Postoperative Pain Control in Septum and Sinus Surgery: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Postoperative Pain Control in Septum and Sinus Surgery (NCT04149964), a randomized phase 4 study. The primary outcome is Number of Doses of Opiate (Narcotic) Pain Medication.

2. Clinical Question

The comparison concerns two medication regimens, not acetaminophen scheduling in isolation: the arms also differ in the specified as-needed opiate medication. The registry describes participants as randomized like a flip of a coin. It does not report a blinding procedure, and masking is recorded as none.

The primary outcome is reported as a median and inter-quartile range for each arm. Those summaries describe the observed distributions among participants with available outcome data; they do not, by themselves, establish whether a between-arm difference is statistically reliable. A formal primary comparison or its uncertainty is not reported in the registry record. The clinical question is therefore narrower than a definitive claim about comparative benefit: what do the posted outcome summaries show, and how much uncertainty and missing information must be considered when reading them?

3. Trial Design

The registry describes a phase 4, randomized, parallel-group study with no masking. Its title is “Postoperative Pain Control in Septum and Sinus Surgery,” and the listed sponsor is Corewell Health East. The study is recorded as completed. The registry gives a start date of 2019-11-27 and a primary completion date of 2022-09-21.

The two arms use different postoperative pain regimens. In the standard-of-care arm, acetaminophen is taken as needed, with acetaminophen/hydrocodone available as needed for pain. In the study arm, acetaminophen is scheduled every 6 hours, while oxycodone is available as needed for breakthrough pain. Random allocation supports a planned comparison between assigned regimens, but the registry record does not report details about sequence generation, allocation concealment, adherence, or whether the analysis followed assigned treatment.

The enrollment figure is 65. The primary outcome description says that data were unavailable for patients lost to follow-up who did not complete the postoperative questionnaire, and reports 19 patients lost in the standard-of-care arm and 18 in the study arm. The arm-level primary summaries are based on 15.0 and 13.0 participants, respectively. The record does not explain how these available outcome counts relate to every enrolled participant beyond the stated loss to follow-up.

The registry lists a seven-day timeframe for the primary endpoint and several secondary outcome topics, including pain scores and medication use. It records no reported analyses for the secondary outcomes. The record does not describe a sample-size justification, a prespecified statistical analysis plan, interim analyses, or methods for handling missing outcomes. Those omissions limit how fully the observed results can be placed in the context of the original trial plan.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: 65 patients were enrolled. Data is not available for patients lost to follow up who did not complete post-operative questionnaire. 19 patients in SOC arm and 18 in study arm were lost to follow up.

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.

Population: 65 patients were enrolled. Baseline data on sex is not available for patients lost to follow up who did not complete post-operative questionnaire. 19 patients in SOC arm and 18 in study arm were lost to follow up.

6. Primary Endpoint

The registry lists the primary outcome as Number of Doses of Opiate (Narcotic) Pain Medication, measured over 7 days.

The primary endpoint is the number of doses of opiate (narcotic) pain medication taken for breakthrough pain during the first postoperative week. Counting doses is a way to describe medication use over a defined period. It addresses a practical aspect of postoperative pain management: how often participants used the available opiate medication under their assigned regimen.

The registry summarizes this count with a median and inter-quartile range. A median describes the middle of the observed values when they are ordered. The inter-quartile range describes the middle half of the observed distribution, from its lower to upper quartile. These summaries are useful for count outcomes that may be unevenly distributed or include many low values. They do not describe every participant’s experience, and an inter-quartile range is not a confidence interval for the median or for the difference between arms.

The posted median was 1.0 dose in the standard-of-care arm, with an inter-quartile range of 0.0 to 4.5. In the study arm, the median was 1.5 doses, with an inter-quartile range of 0.0 to 6.0. These are descriptive summaries among the participants contributing outcome data. The registry does not report a primary between-arm estimate, confidence interval, or p-value, so the summaries do not quantify the precision of a treatment contrast.

This outcome captures use of the specified opiate medication, not pain intensity itself. A dose count alone cannot establish why participants used more or fewer doses, or whether their pain experience differed. The registry lists pain scores and other medication-use measures as secondary outcomes, but the primary count should be interpreted as one specific measure of postoperative medication use.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a median and inter-quartile range convey?

For the primary endpoint, the registry reports a median number of opiate doses and an inter-quartile range in each arm. The median is the central value after observations are ordered. The inter-quartile range runs from the lower quartile to the upper quartile and describes the span containing the middle half of observed values. These summaries can be informative when a count outcome is not well described by a symmetric distribution or when a small number of high values might pull a mean upward.

The standard-of-care arm has a median of 1.0 and an inter-quartile range of 0.0 to 4.5; the study arm has a median of 1.5 and an inter-quartile range of 0.0 to 6.0. Both inter-quartile ranges include zero and overlap. Their overlap does not constitute a formal test, and the ranges are not confidence intervals. They show the spread of observed values, not the uncertainty around the difference between the arms. The registry does not report a test or an interval estimate for the primary comparison.

Why does the primary comparison need more than arm summaries?

Separate arm medians describe each observed group but do not, by themselves, estimate the uncertainty in a between-arm contrast. A statistical comparison would need to specify an estimand and a method suitable for the endpoint and trial design. The registry record does not report the method used for a primary comparison, nor does it present a primary effect estimate, confidence interval, or p-value. The absence of those elements means the posted primary summaries cannot support a claim about statistical significance.

Counts of medication doses can have skewed distributions, ties, and a concentration of observations at low values. General statistical practice considers whether a method’s assumptions fit such data. Methods that rely on a normal approximation may not represent a highly uneven count distribution well, while rank-based or count-regression approaches make different assumptions and answer different questions. The registry does not state which method, if any, was planned or used for the primary endpoint, so a specific method should not be inferred.

How should the secondary binary comparisons be read?

Three secondary outcomes have posted arm counts and unadjusted comparisons. For these binary outcomes, a risk difference expresses the difference between the observed proportions in the study arm and the standard-of-care arm. The confidence interval gives a range of effect values compatible with the data under the method used; it represents statistical uncertainty, not a range containing a guaranteed proportion of future results. If a risk-difference interval includes zero, the data do not rule out no difference at the confidence level represented by that interval.

For use of acetaminophen as needed, the posted risk difference is -0.646, with a confidence interval from -0.928 to -0.364 and an unadjusted p-value of <0.001. For scheduled acetaminophen use, the risk difference is 0.646, with a confidence interval from 0.364 to 0.928 and an unadjusted p-value of <0.001. For chronic use of pain medication, the risk difference is -0.113, with a confidence interval from -0.410 to 0.185 and an unadjusted p-value of 0.468. These are unadjusted secondary results, not reported primary analyses.

A p-value measures how incompatible the observed data are with a specified null model, under the assumptions of the test. It is not the probability that the null hypothesis is true, and it does not measure clinical importance. The registry does not identify the test used for these comparisons in the record. The posted p-values should therefore be read as unadjusted summaries rather than as a complete analysis specification.

What does over-dispersion mean in general?

General statistical explanation: for count data, over-dispersion means that observed variability exceeds what a particular model assumes. If a model assumes variance tied closely to its mean but the data vary more widely, standard errors may be too small and uncertainty may be understated. This matters when selecting a count-data model. The primary endpoint is summarized by medians and inter-quartile ranges, but the registry does not report a model-based primary analysis or assess over-dispersion.

What do the sample-size illustrations mean?

The planning illustrations are recalculations based on the observed secondary effects, not the trial’s own design justification. The record states that the calculations use a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect set to a stated fraction of the observed effect. For the two medication-use comparisons with unadjusted p-values below 0.001, the illustration gives 9 participants per arm for 80% power and 11 for 90% power at 100% of the observed effect; at 75%, the corresponding figures are 16 and 20; at 50%, they are 34 and 45. For chronic use of pain medication, the corresponding values are 204 and 273 at 100%, 381 and 509 at 75%, and 895 and 1,198 at 50%.

These figures are planning illustrations, not observed power and not evidence that the original study was adequately or inadequately designed. Calculations based on an observed effect can be unstable, particularly when the available groups are small. Smaller assumed effects require larger planning counts in these illustrations. The record does not report its own sample-size assumptions or justification, so the recalculations cannot be treated as the trial’s prespecified design.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists several secondary outcome topics in addition to the primary medication-dose endpoint. The record does not report a multiplicity adjustment, a hierarchy for testing outcomes, or a statistical analysis plan specifying which comparisons were intended to be confirmatory. The posted p-values for the secondary medication-use comparisons are unadjusted. When multiple outcomes are tested, the chance of at least one apparently unusual result can increase; unadjusted p-values do not account for that broader testing context. The secondary findings should therefore be interpreted cautiously and not treated as a set of independent confirmatory tests.

Missing outcome data are a central limitation. The primary outcome description says that data were unavailable for patients lost to follow-up who did not complete the postoperative questionnaire, and reports 19 such patients in the standard-of-care arm and 18 in the study arm. The primary summaries use 15.0 participants in the standard-of-care arm and 13.0 in the study arm. The registry does not report whether missingness was related to pain, medication use, treatment assignment, or other participant characteristics. It also does not report imputation, sensitivity analyses, or another method for addressing missing outcomes.

The record does not state whether analyses followed randomized assignment, included only participants who completed the questionnaire, or used another analysis population. It does not report adherence to assigned medication schedules or how treatment changes were handled. These omissions make it difficult to assess how well the posted summaries preserve the intended randomized comparison.

The registry also does not report interim analyses or a sample-size justification. Those items should not be inferred from the posted results or planning illustrations. In particular, a sample-size calculation based on observed secondary effects is not a substitute for the trial’s original design rationale. Together, missing-outcome handling, unspecified analysis populations, and unreported multiplicity procedures restrict the strength of statistical conclusions that can be drawn from the posted record.

11. Safety Results

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

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports zero serious adverse events in each arm among the participants included in its adverse-event figures: 15 at risk in the standard-of-care arm and 13 at risk in the study arm. It also reports zero other adverse events in both arms and zero deaths. These figures describe the recorded events in the listed at-risk groups.

Zero recorded events do not establish that the risk of an adverse event is absent. With limited numbers of participants represented in the adverse-event figures, uncommon events may not appear, and the registry record does not provide confidence intervals or a detailed adverse-event narrative. The figures also do not describe events among participants whose follow-up or outcome data were unavailable unless those events were separately captured; the record does not explain the completeness of safety follow-up.

The absence of reported serious events should therefore be read as a statement about the recorded trial data, not as proof of comparative safety or a guarantee about future use. The registry does not report a statistical comparison of adverse events between arms. These data are descriptive and should be considered alongside the limited follow-up information and the distinction between the adverse-event population and the population contributing to the primary endpoint.

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

The posted primary outcome summaries describe opiate dose counts during the first postoperative week among participants with available questionnaire data. The median was 1.0 dose in the standard-of-care arm and 1.5 doses in the study arm, with inter-quartile ranges of 0.0 to 4.5 and 0.0 to 6.0, respectively. The summaries show overlapping distributions and do not include a formal estimate of the between-arm difference or its precision.

That evidence does not establish that the scheduled-acetaminophen regimen reduced opiate use. Nor does the primary summary prove that the regimens are equivalent or that a true difference is absent. Those conclusions would require a clearly reported comparison and adequate information about uncertainty, missing outcomes, and the analysis population. The registry record does not report those elements for the primary endpoint.

The secondary medication-use results show that participants’ reported use differed in ways that align with the assigned instructions. Such findings are useful for understanding regimen implementation, but medication-taking behavior is not the same outcome as pain intensity, recovery, or an overall assessment of the regimens. The registry lists additional pain-related outcomes, but the record does not report analyses for those topics. The available secondary comparisons are also unadjusted for multiple testing.

The results apply most directly to the participants whose outcomes were recorded in this trial and to the particular regimens described in the registry. The available information does not establish whether the findings generalize to other surgical settings, medication schedules, or patient groups. It also does not support a broad conclusion about safety from the zero adverse-event counts alone.

Overall, the registry provides descriptive evidence about medication use but leaves important inferential questions unresolved. Readers can identify the observed arm summaries and secondary patterns, while recognizing that the missing primary comparison, follow-up losses, and limited analysis reporting prevent a precise statement about the comparative effect on opiate use.

13. Why This Trial Matters Statistically

This trial raises a useful statistical distinction between an outcome’s clinical framing and the evidence actually reported for it. The primary question concerns opiate use, measured as a count of doses, but the registry presents arm-specific medians and inter-quartile ranges without a formal comparison. Those summaries are informative descriptions; they do not quantify uncertainty in the treatment contrast. A reader must resist treating a difference between two medians as a complete inferential result.

The endpoint also illustrates why the distribution matters. Dose counts can be concentrated at low values while a smaller number of participants have higher counts. Medians and inter-quartile ranges make central location and spread visible without assuming a symmetric distribution, but a suitable between-arm method still needs to be selected and reported. The record does not state which method was used or planned, so the statistical rationale cannot be evaluated.

Missing follow-up is particularly consequential because the primary endpoint comes from a postoperative questionnaire. The reported arm summaries represent participants with available outcome data, while the record notes substantial loss to follow-up in both arms. Without information about why outcomes are missing or sensitivity analyses, the reader cannot determine how much the available-case summaries may differ from the experience of all enrolled participants.

The secondary outcomes offer a further lesson: regimen adherence and clinical outcomes are related but distinct questions. Differences in reported use of scheduled or as-needed acetaminophen are understandable in light of the assigned instructions, yet they do not by themselves establish a difference in pain or opiate use. Unadjusted testing across multiple outcomes also calls for restraint.

For biostatisticians and clinical researchers, the record highlights the value of prespecifying the primary estimand, analysis method, missing-data strategy, multiplicity approach, and analysis population, then reporting those elements alongside estimates and confidence intervals. Such details would make the observed findings easier to interpret without relying on arm summaries alone.

14. 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 limitations are specific to the information recorded for this trial. First, the primary endpoint is based on questionnaire data, and the registry explicitly notes loss to follow-up in both arms. The posted outcome summaries therefore do not represent every enrolled participant. The record does not describe reasons for loss, compare participants with and without observed data, or report sensitivity analyses addressing missing outcomes.

Second, the primary outcome is summarized by a median and inter-quartile range, but the registry does not report a primary between-arm estimate, confidence interval, or p-value. The reader can compare the descriptive summaries but cannot assess the precision of their difference using the registry record. The stated inter-quartile ranges characterize observed variation rather than uncertainty in the treatment effect.

Third, the regimens differ in more than acetaminophen scheduling. The standard-of-care arm specifies acetaminophen/hydrocodone as needed, whereas the study arm specifies oxycodone as needed. Any difference between assigned arms would therefore concern the full regimens as described, not a clean isolated effect of scheduled acetaminophen.

Fourth, the registry records no masking and does not report details about adherence, allocation concealment, or treatment changes. It does not identify the analysis population or explain how deviations from assigned treatment were handled. These gaps make it harder to assess implementation and the preservation of the randomized comparison.

Finally, the registry lists additional pain-related secondary outcomes but does not report their analyses in the record. The available secondary p-values are unadjusted, and no multiplicity strategy or sample-size justification is reported. The adverse-event counts are descriptive and do not include an inferential comparison. These limitations constrain both the interpretation of the primary endpoint and the broader account of pain and safety outcomes.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Postoperative Pain Control in Septum and Sinus Surgery — NCT04149964.
• Registry record last updated 2023-08-31; status last verified 2023-08.
• Results first posted 2023-08-31.
• 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.

18. Record Summary

The registry record describes a completed phase 4 randomized, parallel-group study with no masking, sponsored by Corewell Health East. It lists 65 enrolled patients and compares a standard-of-care regimen using as-needed acetaminophen and acetaminophen/hydrocodone with a study regimen using scheduled acetaminophen and as-needed oxycodone.

The primary endpoint is the number of opiate doses taken for breakthrough pain during the first postoperative week. The reported medians are 1.0 in the standard-of-care arm and 1.5 in the study arm; the record does not report a formal primary comparison. It notes loss to follow-up and unavailable questionnaire data. Secondary medication-use comparisons are posted, but they are unadjusted, and other listed outcome topics lack reported analyses in the registry record.

The results are descriptive and do not establish the precision of the primary between-arm contrast. Missing outcomes, the absence of a reported primary analysis, and limited detail about analysis methods constrain interpretation.