6 and higher mean scores indicating greater satisfaction. The central clinical question is therefore whether satisfaction scores under the oral route meet the study’s intended comparison with the intravenous route.

However, the posted outcome results list means for cataract, retina, cornea, and glaucoma procedure categories. The recalculated comparisons also contrast these procedure categories with the cataract category; they do not provide an oral-versus-intravenous treatment contrast. The registry’s reported ANCOVA analysis includes the procedure categories and gives a non-inferiority p-value of <0.05, but does not report the treatment-effect estimate, confidence interval, or enough detail to interpret its direction and magnitude. The distinction between the study’s clinical question and the results’ displayed grouping is important when reading the findings.

3. Trial Design

The registry describes a completed, single-center, randomized, double-blind, double-dummy, parallel-group study. It is listed as phase 4 and was sponsored by Boston Medical Center. The record gives enrollment as 327 and dates the study start to 2017-10-16, with primary completion on 2019-11-30. Its stated purpose was to evaluate patient satisfaction after eye surgery when patients received a capsule compared with an intravenous dose of sedation.

According to the study summary, each participant received a capsule and an IV before the procedure, without knowing which one administered the sedative. The procedure was the one already planned with the patient’s doctor. The study description says doctors completed satisfaction surveys after the procedure and participants completed a survey at a regularly scheduled visit the day after surgery. The primary endpoint timeframe is separately described as administration up to two days after surgery.

The record’s arm descriptions identify cataract, retina, cornea, and glaucoma procedure categories. It lists triazolam and midazolam, as well as microcrystalline cellulose and sodium chloride 0.9%, among the interventions. The exact assignment of those substances to treatment routes and the dosing details are not reported in the registry record. Nor does the record explain how randomization was implemented or how masking was maintained beyond its design labels.

Although the study is framed as a route comparison, the posted outcome summaries are grouped by procedure category. The sponsor’s reported analysis is described as ANCOVA across those categories and labelled non-inferiority. The registry record does not report an analysis estimate, a confidence interval, the non-inferiority margin, or the covariates used. The planned sample-size rationale and the trial’s original statistical design assumptions 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.

Before assignment: Out of 327 patients enrolled, 283 completed study participation and 44 patients did not complete study participation as they were dropped or withdrew from the study. 22 patients were dropped before randomization and 22 patients discontinued from study after randomization due to reasons seen in the participant flow table.

Overall Study

Reasons for not completing this period:

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: The data displays information for participants that complete study participation.

6. Primary Endpoint

The registry lists the primary outcome as Patient Satisfaction, measured over The patient satisfaction survey was administered up to two days after surgery..

The primary endpoint is patient satisfaction, represented by a mean score on a scale. The registry describes a 12-question survey. Each response is graded from 1 to 6, where 1 is least satisfied and 6 is most satisfied; the responses are averaged to create an overall score for each patient. Higher mean scores correspond to higher reported satisfaction. The survey was administered up to two days after surgery.

A mean is a way to describe the average score across the observations in a group. The standard deviation reported with each mean describes how dispersed individual scores are around that average. These summaries help characterize both the typical reported satisfaction and the variability in scores, but they do not show the distribution of every patient’s responses or explain why a score was given.

Satisfaction is relevant to the study’s stated comparison because the registry asks whether the route of sedation is associated with a difference in patients’ experience of the procedure. It is a patient-reported outcome, not a direct measure of sedation depth, procedural success, or safety. The endpoint can inform the specific question about reported satisfaction, but should not be treated as a substitute for other clinical outcomes.

The registry record does not report the survey’s validation, handling of incomplete answers, or prespecified threshold for a meaningful difference. While it describes a non-inferiority analysis, the margin and endpoint estimate are not reported in the registry record. Without those details, the posted summaries do not establish how the sponsor defined an acceptable difference in satisfaction.

7. Results Posted in the Registry

• Retina Procedures: mean 5.23 versus 5.37 on control; difference -0.14 (95% CI -0.34 to 0.06), standardized effect d = -0.22; z-test p = 0.161.
• Cornea Procedures: mean 5.37 versus 5.37 on control; difference 0.00 (95% CI -0.20 to 0.20), standardized effect d = 0.00; z-test p = 1.000.
• Glaucoma Procedures: mean 5.05 versus 5.37 on control; difference -0.32 (95% CI -0.60 to -0.04), standardized effect d = -0.47; z-test p = 0.027.

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.

Surgeon Satisfaction

• 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 deviations.
• Result:
  • Retina Procedures: mean 5.57 versus 5.28 on control; difference 0.29 (95% CI 0.02 to 0.56), standardized effect d = 0.32; z-test p = 0.038.
  • Cornea Procedures: mean 5.34 versus 5.28 on control; difference 0.06 (95% CI -0.24 to 0.36), standardized effect d = 0.06; z-test p = 0.698.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Retina Procedures than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Cornea Procedures and the control. The interval gives the range of effects that remain compatible with the data.

Anesthesiologist/Certified Registered Nurse Anesthetist (CRNA) Satisfaction

• 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 deviations.
• Result:
  • Retina Procedures: mean 5.14 versus 5.16 on control; difference -0.02 (95% CI -0.31 to 0.27), standardized effect d = -0.02; z-test p = 0.891.
  • Cornea Procedures: mean 5.33 versus 5.16 on control; difference 0.17 (95% CI -0.11 to 0.45), standardized effect d = 0.19; z-test p = 0.232.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Retina Procedures and the control. The interval gives the range of effects that remain compatible with the data.
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Cornea Procedures and the control. The interval gives the range of effects that remain compatible with the data.

The registry posts surgeon satisfaction and anesthesiologist/CRNA satisfaction as secondary endpoints, each measured by a mean score with a standard deviation. Their summaries are also organized by the four procedure categories. Across these endpoints, the category patterns are not uniform: the relative ordering and size of the observed category differences vary by endpoint. This variability is a reason to treat the secondary results as supporting context rather than as a single consistent confirmation of the primary result.

The secondary measures describe satisfaction reported by clinicians involved in the procedure, while the primary endpoint describes patient satisfaction. They address related but distinct perspectives. A pattern in clinician ratings cannot by itself establish what patients experienced, and a patient satisfaction result does not determine clinician satisfaction. The registry’s reported ANCOVA results for the secondary endpoints are also labelled non-inferiority and give p <0.05, but the estimates and confidence intervals are not reported in the registry record.

The recalculated secondary contrasts are unadjusted comparisons of procedure categories against cataract procedures. They are not route-specific estimates and should not be treated as evidence about oral versus intravenous sedation. Their p-values are unadjusted, and several outcomes and contrasts are reported. When many comparisons are considered, some results may appear notable by chance even when no corresponding effect is present. The registry record does not report a multiplicity adjustment or a hierarchy for interpreting the secondary endpoints.

Accordingly, secondary findings carry less weight than a fully specified primary treatment analysis. They can describe how satisfaction ratings vary across the posted categories, but they do not resolve the missing route-specific primary estimate or establish a consistent route effect across patient and clinician perspectives. The registry record does not report enough detail to determine whether the secondary analyses were prespecified in the same form as presented or how they were intended to influence the overall conclusion.

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

• Surgeon Satisfaction
• Anesthesiologist/Certified Registered Nurse Anesthetist (CRNA) Satisfaction

9. Statistical Interpretation

10. Statistical Methods Explained

Statistical methods answer different questions. A descriptive mean characterizes the average observed score in a group; a standard deviation characterizes variation among scores. A contrast between means describes how the averages differ between two groups. A confidence interval expresses the uncertainty around that contrast under the assumptions of the calculation. A p-value describes how compatible the observed data are with a specified null hypothesis under a statistical model; it is not a measure of effect size or the probability that a conclusion is true.

What does the sponsor’s ANCOVA label mean?

ANCOVA, or analysis of covariance, is a method for comparing outcome means while accounting for selected covariates. In general, adjustment can help address differences in measured characteristics included in the model. The registry record identifies ANCOVA as the sponsor’s analysis method, but does not report the covariates, model specification, adjusted estimate, standard error, or confidence interval. The record also does not explain whether and how the analysis accounts for the study’s procedure categories when estimating the route comparison. As a result, the method label alone is not enough to reconstruct or fully assess the analysis.

The reported result is labelled non-inferiority and has p <0.05. A non-inferiority analysis ordinarily evaluates whether an intervention is not worse than a comparator by more than a prespecified margin. The margin is essential to interpreting that conclusion. The registry record does not report the margin, the estimate relative to it, or the confidence interval used for the sponsor’s conclusion. The p-value therefore cannot, on its own, show the size of any difference or how close the result was to a non-inferiority boundary.

What do the recalculated contrasts represent?

The recalculated contrasts are simple, unadjusted comparisons derived from the posted group means, standard deviations, and group sizes. The reference is the cataract-procedure category, and the other contrasts compare retina, cornea, or glaucoma procedure categories with it. They do not adjust for covariates and do not estimate the oral-versus-intravenous contrast. This difference in question and method matters: the recalculations can describe the posted category summaries, but they cannot substitute for the sponsor’s adjusted route comparison.

The mean difference is expressed in survey-score points. A negative value means the second named category’s mean is lower than the cataract category’s mean; a positive value means it is higher. The estimate should be considered alongside its confidence interval, which indicates the precision of that unadjusted contrast. An interval spanning zero is compatible with a range of contrasts that includes no difference under the calculation assumptions. An interval that does not span zero indicates that zero is outside that interval, but it does not turn a comparison of procedure categories into a treatment-route result.

The unadjusted p-values reported with these recalculations do not account for multiple comparisons. They also do not incorporate the sponsor’s ANCOVA model. A p-value below a conventional threshold is not by itself proof of a clinically important difference, while a larger p-value does not establish equivalence. These interpretive cautions are especially relevant when the contrasts are not the primary treatment comparison in the clinical question.

Why can dispersion matter?

Standard deviations describe how widely individual satisfaction scores vary around each group mean. When scores are more variable, an average can be a less precise description of the individual experiences within that group. In general, variability and the amount of information available both affect the uncertainty of a mean difference. Procedure categories also have different reported group sizes, so the precision of their estimates need not be the same.

The calculations use continuous-outcome summaries and do not show individual-level data. Without those data, it is not possible to examine score distributions, identify outliers, assess whether the score scale behaves similarly across categories, or adjust for participant characteristics. The registry record does not report the analysis population, missing-score handling, or whether the sponsor’s model used all randomized participants or a subset.

How should the reported p-value be read?

For the sponsor analysis, p <0.05 is the reported result for the analysis labelled non-inferiority. It indicates that the sponsor’s analysis met its stated p-value criterion, but the record does not provide the additional information needed to determine the analysis’s exact estimand, effect direction, or precision. A p-value does not communicate how large an effect is, nor does it establish that two treatments are identical. In non-inferiority work, the margin and confidence interval are central to understanding what the data support.

For the recalculated comparisons, the posted p-values are unadjusted and refer to procedure-category contrasts. They are best interpreted as descriptive statistical tests tied to those specific contrasts. The record’s discrepancy flag indicates that these recalculations and the sponsor’s analysis do not align. The sponsor’s own analysis takes precedence for the intended treatment comparison, while the unadjusted calculations should remain secondary context rather than a competing conclusion.

11. Confidence Intervals and Precision

Precision concerns how narrowly an effect is estimated. The recalculated confidence intervals quantify uncertainty around the unadjusted differences between procedure categories and the cataract category. They are not confidence intervals for the oral-versus-intravenous comparison. The interval for the retina contrast is -0.336 to 0.056, and the interval for the cornea contrast is -0.200 to 0.200. Both include zero. The interval for the glaucoma contrast is -0.604 to -0.036 and does not include zero. Each interval should be interpreted only for the category contrast it describes.

Interval width reflects both the variability in scores and the information available for a contrast. In general, greater uncertainty produces a wider interval. The group standard deviations and sizes differ across categories, so their estimates have different precision. The registry record does not report confidence intervals for the sponsor’s ANCOVA result, making it impossible to assess the precision of the primary route comparison from that analysis.

A confidence interval is not a range that contains a fixed proportion of individual patient scores, and it does not measure clinical importance. The score scale runs from 1 to 6, but the record does not report a threshold for a meaningful difference. Even a category contrast with an interval excluding zero does not establish an important difference between sedation routes, because the categories are not the treatment routes.

For non-inferiority interpretation, the sponsor’s confidence interval and prespecified margin would be important to judge whether the plausible values rule out an unacceptable loss. Neither is reported in the registry record. Thus, the sponsor’s p-value cannot show how precisely non-inferiority was established. The recalculated intervals offer precision information only for the stated, unadjusted category comparisons.

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 sample-size figures are planning illustrations based on observed effects, not the trial’s own design calculation. For these continuous outcomes, the figures are participants per arm. They are not total event counts. The listed 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. The registry record’s original sample-size assumptions and justification are not reported.

The 80% power column gives the illustrative number of participants per arm under which a planned study would have an 80% chance of detecting the specified effect, assuming the listed calculation assumptions hold. The 90% power column describes the corresponding planning target for a 90% chance. Power is a design property tied to an assumed effect and analysis; it does not state the probability that the trial result is correct.

Rows for 100% of the observed effect use the full recalculated effect as the planning target. Rows for 75% and 50% of the observed effect use progressively smaller target effects. Smaller effects are harder to distinguish from random variation, so they require more participants per arm under the same assumptions. Where an observed contrast is near zero, an illustration based on detecting a fraction of that contrast can produce very large planning figures; such figures should not be taken as a proposed design for the trial’s route comparison.

These values are not observed power. They are hypothetical planning illustrations derived from observed summary statistics and do not repair the missing treatment-specific estimates or the discrepancy with the sponsor’s analysis. They should be read as conditional examples about the information needed to detect specified effects, not as evidence about whether the completed study had adequate power for its intended primary analysis.

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 = -0.140; pooled standard deviation σ = 0.649.
2. n = 2 × (1.96 + 0.842)² × 0.649² / -0.140² = 337.2, rounded up to 338 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 <- -0.14                      # observed difference in means
sigma <- 0.648899575190672                     # 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(3246724)
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 = 338 (80% power), 452 (90% power)
 75% of observed effect: n per arm = 600 (80% power), 803 (90% power)
 50% of observed effect: n per arm = 1,349 (80% power), 1,806 (90% power)
power.t.test: 338.2 
Simulated power at n = 338 per arm: 0.796 (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. Analyses Reported by the Sponsor

The registry reports the sponsor’s primary analysis as ANCOVA, labelled non-inferiority, with p <0.05. It does not report the adjusted estimate, confidence interval, non-inferiority margin, covariates, or analysis population. Those omissions limit independent assessment of the result, including its magnitude, direction, and precision.

The recalculated contrasts use posted means, standard deviations, and group sizes to make simple, unadjusted comparisons between each non-cataract procedure category and the cataract category. They are not adjusted and do not estimate the sedation-route contrast. The sponsor analysis and the recalculations therefore differ in both method and the comparison that can be recovered from the posted summaries.

The registry record flags a discrepancy. For the intended primary comparison, the sponsor’s own analysis takes precedence over these recalculations. This does not mean the missing details can be inferred from the sponsor’s p-value: the record does not provide enough information to reproduce the analysis or assess its non-inferiority margin. The recalculations remain useful only as descriptive, unadjusted context for the procedure-category summaries. They should not be used to overrule the sponsor’s treatment analysis or to claim that the route comparison has been independently confirmed.

15. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when several endpoints, groups, or contrasts are examined. The more comparisons considered, the greater the chance that at least one result may appear statistically notable by chance. The registry record lists a primary endpoint, two secondary endpoints, four procedure categories, and multiple recalculated category contrasts. The recalculated p-values are explicitly unadjusted. A multiplicity procedure, if any, is not reported in the registry record.

The sponsor’s primary analysis is reported as ANCOVA with a non-inferiority label, but the record does not describe how the primary analysis was prioritized relative to other analyses, whether there was a prespecified testing sequence, or how secondary outcomes were handled. It also does not report the non-inferiority margin or the full model. The reported p-value should therefore be read as a result of the sponsor analysis, not as a complete account of the statistical evidence across all outcomes.

Missing data can also affect interpretation. The registry record does not report whether every randomized participant contributed a primary endpoint score, how incomplete surveys were handled, or whether any participants were excluded from an analysis. It does not describe imputation, sensitivity analyses, or the reasons for missing outcome data. The posted category group sizes should not be assumed to describe the analysis population for the sponsor’s adjusted model unless the record makes that connection.

The analysis population is not reported in the registry record. In randomized trials, conclusions can depend on whether analyses include all randomized participants, only participants who received the assigned intervention, or a subset meeting other criteria. Non-inferiority conclusions can be particularly sensitive to analysis populations and missing-data assumptions. Without those details, readers cannot assess how robust the reported conclusion is to exclusions or incomplete outcomes.

These gaps do not establish that the analyses were conducted improperly. They mean the registry record does not provide enough information to independently evaluate multiplicity control, missing-data handling, or the population used for the sponsor’s primary analysis.

16. 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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: in-patient hospitalization (1.2%).

The adverse-event summaries report serious adverse events by procedure category. The cataract-procedure category lists 1 serious adverse event among 85 at risk, with in-patient hospitalization reported as the serious term at 1.2%. The retina category lists 0 among 84, the cornea category 0 among 70, and the glaucoma category 0 among 44. Deaths are reported as 0 in every category.

These are counts from the registry record, not comparisons of serious-event risk between oral and intravenous sedation. The event summaries are grouped by procedure category and do not identify the sedation route associated with each event. A small number of observed events, including no events in a category, does not establish that the underlying risk is absent or equal between routes. The record does not provide a route-specific safety estimate or confidence interval.

The registry also lists other, non-serious adverse events by category, but the posted counts do not by themselves explain severity, timing, relatedness, or clinical course. The record’s summary is not a substitute for a detailed safety analysis. Readers should keep these descriptive event counts separate from conclusions about comparative safety or the primary satisfaction endpoint.

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

The registry record describes a randomized comparison intended to evaluate patient satisfaction after oral versus intravenous sedation for ocular procedures. The primary measure is a patient-reported mean score from a survey with responses graded from 1 to 6. The posted category summaries show mean satisfaction scores and their variability for cataract, retina, cornea, and glaucoma procedures.

Those summaries do not directly show how satisfaction differed between the sedation routes. The recalculated estimates compare procedure categories with one another, not oral sedation with intravenous sedation. The sponsor’s own analysis is reported as ANCOVA and labelled non-inferiority, but its estimate, confidence interval, and margin are not reported in the registry record. The discrepancy flag means the sponsor’s own analysis takes precedence over the simple recalculations for the intended treatment comparison.

Consequently, the posted material does not allow a reader to judge the magnitude or precision of the route effect from the sponsor’s result. The reported p-value does not establish that the routes produce identical satisfaction, nor does it show how close the result is to a non-inferiority margin. The registry record also does not report the missing-data approach, analysis population, or multiplicity plan needed to assess the robustness of the conclusion.

The study summary describes potential practical reasons to consider a capsule route, but those are stated motivations, not outcomes established by the posted satisfaction summaries. The results presented do not quantify patient costs, hospital costs, eating before a procedure, or operating-room time. They also do not by themselves establish comparative safety or procedural success.

The appropriate interpretation is therefore bounded: the record reports an intended randomized route comparison and sponsor-reported non-inferiority analysis, alongside descriptive satisfaction results by procedure category. The category recalculations should not be mistaken for the primary treatment effect. The registry’s limited reporting prevents a complete independent evaluation of the non-inferiority claim.

18. Why This Trial Matters Statistically

This trial raises a useful statistical distinction between the clinical comparison a study intends to make and the groups used to display its posted results. The stated question concerns oral versus intravenous sedation. The available summaries are grouped by procedure category, and the simple recalculations compare those categories with cataract procedures. Recognizing that difference prevents a descriptive contrast from being misread as a treatment effect.

The non-inferiority label also illustrates why an estimate and confidence interval matter alongside a p-value. Non-inferiority depends on a prespecified margin and on where the plausible treatment effects lie relative to that margin. The registry record reports the analysis method label and p-value but not the quantities needed to understand that relationship. Statistical reporting that includes the margin, adjusted estimate, and interval would make the claim easier to evaluate.

The study also separates patient-reported satisfaction from clinician-reported satisfaction. These endpoints reflect different perspectives and should not be combined into a single conclusion without an explicit analysis plan. Their interpretation depends on the outcome definitions, analysis populations, and multiplicity strategy, details not fully reported in the registry record.

Finally, the sample-size illustrations show how planning targets depend on the effect size being considered. Smaller effects require more participants per arm under the stated assumptions. These illustrations are not a reconstruction of the original design and do not indicate observed power. They demonstrate why the planned effect and design assumptions should be reported prospectively, especially for a non-inferiority question where the margin shapes the required precision.

19. 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.

A central limitation of the registry record is that the posted primary outcome summaries are organized by procedure category, while the clinical question is a comparison of sedation routes. The sponsor’s analysis is labelled non-inferiority, but the treatment-effect estimate, confidence interval, and non-inferiority margin are not reported. The record therefore does not allow independent appraisal of the primary route comparison.

The record identifies ANCOVA but does not report the covariates or model specification. It does not describe the randomization procedure, allocation concealment, or how masking was maintained, beyond the design labels and the description that participants received both a capsule and an IV without knowing which administered sedation. Exact route-specific dosing and the relationship between the listed substances and study groups are not reported in the registry record.

The record does not report how incomplete surveys were handled, the analysis population, or whether sensitivity analyses were performed. It does not describe multiplicity control across the primary and secondary outcomes or across contrasts. These omissions limit assessment of the robustness and scope of the reported findings. The original sample-size rationale and design assumptions are also not reported; planning illustrations based on observed effects cannot fill that gap.

The adverse-event summaries are grouped by procedure category rather than sedation route, and the record does not report route-specific comparative safety estimates. The satisfaction endpoint is based on a survey, but validation and a threshold for a meaningful score difference are not reported. Finally, the registry record is a limited reporting source: absent details should be understood as unreported in that record, not as proof that the study did not collect or analyze them.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: Oral Versus Intravenous Sedation for Ocular Procedures — NCT03246724.
• Registry record last updated 2020-08-19; status last verified 2020-08.
• Results first posted 2020-08-19.
• 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.

23. Record Summary

NCT03246724 is a completed, randomized, parallel-group study sponsored by Boston Medical Center and described as a single-center, double-blind, double-dummy comparison of oral and intravenous sedation for ocular procedures. The record reports enrollment of 327 and primary completion on 2019-11-30.

The primary endpoint is patient satisfaction, measured as a mean score from a 12-question survey graded from 1 to 6. Posted outcome summaries are grouped by cataract, retina, cornea, and glaucoma procedures. The sponsor reports an ANCOVA analysis labelled non-inferiority with p <0.05, but its estimate, confidence interval, and margin are not reported in the registry record.

Unadjusted recalculations compare procedure categories, not sedation routes. Because the record flags a discrepancy, the sponsor’s own analysis takes precedence for the intended treatment comparison. The missing analysis details limit independent interpretation of the non-inferiority result.