Preemptive Analgesia With Celecoxib for Acute Dental Pain Management: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Preemptive Analgesia With Celecoxib for Acute Dental Pain Management (NCT04790812), a randomized phase 4 study. The primary outcome is Pain as Assessed by a Visual Analogue Scale (VAS).

2. Clinical Question

The trial asks whether adding acetaminophen to preoperative celecoxib is associated with a different postoperative pain score than celecoxib with placebo. Because both groups received celecoxib, the contrast concerns the combination regimen versus celecoxib alone, not celecoxib versus no active treatment. The primary outcome is a mean score on a 0-10 scale, with 10 indicating worse pain.

The posted outcome summaries include four participants in the celecoxib-plus-placebo group and six in the celecoxib-plus-acetaminophen group. These are the numbers contributing to the posted primary outcome summaries; they should not be treated as the overall enrollment. The registry record reports enrollment of 65, but does not explain the difference between enrollment and the outcome-summary group sizes.

3. Trial Design

The study is listed as a phase 4, randomized, double-masked, parallel-group trial and is marked completed. Its stated purpose is to compare postoperative pain after a single preemptive dose of celecoxib plus placebo with pain after celecoxib plus acetaminophen, before impacted third molar surgery. The trial record identifies postoperative pain as the condition under study.

Participants in the celecoxib-plus-placebo group were assigned a single oral dose of celecoxib 200 mg with placebo 30 to 60 minutes before the dental procedure. Participants in the combination group were assigned celecoxib 200 mg with acetaminophen 1000 mg at the same preoperative interval. Thus, the intended comparison holds celecoxib and dosing time constant while varying whether acetaminophen is included.

The parallel-group design assigns participants to one regimen rather than describing repeated treatment periods within the same participant. Randomization is intended, in general, to help make treatment groups comparable at the start of a study. Masking is intended, in general, to reduce the influence of treatment knowledge on care, participant responses, or outcome assessment. The record labels the study double-masked but does not specify who was masked or how masking was maintained.

Enrollment is listed as 65. The study start date is 2021-04-22, primary completion is listed as 2023-03-01, and status is completed. The registry record does not report the randomization method, allocation ratio, detailed eligibility criteria, recruitment setting, or the basis for the planned enrollment. It also does not report how many participants were assigned to each arm in the full trial. The primary outcome summaries include four and six participants in the two groups, respectively, so those outcome counts do not describe the full enrollment.

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 Pain as Assessed by a Visual Analogue Scale (VAS), measured over 3 hours after procedure.

The primary endpoint is pain assessed with a visual analogue scale three hours after the procedure. The registry describes a questionnaire using a 0-10 pain scale with visual “Faces” corresponding to numerical values; 10 indicates worse pain. The endpoint is reported as a mean score with a standard deviation for each group.

A visual analogue pain measure is used to capture a participant’s reported pain intensity at a specified time. It provides a common scale for describing responses across participants and can be summarized with a group mean. The mean communicates the average score in the group, while the standard deviation describes how dispersed individual scores are around that mean. These summaries answer different questions: the mean describes the group’s central level, and the standard deviation describes variation among participants.

The three-hour time point fixes when the reported pain assessment is intended to occur. It is one snapshot of pain after surgery, not a description of pain over the entire recovery period. The registry record does not report further details about questionnaire administration, the precise handling of incomplete responses, or whether the primary endpoint was assessed at other times as well. Although the record describes the scale as a visual analogue scale, it does not provide additional information on its validation or scoring procedure.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is a continuous score summarized by its mean and standard deviation. These statistics provide a compact description of the observed scores in each treatment group. The mean gives the arithmetic average, while the standard deviation indicates how widely individual scores vary around that average. Neither statistic alone is a direct estimate of the uncertainty in a between-group treatment effect.

What does a group mean describe?

A group mean condenses the scores of the participants included in that group into one value. Here, the reported means are 4.0 for celecoxib plus placebo and 2.33 for celecoxib plus acetaminophen. Because higher scores indicate worse pain, the direction of the descriptive summaries can be understood from the scale definition. However, a difference in observed means is not, by itself, evidence that the regimens produce different outcomes in the broader population. Sampling variability must also be considered, and the registry record does not report a formal between-group estimate or its uncertainty.

What does the standard deviation tell the reader?

The standard deviation describes the spread of participant scores within a group. The reported standard deviations are 3.26 and 3.01. They are not measures of uncertainty around the mean, and they are not measures of the difference between groups. A confidence interval for a mean or treatment contrast would address precision more directly. In general, a confidence interval gives a range of values compatible with the data under the analysis assumptions. No confidence interval for the primary outcome comparison is reported in the registry record.

Why does the small outcome count matter?

The primary outcome summaries include four participants in one group and six in the other. With small groups, estimates are sensitive to the particular participants observed; a small number of unusually high or low scores can noticeably affect the mean and standard deviation. Precision is generally limited when little outcome information is available. This is a general statistical consideration, not evidence about why the outcome counts are small in this trial. The registry record does not report the reasons for the counts or the amount and pattern of missing outcome data.

The 0-10 scale has a fixed range, and its upper end is defined as worse pain. Reporting a mean is a familiar way to summarize scores, but the mean and standard deviation do not show the complete distribution. They do not reveal how many participants selected each score, whether responses clustered at particular values, or whether values were concentrated near either end of the scale. Those details are not reported in the registry record.

Why is a direct group comparison important?

A treatment question concerns a contrast between assigned groups, not only the separate summaries within each group. An inferential analysis would ordinarily estimate the difference between groups and quantify its uncertainty, with methods suited to the design and endpoint. A p-value, when reported, addresses compatibility with a specified null hypothesis under model assumptions; it is not a measure of clinical importance or the probability that a treatment works. A confidence interval would help show which treatment contrasts remain compatible with the data. Neither a p-value nor a confidence interval for this primary comparison is reported in the registry record, and the registry lists zero analyses.

General statistical methods for continuous outcomes may include comparisons of means when their assumptions are appropriate. The assumptions, selected test, adjustment variables, and analysis model for this trial are not reported in the registry record. It would therefore be inappropriate to attribute a particular test or model to the investigators or to reconstruct a sponsor analysis from the group summaries. The displayed means and standard deviations should be read as descriptive, not as a substitute for the unreported inferential analysis.

How should repeated outcomes be considered?

The registry lists 17 outcome measures and nine posted secondary outcomes. Multiple outcomes can create multiplicity concerns: when many hypotheses are tested, the chance of at least one apparently noteworthy finding can increase. In general, investigators may address this by prespecifying a primary outcome, defining a testing hierarchy, or adjusting inference. The registry record does not report a multiplicity strategy, a testing hierarchy, or the results of secondary-outcome analyses. The repeated descriptions of categorical questionnaire assessments do not establish which analyses were planned or how results were to be interpreted.

The registry record includes a sample-size-planning illustration based on an observed effect, but it does not report the trial’s own design justification in the information available for this analysis. Planning illustrations are not observed power and do not establish that a trial was adequately sized. The record does not report the assumptions used for the trial’s original enrollment target or the anticipated precision of the primary outcome. These omissions limit evaluation of how the study’s design related to the question it set out to answer.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Celecoxib Plus Placebo", "Celecoxib Plus Acetaminophen")
n   <- c(4, 6)
m   <- c(4, 2.33)
sp  <- c(3.26, 3.01)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Celecoxib Plus Placebo  4  4.000  3.260  -1.187  9.187
CARM  Celecoxib Plus Acetaminophen  6  2.330  3.010  -0.829  5.489

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists 17 outcome measures and nine posted secondary outcomes. The primary endpoint is pain on a visual analogue scale three hours after the procedure. When a study assesses multiple outcomes or time points, multiplicity matters because repeated statistical testing can increase the chance of finding an apparently notable result by chance. In general, a prespecified testing hierarchy or an adjustment strategy can clarify how multiple results are to be interpreted. The registry record does not report a multiplicity plan, hierarchy, or adjustment method. It also lists zero analyses, so no inferential results for the primary or secondary outcomes are posted.

The primary outcome summaries include four participants in the celecoxib-plus-placebo group and six in the celecoxib-plus-acetaminophen group. Enrollment is listed as 65. The registry record does not explain the difference between enrollment and the numbers contributing to these outcome summaries. It does not report whether the difference reflects missing measurements, exclusions, withdrawal, or another reason; none of those explanations should be assumed.

The record does not describe imputation, other missing-data handling, participant flow by treatment group, or sensitivity analyses. It also does not identify the analysis population, such as whether the primary analysis included everyone randomized or only participants with available measurements. Without those details, it is not possible to assess how missingness or analysis-population choices may have affected the posted summaries. The reasons for unavailable outcome information and the consequences for interpretation are not reported in the registry record.

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.

The registry record reports safety counts separately for the two treatment groups. In the celecoxib-plus-placebo group, 23 participants were at risk for the serious adverse event summary and 23 for the other adverse event summary; zero serious events and zero other events are reported. In the celecoxib-plus-acetaminophen group, the corresponding numbers at risk are 26 and 26, with zero serious events and zero other events reported. Deaths are reported as zero in both groups.

These figures describe the recorded counts among the participants included in the safety summaries. They do not show that an event could not occur, or that the regimens have no risk. When no events are recorded, the data provide limited information about the frequency of uncommon events, particularly when the numbers at risk are limited. The registry record does not report further detail on safety monitoring, event definitions, or the process used to collect adverse event information.

The safety denominators differ from the primary outcome-summary counts. The registry record does not explain the relationship between these groups of participants or why the numbers differ. The absence of recorded events in these summaries should not be extended to participants who are not represented in them. These counts are safety observations in this trial, not a general guarantee about safety.

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

The registry record describes a randomized comparison of celecoxib plus placebo with celecoxib plus acetaminophen before impacted third molar surgery. It reports mean pain scores at three hours after the procedure and the associated standard deviations. The posted means are 4.0 and 2.33, with standard deviations of 3.26 and 3.01, respectively. The scale runs from 0 to 10, with higher scores indicating worse pain. These values describe the participants represented in the summaries.

They do not, on their own, establish a reliable treatment effect. The outcome groups include four and six participants, and no between-group estimate, confidence interval, or p-value is reported. The registry lists zero analyses. Without an inferential comparison, the uncertainty around the difference between regimens cannot be assessed from the posted results. A difference between descriptive means should not be treated as proof of a difference in the population.

The results also do not establish equivalence, non-inferiority, or absence of effect. Those questions require defined criteria and suitable analyses; the registry record does not report such criteria or analyses. Because both arms include celecoxib, the comparison is not a test of celecoxib against no active treatment. It addresses the addition of acetaminophen to celecoxib, as described in the assigned regimens.

The endpoint captures pain at one specified time. It cannot by itself describe pain at other times, broader recovery, or outcomes not reported in the primary summaries. The record lists additional outcomes, but does not post analyses for them. It also does not explain why the primary outcome summaries include only a portion of the overall enrollment of 65. These features limit what can be concluded from the posted record. The most supportable reading is descriptive: the registry reports group means and variability for a small number of outcome observations, while the comparative uncertainty and wider outcome data are not reported.

14. Why This Trial Matters Statistically

The trial illustrates the distinction between describing group outcomes and estimating a treatment contrast. A mean and standard deviation for each arm tell readers what the observed scores looked like among participants represented in those summaries. They do not answer, by themselves, how precisely the regimens differ or whether the observed contrast is compatible with chance variation. A direct estimate with uncertainty is central to interpreting a randomized comparison.

It also highlights the importance of connecting enrollment to analyzed outcomes. The registry lists enrollment of 65, while the posted primary outcome summaries include four and six participants. Without participant flow, reasons for missing measurements, and a defined analysis population, readers cannot determine how representative those summaries are of the randomized trial population. This is a reporting limitation, not an explanation for what happened to participants.

The outcome is a patient-reported pain score at a prespecified time after surgery. That makes the measurement and its timing central to interpretation: the score reflects a specific assessment, rather than every aspect of postoperative experience. The registry describes the scale and direction but does not report its administration details or the distribution of individual responses.

Finally, the record lists multiple outcomes but no analyses. This underscores why outcome registration and results reporting need to be read together. A list of outcomes identifies what the record says was measured, but without analysis results or a stated multiplicity approach, it cannot show how the findings across outcomes were evaluated. The trial is statistically informative as an example of the limits of sparse result reporting: numerical summaries can be presented, yet the key comparative uncertainty and analysis details can remain unavailable.

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 most important limitation for interpretation is the small number of participants represented in the primary outcome summaries: four in the celecoxib-plus-placebo group and six in the celecoxib-plus-acetaminophen group. The registry record lists enrollment of 65 but does not account for the difference. Participant flow, exclusions, and reasons for missing outcome measurements are not reported in the registry record.

The record provides group means and standard deviations but no estimate of the between-group contrast, confidence interval, or p-value. It lists zero analyses. Consequently, readers cannot assess the precision of the comparison or review the methods used for inference. The analysis model, any adjustment variables, and the analysis population are not reported in the registry record.

There is limited detail about conduct: the record does not describe the randomization procedure, allocation ratio, masking implementation, or further eligibility criteria. It also does not explain the original sample-size rationale. These missing details make it difficult to assess design and analysis choices from the registry record alone.

The primary endpoint represents one pain assessment three hours after the procedure. Its summaries do not describe outcomes at other times, and the record does not post analyses for the listed secondary outcomes. Multiple outcomes make a prespecified interpretation strategy relevant, but a multiplicity approach is not reported. Safety counts are also limited to the reported numbers at risk and recorded events; further safety-collection details are not reported.

These limitations concern the information available in the registry record. They do not establish that particular procedures were absent from the trial; they indicate that those details are not reported in the registry record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Preemptive Analgesia With Celecoxib for Acute Dental Pain Management — NCT04790812.
• Registry record last updated 2024-03-27; status last verified 2024-02.
• Results first posted 2024-03-27.
• 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

NCT04790812 is listed as a completed phase 4 randomized, double-masked, parallel-group study of preoperative celecoxib with placebo versus celecoxib with acetaminophen for pain after impacted third molar surgery. Enrollment is listed as 65. The primary endpoint is mean pain on a 0-10 visual analogue scale three hours after the procedure, with 10 indicating worse pain.

The posted primary outcome summaries include four participants in the celecoxib-plus-placebo group, with mean 4.0 and standard deviation 3.26, and six participants in the celecoxib-plus-acetaminophen group, with mean 2.33 and standard deviation 3.01. The registry record lists zero analyses and does not report a between-group estimate or its uncertainty. It does not explain the difference between enrollment and the primary outcome-summary counts. Serious adverse events, other adverse events, and deaths are reported as zero in the posted safety groups.