This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Randomized, Double-Blind, Single-Dose, Efficacy and Safety Study of Test Acetaminophen Tablet in Postoperative Dental Pain (NCT03224403), a randomized phase 3 study. The primary outcome is Time to Confirmed Perceptible Pain Relief.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03224403 |
| Phase | Phase 3 |
| Condition | Post-operative Dental Pain |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 664 |
| Arms in the primary outcome | 4 |
| Lead sponsor | Johnson & Johnson Consumer Inc., McNeil Consumer Healthcare Division |
| Results posted | Yes |
2. Clinical Question
Population
Participants with postoperative dental pain following third-molar extractions were studied. The primary analysis population was the Intent-to-Treat population, defined in the registry record as all randomized participants. The record lists enrollment of 664, but that enrollment figure should not be treated as the number analyzed for every endpoint: the primary endpoint reports different group sizes, and the registry does not explain all differences between enrollment and endpoint data.
Intervention
The test treatment was a single 1000 mg dose of acetaminophen, given as two Test Acetaminophen 500 mg tablets. The study evaluated analgesic onset, efficacy, and safety. The primary endpoint measured the time from taking study medication until the participant reported perceptible pain relief that was subsequently confirmed by meaningful pain relief.
Comparator
The four parallel groups received test acetaminophen 1000 mg, commercial acetaminophen 1000 mg, commercial ibuprofen 400 mg, or placebo. The registry reports comparisons of each active group with placebo for the primary endpoint, as well as comparisons of test acetaminophen with the two active comparators. The record identifies the placebo group as the control for the posted primary results.
Primary question
Within 4 hours, how long did it take for participants to achieve confirmed perceptible pain relief, and how did the reported time-to-relief results compare across the randomized groups? The endpoint is about the timing of reported relief, not just whether relief was reported at a single scheduled time. The registry’s analysis describes the endpoint using medians and full ranges and reports statistical tests for selected group comparisons.
3. Trial Design
This was a randomized, quadruple-masked, parallel-group, phase 3 study of a single dose in a postoperative dental pain model. Participants had pain following third-molar extractions. The registry describes four assigned treatments: Test Acetaminophen 1000 mg, commercial acetaminophen 1000 mg, commercial ibuprofen 400 mg, and placebo. The test and commercial acetaminophen treatments were each given as two 500 mg tablets or caplets, while the ibuprofen treatment was given as two 200 mg liquid-filled capsules.
The registry lists enrollment of 664 and identifies the study as completed. The recorded study start was 2017-07-19, and the primary completion date was 2018-04-04. Those dates describe the trial record and do not establish when results became available or when analyses were performed.
Randomization supports comparisons between assigned groups, but the registry excerpt does not report the allocation ratio, details of sequence generation, or how allocation was concealed. Quadruple masking indicates that the registry labels the study as masked at four levels; the identities of those roles and the procedures used to maintain masking are not reported in the registry record. The record also does not describe rescue-medication rules or other co-interventions.
The primary endpoint analysis is identified as Intent-to-Treat and includes all randomized participants by definition in the registry description. The group sizes reported for the primary endpoint are 59 for placebo, 249 for Test ACM 1000 mg, 232 for commercial ACM 1000 mg, and 124 for commercial IBU 400 mg. The reasons these endpoint group sizes do not match the enrollment figure are not reported in the registry record. Endpoint-level availability and handling of participants without an observed event are also not described in the 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.
Overall Study
| Stage | Placebo | Test ACM 1000 mg | Commercial ACM 1000 mg | Commercial IBU 400 mg |
|---|---|---|---|---|
| STARTED | 59 | 249 | 232 | 124 |
| COMPLETED | 59 | 249 | 232 | 124 |
| NOT COMPLETED | 0 | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Analysis is based on the Intent-to-Treat (ITT) population, which included all participants who were randomized.
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.
| Characteristic | Unit | Placebo | Test ACM 1000 mg | Commercial ACM 1000 mg | Commercial IBU 400 mg | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 59 | 249 | 232 | 124 | 664 | |
| Age, Continuous | years | 18.3 (SD 1.91) | 19.0 (SD 2.31) | 18.9 (SD 2.17) | 19.2 (SD 2.56) | 18.9 (SD 2.28) |
| Sex: Female, Male: Female | Participants | 34 | 139 | 124 | 65 | 362 |
| Sex: Female, Male: Male | Participants | 25 | 110 | 108 | 59 | 302 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 1 | 1 | 1 | 1 | 4 |
| Race (NIH/OMB): Asian | Participants | 0 | 3 | 3 | 5 | 11 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 6 | 4 | 2 | 12 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 3 | 2 | 1 | 7 |
| Race (NIH/OMB): White | Participants | 55 | 229 | 215 | 108 | 607 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 2 | 7 | 7 | 7 | 23 |
| Region of Enrollment: United States | Participants | 59 | 249 | 232 | 124 | 664 |
6. Primary Endpoint
The registry lists the primary outcome as Time to Confirmed Perceptible Pain Relief, measured over within 4 hours.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Full Range |
| Unit | minutes |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was time to confirmed perceptible pain relief, measured in minutes within 4 hours after the participant took study medication. Participants started a stopwatch after taking the medication and stopped it when they first began to feel any pain relief. That initial report counted as confirmed perceptible relief only if the participant also stopped a second stopwatch to indicate meaningful pain relief. The endpoint therefore combines the timing of first perceptible relief with a confirmation based on meaningful relief.
Time-to-event outcomes preserve information about when an event occurs, rather than reducing the outcome to a yes-or-no status at a single assessment time. They are useful when timing itself is important to the clinical question. A median provides a summary of the distribution of observed times, while a full range reports its smallest and largest values. Neither summary describes every participant’s experience or the shape of the entire distribution.
The registry reports medians and full ranges for the active groups, but the placebo median is not reported in the registry record. The posted placebo result includes a range only. For all groups, the recorded upper range is 240.0 minutes; the record does not explain how observations reaching the end of the four-hour assessment window were handled in the analysis. The endpoint definition and summary statistics therefore support interpretation of the recorded time-to-relief results, but do not provide a complete account of event timing or follow-up for every participant.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
For the primary endpoint, the registry reports median time to confirmed perceptible pain relief of 15.7 minutes for Test ACM 1000 mg, 20.2 minutes for commercial ACM 1000 mg, and 23.2 minutes for commercial IBU 400 mg. The reported full ranges were 2.2 to 240.0 minutes, 4.0 to 240.0 minutes, and 2.5 to 240.0 minutes, respectively. For placebo, the full range was 4.9 to 240.0 minutes; a median is not reported in the registry record. The absence of that placebo median prevents a direct numerical comparison of the reported group medians.
The registry reports Wilcoxon tests comparing each active group with placebo, with p < 0.001 for each comparison. It describes these as superiority analyses. These p-values are evidence against the test’s null hypothesis under the analysis used; they do not quantify the size of a treatment difference, establish the probability that a treatment is effective, or describe the precision of a difference in minutes. No confidence intervals for the primary comparisons are reported in the registry record.
For the active-treatment comparisons, the registry reports a bootstrap re-sampling analysis for Test ACM versus commercial ACM, with p = 0.035, and for Test ACM versus commercial IBU, with p < 0.001. The record classifies these as superiority comparisons. The reported p-values alone do not show the estimated difference in time or its uncertainty. The group medians are descriptive summaries, not substitutes for an estimated between-group contrast and confidence interval.
The broad ranges, each extending to 240.0 minutes, indicate that the observed times were not confined to a narrow interval. A median cannot show how many participants experienced early relief, late relief, or no confirmed relief during the assessment window. The record does not provide a full distribution, survival estimates, or detailed handling of participants who did not reach the endpoint within the window. The summaries should therefore be read as partial descriptions of the time-to-event data.
The registry also reports early-time secondary outcomes and other endpoint analyses. These address related but not identical questions. Their interpretation depends on the definition of each outcome, the analysis population, and the multiplicity approach, which is not reported in the registry record. Overall, the posted results describe statistically significant primary comparisons and differing observed median times among the active groups, while leaving important details about effect-size uncertainty and analysis procedures unspecified.
9. Statistical Methods Explained
Time to confirmed perceptible pain relief is a time-to-event outcome: the event is confirmation of perceptible relief, and the recorded value is elapsed time from taking the study medication. Such outcomes retain information about timing. They also require decisions about participants for whom the event is not observed during the specified follow-up window. The registry identifies the primary timeframe as within 4 hours but does not report in this record how observations without confirmed relief by the end of that window were incorporated.
What does a median convey?
A median is a measure of the center of a distribution. For an event-time outcome, it describes the time by which the central point of the observed event-time distribution is reached, subject to the analysis’s treatment of censoring and incomplete follow-up. It does not give the average time, the experience of every participant, or the probability of relief at a particular minute. The registry reports a median and full range for each active group. It does not report a placebo median, so a numerical median-to-median comparison with placebo cannot be made from this record.
A full range gives the endpoints of the reported observations. It does not show how observations are distributed between those endpoints. In this study, the reported ranges extend to 240.0 minutes. Because the assessment timeframe is within 4 hours, values at that limit need interpretation in light of the trial’s event and follow-up rules. Those rules are not reported in the registry record, so it would be inappropriate to assume whether such values represent an event at the limit, an event not observed by the limit, or a particular censoring convention.
Why use a Wilcoxon test?
The registry identifies the placebo comparisons for the primary endpoint as Wilcoxon tests from SAS PROC LIFETEST. In general, the Wilcoxon family of methods compares the distributions of outcomes between groups. In a time-to-event setting, a test implemented through survival-analysis software can account for event-time information and, depending on the method and data structure, censored observations. The registry does not specify the precise Wilcoxon weighting convention or provide enough detail to reconstruct the analysis. A p-value is a measure of how compatible the observed data are with a specified null model; it is not an effect-size estimate and does not indicate the magnitude or clinical importance of a difference.
The registry reports p < 0.001 for the comparisons of placebo with Test ACM, commercial ACM, and commercial IBU. It labels each comparison as superiority. The p-values do not supply a confidence interval for the time difference, and no such interval is reported for these primary comparisons. The result should therefore be distinguished from a statement about the estimated number of minutes separating groups, which cannot be read directly from the reported p-values.
What does the bootstrap comparison add?
For Test ACM compared with commercial ACM and commercial IBU, the registry reports a bootstrap re-sampling method. In general, bootstrap methods use repeated re-sampling of observed data to assess the variability of a statistic. Their interpretation depends on the statistic being re-sampled, the resampling unit, and the implementation. Those details and an estimated contrast with a confidence interval are not reported in the registry record. The reported p-values are 0.035 and < 0.001, respectively, and the comparisons are classified as superiority analyses. These results do not by themselves describe the size or precision of the differences.
How should the secondary re-calculations be read?
The posted early-time binary outcomes include percentages with confirmed perceptible relief by specified minutes. The accompanying unadjusted re-calculations use posted group counts and denominators to estimate risk differences and confidence intervals for selected comparisons. A risk difference is the difference between two event proportions, expressed on the probability scale. Its confidence interval describes a range of values compatible with the data under the calculation’s assumptions; it is not a guarantee that the true effect falls within that interval. These calculations are unadjusted and should not be treated as replacing the registry’s reported logistic regression analyses.
The registry reports logistic regression for the early-time comparisons, with p < 0.001 for the listed outcomes. The registry excerpt does not give the model specification, covariates, or adjustment details. A difference between a simple unadjusted calculation and a regression result can arise because the analyses use different methods or assumptions. The reported figures should be interpreted according to their stated source and method, rather than treated as interchangeable estimates.
The sample-size illustrations attached to selected secondary results are planning calculations based on fractions of the observed effect. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They are illustrations for future planning, not observed power for this completed trial and not evidence that the trial was designed using those calculations. For binary outcomes, the illustrations are expressed as participants per arm. They do not account for every possible design choice or uncertainty in the observed effect.
General statistical interpretation also requires attention to the analysis population, missing data, multiplicity, and prespecified hypotheses. The registry identifies the primary population as Intent-to-Treat, but does not give endpoint-specific missing-data methods or a multiplicity strategy. These omissions limit assessment of how robust the reported significance tests are across all outcomes and comparisons.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Wilcoxon test from SAS PROC LIFETEST | not reported | < 0.001 | |
| Wilcoxon test from SAS PROC LIFETEST | not reported | < 0.001 | |
| Wilcoxon test from SAS PROC LIFETEST | not reported | < 0.001 | |
| bootstrap re-sampling method | not reported | 0.035 | |
| bootstrap re-sampling method | not reported | < 0.001 |
The registry’s primary results are sponsor-reported analyses: Wilcoxon tests from SAS PROC LIFETEST for comparisons with placebo and bootstrap re-sampling for the two listed comparisons of Test ACM with active treatments. Their reported p-values are the principal inferential results available for the primary endpoint. The registry does not report primary-comparison confidence intervals or estimated differences in time, so a recalculated effect estimate for those contrasts is not available in the record.
For selected early-time secondary outcomes, the posted results include simple unadjusted re-calculations alongside the registry’s reported logistic regression analyses. The re-calculations describe risk differences and confidence intervals based on the reported group counts and denominators. The registry’s regression p-values use a different analytical approach and are reported as p < 0.001 for the listed outcomes. These are related analyses, but they are not identical estimands or methods.
No discrepancy is flagged between the posted results and the re-calculations. That does not make the re-calculations a replacement for the sponsor’s analyses. The sponsor’s own analysis takes precedence if a discrepancy is identified; in the results available for this study, no such discrepancy is flagged. The re-calculations are best read as supplementary, unadjusted checks of selected secondary comparisons, with the sponsor-reported analyses remaining the registry’s stated inferential tests.
11. Multiplicity, Missing Data and Analysis Populations
The registry describes one primary endpoint and 21 posted secondary outcomes, and reports 30 analyses. Multiple outcomes and comparisons create a multiplicity issue: when many hypotheses are tested, the chance of obtaining at least one small p-value by chance can increase. This is a general statistical concern, not evidence that any particular reported result is false. A prespecified testing hierarchy or adjustment can help define how confirmatory results are interpreted, but the registry record does not report whether such a strategy was used.
The early-time secondary endpoints are particularly related because they assess confirmed perceptible relief at successive minute thresholds. Their results are not independent questions in the ordinary sense: the same participants and event histories can contribute across nearby thresholds. The registry reports logistic regression tests for the listed early-time outcomes, but the model details and any multiplicity adjustment are not reported in the registry record. The unadjusted re-calculations should accordingly be read as exploratory or descriptive support rather than as a family-wise confirmatory claim.
The primary analysis population is identified as Intent-to-Treat, including all randomized participants. That description does not establish that every randomized participant contributed an observed endpoint value or explain how incomplete observations were handled. The record does not report the number of participants with missing primary outcome data, the reasons for missingness, imputation procedures, censoring rules, or sensitivity analyses. It also does not explain the relationship between enrollment and the group sizes reported for the primary endpoint.
The registry lists outcome and analysis counts, but does not report whether the primary analysis was adjusted for baseline variables, whether analyses were prespecified in a statistical analysis plan, or how deviations from any plan were handled. Those details are important for assessing selective reporting and the strength of inferences across multiple tests. Their absence should be treated as an information limitation, not as proof that the methods were inadequate.
12. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Placebo | 1 | 59 | 1.7% |
| Test ACM 1000 mg | 1 | 249 | 0.4% |
| Commercial ACM 1000 mg | 0 | 232 | 0.0% |
| Commercial IBU 400 mg | 0 | 124 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Placebo | 0 of 59 |
| Test ACM 1000 mg | 0 of 249 |
| Commercial ACM 1000 mg | 0 of 232 |
| Commercial IBU 400 mg | 0 of 124 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Placebo | 9 of 59 |
| Test ACM 1000 mg | 13 of 249 |
| Commercial ACM 1000 mg | 16 of 232 |
| Commercial IBU 400 mg | 7 of 124 |
Most frequent serious adverse event terms
| Event term | Organ system | Placebo | Test ACM 1000 mg | Commercial ACM 1000 mg | Commercial IBU 400 mg |
|---|---|---|---|---|---|
| Pyelonephritis | Infections and infestations | 1 of 59 | 0 of 249 | 0 of 232 | 0 of 124 |
| Abortion Spontaneous | Pregnancy, puerperium and perinatal conditions | 0 of 59 | 1 of 249 | 0 of 232 | 0 of 124 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Placebo | Test ACM 1000 mg | Commercial ACM 1000 mg | Commercial IBU 400 mg |
|---|---|---|---|---|---|
| Nausea | Gastrointestinal disorders | 7 of 59 | 13 of 249 | 14 of 232 | 7 of 124 |
| Vomiting | Gastrointestinal disorders | 7 of 59 | 10 of 249 | 11 of 232 | 4 of 124 |
Serious events with the highest arm-level rate: pyelonephritis (1.7%), abortion spontaneous (0.4%).
The registry reports serious adverse events in the four groups as follows: placebo, 1; Test ACM 1000 mg, 1; commercial ACM 1000 mg, 0; and commercial IBU 400 mg, 0. It reports no deaths in any group. The at-risk group sizes listed for these safety summaries are 59, 249, 232, and 124, respectively. These figures describe the registry’s recorded serious adverse event counts; they do not establish whether an event was caused by study medication.
The record also lists other adverse event counts of 9 for placebo, 13 for Test ACM, 16 for commercial ACM, and 7 for commercial IBU. The definitions, severity breakdown, timing, and relationship assessments for these other events are not reported in the registry record. The listed serious-event terms include Pyelonephritis at 1.7% and Abortion Spontaneous at 0.4%, but the record excerpt does not identify which treatment group or groups those terms correspond to. Those percentages should not be assigned to a particular arm from the available information.
Safety counts in a trial of this design are descriptive. The record does not provide enough detail to compare event risks with precision or to determine causality. The absence of reported deaths is a statement about the posted record, not a guarantee that no other safety information exists outside it.
13. What the Result Does, and Does Not, Mean
The primary results show that the registry reported statistically significant time-to-event comparisons between each active group and placebo, with p < 0.001 for each. It also reported superiority comparisons of Test ACM with commercial ACM and commercial IBU. The active-group medians and reported ranges describe observed time-to-relief distributions, while the placebo median and primary contrast estimates with confidence intervals are not reported in the registry record.
A statistically significant test does not show how large a difference is, whether the difference is important to patients, or how likely a particular person is to experience relief. The primary p-values are not probabilities that the null hypothesis is true. Without an estimated contrast and its uncertainty, the strength of evidence about the magnitude of the time difference is difficult to assess from the primary results alone.
The findings concern a single-dose study in postoperative dental pain following third-molar extractions. They do not, by themselves, answer questions about repeated dosing, other pain settings, other populations, or longer-term outcomes. Nor do the posted efficacy results establish comparative safety beyond the event summaries reported in the registry.
The endpoint combines the participant’s report of first perceptible relief with confirmation through a second stopwatch indicating meaningful relief. It is therefore a participant-reported timing measure with a defined confirmation step, not an objective measurement of pain or a measure of pain elimination. The time-to-event summaries do not show each participant’s pain level, duration of relief, or later course.
Overall, the posted analyses support a statistical difference in the tested comparisons under the methods reported by the registry. They do not provide every quantity needed to judge the size, precision, clinical relevance, or generalizability of those differences. Missing details about multiplicity, incomplete outcomes, and the precise time-to-event analysis should remain part of the interpretation.
14. Why This Trial Matters Statistically
This trial illustrates why a clinical result should not be reduced to a single p-value. Its primary outcome is a time-to-event measure, and the registry reports both median times and full ranges. Those summaries answer different questions: a median describes a central point, while a range identifies the extent of recorded values without showing their distribution. The reported 240.0-minute upper limits also make the handling of the assessment-window boundary relevant, yet that handling is not described in the registry record.
The reported analyses use different methods for different comparisons. Wilcoxon tests from SAS PROC LIFETEST are reported for active treatments versus placebo, while bootstrap re-sampling is reported for comparisons of Test ACM with active comparators. The secondary early-time outcomes use logistic regression in the registry, with separate unadjusted re-calculations. Recognizing the distinction between methods prevents a simple re-calculation from being mistaken for the trial’s own analysis.
The study also demonstrates the interpretive challenge of multiple related outcomes. Repeated thresholds for relief can reveal timing patterns, but each additional test adds to the need for a clear analysis hierarchy and multiplicity plan. The registry record does not state how that issue was addressed. Likewise, identifying the Intent-to-Treat population is helpful, but it does not replace reporting of missing outcome data and the methods used to handle it.
Finally, the record makes clear that statistical significance and clinical interpretation are separate. The primary comparisons have reported p-values, but the record does not provide primary contrast estimates with confidence intervals. This limits assessment of effect size and precision. For clinical researchers and biostatisticians, the trial is a useful case for reading endpoint definitions, analysis methods, group summaries, and reporting gaps together rather than treating any one statistic as a complete account.
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 registry record leaves several trial-specific questions unanswered. It does not report the randomization ratio, the sequence-generation method, or the allocation-concealment procedures. It labels the study quadruple-masked but does not identify the masked roles or explain how masking was maintained. Details of rescue medication, concomitant treatment, and adherence are also not reported in the registry record.
The primary endpoint results do not include a placebo median or a confidence interval for any primary comparison. The record reports group medians and full ranges for the active treatments, but these summaries cannot reconstruct the full time-to-event distributions. It also does not explain how observations at the 240.0-minute limit or participants without confirmed relief during the four-hour window were handled. The statistical description names methods but does not give the full specifications needed to reproduce them.
Although the primary population is described as Intent-to-Treat, endpoint-specific missingness, reasons for missing data, and sensitivity analyses are not reported. The record’s enrollment figure and primary endpoint group sizes differ, and the reason for that difference is not stated. The registry also does not report a statistical analysis plan, prespecification details, or a multiplicity strategy for the many outcomes and analyses.
Safety summaries provide counts but little context on event timing, severity beyond the serious-event classification, relatedness, or follow-up. The listed serious-event terms are not assigned to treatment groups in the record excerpt. These limits constrain interpretation of both efficacy precision and comparative safety. They are limitations of the information available in the registry record and do not establish that the underlying trial lacked additional documentation.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Randomized, Double-Blind, Single-Dose, Efficacy and Safety Study of Test Acetaminophen Tablet in Postoperative Dental Pain — NCT03224403.
- Registry record last updated 2021-04-15; status last verified 2019-04.
- Results first posted 2021-04-15.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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19. Record Summary
NCT03224403 is a completed, randomized, quadruple-masked, parallel-group, phase 3, single-dose study in postoperative dental pain following third-molar extractions. The registry lists enrollment of 664 and compares Test Acetaminophen 1000 mg, commercial acetaminophen 1000 mg, commercial ibuprofen 400 mg, and placebo.
The primary endpoint was time to confirmed perceptible pain relief within 4 hours, analyzed in the Intent-to-Treat population. The registry reports active-versus-placebo Wilcoxon tests and active-treatment bootstrap comparisons, along with group medians and full ranges for the active groups. A placebo median and primary contrast confidence intervals are not reported in the registry record. Secondary outcomes include early-time relief measures, with selected re-calculations and registry-reported logistic regression results. Safety data include serious and other adverse event counts and no reported deaths.