The Emergency Department Sedation Pilot Trial: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Emergency Department Sedation Pilot Trial (NCT04410783), a non-randomized na study. The primary outcome is Participant Recruitment.

2. Clinical Question

The registry describes a study of whether an educational initiative could be implemented in emergency departments caring for mechanically ventilated patients. The intervention is education, and the before group received standard post-intubation sedation before that initiative. The after group received post-intubation sedation after the initiative. This arrangement can describe changes across periods, but it cannot by itself separate an initiative’s effect from other differences between those periods.

The stated primary endpoint is a count of eligible participants included in the study for analysis. That endpoint addresses recruitment and feasibility, not the clinical effect of sedation practices. Ventilator-free days, ICU-free days, hospital-free days, delirium, and mortality are listed as secondary outcomes. The registry record does not report numerical results for those outcomes in the registry record for this analysis.

3. Trial Design

The Emergency Department Sedation Pilot Trial is described as a multicenter, prospective, before-and-after study. It was conducted at Washington University in St. Louis School of Medicine, Cooper Hospital of Rowan University, and University of Iowa Carver College of Medicine. The registry lists the design as non-randomized, unmasked, and single-group. It also identifies education and standard post-intubation sedation practices as interventions.

The before group consisted of mechanically ventilated emergency department patients receiving standard post-intubation sedation before an educational initiative on targeted sedation. The after group consisted of patients receiving post-intubation sedation after an initiative aimed at improving emergency department sedation practices. Because assignment was not randomized and the comparison is across before-and-after periods, the groups are not a like-for-like control comparison. Changes between periods may reflect the initiative, changes in the patients or clinical setting, or other time-related factors; the registry record does not report an analysis that distinguishes these possibilities.

The registry lists an enrollment of 1771 and study dates from 2020-09-14 to 2022-05-28, with status completed. The brief summary describes 344 mechanically ventilated patients included in the study. The participant flow description states that 1771 participants were assessed for eligibility and 1356 were not eligible. The record’s primary endpoint description is a count of eligible participants included for analysis, but a numerical result for that endpoint is not reported in the registry record.

The study is marked as not applicable for phase. The registry identifies recruitment as the primary outcome, with a timeframe through study completion, described as an average of 1 year. It lists nine outcome measures and no analyses. The record does not report a randomized allocation procedure, masking, or a statistical analysis plan.

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

Analysis population for the primary outcome, as defined in the registry: These numbers reflect the number of eligible participants who were included in the study for analysis (i.e. the final study population). As mentioned above in "Participant Flow", there were 1771 participants assessed for eligibility and 1356 were not eligible for the study. Therefore, the overall number of participants analyzed (i.e. 415) relects this.

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 Participant Recruitment, measured over Through study completion, an average of 1 year.

The primary endpoint is participant recruitment, measured as a count of eligible participants included in the study for analysis. The registry describes this count as the final study population. A recruitment endpoint is relevant to a feasibility study because it can describe whether eligible patients were identified and included in a study of the proposed care process. It does not measure sedation depth, clinical benefit, or harm directly.

The endpoint’s stated timeframe is through study completion, described as an average of 1 year. The registry record includes an enrollment figure of 1771 and says that 1771 participants were assessed for eligibility, with 1356 not eligible. The brief summary describes 344 patients included in the study. A numerical result for the primary recruitment endpoint is not reported in the registry record among the registry entries, so the endpoint cannot be interpreted as a completed estimate of recruitment from this information alone.

The study’s broader goal concerns the feasibility of implementing targeted sedation and the possible reduction of unnecessary deep sedation, alongside improvement in clinical outcomes. Recruitment alone cannot answer those clinical questions. The registry lists ventilator-free days, ICU-free days, hospital-free days, delirium, and mortality as secondary outcomes, but their numerical results are not reported in the registry record in the registry record for this analysis. The distinction matters: an endpoint can describe whether a study enrolled patients, while separate outcome measures are needed to describe patient experiences and clinical events.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a before-and-after comparison establish?

In general, a before-and-after study compares observations from a period before an intervention with observations from a period after it. It can show whether measured outcomes differ across those periods. The comparison is less protected against bias than randomized allocation because participants are not assigned by chance to concurrent intervention and control conditions. Differences over time, changes in the patients receiving care, or other changes in practice may contribute to an observed difference. These are general limitations of the design, not evidence that any particular change occurred in this study.

The registry classifies this study as non-randomized and identifies the arms as a before group and an after group. Its record explicitly cautions that the arms are not a like-for-like control comparison. This is important when interpreting any apparent change: a descriptive contrast between periods is not automatically an estimate of the initiative’s causal effect.

What does a count endpoint tell the reader?

In general, a count records how many eligible observations meet a defined inclusion criterion. Here, the primary endpoint is the count of eligible participants included in the study for analysis. Such a measure can inform recruitment feasibility, but it does not quantify an intervention effect on sedation or a patient outcome. The registry also gives participant flow information: 1771 were assessed for eligibility and 1356 were not eligible. The brief summary describes 344 patients included. The primary endpoint result itself is not reported in the registry record among the registry entries available for this analysis.

A count is interpreted in the context of how it was defined and who could be included. The registry describes the count as the final study population, but the primary endpoint description is truncated in the record details. Further details about the endpoint’s operational definition, including any additional inclusion or exclusion rules, are not reported in the registry record.

How should uncertainty be considered?

In general, an estimate is more informative when accompanied by a measure of uncertainty, such as a confidence interval. A confidence interval describes a range of values compatible with the data and the statistical method used; it does not guarantee that the true value lies within that range. Wider intervals indicate less precision, while narrower intervals indicate greater precision, subject to the assumptions of the method.

The record details do not include outcome estimates, confidence intervals, p-values, or listed analyses. Without those results, it is not possible to describe the precision of a clinical outcome comparison or to evaluate a statistical test. The presence of a listed endpoint does not itself show that a result was estimated or reported.

Why does the study structure matter for interpretation?

In general, statistical adjustment can account for measured differences between groups, but it cannot automatically remove bias from unmeasured differences. A before-and-after design also makes intervention status coincide with time period: the intervention is introduced after the earlier period. Separating an intervention effect from period-related changes therefore requires suitable design features or analysis assumptions. The registry record does not report a statistical plan or analyses that would support such separation.

The record labels the design single-group, while describing before and after groups around an educational initiative. The most cautious reading is to follow the posted description: the study is prospective and before-and-after, is non-randomized, and does not offer a like-for-like randomized control comparison. The registry does not report masking. In general, lack of masking can matter when outcomes involve judgment or recording, though the registry entries do not identify whether outcome assessment was masked or how each outcome was measured.

How should planning illustrations be read?

In general, a sample-size calculation estimates the number of participants or events that would be needed under specified assumptions to detect a defined effect with a chosen statistical procedure. It is a planning exercise, not a result of the study and not evidence that the study had a particular probability of detecting an effect after completion. The registry’s stated planning assumptions use a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The calculation is described as an illustration based on the observed effect, with the effect to detect expressed as a stated fraction of that observed effect. The registry also distinguishes planning quantities for participants per arm from total events for time-to-event outcomes.

These assumptions do not establish that the trial was designed with those values. The registry record does not report the trial’s own sample-size justification, and the planning illustrations should not be called observed power. Because numerical illustration results are not included in the registry record for this analysis, no planning quantity can be interpreted. More generally, a planning estimate depends on its assumptions, including the target effect and the method used; changing those assumptions changes the resulting estimate.

For outcomes that are counts of participants with an event, general methods may compare event counts or event proportions, while time-to-event outcomes use methods that account for when events occur. The listed secondary outcomes include both event counts, such as participants with delirium, and duration or free-day outcomes. However, the registry entries do not provide the outcome definitions, analysis methods, estimates, or uncertainty measures needed to assess how those outcomes were analyzed.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Before Group", "After Group")
n      <- c(196, 219)
events <- c(196, 219)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Before Group  196  196  100.0  98.1  100.0  98.1  100.0  98.1  100.0
ARM  After Group  219  219  100.0  98.3  100.0  98.3  100.0  98.3  100.0

11. Multiplicity, Missing Data and Analysis Populations

The registry lists nine outcome measures, including participant recruitment as the primary outcome and ventilator-free days, ICU-free days, hospital-free days, delirium, and mortality as secondary outcomes. It reports no analyses in the registry record for this analysis. A statistical plan describing how these outcomes were tested, prioritized, or interpreted is not reported in the registry record.

In general, testing multiple outcomes can increase the chance that at least one result appears noteworthy by chance. Researchers may address this issue through a prespecified hierarchy, adjustment procedures, or a clearly exploratory interpretation. Which approach is appropriate depends on the research question and analysis plan. The registry record does not report whether any multiplicity strategy was planned or used, so the results cannot be characterized as adjusted or unadjusted for multiple testing.

Missing data also affect interpretation. In general, outcome data may be unavailable because a participant did not complete follow-up, an outcome was not measured, or a record was incomplete. The reason and amount of missingness can influence an estimate, particularly if the missingness is related to participant characteristics or outcomes. The registry entries do not report missing-data counts, reasons, handling procedures, or sensitivity analyses. They also do not report outcome-specific denominators for the listed secondary outcomes.

The primary recruitment outcome refers to eligible participants included for analysis, but the record does not report a numerical primary endpoint result among the registry entries. The analysis population definitions beyond that description are not reported in the registry record. It is therefore not possible to determine whether the clinical outcome analyses included all enrolled patients, only participants with available measurements, or another analysis population.

12. 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

Serious events with the highest arm-level rate: inadvertent extubation, device removal, awareness with paralysis (5.0%).

The registry reports serious adverse event counts of 8 in the Before Group, with 196 at risk, and 11 in the After Group, with 219 at risk. It reports 0 other adverse events in the Before Group, with 196 at risk, and 0 in the After Group, with 219 at risk. Death counts are listed separately as 40 for the Before Group and 22 for the After Group. These figures should be read as the registry’s posted counts, not as evidence that the educational initiative caused an event or prevented one.

The record lists “Inadvertent extubation, device removal, awareness with paralysis” among the serious terms and reports 5.0%. It does not specify the denominator or group attribution for that percentage in the registry record. It also does not explain whether the listed terms can overlap or how they relate to the overall serious-event counts. Those details are needed before interpreting the term-specific figure as a group comparison.

In general, safety counts are most interpretable when event definitions, observation periods, denominators, and attribution rules are clear. The registry entries do not provide those details for all figures, nor do they report a comparative safety analysis. The before-and-after design further limits causal interpretation. The counts describe reported events; they do not establish whether the initiative or sedation practices caused them.

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

The registry record documents a prospective, multicenter before-and-after study of an educational initiative intended to improve emergency department sedation practices for mechanically ventilated patients. It identifies participant recruitment as the primary outcome and lists several clinical outcomes as secondary measures. It also reports serious adverse event counts for the before and after groups. These registry entries describe what the study set out to examine and some posted safety information.

The record does not provide a numerical result for the primary recruitment endpoint in the registry record for this analysis. Although the brief summary describes 344 patients included, the primary endpoint is defined as a count of eligible participants included for analysis. Those details should not be treated as interchangeable endpoint reporting without a clearly posted endpoint result. The clinical outcome results and their uncertainty are also not reported in the registry record among the registry entries.

The non-randomized before-and-after design can describe changes between periods, but it cannot ensure that the periods are comparable. In general, a difference across periods could reflect the educational initiative, other changes over time, differences in the patients, or a combination. The registry itself cautions that the arms are not a like-for-like control comparison. Thus, even if a clinical outcome contrast were reported, the design would call for careful interpretation rather than an unqualified causal claim.

The serious adverse event and death counts are descriptive. The record does not establish causal attribution, and the registry entries do not fully define the relationship among the different safety figures. The posted counts should not be used to conclude that the intervention improved or worsened safety.

In general, a registry record can help readers understand the stated design, outcome definitions, and posted results, but its completeness matters. Here, the registry entries available do not include the statistical analysis plan, estimates for the clinical outcomes, uncertainty measures, missing-data handling, or a multiplicity strategy. Accordingly, the record supports a description of the study and its reported counts, but not a conclusion about whether the educational initiative changed clinical outcomes.

14. Why This Trial Matters Statistically

This study raises a practical statistical question: how to evaluate a change in clinical practice when the intervention is introduced across time rather than assigned randomly. A before-and-after design can be useful for describing implementation and generating evidence about feasibility. At the same time, the timing of the intervention creates an interpretive challenge because the before and after periods may differ in ways other than the educational initiative.

That challenge is especially relevant when the stated goal includes clinical outcomes. Recruitment, sedation depth, ventilator-free days, ICU-free days, hospital-free days, delirium, and mortality represent different kinds of measures. A recruitment count can describe participation, while clinical outcomes describe events or time spent in specified states. Each requires a clear definition and analysis appropriate to its form. The registry lists several outcomes, but their numerical results and analysis methods are not reported in the registry record.

The record’s explicit warning that the arms are not a like-for-like control comparison is statistically important. It directs attention to causal inference, not just whether a before-and-after contrast can be calculated. In general, a comparison may be numerically precise yet still vulnerable to bias if the groups or periods differ in relevant ways.

The record also illustrates why transparent reporting of outcome results, analysis populations, missing-data handling, and statistical plans matters. Those details allow readers to judge not only the direction of an estimate but also its uncertainty and the assumptions behind it. The registry entries support discussion of the design and posted safety counts, while leaving key information needed for clinical outcome interpretation unreported.

15. 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 study is non-randomized and compares a before group with an after group surrounding an educational initiative. The registry explicitly states that the arms are not a like-for-like control comparison. This limits the ability to attribute any difference between periods to the initiative, because other time-related or group differences may contribute. The record does not report an analysis that addresses those potential differences.

The registry labels the design single-group, while describing before and after groups. The registry entries do not further explain how that design label relates to the comparison or provide additional design details. Masking is listed as none. The record does not report whether outcome assessment or data recording followed any masking procedures.

The primary endpoint is described as participant recruitment, but a numerical result for that endpoint is not reported in the registry record among the registry entries available for this analysis. The brief summary describes 344 patients included, while the record lists enrollment of 1771 and states that 1771 participants were assessed for eligibility and 1356 were not eligible. The available endpoint description is truncated, so further reconciliation or detail about the final analysis population is not reported in the registry record.

The registry lists nine outcome measures and no analyses in the registry record. Numerical results for the secondary clinical outcomes, statistical estimates, confidence intervals, p-values, and analysis methods are not reported in the registry record. Nor are missing-data procedures, outcome-specific denominators, a multiplicity strategy, or the trial’s own sample-size justification reported.

Safety reporting also has limits in the registry entries. The serious event term is accompanied by 5.0%, but its denominator and group attribution are not specified. The relationship between death counts and serious adverse event counts is not explained. These gaps restrict interpretation of the safety figures and prevent a detailed comparative assessment.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: The Emergency Department Sedation Pilot Trial — NCT04410783.
• Registry record last updated 2022-12-28; status last verified 2022-12.
• Results first posted 2022-12-28.
• 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.

19. Record Summary

The Emergency Department Sedation Pilot Trial is a completed, prospective, multicenter before-and-after study of an educational initiative intended to improve sedation practices for mechanically ventilated emergency department patients. The registry lists the study as non-randomized, unmasked, and single-group. The study dates are 2020-09-14 to 2022-05-28.

The primary outcome is participant recruitment, defined as a count of eligible participants included for analysis. The brief summary describes 344 patients included; the record also lists 1771 assessed for eligibility and 1356 not eligible. Ventilator-free days, ICU-free days, hospital-free days, delirium, and mortality are listed as secondary outcomes. Numerical results for these clinical outcomes are not reported in the registry record among the registry entries.

Serious adverse event counts are 8 in the Before Group and 11 in the After Group; other adverse event counts are 0 in each group. Death counts are 40 and 22, respectively. The record cautions that the arms are not a like-for-like control comparison, so these figures do not establish causal effects.