Ibuprofen Extended-Release Dental Pain Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Ibuprofen Extended-Release Dental Pain Study (NCT00707057), a randomized phase 3 study. The primary outcome is Analgesic Efficacy, as Measured by the Sum of Pain Intensity Differences (SPID) Scale.

2. Clinical Question

3. Trial Design

The registry record identifies NCT00707057 as a completed phase 3 randomized trial with a parallel-group design and quadruple masking. It studied ibuprofen 600 mg extended-release tablets and placebo in people with dental pain following third-molar extraction. The stated purpose was to evaluate efficacy and safety with multiple doses of the extended-release tablets. The sponsor was SCOLR Pharma, Inc. The recorded study start was 2008-06 and primary completion was 2008-10.

The arm descriptions specify planned random assignment of 160 subjects to ibuprofen and 80 to placebo. Assignment was described as based on gender and baseline pain intensity, rated on an 11-point numerical scale. The registry gives moderate pain as 5–7 and severe pain as 8–10. The posted primary outcome includes 169.0 participants in the ibuprofen group and 87.0 in the placebo group. The registry record does not explain the difference between the arm counts in the descriptions and the numbers contributing to the posted outcome.

The primary outcome population is stated to be intention to treat. The record does not report further details about how that population was defined or how participants with missing outcome data were handled. The trial lists 14 outcome measures and 21 analyses. It also lists secondary outcomes covering relief timing, pain relief and pain-intensity-difference scores, rescue medication, and evaluations after the first dose. The complete protocol, detailed conduct of masking, and the trial’s original sample-size justification 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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intention to treat (ITT)

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 Analgesic Efficacy, as Measured by the Sum of Pain Intensity Differences (SPID) Scale, measured over from baseline to 12 hours after dose 1.

The primary endpoint is the sum of pain-intensity differences (SPID) for the 8–12 hour measurement interval after dose 1. Pain intensity was recorded at baseline and at 8, 9, 10, 11, and 12 hours after the dose using an 11-point PI-NRS, ranging from 0, no pain, to 10, worst possible pain. The registry says the endpoint is based on a mean of the sum at the five assessed time points and gives the total scale range as 0 to 50. Participants selected the number that best described their pain at each observation.

SPID combines repeated pain-intensity assessments into a single outcome for the specified interval. As a general statistical concept, a repeated-measure summary can describe the pattern across several observations more compactly than a single time-point result. It also makes the timing and construction of the endpoint important: the primary result concerns the interval after the first dose, not every later dose or every secondary pain measure in the trial.

The registry labels the measure as analgesic efficacy and reports means and standard deviations. The posted group means are 14.8 for ibuprofen and 0.4 for placebo. The registry record does not give additional detail about the calculation convention for pain-intensity differences beyond the description above. Interpretation should therefore stay close to the defined score and the reported comparison rather than treating the score as a direct measure of every aspect of pain or relief.

7. Results Posted in the Registry

• Ibuprofen 600mg ER: mean 14.80 versus 0.40 on control; difference 14.40 (95% CI 10.89 to 17.91), standardized effect d = 0.96; z-test p = <0.001.

8. Secondary Efficacy Endpoints

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

Percentage (%) of Subjects With Confirmed First Perceptible Relief Within 1 Hour of Dose 1

• Endpoint type: Binary: the percentage of participants with the event (counts rebuilt from the posted percentages and group sizes).
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Ibuprofen 600mg ER: 62.1% (105/169) versus 11.5% (10/87) on control; risk difference 50.6 percentage points (95% CI 40.7 to 60.6), risk ratio 5.41 (2.98–9.80); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Ibuprofen 600mg ER than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Percentage of Subjects Achieving "Meaningful" Relief as Indicated by the Time Recorded on the Second Stopwatch Following "First Perceptible" Relief

• Endpoint type: Binary: the percentage of participants with the event (counts rebuilt from the posted percentages and group sizes).
• Test: Unadjusted two-proportion z-test, with a Wald 95% confidence interval for the risk difference.
• Result:
  • Ibuprofen 600mg ER: 69.2% (117/169) versus 17.2% (15/87) on control; risk difference 52.0 percentage points (95% CI 41.4 to 62.5), risk ratio 4.02 (2.51–6.43); unadjusted two-proportion z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the proportion with the event is statistically higher for Ibuprofen 600mg ER than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

Global Evaluation for Dose 1

• 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:
  • Ibuprofen 600mg ER: mean 6.05 versus 1.79 on control; difference 4.26 (95% CI 3.45 to 5.07), standardized effect d = 1.28; z-test p = <0.001.
• Interpretation:
  • The 95% confidence interval excludes no difference, so the mean is statistically higher for Ibuprofen 600mg ER than for the control. This is an unadjusted, secondary comparison, so it is suggestive rather than confirmatory.

The numerical secondary results described in the registry show higher recorded values in the ibuprofen group for the two relief-percentage outcomes and for the global evaluation score. The relief outcomes concern confirmed first perceptible relief within 1 hour and meaningful relief within 4 hours; the global evaluation was recorded at 12 hours after dose 1 or at the time of rescue. These endpoints capture different aspects of the post-dose experience from the primary SPID measure.

The direction of the posted group summaries is broadly consistent in the limited sense that the ibuprofen group has higher recorded values on these reported measures, as it does on the primary mean SPID score. That numerical pattern does not establish that the measures represent the same construct, nor does it show that one endpoint validates another. Each outcome has its own definition, analysis, and uncertainty. The registry lists 12 posted secondary outcomes, while the detailed numerical results described in the record are not complete for every listed outcome.

Secondary outcomes can help describe other dimensions of the trial, including timing of relief, scores across intervals, and use of rescue medication. They are not a replacement for the prespecified primary outcome. The registry reports methods and p-values for some secondary comparisons, but it does not report whether multiplicity was controlled across the full set of analyses. When many outcomes are tested, nominal or unadjusted results carry less weight because the chance of finding a seemingly notable result can rise across the set. Interpretation should give priority to the primary comparison and treat secondary findings as supporting context rather than standalone confirmation.

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

• Time to Confirmed "First Perceptible" Relief
• Time to Confirmed "Meaningful" Relief
• Percentage (%) of Subjects With Confirmed First Perceptible Relief Within 1 Hour of Dose 1
• Percentage of Subjects Achieving "Meaningful" Relief as Indicated by the Time Recorded on the Second Stopwatch Following "First Perceptible" Relief
• Analgesic Efficacy for the 0-12, 0-4, 4-8, and 4-12 Hour Dosing Intervals After Dose 1 Using Total Pain Relief (TOTPAR) and Sum of Pain Intensity Difference(SPID)
• Duration of Relief After Dose 1
• Percentage of Participants Who Require Rescue Medication at or Prior to Hour 8, Hour 10, and Hour 12 After Taking Dose 1
• Pain Relief and PID Scores at Individual Time Points for Dose 1

9. Statistical Interpretation

10. Statistical Methods Explained

The primary outcome is continuous: each participant contributes a numerical SPID score, and the registry reports a group mean and standard deviation. A mean describes the group’s average score; a standard deviation describes the spread of participant scores around that average. The posted values are means of 14.8 and 0.4, with standard deviations of 16.33 and 11.93, for the ibuprofen and placebo groups respectively. These summaries do not show the distribution of individual responses or how many participants had scores in any particular range.

What does the reported ANCOVA contribute?

The registry identifies analysis of covariance (ANCOVA) as the sponsor’s method for the primary comparison. In general, ANCOVA compares group outcomes while accounting for specified covariates. Adjustment can improve precision or change the comparison when covariates relate to the outcome. The registry does not report which covariates were included, the model specification, or the adjusted group estimates. The reported p-value is < 0.001. Without the adjusted estimate and its confidence limits, the magnitude and precision of the sponsor’s adjusted comparison cannot be read directly from that p-value.

The simple recalculation uses the posted group summary statistics to estimate an unadjusted difference in means. It gives 14.4, with a 95% confidence interval from 10.89 to 17.91 and p < 0.001. This is not the ANCOVA result and does not reproduce any adjustment for baseline factors or other covariates. It is useful as a check on the scale and broad contrast in the posted summaries, but the sponsor’s reported analysis remains the trial’s own analysis.

How should the p-values be read?

A p-value describes how unusual data at least as incompatible with a specified null hypothesis would be under the statistical model and assumptions used for the test. It is not the probability that the null hypothesis is true, and it does not measure the size of an effect. The sponsor-reported primary p-value, < 0.001, and the unadjusted recalculated p-value, < 0.001, come from different analyses. Their thresholds should be read with the method attached to each result rather than as interchangeable estimates.

For secondary outcomes, the registry reports Cochran-Mantel-Haenszel analyses for the categorical relief measures and ANCOVA for the global evaluation measure. In general, the Cochran-Mantel-Haenszel method can compare categorical outcomes while accounting for strata. The registry does not specify the strata or other details of those models. ANCOVA is a covariate-adjusted approach for a continuous outcome, but the adjustment details for the secondary global evaluation are also not reported in the registry record.

Why do repeated observations and distributions matter?

The primary endpoint condenses observations at five time points into a summary score. This can make the comparison easier to interpret as one interval-level outcome, but it also means that the result does not separately describe each time point. The registry includes pain measures at individual times among the secondary outcomes, but the detailed results for all such measurements are not reported in the registry record. The standard deviations indicate appreciable variation in scores, but the registry’s summary statistics alone do not show whether the distributions are symmetric, contain outliers, or differ in shape.

General statistical methods may rely on assumptions about model form and error distributions. Over-dispersion, in general, means that observed variability is greater than a model expects; if present and unaccounted for, standard errors and inference may be unreliable. The posted primary summary does not itself establish whether over-dispersion occurred. The record does not describe diagnostic checks, transformations, robust methods, or other sensitivity analyses, so none can be assumed.

What can the posted analysis establish?

Randomization is the allocation method identified in the record, and the reported population for the primary outcome is ITT. In general, randomization supports a comparison of assigned groups by reducing systematic differences at allocation, while an intention-to-treat approach aims to retain participants in their assigned groups. The registry does not describe adherence, crossovers, exclusions, or the operational definition of ITT. Those details are needed to assess how closely the posted analysis followed the intended approach.

The registry’s analysis count is 21, and it lists 14 outcome measures. A number of tests across outcomes can increase the chance that at least one result appears statistically notable by chance. Whether and how the sponsor accounted for multiplicity is not reported in the registry record. Confidence intervals, model details, missing-data handling, and prespecified analysis documentation would add context to the reported tests. The registry’s reported p-values and descriptive summaries should therefore be interpreted as evidence about the posted comparisons, with uncertainty about unreported analytical choices.

11. Confidence Intervals and Precision

The primary simple, unadjusted recalculation estimates a mean difference of 14.4, with a 95% confidence interval from 10.89 to 17.91. A confidence interval expresses the uncertainty around an estimate under the assumptions of the method used. In general, a narrower interval indicates greater precision, while a wider interval allows a broader range of values compatible with the data and method. The interval is for the unadjusted recalculation, not the sponsor’s ANCOVA estimate.

The sponsor-reported primary result gives p < 0.001 but no adjusted effect estimate or confidence limits. A small p-value does not convey the width of an interval or the range of plausible effect sizes. The unadjusted interval gives a sense of precision for a different calculation; it cannot be assigned to the adjusted result. The registry record does not report the covariate-adjusted confidence interval.

The posted primary group summaries include 169.0 participants for ibuprofen and 87.0 for placebo. Standard deviations of 16.33 and 11.93 describe variability in the observed outcome scores, rather than uncertainty in the group means. The secondary binary outcomes have reported group percentages and 95% confidence intervals, and the recalculated comparisons have intervals for risk differences. Such intervals quantify uncertainty for their own outcomes and comparison methods; they do not resolve uncertainty about unreported outcomes or analysis choices.

Confidence intervals do not account automatically for every source of uncertainty. In general, they are conditional on the statistical model, the data included, and the method used to construct them. Missing-data handling, outcome measurement, model specification, and multiplicity can affect interpretation. Those details are not all reported in the registry record. Precision should therefore be judged alongside the endpoint definition, analysis population, and limits of the available reporting.

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 the observed effect, not the trial’s original design calculations. The displayed figures are participants per arm, rather than total events. The planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is the stated fraction of the observed effect. The registry’s original sample-size assumptions and justification are not reported in the registry record.

The 80% power column gives the illustrative number of participants per arm for a design with an 80% chance of detecting the specified effect under the listed assumptions, if that effect and the assumptions are correct. The 90% power column gives the corresponding illustration for a 90% chance. These are design calculations, not estimates of the probability that the completed trial’s result is correct.

The rows consider planning for 100%, 75%, and 50% of the observed effect. A smaller effect is harder to distinguish from random variation, so the illustration requires more participants per arm. The table and curve are best read as sensitivity analyses: they show how planning requirements change when the target effect differs from the observed estimate. Because the observed effect itself is uncertain and may not represent a future study, these values should not be treated as a universal sample-size recommendation.

This is not observed power. Observed power calculated from the trial’s estimated effect would largely restate the observed result and does not provide an independent measure of its reliability. The planning figures instead show hypothetical requirements under explicit assumptions. Time-to-event calculations, if included in the broader planning approach, are described as total events; that convention does not apply to the displayed participant-per-arm figures.

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 = 14.400; pooled standard deviation σ = 14.987.
2. n = 2 × (1.96 + 0.842)² × 14.987² / 14.400² = 17.0, rounded up to 18 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 <- 14.4                      # observed difference in means
sigma <- 14.9871283752762                     # 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(707057)
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 = 18 (80% power), 23 (90% power)
 75% of observed effect: n per arm = 31 (80% power), 41 (90% power)
 50% of observed effect: n per arm = 69 (80% power), 92 (90% power)
power.t.test: 18 
Simulated power at n = 18 per arm: 0.794 (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 sponsor’s primary analysis is reported as ANCOVA with p < 0.001. The posted registry record does not include its adjusted mean difference or confidence interval, and it does not specify the ANCOVA covariates. The sponsor analysis is therefore the reported trial analysis, but its magnitude and precision cannot be reconstructed from the registry entry alone.

The simple recalculation from the posted arm summaries yields an unadjusted mean difference of 14.4, a 95% confidence interval from 10.89 to 17.91, and p < 0.001. It does not adjust for covariates and is not a replication of ANCOVA. The two analyses address the same primary outcome but use different information and methods, so estimates and p-values should be presented with their respective labels.

The registry indicates no discrepancy flag for this comparison. That does not make the recalculation equivalent to the sponsor analysis or fill in the missing model details. The adjusted result should be identified as sponsor-reported, and the summary-statistic result as an unadjusted recalculation. Neither should be described as more informative than its reported content supports.

15. Multiplicity, Missing Data and Analysis Populations

The registry lists 14 outcome measures and 21 analyses. Multiple comparisons raise a general statistical concern: when many hypotheses are tested, the chance of at least one apparently unusual result under null conditions can increase. Methods such as prespecifying a hierarchy or adjusting significance thresholds can address that issue, but the registry record does not report whether a multiplicity strategy was planned or used. It is therefore not possible to determine from the posted record whether the reported secondary p-values account for the full family of outcomes and analyses.

The primary outcome is identified, and its reported population is intention to treat. The registry does not report a detailed statistical analysis plan, a protocol-based hierarchy for secondary outcomes, or the prespecification status of each analysis. It also does not provide details of the ANCOVA model or the strata used for Cochran-Mantel-Haenszel analyses. These omissions limit assessment of whether model choices followed a plan established before the results were known.

Missing-data handling is not reported in the registry record. The outcome counts are posted, but the record does not explain whether all randomized participants had endpoint data, how missing measurements were handled, whether any imputation was used, or whether sensitivity analyses were performed. The record also does not explain the relationship between the planned arm descriptions and the numbers contributing to the primary outcome. Without these details, the effect of missingness or exclusions on the results cannot be evaluated.

ITT is named as the primary outcome population, but the operational definition and analysis procedures are not specified. Information about treatment adherence, withdrawals, rescue medication in relation to outcome scoring, and handling of protocol deviations is not reported in the registry record. These are not grounds to assume a particular bias or analytical choice; they are limits on what can be assessed from the registry reporting.

16. Safety Results

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

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0.35% reporting threshold.

The posted adverse-event figures list zero participants affected by serious adverse events in the ibuprofen group and zero in the placebo group. The registry also lists zero affected by other adverse events in each group. The numbers at risk are 169 in the ibuprofen group and 87 in the placebo group for both categories. Death counts are not reported in the registry record.

These figures describe what was entered for the listed categories; they do not establish that no adverse events of any kind occurred or provide detail about event definitions, duration of observation, severity grading, or causal attribution. The registry gives no serious adverse-event terms in its posted list. A zero count in the registry should be read as a reported count for the specified record fields, not as a guarantee of absence of risk. The posted safety summary does not permit broader conclusions about safety beyond these recorded figures.

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

The registry reports a randomized comparison of ibuprofen 600 mg extended-release tablets and placebo for pain after third-molar extraction. For the primary SPID outcome, the posted mean was 14.8 in the ibuprofen group and 0.4 in the placebo group. The sponsor’s ANCOVA analysis reported p < 0.001. A simple unadjusted recalculation gives a mean difference of 14.4 with a 95% confidence interval from 10.89 to 17.91. These statements describe the recorded results and the methods attached to them; they do not by themselves establish the importance of the score difference to individual participants.

The result applies to the trial population, the recorded primary endpoint, and the interval after the first dose. The registry does not provide enough detail to extend the result to other pain conditions, other treatment regimens, other populations, or outcomes over longer periods. The secondary outcomes address additional experiences and measurements, but their completeness and multiplicity handling are not reported in the registry record.

A statistically significant test does not mean that every participant experienced the same outcome, nor does it quantify the certainty of every clinical interpretation. The group standard deviations indicate variability in scores, and the recalculated interval expresses uncertainty under its unadjusted method. The sponsor’s adjusted estimate and confidence interval are not posted, and details of missing-data handling and the analysis plan are absent.

The safety entries report zero affected participants for serious and other adverse-event categories in both groups, while deaths are not reported. These registry entries should not be read as proof that risk is absent. Overall, the record supports a specific statistical description of the posted comparison, while leaving important questions about model details, completeness of follow-up, safety reporting, and broader applicability unresolved.

18. Why This Trial Matters Statistically

This trial illustrates why endpoint definition and analysis method matter when interpreting a clinical comparison. The primary outcome is not a single pain rating, but an SPID summary built from observations at five time points during the 8–12 hour interval after the first dose. The mean difference therefore describes a constructed interval-level score. Readers need the scale, timing, and scoring description to understand what the comparison represents.

The record also provides an example of the distinction between a sponsor-reported adjusted analysis and a recalculation from posted group summaries. The ANCOVA p-value is reported, but its adjusted estimate and confidence interval are not. The unadjusted recalculation supplies an estimate and interval, but it answers a simpler statistical comparison. Keeping those results separate prevents the apparent precision of one method from being attributed to another.

Finally, the trial highlights the limits of interpreting a registry record without a complete statistical plan. The record identifies an ITT population and analysis methods for selected outcomes, yet does not detail model covariates, missing-data procedures, or multiplicity handling. Those omissions matter because confidence intervals and p-values depend on the analysis choices and data included. Clear reporting of these choices would help readers assess both the size and reliability of the comparisons without having to infer methods that are not documented.

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.

Several trial-specific limits affect interpretation. The registry describes planned assignment of 160 subjects to ibuprofen and 80 to placebo, while the primary outcome summaries include 169.0 and 87.0 participants respectively. The record does not explain this difference. The primary measure is described as the mean of a sum across five observations, but further detail about the calculation of pain-intensity differences is not reported in the registry record.

The sponsor’s primary ANCOVA result is reported only as a p-value. The adjusted contrast, confidence limits, covariates, and model specification are not reported in the registry record. The unadjusted recalculation cannot fill those gaps. The record also does not describe missing-data procedures, adherence, withdrawals, sensitivity analyses, or the exact operational definition of the ITT population.

Although the record lists 14 outcome measures and 21 analyses, its approach to multiplicity is not reported. Detailed numerical results for every listed secondary outcome are not available in the record. The safety information is limited to the posted counts for serious and other adverse events; death counts are not reported. Event definitions, follow-up duration, and attribution are not posted in the registry record.

These limitations constrain what can be concluded from the registry entry. They do not establish that the analyses were inappropriate or that data were missing; they indicate that those aspects cannot be evaluated from the available reporting. Generalizability beyond the recorded setting and population is also not established by this trial record.

20. Related Tutorials

21. Related Statistical Calculators

22. Sources

• ClinicalTrials.gov: Ibuprofen Extended-Release Dental Pain Study — NCT00707057.
• Registry record last updated 2011-03-24; status last verified 2011-03.
• Results first posted 2011-03-23.
• 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

NCT00707057 is a completed randomized, quadruple-masked, parallel-group phase 3 trial of ibuprofen 600 mg extended-release tablets versus placebo for post-operative pain after third-molar extraction. The primary outcome was SPID over the 8–12 hour interval after dose 1 in the ITT population. The posted means were 14.8 and 0.4, respectively; the sponsor-reported ANCOVA result was p < 0.001.

A simple unadjusted recalculation gives a mean difference of 14.4, with a 95% confidence interval from 10.89 to 17.91. The registry also posts selected secondary results and adverse-event counts, while important details about model specification, missing data, multiplicity, and the trial’s original sample-size justification are not reported in the registry record.