Opioid Analgesic Reduction Study (OARS) - Pilot: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Opioid Analgesic Reduction Study (OARS) - Pilot (NCT05283499), a randomized phase 3 study. The primary outcome is Pain Level.

2. Clinical Question

The study’s stated purpose was to test protocols being developed for a future large, multisite trial comparing opioids with non-opioids for pain after impacted third-molar extraction. That purpose matters when reading the results: this registry record describes a pilot, and its findings can inform the description of outcomes and the uncertainty in this small study. It does not report whether the pilot was designed to establish a treatment effect.

The primary outcome is a patient-reported numerical rating of pain on the first day. The registry defines the scale from 0 for no pain to 10 for the worst pain imaginable. The main comparison is therefore between average reported scores, rather than a count of participants who crossed a pain threshold or achieved a specified response. The record does not report such a threshold or responder definition.

3. Trial Design

The registry identifies this as the Opioid Analgesic Reduction Study (OARS) - Pilot, a completed, randomized, parallel-group trial listed as Phase 3. The record describes quadruple masking. It does not explain which groups of people were masked, how masking was maintained, or how random assignment was generated. Those details are not reported in the registry record.

The study summary says its purpose was to test protocols being developed for a large multisite trial comparing opioid and non-opioid approaches to post-surgical impacted third-molar extraction pain. The registry lists an enrollment of 53. The primary and posted secondary outcome summaries give 25 participants in each arm. The record does not explain the difference between the enrollment figure and the outcome-summary group sizes, or provide a participant-flow account that would show whether all enrolled participants contributed to each measure.

The opioid arm is described as a combination analgesic of hydrocodone and acetaminophen; the non-opioid arm is described as a combination analgesic of ibuprofen and acetaminophen. The registry lists the interventions as drugs. It does not provide enough detail in the record to describe dosing schedules, duration of use, rescue medication, adherence, or other treatment procedures. No additional treatment arm is listed.

The primary outcome is average self-reported pain on the first day. Secondary outcomes listed in the record include sleep quality, pain interference and overall satisfaction, measured at the timeframes specified for each outcome. The record also lists 12 outcome measures, while the posted secondary summaries cover several distinct measures and repeated labels. The original statistical analysis plan, eligibility criteria, sample-size justification, and methods for handling incomplete outcome data are not reported in the registry record. The trial is marked completed, but that status does not fill in those methodological details.

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:

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 Level, measured over 1st day.

The primary endpoint is average pain reported by the participant on the first day. The registry describes a numerical rating scale from 0, meaning no pain, to 10, meaning the worst pain imaginable. The reported arm means are 5.67 for the opioid group and 4.09 for the non-opioid group. The mean difference, expressed as non-opioid minus opioid, is -1.58 points.

A patient-reported pain score directly captures the participant’s experience rather than an observer’s estimate. An average score provides a summary of the group’s reported pain level at the specified time. It does not show how scores were distributed among individuals, whether one participant’s score changed over time, or how many participants reached a particular level of pain. The registry does not report a threshold for a clinically important difference or a responder analysis.

As a general statistical point, a continuous score can retain information about differences across the scale, whereas dividing participants into response categories requires a threshold and can discard distinctions within categories. The record’s stated endpoint is a mean, so the posted comparison concerns the difference in group averages. That summary should be read together with its uncertainty: the reported confidence interval spans negative and positive values, and the unadjusted p-value is 0.058. The registry record does not describe the actual inferential model or specify a confidence level for the interval.

7. Results Posted in the Registry

• Non-Opioid: mean 4.09 versus 5.67 on control; difference -1.58 (95% CI -3.22 to 0.06), standardized effect d = -0.54; z-test p = 0.058.

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.

Sleep Quality

• 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 errors.
• Result:
  • Non-Opioid: mean 3.76 versus 5.45 on control; difference -1.69 (95% CI -3.62 to 0.24), standardized effect d = -0.49; z-test p = 0.086.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Non-Opioid and the control. The interval gives the range of effects that remain compatible with the data.

Pain Interference Scale (Patient Report Outcomes Measurement Information System - PROMIS 6b )

• 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 errors.
• Result:
  • Non-Opioid: mean 14.34 versus 17.62 on control; difference -3.28 (95% CI -6.79 to 0.23), standardized effect d = -0.52; z-test p = 0.067.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Non-Opioid and the control. The interval gives the range of effects that remain compatible with the data.

Overall Satisfaction

• Endpoint type: Continuous: a mean value per participant, compared as a difference in means.
• Test: Unadjusted two-sample z-test for the difference in means, using the posted standard deviations.
• Result:
  • Non-Opioid: mean 1.70 versus 2.10 on control; difference -0.40 (95% CI -1.05 to 0.25), standardized effect d = -0.34; z-test p = 0.228.
• Interpretation:
  • The 95% confidence interval includes no difference, so these data do not show a statistically significant difference between Non-Opioid and the control. The interval gives the range of effects that remain compatible with the data.

The posted secondary summaries cover sleep quality, pain interference and overall satisfaction. Their estimated mean contrasts are numerically lower in the non-opioid group, following the same numerical direction as the primary pain-score contrast. The intervals for these comparisons include zero, and the posted p-values are unadjusted. Taken together, the secondary summaries do not sharply distinguish between the arms in this pilot.

That shared numerical direction should be interpreted cautiously. The record does not provide scale anchors or scoring direction for all secondary measures, so a lower numerical score cannot automatically be described as better or worse across every outcome. The outcomes also concern different experiences and timeframes; they are not interchangeable measures of the primary first-day pain endpoint. Their relationship to the primary result is contextual rather than a direct replication of the same measure.

As a general statistical issue, testing multiple outcomes creates more opportunities for apparently notable results by chance. An unadjusted p-value addresses an individual comparison under its analysis assumptions; it does not account for a family of tests. The registry record does not report a multiplicity adjustment or identify a hierarchy that would distinguish confirmatory secondary outcomes from exploratory ones. Accordingly, the secondary findings carry less evidential weight than a clearly pre-specified primary analysis and should be treated as descriptive support for future questions, not as independent confirmation of a treatment effect.

The record lists repeated secondary outcome labels and does not explain the relationship between the listed measures and the posted summaries. It is also silent on whether analyses were planned at all listed timeframes or how missing measurements were handled. Those gaps make it difficult to assess the completeness and selection of the secondary results. The overall pattern can be noted, but the registry record does not support a claim that the secondary outcomes establish a consistent, clinically meaningful advantage.

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

• Sleep Quality
• Sleep Quality
• Sleep Quality
• Sleep Quality
• Pain Interference Scale (Patient Report Outcomes Measurement Information System - PROMIS 6b )
• Pain Interference Scale (Patient Report Outcomes Measurement Information System - PROMIS 6b )
• Pain Interference Scale (Patient Report Outcomes Measurement Information System - PROMIS 6b )
• Pain Interference Scale (Patient Report Outcomes Measurement Information System - PROMIS 6b )

9. Statistical Interpretation

10. Statistical Methods Explained

What does a mean difference represent?

The primary endpoint is continuous: each participant reports a score on a numerical scale, and the registry posts a mean for each arm. A mean difference is the contrast between those group averages. The listed contrast is for non-opioid minus opioid, so the negative estimate of -1.58 indicates a lower numerical mean in the non-opioid arm. This sign describes the direction of the score contrast; it does not establish a meaningful benefit or explain how every participant experienced pain.

As a general statistical concept, a group mean compresses a set of individual observations into one summary. It is useful for comparing average levels, but it does not show the spread of individual scores, skewness, clustering, or whether a small number of observations strongly influence the average. Individual participant data and distribution summaries are not reported in the registry record.

What is a standard error?

The primary pain summaries report standard errors. In general, a standard error describes the uncertainty of an estimated mean, rather than the spread of individual participant values. A smaller standard error usually indicates a more precisely estimated mean, given the assumptions behind the calculation. It should not be read as if most participants’ scores lie within one standard error of the mean. The standard errors for the primary means are 0.59 in each arm.

A standard deviation answers a different question: it describes variation among observations. Some secondary outcomes are reported with standard errors and another is reported with standard deviations. Those quantities are not interchangeable. The record does not report the underlying individual observations, and it does not explain the calculation details for every posted summary.

How should the confidence interval be understood?

In general, a confidence interval describes a range of values compatible with the observed data and the method used to construct the interval. It communicates uncertainty around an estimate more directly than a point estimate alone. The primary interval crosses zero: its lower endpoint is -3.215 and its upper endpoint is positive. Zero represents no mean difference. That interval therefore includes no difference and also permits differences in either direction within its bounds.

The registry does not state the confidence level, the interval method, or the model used for the primary comparison. It is therefore appropriate to describe the interval’s direction and whether it includes zero, but not to infer additional design details. A confidence interval is not a range containing a fixed proportion of individual pain scores; it concerns uncertainty about the estimated contrast under the method used.

What does the p-value add?

The posted primary p-value is 0.058 and is labeled unadjusted. In general, a p-value describes how unusual data at least as discrepant as those observed would be under a specified null model and its assumptions. It is not the probability that there is no treatment difference, and it does not measure the size or clinical importance of an effect. The registry does not report the test or model producing this value, so its interpretation should remain tied to the posted summary.

A p-value and confidence interval offer related but different information. The p-value summarizes compatibility with a null hypothesis under an analysis, while the interval shows a range of effect estimates consistent with the data and interval method. In this result, the interval includes zero and the p-value is close to, but greater than, 0.05. The planning calculations use a two-sided significance level of 0.05, but that planning assumption does not establish that the trial’s original analysis used the same threshold.

What are the limits of the reported comparisons?

The registry presents group means, standard errors or standard deviations, mean differences, confidence intervals, and unadjusted p-values for the posted comparisons. It does not report a statistical analysis plan, a named model, covariate adjustment, or a method for handling repeated observations. The registry also reports no analysis entries, although summary comparisons are posted. The record does not explain this distinction. It is therefore not possible to characterize the posted results as adjusted, model-based, or based on a particular analysis population.

As a general point, random assignment can support a causal comparison when the trial is conducted and analyzed according to an appropriate design. The registry identifies the study as randomized, but does not describe sequence generation, allocation concealment, adherence, crossover, or analysis by assigned group. A trial label alone does not supply those implementation details. Likewise, quadruple masking is listed, but the record does not identify who was masked or how masking was assessed.

The primary endpoint is one measure at one stated timeframe. The secondary outcomes cover other experiences and timeframes, but their analysis details and any multiplicity strategy are not reported. A nominal, unadjusted p-value for one of several outcomes does not account for the possibility of chance findings across multiple comparisons. The distinction between pre-specified confirmatory testing and exploratory summaries cannot be established from the registry record.

Why does over-dispersion matter in general?

Over-dispersion is a general concern when observed variation exceeds what a statistical model assumes. If a model underestimates variation, standard errors can be too small and confidence intervals too narrow, making evidence appear more precise than it is. If a model accounts for variation appropriately, uncertainty estimates better reflect the data structure. This is a general statistical principle, not a claim that over-dispersion occurred in this trial. The registry record does not report diagnostics or a model that would allow that question to be assessed.

For continuous outcomes, differences in scale properties, skewed distributions, outliers, and unequal variability can also affect the usefulness of simple mean-based summaries. The registry provides summary statistics but not enough distributional information to evaluate those features. Nothing in the posted values alone establishes that a particular assumption failed or held.

The published planning illustrations use a normal approximation and equal allocation as stated assumptions. Those are assumptions for the illustrations, not reported details of the original trial analysis. The sample-size estimates should consequently be read as planning scenarios rather than as evidence about the precision or power achieved by the completed pilot.

11. Confidence Intervals and Precision

The primary mean difference is -1.58 points, comparing the non-opioid arm with the opioid arm. The confidence interval’s lower endpoint is -3.215 and the upper endpoint is positive. Because the interval spans zero, the posted data are compatible with no mean difference as well as with contrasts on either side of zero under the interval method. The interval is wide enough that the exact size and direction of the underlying difference remain uncertain.

As a general explanation, a confidence interval communicates precision by showing how broadly the data support plausible estimates under a statistical method. It is not a prediction interval for individual participants, and it does not guarantee that the true value lies in the interval. The registry record does not report the confidence level or construction method, so those aspects of the interval cannot be independently described from the record.

The standard error for the mean is 0.59 in each arm. A standard error is about the precision of an estimated mean, not the degree of variation among participants. The posted interval for the difference conveys uncertainty in the contrast itself and is the more direct summary for assessing precision of the between-arm estimate.

The unadjusted p-value is 0.058. It should be read alongside the point estimate and interval, not as a substitute for either. The record does not report a pre-specified clinically meaningful threshold, so the interval cannot be judged against such a threshold. It also does not report the original sample-size justification or target precision. In this pilot, the result supplies an estimate with substantial uncertainty, rather than a precise resolution of the comparison.

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, not the original trial’s design justification. Because the outcomes are continuous, the figures are participants per arm, not total events. The stated planning assumptions are a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. Each scenario considers an effect equal to the stated fraction of the observed effect.

The 80% power column gives the planned number of participants per arm for a design that would have an 80% chance of detecting the specified effect under those assumptions, if that effect were the true one. The 90% power column gives the corresponding number for a design with a 90% chance under the same assumptions. Power describes the operating properties of a proposed study under a specified effect and model; it is not the chance that a particular result is true.

The rows use 100%, 75% and 50% of the observed effect. Across the planning scenarios, a smaller effect requires more participants per arm to maintain the same power. This reflects a general statistical principle: smaller differences are harder to distinguish from sampling variation unless the design obtains more information, for example through a larger sample.

These estimates are not observed power for the completed study. They are illustrations based on the observed effect and the listed assumptions. The trial’s own original sample-size assumptions and justification are not reported in the registry record. The figures should not be treated as proof that the pilot was adequately or inadequately sized for its stated purpose, nor as a substitute for a design calculation based on a pre-specified clinically meaningful effect.

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 = -1.580; pooled standard deviation σ = 2.950.
2. n = 2 × (1.96 + 0.842)² × 2.950² / -1.580² = 54.7, rounded up to 55 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 <- -1.58                      # observed difference in means
sigma <- 2.95                     # 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(5283499)
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 = 55 (80% power), 74 (90% power)
 75% of observed effect: n per arm = 98 (80% power), 131 (90% power)
 50% of observed effect: n per arm = 219 (80% power), 294 (90% power)
power.t.test: 55.7 
Simulated power at n = 55 per arm: 0.796 (20000 replicates)

The simulation draws many sets of group means and variances at the planned sample size and counts how often the two-sample t-test rejects the null. It should land close to the target power; at very small required sample sizes it can fall below it, because the normal approximation is rough there.

14. Multiplicity, Missing Data and Analysis Populations

The registry identifies a primary pain endpoint and lists several secondary outcomes, including repeated entries for sleep quality and pain interference. It also lists 12 outcome measures. The record does not report a multiplicity plan, a hierarchy of hypotheses, or any adjustment to account for testing multiple outcomes. The posted p-values for the comparisons are unadjusted. As a general principle, when several hypotheses are examined, the chance of at least one apparently unusual result can increase unless the analysis plan accounts for the collection of tests. Without the original plan, the intended role of each secondary result is not known.

The registry reports no analysis entries, while posting summary comparisons for the primary and secondary outcomes. The record does not explain why no analysis entries are listed or how the posted comparisons relate to an analysis plan. This does not establish that no analyses occurred; it means the registry record does not describe them in that field. The particular statistical tests, models, confidence level, handling of repeated measures and any covariate adjustments are not reported.

Missing-data methods are not reported in the registry record. The record does not provide participant flow by outcome, reasons for missing measurements, imputation methods, or sensitivity analyses. Enrollment is listed as 53, while the arm-level outcome summaries show 25 participants per arm. The registry does not reconcile those figures or say whether the summaries use all randomized participants, participants with available measurements, or another analysis population.

The record also does not state whether results were analyzed according to randomized assignment, treatment received, or another population definition. This matters because exclusions, incomplete reporting and deviations from assigned treatment can affect a group comparison. No conclusion about the presence or absence of bias from missing data can be drawn from the summary alone. The original statistical analysis plan and the procedures used to resolve these issues are not reported in the registry record.

15. 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 non-serious adverse event terms

The safety summaries list 25 participants at risk for serious adverse events in each arm. The number recorded as affected by a serious adverse event is 0 in the opioid group and 0 in the non-opioid group. Deaths are listed as 0 in both groups. No serious adverse-event terms are listed.

For other adverse events, the record lists 1 affected participant among 25 at risk in the opioid group and 0 among 25 at risk in the non-opioid group. The record does not describe the event, its severity, timing, relationship to treatment, or the method used to collect adverse events. It also does not provide further detail about event counts beyond the affected-participant summaries.

These are descriptive counts from a small pilot, not precise comparative safety estimates. As a general statistical point, observing no serious events in a study does not establish that the risk is absent; a study with limited observation can fail to capture uncommon events. The registry summaries do not support a broad conclusion about relative safety or the frequency of adverse events beyond the recorded figures.

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

The primary result is an estimated mean difference of -1.58 points in first-day self-reported pain, with a lower posted average in the non-opioid group. The confidence interval includes zero and reaches values in both directions. The unadjusted p-value is 0.058. Together, these summaries describe an uncertain estimate rather than a clear separation between the arms.

As a general interpretation, failure to exclude zero with a confidence interval is not proof that the groups are identical. Likewise, a p-value above a conventional threshold does not establish that there is no difference. The results are compatible with a range of possible contrasts, and the registry does not report a clinically meaningful threshold for deciding whether any particular contrast matters to participants. The data therefore cannot establish equivalence or non-inferiority, which require an appropriate design and pre-specified margins not reported in this record.

The trial is described as a pilot to test protocols for a future large multisite trial. Its role in that development effort is distinct from demonstrating a definitive treatment effect. The posted results can provide observed outcome summaries and an estimate of uncertainty, but the registry does not report whether the trial’s design or analysis was intended to make a confirmatory comparison.

The secondary summaries offer additional context, but they are unadjusted, their scale direction is not fully explained, and no multiplicity strategy is reported. The safety summaries record no serious adverse events or deaths in either arm and one other adverse event in the opioid group. Those counts do not establish that serious harms cannot occur or precisely compare safety between regimens.

These findings should not be used as medical advice or as a stand-alone basis for choosing treatment. The registry record does not supply the design details, full analysis plan, participant flow, missing-data methods, or event descriptions needed for a complete evaluation. The appropriate statistical conclusion is limited: the pilot’s posted means favor a lower numerical pain score in the non-opioid arm, but the estimate is imprecise and does not resolve the comparison.

17. Why This Trial Matters Statistically

This trial is statistically interesting because it combines a pilot purpose with a registry listing of Phase 3. Its stated aim was to test protocols being developed for a large multisite comparison, while the posted outcome summaries contain 25 participants per arm. That setting illustrates why the label attached to a trial should be read alongside its purpose, enrollment and actual outcome summaries. The record does not report the rationale for its phase designation or its original sample-size justification.

The primary result also illustrates why a point estimate alone is insufficient. The mean difference is -1.58, but its interval crosses zero and the unadjusted p-value is 0.058. The estimate points in one numerical direction, while the uncertainty remains broad enough to include no difference and values in the opposite direction. Statistical reporting is most useful when readers consider the estimate, precision, outcome scale and study context together.

The secondary outcomes and safety summaries show another important distinction: descriptive counts and estimates can be informative without constituting strong comparative evidence. Multiple unadjusted outcomes create interpretive uncertainty, and the record does not report how multiplicity or missing data were addressed. Transparent analysis plans and participant-flow details would help readers understand how the results were selected and analyzed.

Finally, the registry’s sample-size illustrations are planning scenarios based on observed effects, not evidence of the pilot’s achieved power. They demonstrate generally how smaller target effects require more participants under stated planning assumptions. The trial’s own design assumptions are not reported. Distinguishing such planning illustrations from the original protocol helps prevent post hoc calculations from being mistaken for an a priori justification.

18. 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 limitations follow from what the registry does not report. Although the study is identified as randomized and quadruple masked, the record does not describe sequence generation, allocation concealment, who was masked, or how masking was maintained. The information available therefore does not permit a detailed assessment of those design features.

The registry enrollment is 53, while the posted outcome summaries list 25 participants per arm. No participant-flow account explains the relationship between these figures, and no outcome-specific analysis population is defined. Missing-data handling, exclusions, protocol deviations and sensitivity analyses are not reported. These gaps prevent assessment of whether the summaries represent all randomized participants or only those with available outcome data.

The original protocol and statistical analysis plan are not reported. The registry does not identify the inferential test or model, the confidence level, covariate adjustment, multiplicity strategy, or a threshold for a clinically meaningful difference. It also does not state the trial’s original sample-size assumptions. The posted planning illustrations cannot fill that gap because they are based on observed effects and separate stated assumptions.

Details of treatment implementation are limited. The record does not report dosing schedules, duration, adherence, rescue medication or related procedures. The secondary outcomes include repeated labels, and the record does not explain the mapping between those entries and the posted summaries. Scoring direction is not given for every secondary measure. Adverse-event summaries provide limited counts but not descriptions or collection methods.

These limitations do not prove that the trial was conducted improperly. They define what cannot be evaluated from the registry record and constrain the strength and scope of conclusions drawn from its posted summaries.

19. Related Tutorials

20. Related Statistical Calculators

21. Sources

• ClinicalTrials.gov: Opioid Analgesic Reduction Study (OARS) - Pilot — NCT05283499.
• Registry record last updated 2023-06-06; status last verified 2023-06.
• Results first posted 2022-07-13.
• 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.

22. Record Summary

The Opioid Analgesic Reduction Study (OARS) - Pilot is listed as a completed, randomized, parallel-group, quadruple-masked Phase 3 study sponsored by Rutgers, The State University of New Jersey. The registry gives an enrollment of 53 and describes the study as testing protocols for a future large multisite comparison of opioid and non-opioid approaches to post-surgical impacted third-molar pain.

The primary endpoint is average self-reported pain on the first day, rated from 0 to 10. The posted means are 5.67 for opioid and 4.09 for non-opioid; the reported mean difference is -1.58, with an interval that includes zero and an unadjusted p-value of 0.058. Secondary summaries cover sleep quality, pain interference and satisfaction. Safety summaries list no serious adverse events or deaths and one other adverse event in the opioid group.

The registry record does not report the original sample-size justification, detailed statistical analysis plan, missing-data methods, analysis population, or participant-flow reconciliation. Its planning illustrations are separate from the original trial design and should be read as scenarios, not observed power.