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 Acupuncture and Nausea/Vomiting in Pediatric Patients (NCT01417741), a randomized na study. The primary outcome is Postoperative Nausea and Vomiting.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01417741 |
| Phase | NA |
| Condition | Postoperative Vomiting and Nausea |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 164 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Oregon Health and Science University |
| Results posted | Yes |
2. Clinical Question
Population
Pediatric patients undergoing tonsillectomy with or without adenoidectomy. The registry record does not give further eligibility details or describe the primary-outcome analysis population.
Intervention
Bilateral P6 acupuncture after anesthesia induction, removed when surgery ended, alongside standard antiemetic therapy.
Comparator
Standard antiemetic therapy without acupuncture.
Primary question
Does adding intraoperative P6 acupuncture to standard antiemetic therapy change the occurrence of postoperative nausea and vomiting, compared with standard therapy alone? The registry describes assessment during postoperative recovery and on the following day, but does not report the comparative primary-outcome results.
The clinical question is a comparison of two treatment strategies, not acupuncture in isolation: both groups were assigned standard antiemetic therapy, and the intervention group also received acupuncture. The outcome description refers to postoperative nausea and vomiting during recovery and on postoperative day one, with the latter assessed by a telephone survey of parents. The brief description also says nausea, retching, and vomiting events were monitored.
The posted record labels the primary outcome as a count of participants and describes the outcome as a percentage of participants who experienced it. These descriptions indicate a participant-level event outcome, but the record does not specify one combined definition or provide results separated by symptom, recovery period, or follow-up time. It therefore does not establish from the posted information whether any single symptom or time point was intended to determine the primary comparison.
3. Trial Design
The study is registered as NCT01417741, titled “Acupuncture and Nausea/Vomiting in Pediatric Patients.” Oregon Health and Science University is listed as the sponsor. The record lists a randomized allocation, a parallel-group model, and quadruple masking. The study status is completed. Its start is recorded as 2011-08 and its primary completion as 2014-08.
The two groups were standard therapy only and acupuncture plus standard therapy. The acupuncture intervention was bilateral P6 acupuncture applied after anesthesia induction and removed at the termination of surgery. Standard antiemetic therapy was given in both groups. The brief description says children were to be randomly assigned to treatment or control; it states a planned enrollment of 200. The record lists enrollment of 164. The reason for the difference between those figures is not reported in the registry record.
Random allocation is intended to make treatment groups comparable, on average, with respect to measured and unmeasured characteristics. It does not guarantee that groups will be identical, especially in a trial of this size. A parallel design means participants are assigned to one group rather than receiving both strategies in sequence. The record does not describe the randomization sequence, allocation concealment, or which people were masked. “Quadruple” is the masking classification recorded, but the roles included in that classification are not reported in the registry record.
The primary outcome timeframe is listed as 24 hours. The description refers to postoperative recovery and a telephone survey about postoperative day one. The record does not provide a fuller schedule of assessments, nor does it say how completion of follow-up was determined. No study results for the primary outcome or comparative analyses are listed. The record reports no analysis entries, so the allocation and outcome descriptions cannot be connected to an inferential result in the posted information.
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 | Standard Therapy Only | Acupuncture Plus Standard Therapy |
|---|---|---|
| STARTED | 75 | 86 |
| COMPLETED | 75 | 86 |
| NOT COMPLETED | 0 | 0 |
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 | Standard Therapy Only | Acupuncture Plus Standard Therapy | Total |
|---|---|---|---|---|
| Participants analysed | 75 | 86 | 161 | |
| Age, Continuous: Mean Age | years | 5.5 (SD 1.8) | 5.2 (SD 1.9) | 5.3 (SD 1.9) |
| Sex: Female, Male: Female | Participants | 33 | 45 | 78 |
| Sex: Female, Male: Male | Participants | 42 | 41 | 83 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | participants | 75 | 86 | 161 |
6. Primary Endpoint
The registry lists the primary outcome as Postoperative Nausea and Vomiting, measured over 24 hours.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary outcome is titled “Postoperative Nausea and Vomiting.” It is defined in terms of participants who experienced the outcome, with the registry describing measurement as a percentage of participants. The stated timeframe is 24 hours. The outcome description includes events during postoperative recovery and nausea and vomiting on postoperative day one, reported through a telephone survey. The brief description also mentions retching as an event monitored.
A participant-level event outcome is useful for describing how often an event occurs in each treatment group. In a randomized comparison, the groups’ event counts or proportions can be used to estimate the difference between treatment strategies, provided the outcome definition and analysis population are clear. A binary outcome generally records whether each participant did or did not experience the defined event during the relevant period; an event count at group level can then summarize those participant-level classifications.
Here, the registry record does not clarify whether nausea, retching, and vomiting were combined into one primary definition, whether symptoms were assessed separately, or how the recovery and next-day assessments were combined. It also does not report the primary-outcome counts, proportions, effect estimate, confidence interval, or test result. The endpoint’s intended clinical subject is clear, but its detailed operational definition and comparative result are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted record identifies a randomized comparison of standard antiemetic therapy alone with the same standard therapy plus intraoperative P6 acupuncture. It also gives a primary outcome title, a 24-hour timeframe, and a description of assessment during recovery and on postoperative day one. These details establish what the trial was designed to examine. They do not establish what the comparison found.
No primary-outcome group counts or proportions are reported in the registry record. There is consequently no posted effect estimate to interpret, and no reported confidence interval or p-value for the primary comparison. The record lists zero analyses. Without those results, the direction and magnitude of any group difference, and the precision of any estimate, cannot be assessed from the registry information.
The outcome description spans symptoms and assessment occasions. The record’s note that the primary outcome has several categories or time points and was not reduced to one comparison is important: a single summary result cannot be reconstructed from the information available. A difference at one assessment would not automatically represent a difference across all symptoms or times. Nor does the record say how multiple assessments were combined or which one would govern the primary conclusion.
General statistical interpretation requires more than a point estimate. A confidence interval describes the range of effect values reasonably compatible with the data under the model and assumptions used; its width conveys precision. A p-value, when reported, addresses compatibility of the observed data with a specified null model, not the probability that a treatment strategy is effective. Neither can be interpreted for the primary outcome without the actual analysis results and methods.
The enrollment entry is 164, while the brief description states that 200 children would be assigned. This difference is visible in the record, but the reason is not reported in the registry record. It cannot by itself establish whether recruitment stopped early, whether the target changed, or whether the planned sample-size rationale was met. The record does not report a sample-size justification or an explanation of enrollment.
The adverse-event entries list zero serious adverse events in each group and zero deaths in each group. These safety counts do not substitute for the missing primary-outcome comparison. In particular, they do not indicate whether nausea, retching, or vomiting differed between groups. Overall, the registry record supports a description of the trial question, design, and limited safety counts, but not a conclusion about the primary endpoint’s comparative result.
9. Statistical Methods Explained
Several statistical ideas help explain what can and cannot be learned from the registry record. The key distinction is between a design description and an analysis result. Randomization and masking describe how a trial was organized; an effect estimate and its uncertainty describe what the observed outcome data show. The posted record contains the former but does not report the primary comparison’s results.
What does random allocation contribute?
In a randomized trial, assignment is determined by a chance-based process rather than by a participant’s prognosis or a clinician’s choice. If implemented as intended, this helps prevent systematic differences between groups at the point of assignment. It supports a causal comparison of assigned strategies, subject to appropriate follow-up and analysis. Randomization does not ensure that every characteristic is balanced, and it does not prevent missing outcomes, deviations from assigned treatment, or measurement problems.
The registry lists randomized allocation but does not describe the sequence-generation method or allocation concealment. Those details matter because a predictable or inadequately concealed assignment process can weaken the protection randomization is intended to provide. The record also does not specify the analysis population, such as whether participants would be analyzed according to their assigned groups regardless of treatment received.
What does masking mean?
The record classifies the study as quadruple-masked. Masking is intended to limit the ways knowledge of assignment can influence care, symptom reporting, outcome assessment, or analysis. Its practical effect depends on who was masked and whether masking was maintained. The record does not identify the masked roles or provide an assessment of masking success. Because acupuncture is a procedure, the details of how treatment assignment was concealed from participants and staff are especially relevant, but they are not reported in the registry record.
How should a participant-level event outcome be analyzed?
For a binary outcome, each participant is classified according to whether the defined event occurred during the stated period. Group-level results may be presented as counts and proportions, followed by an effect measure comparing the groups. Common effect measures include a difference in proportions or a ratio of proportions. These answer different questions: an absolute difference expresses the contrast in event frequency, while a ratio expresses one frequency relative to another. No effect measure or primary-outcome group result is reported in the registry record, so neither can be interpreted for this trial.
A confidence interval accompanies an estimate to communicate uncertainty. A narrow interval indicates greater precision under the analysis assumptions; a wide interval indicates less precision. The interval can also show which effect values remain compatible with the observed data. It is not a guarantee that the true effect lies within the particular interval. Since the primary result and its interval are not reported, the precision of the trial’s primary comparison cannot be assessed.
Why does the outcome’s structure matter?
The registry describes symptoms during recovery and on postoperative day one, and mentions nausea, retching, and vomiting. When an endpoint includes several symptoms or assessment occasions, the analysis needs a clear rule for combining or separating them. A combined outcome can answer whether any component occurred, but may conceal differences among components. Separate analyses retain symptom-specific information but create multiple comparisons and may produce results that vary by assessment time. The registry record explicitly does not reduce the several categories or time points to one comparison. It does not report a hierarchy or a rule for interpreting such results.
What is multiplicity?
Multiplicity arises when several outcomes, time points, or comparisons are tested. Even when each individual test is conducted at a chosen significance level, conducting many tests can increase the chance of at least one apparently notable result under a null setting. Statistical approaches can address this, for example by defining one primary comparison in advance, adjusting inference, or treating additional analyses as exploratory. Which approach was planned for this trial is not reported in the registry record. The stated planning illustration uses a two-sided significance level of 0.05, equal allocation, and a normal approximation, but it is not the trial’s own analysis plan.
What does the sample-size information mean?
The record describes a planning illustration based on the observed effect, with the effect to detect expressed as a fraction of that observed effect. It says that the illustration assumes equal allocation and a normal approximation, and distinguishes participant-per-arm calculations from total-event calculations for time-to-event settings. These are generic planning assumptions, not evidence that the study had a particular probability of detecting an effect. Sample-size planning illustrations are not observed power and should not be treated as trial findings. No numerical illustration results or trial-specific sample-size justification are reported in the registry record.
Finally, safety counts and efficacy outcomes answer different questions. A count of serious adverse events can describe reported serious harms in the listed groups. It does not estimate the primary symptom outcome, and it does not resolve uncertainty about that outcome. Each result must be interpreted according to its definition, denominator, follow-up, and analysis method; several of those details are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome description covers more than one symptom and more than one assessment occasion: postoperative recovery and postoperative day one. The registry record notes that the outcome has several categories or time points and was not reduced to one comparison. That leaves uncertainty about whether the intended primary analysis treated symptoms as a combined event, analyzed each symptom separately, or used another prespecified rule. The record does not report a hierarchy of outcomes or a multiplicity adjustment.
Multiplicity is a general concern when several statistical comparisons are made. Looking across multiple symptoms or times can increase the chance that at least one result appears notable by chance. A prespecified primary comparison, an adjustment method, or clear labeling of secondary analyses can help readers distinguish confirmatory from exploratory findings. The method used for this study is not reported in the registry record.
Missing-data handling is also not reported. The record does not state how incomplete recovery assessments or unanswered follow-up calls were handled, whether participants with missing outcomes were excluded or otherwise included, or how the analysis population was defined. These details matter because observed results can be affected if outcome availability differs between groups or is related to participants’ symptoms.
The record lists zero analysis entries and does not provide primary-outcome estimates or group results. It therefore does not show whether an intention-to-treat analysis, a per-protocol analysis, or another approach was used. No interim analyses, stopping rules, or statistical analysis plan are described 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 |
|---|---|---|---|
| Standard Therapy Only ( AE Group) | 0 | 75 | 0.0% |
| Acupuncture Plus Standard Therapy | 0 | 86 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Standard Therapy Only ( AE Group) | 0 of 75 |
| Acupuncture Plus Standard Therapy | 0 of 86 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 1% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Standard Therapy Only ( AE Group) | 0 of 75 |
| Acupuncture Plus Standard Therapy | 0 of 86 |
The adverse-event entries list the number at risk and the number affected for serious and other adverse events in each group. For standard therapy only, the record lists 75 at risk, zero serious adverse events, zero other adverse events, and zero deaths. For acupuncture plus standard therapy, it lists 86 at risk, zero serious adverse events, zero other adverse events, and zero deaths. No serious adverse-event terms are listed.
These are the safety figures recorded for the groups, not the primary-outcome results. In particular, the counts do not report postoperative nausea, retching, or vomiting by group. Zero recorded events means none are listed in these adverse-event fields; it does not establish that no event could occur or that the groups have identical safety profiles.
Interpretation of adverse-event counts depends on how events were defined, collected, and followed, as well as on the participants included in the safety summary. Those details are not reported in the registry record. The at-risk counts in the safety entries should not be assumed to be the denominators used for the primary-outcome analysis, because that analysis and its population are not reported.
12. What the Result Does, and Does Not, Mean
The registry record identifies a completed, randomized, parallel-group comparison of standard antiemetic therapy alone against standard therapy plus P6 acupuncture in pediatric patients undergoing tonsillectomy with or without adenoidectomy. It describes the primary outcome as postoperative nausea and vomiting over a 24-hour timeframe, with assessments during recovery and on postoperative day one. These registry entries clarify the clinical question and the intended comparison.
The record does not report the comparative primary-outcome data. It gives no group counts or proportions, effect estimate, confidence interval, or p-value. As a result, the posted information cannot show whether the groups differed, in what direction, by how much, or with what precision. The absence of a reported estimate is not evidence that the strategies had the same outcome.
The outcome description includes several symptoms and assessment occasions, and the record says they were not reduced to one comparison. Consequently, even a hypothetical difference at one time or for one symptom should not be generalized to all symptoms and time points without an explicit analysis plan and results. The registry also does not report how incomplete follow-up, such as an unanswered parent telephone survey, was handled.
The safety entries report zero serious adverse events and zero deaths in both groups, along with zero other adverse events. Those entries describe the posted safety counts but do not answer the efficacy question. They also do not establish that rare or unrecorded events were absent. The record does not supply details about adverse-event ascertainment or the analysis population.
The enrollment entry is 164, while the brief description gives a planned enrollment of 200. The registry does not explain this difference, so it should not be interpreted as proof of a particular recruitment or design decision. In sum, the record describes the trial and some safety counts, but it does not contain the primary results needed to judge the observed comparative effect.
13. Why This Trial Matters Statistically
This trial is statistically instructive because the intervention is an addition to a shared treatment strategy. Both groups were assigned standard antiemetic therapy, while only one group also received intraoperative P6 acupuncture. The meaningful contrast is therefore the effect of adding acupuncture under the recorded trial conditions, not a comparison of acupuncture with no antiemetic therapy.
It also highlights why an outcome needs a precise definition. Nausea, retching, and vomiting can be considered separately or combined, and assessments during recovery need not answer exactly the same question as a parent report on postoperative day one. If a registry lists multiple symptoms and occasions without a single comparison rule, readers cannot safely treat all of them as one endpoint or select whichever result appears most favorable.
Randomized allocation and masking are important design features, but they do not replace transparent results. To evaluate a randomized comparison, readers need the group outcome data, the analysis population, an effect estimate, and an indication of uncertainty. The registry record identifies randomization and quadruple masking but does not report the primary analysis or its results. This leaves the central statistical question unresolved in the posted record.
The difference between the enrollment entry and the planned enrollment stated in the brief description also illustrates the importance of distinguishing trial conduct from design planning. Without an explanation, the record does not show why the figures differ or how that affected the study’s precision. Likewise, planning illustrations based on an observed effect do not establish the trial’s probability of detecting a clinically meaningful effect.
Finally, the safety entries should be read within their scope. Zero listed serious adverse events and deaths are useful descriptive details, but they are not evidence about the primary symptom outcome. Clear separation of outcome types, denominators, and analysis results is essential to avoid drawing conclusions beyond what the registry record contains.
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 most important limitation of the posted record for statistical interpretation is that it does not include the primary-outcome results. There are no group-level event counts or percentages, no estimate of the contrast, and no confidence interval or p-value. The record also lists no analysis entries. The trial’s primary comparative finding therefore cannot be assessed from these registry entries.
The primary endpoint description combines a 24-hour timeframe with references to recovery and postoperative day one, and the brief description includes nausea, retching, and vomiting. The registry notes that the outcome has several categories or time points and was not reduced to one comparison. It does not clarify the exact event definition, whether symptoms were combined, or how assessments were intended to contribute to the primary analysis.
Important design and analysis details are not reported in the registry record. These include eligibility criteria beyond the pediatric surgical population, the randomization method, allocation concealment, the identities of the masked roles, the analysis population, missing-data procedures, and the statistical analysis plan. The record does not explain how the stated planned enrollment of 200 relates to the enrollment entry of 164.
The safety summary is limited to the recorded event counts and at-risk entries. The record does not describe the method or timing of adverse-event collection, nor does it establish whether the safety and primary-outcome populations were the same. The absence of listed events should therefore be interpreted as a feature of the posted safety fields, not as a comprehensive account of all possible harms or of the efficacy outcome.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Acupuncture and Nausea/Vomiting in Pediatric Patients — NCT01417741.
- Registry record last updated 2019-08-28; status last verified 2019-08.
- Results first posted 2019-08-28.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
NCT01417741 is a completed, randomized, parallel-group trial sponsored by Oregon Health and Science University. The record lists quadruple masking, enrollment of 164, a start date of 2011-08, and primary completion in 2014-08. The brief description states a planned enrollment of 200 children.
The comparison was standard antiemetic therapy alone versus standard therapy plus bilateral P6 acupuncture after anesthesia induction. The primary outcome is postoperative nausea and vomiting, with a 24-hour timeframe and assessments described during recovery and on postoperative day one. The record identifies multiple symptoms or assessment occasions but does not reduce them to one comparison.
No primary-outcome results, comparative estimates, confidence intervals, or p-values are reported, and the record lists zero analyses. The safety entries list zero serious adverse events, zero other adverse events, and zero deaths in each group. The reason for the difference between planned enrollment and recorded enrollment, and several analysis and follow-up details, are not reported in the registry record.