This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Non-opioids for Analgesia After Adenotonsillectomy in Children (NCT03618823), a randomized phase 1, phase 2 study. The primary outcome is Average Pain Burden.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03618823 |
| Phase | Phase 1, Phase 2 |
| Condition | Adenotonsillectomy, Post-operative Analgesia, Opioid Use |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 268 |
| Arms in the primary outcome | n/a |
| Lead sponsor | David Chi, MD |
| Results posted | Yes |
2. Clinical Question
Population
Children aged 3–17 undergoing adenotonsillectomy. The registry lists enrollment of 268, but the primary outcome analysis population was limited to participants who completed the take-home pain diary and had pain scores recorded.
Intervention
Non-opioid pain control with acetaminophen and ibuprofen. The registry describes a pain diary for measuring pain, though its description of when diary completion ends is not fully consistent across the arm description and primary outcome record.
Comparator
Opioid pain control with oxycodone, acetaminophen, and ibuprofen. The trial is described as randomized, parallel-group, and unmasked.
Primary question
How does average pain burden, measured with the Wong-Baker FACES pain metric over the postoperative period, compare between the two regimens? The registry record defines the outcome but does not report arm-level primary outcome estimates or a comparison.
The trial’s stated aim was to assess pain control and complications when children received non-opioid medication only versus a combination that included an opioid. The primary endpoint was average pain burden over 14 days post-operatively. Participants recorded maximum pain before and after taking medication in a take-home diary, and the recorded pain ratings were used to form a mean score. The scale runs from 0 (min) to 10 (max), with higher scores indicating worse pain.
This comparison is clinically framed around whether pain control differs between the regimens, alongside questions about emergency department or urgent care visits and medication side effects. Those secondary outcomes are listed in the registry, but their results are not reported in the registry record. The available information therefore establishes the research question and outcome definitions, not whether one regimen had lower pain or fewer complications.
3. Trial Design
This was a randomized, parallel-group trial listed as PHASE1 and PHASE2. It compared opioid pain control, using oxycodone with acetaminophen and ibuprofen, with non-opioid pain control, using acetaminophen and ibuprofen. The registry states that masking was none. Participants and study personnel therefore were not described as masked to the assigned regimen.
The record lists enrollment of 268. The study began on 2018-10-25, had a primary completion date of 2020-05-18, and has a status of TERMINATED. The reason for termination is not reported in the registry record. The record does not describe the allocation ratio, the method used to generate or conceal the random sequence, or how assignment was implemented.
The primary endpoint was average pain burden measured with the Wong-Baker FACES pain metric. Participants were asked to record maximum pain before and after medication in a take-home diary. The primary outcome population is described as participants who completed the diary and had pain scores recorded. This means the analysis population, as defined in the record, need not include everyone enrolled; the number meeting that criterion is not reported in the registry record.
The arm descriptions do not give a consistent account of the diary schedule. The opioid arm text says the diary would be completed by post-operative day 1, while the primary endpoint is defined over 14 days post-operatively. The non-opioid arm text says the diary would be completed by post-operative day 14, and its description ends with an incomplete phrase. The record does not explain this difference.
The registry also lists emergency department or urgent care visits and medication side effects as secondary outcomes. It lists 14 outcome measures and 2 analyses. A protocol-level statistical analysis plan, including the planned model and handling of repeated diary entries, is 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
| Stage | Opioid Pain Control | Non-opioid Pain Control |
|---|---|---|
| STARTED | 132 | 136 |
| COMPLETED | 69 | 75 |
| NOT COMPLETED | 63 | 61 |
Reasons for not completing this period:
| Reason | Opioid Pain Control | Non-opioid Pain Control |
|---|---|---|
| Lost to Follow-up | 63 | 61 |
Analysis population for the primary outcome, as defined in the registry: Participants were analyzed for average pain burden if they completed the take-home pain diary and pain scores were recorded.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Opioid Pain Control | Non-opioid Pain Control | Total |
|---|---|---|---|---|
| Participants analysed | 132 | 136 | 268 | |
| Age, Continuous | Years | 8.39 (SD 3.33) | 8.15 (SD 3.33) | 8.27 (SD 3.32) |
| Sex: Female, Male: Female | Participants | 69 | 68 | 137 |
| Sex: Female, Male: Male | Participants | 63 | 68 | 131 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 5 | 6 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 127 | 120 | 247 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 4 | 11 | 15 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 1 | 1 | 2 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 9 | 11 | 20 |
| Race (NIH/OMB): White | Participants | 118 | 120 | 238 |
| Race (NIH/OMB): More than one race | Participants | 2 | 1 | 3 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 2 | 3 | 5 |
| BMI Centile | Percentage | 66.42 (SD 32.81) | 67.20 (SD 31.44) | 66.81 (SD 32.06) |
6. Primary Endpoint
The registry lists the primary outcome as Average Pain Burden, measured over 14 days post-operatively.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Error |
| Unit | Score on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is average pain burden over 14 days post-operatively, recorded with the validated Wong-Baker FACES pain metric. Participants were given a take-home diary and asked to report maximum pain before and after taking pain medication. The registry says the mean of these pain ratings is the primary outcome measure. Scores range from 0 (min) to 10 (max); higher scores indicate worse pain.
A mean summarizes the central level of a continuous measure across the recorded observations. Using a pain diary can capture participants’ reports during recovery rather than relying only on a single assessment. The before-medication and after-medication entries also describe pain in relation to medication use, although the registry record does not explain how those entries were combined or modeled.
For a comparison between regimens, an arm-level mean and a contrast between means would help describe the direction and size of any difference. The registry record defines the endpoint but does not report these estimates, their uncertainty, or a primary comparison result. It also specifies that only participants who completed the diary and had pain scores recorded were analyzed for average pain burden. The number of participants included under that rule is not reported in the registry record.
The diary timing descriptions warrant care: the opioid arm description refers to completion by post-operative day 1, whereas the primary outcome covers 14 days post-operatively. The record does not reconcile those descriptions, so the precise diary schedule cannot be established from the registry text alone.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted registry information is sufficient to identify the trial question, treatment regimens, primary outcome definition, and some safety counts. It is not sufficient to interpret the comparative primary outcome. No arm-level average pain scores, treatment contrast, confidence interval, or primary-outcome significance test is reported in the registry record. Consequently, the posted information does not show how pain burden differed between the groups or how precisely that difference was estimated.
The primary endpoint is a mean of pain ratings on the Wong-Baker FACES scale, where higher values indicate worse pain. In general, a mean difference communicates how far apart the group averages are, while a confidence interval communicates the range of values reasonably compatible with the data and analysis. Neither is available. The scale limits and direction help explain what a future estimate would mean, but they cannot substitute for the missing estimate.
The participant counts in the adverse-event record should be read as safety summaries, not as evidence about the primary pain endpoint. The opioid pain-control group lists 9 participants with serious adverse events among 149 at risk; the non-opioid pain-control group lists 4 among 119 at risk. The record also lists other adverse events affecting 38 among 149 and 22 among 119, respectively. These are reported counts. Without a stated analysis method, event definitions, and further context, they should not be treated as a formal comparative estimate of safety.
The trial is marked TERMINATED, but the reason is not reported in the registry record. Termination alone does not establish why the study ended or what its findings were. Likewise, enrollment of 268 does not establish how many participants contributed to the primary endpoint, because the analysis population required completed diaries and recorded scores.
Overall, the record describes a randomized comparison but leaves key pieces of evidence unavailable for interpretation: the primary outcome results, the methods used to analyze them, the number included in that analysis, and the reason for termination. The tables, plots, and planning illustrations elsewhere on the page should be read in light of those limits. In particular, sample-size planning illustrations are not observed power and cannot supply the missing treatment-effect result.
9. Statistical Methods Explained
The registry describes a randomized, parallel-group comparison of two pain-control regimens. Random assignment is intended, in general, to reduce systematic differences between treatment groups at the point of allocation. It does not guarantee that groups will be identical, and the benefit of randomization depends on the allocation process being implemented as planned. The registry record does not report the sequence-generation or allocation-concealment methods, so those details cannot be assessed.
What does the mean represent?
The primary outcome is a mean of pain scores, a continuous measure. In general, a mean gives a summary of the observed score level, while individual observations may vary around it. The Wong-Baker FACES scale in this record ranges from 0 (min) to 10 (max), and higher scores indicate worse pain. The average can describe overall pain burden, but it can also conceal variation between participants or changes during recovery. The registry record does not say whether the reported mean would be calculated separately for diary days, before-medication reports, after-medication reports, or some combined set of entries.
What would a standard error tell us?
The outcome description specifies a mean and standard error as the summary format. In general, a standard error describes the precision of an estimated mean: smaller standard errors indicate less sampling uncertainty around that estimate under the model used. It is not the same as the spread of individual pain scores. A confidence interval is often built from an estimate and its standard error and gives a range expressing uncertainty under the chosen method. The registry record does not provide arm-level means, standard errors, or confidence intervals, so the precision of the primary outcome cannot be evaluated from this record.
Why does the diary schedule matter?
Diary measurements collected from the same participant are related rather than independent. In general, analysis of repeated measurements should account for that within-participant relationship if multiple entries contribute to an estimate. How the entries are summarized or modeled can affect both the estimated mean and its uncertainty. The record describes pain entries before and after medication and an average over 14 postoperative days, but does not report a model or a precise rule for combining entries. In addition, the arm descriptions differ on the diary completion timeframe: the opioid description says by post-operative day 1, while the primary endpoint covers 14 days and the non-opioid description says through post-operative day 14. This leaves the intended measurement schedule unclear in the registry text.
What does randomization not resolve?
Randomization addresses confounding at assignment in general, but it does not by itself address missing outcome measurements, departures from assigned treatment, or differences in follow-up. The stated primary analysis population includes participants who completed the take-home diary and had pain scores recorded. If diary completion is related to pain, treatment, or other participant characteristics, an analysis restricted to complete records may not represent everyone randomized. This is a general concern about selection into an analysis population, not evidence that such a bias occurred in this trial. The number of participants meeting the diary criterion and the approach to incomplete diaries are not reported in the registry record.
How should the planning illustrations be read?
The page includes sample-size planning illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. The illustrations consider the stated fraction of the observed effect as the effect to detect. These are planning calculations, not the trial’s own design justification and not observed power. They do not show that the trial had a particular probability of detecting an effect after completion. The trial’s own sample-size justification is not reported in the registry record, and the specific illustration values should be read from the accompanying section rather than inferred from the enrollment count.
What does multiplicity mean?
The registry lists 14 outcome measures and 2 analyses. In general, testing several outcomes or comparisons can increase the chance of at least one apparently notable result when no adjustment or prespecified hierarchy is used. A statistical plan may address this through a primary-outcome hierarchy, adjusted thresholds, or other methods. The registry record does not report whether such a plan was used, how the two listed analyses relate to the outcomes, or whether any multiplicity adjustment was applied. Thus, multiplicity handling cannot be evaluated from the listed counts alone.
Finally, the primary endpoint is not reduced to a single comparison in the posted display because it contains several categories or time points. Without the underlying estimates and analysis description, the record supports an explanation of the intended statistical quantities but not a reconstruction of the sponsor’s analysis or a conclusion about the comparative effect.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 14 outcome measures and 2 analyses. It also identifies average pain burden as the primary outcome and lists emergency department or urgent care visits and medication side effects as secondary outcomes. The record does not report a testing hierarchy, a family of comparisons, an adjustment for multiple testing, or a statistical analysis plan explaining how the primary and secondary outcomes were to be interpreted together. In general, testing multiple outcomes can raise the chance of finding an apparently unusual result by chance; whether that concern was addressed is not reported in the registry record.
The record defines the primary outcome population as participants who completed the take-home pain diary and had pain scores recorded. It does not report how many participants met that definition, how many had incomplete diaries, or how missing entries were handled. It also does not describe whether the analysis included all randomized participants, how any departures from assigned medication were treated, or whether a sensitivity analysis was conducted. These details matter because the analyzed participants may differ from those with missing outcome data.
The endpoint description covers pain reports before and after medication across 14 days post-operatively, but the arm descriptions differ about diary completion timing. The record does not explain whether all scheduled observations were required or how partial diaries contributed to the mean. The missing-data assumptions and the analysis population beyond the diary-completion rule are not reported in the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Opioid Pain Control | 9 | 149 | 6.0% |
| Non-opioid Pain Control | 4 | 119 | 3.4% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Opioid Pain Control | 0 of 149 |
| Non-opioid Pain Control | 0 of 119 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Opioid Pain Control | 38 of 149 |
| Non-opioid Pain Control | 22 of 119 |
Most frequent serious adverse event terms
| Event term | Organ system | Opioid Pain Control | Non-opioid Pain Control |
|---|---|---|---|
| Post-Tonsillectomy Hemorrhage Requiring Operative Intervention | Surgical and medical procedures | 7 of 149 | 3 of 119 |
| Dehydration Requiring Inpatient Admission | General disorders | 2 of 149 | 0 of 119 |
| Oxygen Desaturation | Respiratory, thoracic and mediastinal disorders | 0 of 149 | 1 of 119 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Opioid Pain Control | Non-opioid Pain Control |
|---|---|---|---|
| Nursing Phone Call for Pain | General disorders | 23 of 149 | 15 of 119 |
| Post-Tonsillectomy Hemorrhage Not Requiring Operative Intervention | Vascular disorders | 13 of 149 | 8 of 119 |
| Nausea or Vomiting | General disorders | 10 of 149 | 3 of 119 |
| Emergency Department Visit for Pain | General disorders | 8 of 149 | 0 of 119 |
Serious events with the highest arm-level rate: post-tonsillectomy hemorrhage requiring operative intervention (4.7%), dehydration requiring inpatient admission (1.3%), oxygen desaturation (0.8%).
The registry lists serious adverse events by arm. In the opioid pain-control group, 9 participants were affected among 149 at risk; in the non-opioid pain-control group, 4 were affected among 119 at risk. It lists other adverse events affecting 38 among 149 and 22 among 119, respectively. The record reports 0 deaths in each group. These figures are counts from the posted safety record and should not be read as a formal comparison unless the event definitions and analysis methods are also considered.
The registry identifies the top serious-event terms as Post-Tonsillectomy Hemorrhage Requiring Operative Intervention (4.7%), Dehydration Requiring Inpatient Admission (1.3%), and Oxygen Desaturation (0.8%). These percentages are reproduced as listed; the denominator and calculation details for these terms are not reported in the registry record. The record also does not explain whether participants could contribute more than one event or how seriousness and attribution were determined.
The counts at risk differ between the listed groups. Counts alone do not establish that the regimens differ in safety, and they do not describe the uncertainty around a comparative effect. The registry status is TERMINATED; the reason for termination is not reported in the registry record.
12. What the Result Does, and Does Not, Mean
This trial asks a relevant comparative question: whether pain burden and complications differ when children receive acetaminophen and ibuprofen alone or those medicines with oxycodone after adenotonsillectomy. The registry identifies a randomized, parallel-group design and defines a diary-based primary outcome. It also records serious and other adverse-event counts. These details clarify what was studied and what kinds of outcomes were tracked.
They do not establish the comparative result. The primary outcome’s arm-level means, treatment contrast, uncertainty interval, and test result are not reported in the registry record. Without those values, the posted data cannot show the magnitude or direction of a pain difference, nor how precisely it was estimated. Safety counts likewise do not by themselves demonstrate a difference between regimens.
The distinction between a planned question and an observed result is important. A stated aim to evaluate whether pain control differs is not a finding that it does or does not differ. Similarly, the registry’s rationale about potentially reducing opioid prescriptions is background for the research question, not evidence that the trial established such a conclusion.
The analysis population also matters. The primary endpoint was evaluated among participants who completed the diary and had pain scores recorded, but the number meeting this condition is not reported. The registry’s diary timing descriptions are not fully aligned, and the reason for the study’s TERMINATED status is not reported. These uncertainties limit what can be said about completeness, implementation, and interpretation.
The tables, plots, and sample-size section should therefore be read as statistical displays and planning context, not as a substitute for absent primary outcome findings. Planning illustrations based on an observed effect are not observed power and do not establish what the trial concluded. The registry record supports description of the design and available safety counts, but not a conclusion that either regimen produced better pain control or fewer complications.
13. Why This Trial Matters Statistically
Statistically, this trial illustrates why a randomized design and a clearly defined endpoint are only part of the evidence needed to interpret a clinical comparison. Randomization describes how groups are intended to be formed, while the primary endpoint specifies what is measured. To understand the result, readers also need the group estimates, the treatment contrast, its uncertainty, and enough information about who contributed data and how those data were analyzed. The registry record gives the design and outcome definition but does not report the primary comparison.
The diary outcome raises practical analysis questions that are common in longitudinal clinical studies. Repeated reports from a participant are related, and an average over a recovery period depends on which reports are included and how incomplete records are handled. Here the registry describes before- and after-medication reports, but does not give a detailed aggregation or modeling approach. The diary timeframe descriptions also differ between the arm text and the primary endpoint description.
Safety data require similar care. Counts of affected participants are useful descriptive information, but interpretation of differences requires clarity about event definitions, denominators, follow-up, and uncertainty. The listed serious and other adverse-event counts do not supply a formal comparative analysis on their own.
Finally, the record lists 14 outcome measures and 2 analyses, while not reporting a multiplicity plan. That matters because readers need to know which results were primary and how multiple comparisons were handled. The trial’s status is TERMINATED, but the reason is not reported in the registry record. Taken together, these points show why transparent outcome reporting and analysis documentation are essential: without them, a well-defined question cannot be translated into a reliable interpretation of the effect.
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.
The main limitation of the available registry record is that it defines the primary pain outcome without reporting the arm-level results or comparative estimate. It does not provide the means, a treatment contrast, confidence intervals, or a primary-outcome test result. The number of participants who completed the diary and had pain scores recorded is also not reported, so the size of the primary analysis population cannot be determined from the record.
The diary schedule is unclear. The primary endpoint covers 14 days post-operatively, and the non-opioid arm description refers to diary completion by post-operative day 14. The opioid arm description instead says the diary would be completed by post-operative day 1. The non-opioid arm text also ends with an incomplete phrase. The record does not clarify whether these are differences in intended follow-up, wording errors, or another issue.
The record does not report the reason for the TERMINATED status, the randomization implementation details, adherence to assigned regimens, or the handling of missing diary entries. It does not provide the statistical analysis plan, including the model for repeated pain reports or the approach to multiplicity across the listed outcomes. These omissions prevent a full assessment of analysis choices and their implications.
The safety record provides counts and selected serious-event terms, but does not provide further detail on event definitions, attribution, follow-up, or the basis for the listed percentages. These limitations concern what can be interpreted from the registry record; they do not establish that a particular problem occurred in trial conduct or analysis.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Non-opioids for Analgesia After Adenotonsillectomy in Children — NCT03618823.
- Registry record last updated 2021-11-10; status last verified 2021-10.
- Results first posted 2021-11-10.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT03618823, titled Non-opioids for Analgesia After Adenotonsillectomy in Children, is listed as a randomized, parallel-group, unmasked PHASE1 and PHASE2 trial. It compared acetaminophen and ibuprofen with a regimen adding oxycodone. The registry lists enrollment of 268 and a primary endpoint of average pain burden measured using the Wong-Baker FACES pain metric over 14 days post-operatively.
The record lists secondary outcomes involving emergency department or urgent care visits and medication side effects, as well as serious and other adverse-event counts. It lists 14 outcome measures and 2 analyses. The study status is TERMINATED; its reason is not reported in the registry record.
Arm-level primary outcome estimates, the primary comparative result, the analysis plan, and the number included in the diary-based analysis are not reported in the registry record. The record’s diary timing descriptions are not fully consistent.