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 The Effects of Reducing Stomach Acid on Post-tonsillectomy Pain (NCT00472186), a randomized phase 4 study. The primary outcome is The Primary Outcome is the Number of Days to Become Free of Narcotic Pain Medication..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00472186 |
| Phase | Phase 4 |
| Condition | Post-tonsillectomy Pain, Post-tonsillectomy Activity, Post-tonsillectomy Hydration |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Boston Children's Hospital |
| Results posted | Yes |
2. Clinical Question
The trial asked whether adding lansoprazole after tonsillectomy could affect recovery, with the primary outcome defined as the number of days until a participant became free of narcotic pain medication. The registry describes the underlying hypothesis that stomach acid reaching the mouth after surgery might increase pain, and that an acid-suppressing medication might reduce pain and the need for narcotic medication. This is the proposed rationale, not a result demonstrated by the record.
Population
People undergoing tonsillectomy were the intended population. The registry does not report eligibility criteria, age range, or other participant characteristics. It reports enrollment of 2, but does not provide the number assigned to each arm or describe the enrolled participants.
Intervention
The intervention was postoperative administration of lansoprazole. The registry does not report the dose, schedule, duration, or other details of how the medication was to be administered.
Comparator
The comparison group was assigned placebo after surgery. The record identifies the placebo arm but does not describe its formulation or administration schedule.
Primary question
The primary outcome was the number of days to become free of narcotic pain medication, with a stated timeframe of 2 weeks. The record contains no reported participant outcome data, so it does not establish how the groups compared on this outcome.
The registry also names days to become free of pain, return to normal activity, and return to normal fluid intake as secondary outcomes. These outcomes concern aspects of postoperative recovery, but their definitions and results are not reported in the registry record. The intended clinical question can therefore be described, while the comparative effect cannot be estimated from the posted results.
3. Trial Design
The record describes a Phase 4, randomized, triple-masked, parallel-group trial sponsored by Boston Children's Hospital. Its two listed interventions were lansoprazole and placebo, administered postoperatively. In a parallel-group design, participants are assigned to one of the study groups and followed in that group. The registry does not report the allocation ratio or the randomization method, so those details cannot be characterized further.
The recorded enrollment is 2. The study began in 2008-06, had a primary completion date of 2011-02, and is listed as terminated. The registry states that termination was due to low recruitment. It also says that only one participant returned logbooks with data and that confidentiality concerns led to no data being reported. This limits what can be learned from the record about both the trial's conduct and its outcomes.
Triple masking indicates that the record classifies the study as masked, but does not identify which roles were masked or explain the procedures used to maintain masking. The medication dose, treatment duration, follow-up schedule beyond the primary outcome's stated timeframe, and details of the placebo are not reported in the registry record. Nor does the record describe recruitment procedures, site count, or the planned number of participants.
The primary outcome was the number of days to become free of narcotic pain medication. The registry lists pain-free days, days to return to normal activity, and days to return to normal fluid intake as secondary outcomes. It does not report a completed comparative analysis of these outcomes. The registry reports zero analyses, and its primary-outcome entry explains that no outcome data are being reported because of confidentiality concerns. Thus, the design and intended outcomes are identifiable, but the actual comparison is unavailable.
Although the registry includes arm-specific adverse-event entries, those entries do not overcome the stated absence of participant data. The record lists zero participants at risk and zero participants affected in both arms. Those fields cannot be read as evidence that participants experienced no adverse events, especially when the record also says no data are being reported for confidentiality reasons.
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.
Before assignment: The study was terminated due to low recruitment, since only one participant returned logbooks with data there are concerns with confidentiality therefore no data is being reported.
Overall Study
| Stage | 1: Post-operative Administration of Lansoprazole | 2: Placebo |
|---|---|---|
| STARTED | 2 | 0 |
| COMPLETED | 1 | 0 |
| NOT COMPLETED | 1 | 0 |
Reasons for not completing this period:
| Reason | 1: Post-operative Administration of Lansoprazole | 2: Placebo |
|---|---|---|
| Study was terminated due to poor compliance with returning logbooks by families. | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: The study was terminated due to low recruitment, since only one participant returned logbooks with data there are concerns with confidentiality therefore no data is being reported.
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: The study was terminated due to low recruitment, since only one participant returned logbooks with data there are concerns with confidentiality therefore no data is being reported.
| Characteristic | Unit | 1: Post-operative Administration of Lansoprazole | 2: Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | |
| Age, Categorical: <=18 years | — | — | — | |
| Age, Categorical: Between 18 and 65 years | — | — | — | |
| Age, Categorical: >=65 years | — | — | — | |
| Sex: Female, Male: Female | — | — | — | |
| Sex: Female, Male: Male | — | — | — | |
| Region of Enrollment: United States | participants | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as The Primary Outcome is the Number of Days to Become Free of Narcotic Pain Medication., measured over 2 weeks.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was the number of days required for a participant to become free of narcotic pain medication. It focuses on the duration of narcotic use during postoperative recovery, rather than directly measuring pain intensity. The registry gives a timeframe of 2 weeks, but does not report further details about how the endpoint was defined or assessed.
As a general statistical concept, a time-to-event endpoint records the time until a specified event occurs. In this trial, the event would be becoming free of narcotic pain medication. Such an endpoint can express how quickly participants reach a recovery milestone, but its interpretation depends on consistent event definitions, follow-up, and recording. The registry does not describe rules for participants who resumed medication, did not complete a logbook, or had no recorded event during the stated timeframe.
The endpoint was relevant to the trial's stated hypothesis because the registry describes a goal of reducing the amount of narcotic medication required for pain control. However, the endpoint is not itself a direct measure of pain. A difference in time to stopping medication would need to be interpreted alongside pain outcomes and the way medication use was managed. The registry lists days to become free of pain as a secondary outcome, but does not report its definition or results.
No participant-level endpoint values, group summaries, effect estimate, or uncertainty measure are reported. Consequently, the endpoint's observed distribution and any comparison between lansoprazole and placebo are not reported in the registry record. Its intended role can be explained, but the posted results do not support an estimate of the treatment contrast.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry does not report an outcome comparison. It records enrollment of 2 and explains that the trial was terminated because recruitment was low. The primary-outcome entry says that only one participant returned logbooks with data and that confidentiality concerns mean no data are being reported. With no posted outcome values or analysis, there is no reported estimate of the difference between postoperative lansoprazole and placebo in days to become free of narcotic pain medication.
There is consequently no reported effect estimate to describe as favoring either group, and no reported confidence interval or p-value for the primary outcome. The same applies to the named secondary outcomes: the registry lists recovery milestones involving pain, activity, and fluid intake, but does not report group results for them. The absence of an estimate is not evidence that the treatments had the same outcome. It means the registry record does not permit that comparison.
In general, an effect estimate describes the size and direction of a contrast between groups, while a confidence interval conveys the uncertainty around that estimate under the analysis assumptions. Without reported outcome data and a completed analysis, neither the size of the contrast nor its precision can be assessed. Statistical significance cannot be evaluated either. No conclusion about whether the observed results are compatible with a meaningful benefit, no difference, or a disadvantage can be drawn from the posted results.
The enrollment figure is also important to interpretation. The record reports 2 enrolled participants, but it does not report allocation counts, participant characteristics, or how many participants contributed data to each outcome. It states that one participant returned logbooks with data, yet those data are withheld for confidentiality reasons. That statement explains why results are absent; it does not disclose the participant's outcome or permit reconstruction of a group comparison.
The adverse-event entries list zero participants at risk and zero participants affected in each arm. Given the explicit statement that participant data are not being reported, these registry fields should not be interpreted as a demonstrated absence of adverse events. They do not provide an assessable safety comparison.
Overall, the record documents the intended randomized comparison and the reason results are unavailable. It does not establish whether lansoprazole changed postoperative pain, narcotic medication use, activity, or fluid intake. The appropriate statistical interpretation is therefore a lack of reportable comparative outcome evidence, not a positive or negative treatment finding.
9. Statistical Methods Explained
The registry identifies a randomized, triple-masked, parallel design. These labels describe broad features of the planned comparison, but they do not supply a full statistical analysis plan. The record does not report the randomization procedure, allocation ratio, masking roles, or procedures for analyzing outcomes. It lists zero analyses, and the primary-outcome description states that data are not reported because of confidentiality concerns.
What randomization is intended to do
In general, random assignment is used to make treatment groups comparable, on average, with respect to measured and unmeasured characteristics. It supports a fair comparison when allocation is implemented as planned and outcomes are collected and analyzed appropriately. A randomized label alone does not ensure that a useful comparison can be made: the number assigned to each arm, the outcomes observed, and the analysis all matter. In this record, arm-specific assignment counts and outcome summaries are not reported, so the success of the intended comparison cannot be assessed.
What masking can and cannot establish
In general, masking is intended to reduce the influence of expectations on treatment delivery, outcome assessment, or participant reporting. The record classifies the trial as triple-masked, but does not state who was masked or how masking was maintained. The designation therefore describes the registry's design classification; it does not document the practical success of masking. Because outcome data are withheld, the record also cannot show whether reporting or assessment was affected by knowledge of treatment assignment.
Understanding the primary outcome
The primary outcome is the number of days to become free of narcotic pain medication, with a timeframe of 2 weeks. As a general concept, time-to-event methods can be used when the outcome is the time until a defined event. Their interpretation depends on how the event and follow-up are specified, and on how incomplete follow-up is handled. The registry does not report whether a particular time-to-event model or other method was planned or used. It also does not describe censoring rules, the handling of missing logbooks, or the statistical summary intended for this outcome. No such method should be inferred from the endpoint wording alone.
The record names secondary outcomes concerning days to become free of pain, days to return to normal activity, and days to return to normal fluid intake. It does not report their operational definitions, measurement schedules, or analytic methods. Those details matter because different definitions or assessment schedules can change how an endpoint is interpreted. The fact that outcomes are named does not establish that their data were collected or analyzed.
Effect estimates and uncertainty
In general, a group comparison should communicate both an estimated effect and its uncertainty. A confidence interval is a range of values compatible with the observed data under the model and assumptions used; it helps readers assess precision rather than relying only on a significance test. A p-value, when used, measures how incompatible the data are with a specified null model under its assumptions. Neither statistic supplies the missing outcome data, and neither can be recovered from the registry description. No effect estimate, confidence interval, or p-value is reported for the primary or secondary outcomes.
Methods should also match the scale and distribution of the outcome. In general, time measures may have skewed distributions or observations that are incomplete by the end of follow-up. Appropriate methods depend on the actual data and prespecified analysis choices. The registry does not report distributions, model assumptions, diagnostic checks, or a chosen method, so it is not possible to judge whether any particular model would have been appropriate.
Planning and sample size
The registry reports low recruitment and enrollment of 2. It does not report a target enrollment, sample-size justification, or the assumptions used in planning. A sample-size calculation is a planning exercise based on specified assumptions; it is not evidence about the effect observed in a trial. Any planning illustration based on an observed effect would require a reported effect estimate, which is not available in the registry record. No planning calculation can replace the absent outcome comparison.
In general, a small observed sample can produce imprecise estimates, but precision cannot be quantified without outcome data and an analysis. It would be inappropriate to treat a hypothetical sample-size calculation as observed power or as evidence that a treatment effect exists. The key limitation in this record is not a reported estimate with a wide interval; it is that participant outcome data and comparative analyses are not reported.
What can be concluded about the statistical plan
The record establishes the design labels and intended outcomes, but not the analysis procedures. The statistical plan, any interim analyses, and any prespecified handling of missing observations are not reported in the registry record. There is no basis for attributing an analysis choice to the investigators or for judging whether the final analysis followed a protocol. Statistical explanations can clarify what methods would generally address, but they cannot fill in the trial's unreported methods or results.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary outcome and several secondary recovery outcomes. Considering multiple outcomes raises the general issue of multiplicity: when many comparisons are examined, the chance of a seemingly notable result arising by chance can increase. In general, a protocol or analysis plan may specify which outcome is primary, how secondary outcomes will be interpreted, and whether any adjustment or hierarchical procedure will be used. The registry does not report a multiplicity strategy, and there are no posted analyses to assess.
The primary endpoint is identified as days to become free of narcotic pain medication. Secondary outcomes concern days to become free of pain, return to normal activity, and return to normal fluid intake. The record does not explain whether these outcomes were prespecified in a detailed protocol, whether all were measured, or how results would have been prioritized. Any adjustment for multiple outcomes is not reported in the registry record. With no reported estimates or tests, multiplicity cannot be evaluated empirically.
Missing data are especially consequential. The record says that only one participant returned logbooks with data and that the study was terminated due to low recruitment. It also states that no data are being reported because of confidentiality concerns. It does not describe how many logbooks were expected, whether any other outcome measurements existed, or how missing observations would have been handled in an analysis. The participant's recorded outcome values are not available, so neither a complete-case analysis nor an alternative missing-data method can be assessed.
The record does not identify an intention-to-treat population, a per-protocol population, or another analysis population. In general, these populations define which randomized participants contribute to a particular analysis, and their definition can affect interpretation. No population-level results are reported. The registry's enrollment figure and its statement about a returned logbook do not supply an analyzable group comparison. Consequently, neither the impact of missing data nor the relationship between the randomized population and any analyzed population can be determined.
11. What the Result Does, and Does Not, Mean
The result of statistical interest would be a comparison of postoperative lansoprazole with placebo on the time until participants became free of narcotic pain medication. The registry does not report that comparison. It also does not report comparative results for the listed secondary outcomes. Therefore, there is no reported effect size, direction, or measure of precision from which to characterize the treatment contrast.
This absence should not be mistaken for evidence of no difference. A finding of no statistically detectable difference would require reported data and an analysis; neither is available. It should not be mistaken for evidence of benefit or harm either. The record establishes what the study intended to examine, not what happened to the participants in each group.
The stated reason for withholding results is confidentiality: only one participant returned logbooks with data. The registry says the study was terminated because recruitment was low and reports enrollment of 2. It does not give a group breakdown or participant-level characteristics. These details constrain interpretation and prevent an assessment of the outcomes, but they do not justify inventing or inferring the missing measurements.
In general, trial findings are interpreted in light of both effect size and precision, as well as study conduct and outcome measurement. Here, the precision of any possible effect cannot be assessed because no estimate or interval is reported. The registry also does not describe the statistical analysis plan, handling of missing data, or the exact endpoint assessment procedures. The design labels alone cannot resolve these uncertainties.
The adverse-event fields list zero participants at risk and zero affected in both arms. In light of the registry's explicit statement that participant data are not reported, these entries should not be taken as proof that no adverse events occurred. They do not provide a usable safety comparison. The defensible conclusion is limited: the registry records a randomized comparison that ended with low recruitment, while withholding participant outcomes for confidentiality reasons.
12. Why This Trial Matters Statistically
This trial illustrates an important distinction between a study's design and its evidentiary contribution. A randomized, triple-masked design describes an intended way to compare treatments. It does not itself provide evidence about the outcome. For a statistical interpretation, readers also need reported participant data, group comparisons, and an account of uncertainty. Those results are unavailable in this registry record.
The enrollment of 2 and the statement that only one participant returned logbooks with data make the reporting context central. The registry explains that confidentiality concerns prevented outcome reporting. That choice protects participant confidentiality, while also preventing readers from assessing the primary and secondary endpoints. The absence of results is not a statistical finding about the treatments; it is a limit on what can be learned from the record.
The case also highlights why outcome definitions and analysis plans matter. The primary outcome concerns time until freedom from narcotic pain medication, while the secondary outcomes describe pain, activity, and fluid-intake milestones. The record does not provide detailed measurement rules or analysis methods. Those details would be necessary to understand how outcomes were recorded and how group comparisons should be interpreted.
Finally, a small enrollment does not make a result automatically null, and an unreported result cannot be treated as a negative trial. Statistical inference depends on observed data and stated methods. Since neither comparative outcome estimates nor uncertainty measures are reported, the trial cannot answer its intended question from the posted results. Its statistical importance lies in showing how incomplete recruitment and confidentiality constraints can leave a randomized study without an assessable public outcome comparison.
13. 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 trial-specific limitation is that no participant outcome data are reported. The registry states that recruitment was low, the study was terminated, and only one participant returned logbooks with data. It gives confidentiality concerns as the reason that no data are being reported. This prevents assessment of the primary endpoint and the listed secondary outcomes.
The record reports enrollment of 2 but does not describe how participants were distributed between the lansoprazole and placebo arms. Participant characteristics, eligibility criteria, and the number contributing data to each outcome are not reported. Thus, the composition of the randomized population and the extent of outcome completion cannot be evaluated.
Details needed to understand treatment delivery are also absent. The registry does not report the lansoprazole dose, administration schedule, treatment duration, placebo details, or procedures used to implement randomization and masking. It does not describe how the endpoint was measured, how incomplete logbooks were handled, or which statistical methods were planned. These items are not reported in the registry record.
The record lists secondary outcomes but does not provide their detailed definitions or results. It reports zero analyses, with no effect estimates, confidence intervals, or p-values. It also does not report a sample-size justification, an interim-analysis plan, or a multiplicity strategy. The listed adverse-event fields show zero participants at risk and zero affected in each arm, but cannot establish the absence of events given the explicit statement that no participant data are being reported.
Together, these limitations mean that the registry can describe the intended study question and its termination, but cannot support a comparative assessment of efficacy, recovery, or safety outcomes.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: The Effects of Reducing Stomach Acid on Post-tonsillectomy Pain — NCT00472186.
- Registry record last updated 2021-12-06; status last verified 2021-11.
- Results first posted 2021-12-06.
- 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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17. Record Summary
NCT00472186 was a Phase 4, randomized, triple-masked, parallel-group study sponsored by Boston Children's Hospital. It compared postoperative lansoprazole with placebo after tonsillectomy. The primary outcome was days to become free of narcotic pain medication, with a stated timeframe of 2 weeks. Listed secondary outcomes concerned pain, return to normal activity, and return to normal fluid intake.
The record reports enrollment of 2, a start date of 2008-06, primary completion in 2011-02, and terminated status. It states that termination followed low recruitment and that only one participant returned logbooks with data. Because of confidentiality concerns, no participant outcome data are reported. The registry lists zero analyses and does not report a comparative treatment effect or its precision. The intended clinical comparison is clear, but the posted results do not establish how the groups differed.