Does Intensive Acid Suppression Reduce Esophageal Inflammation and Recurrent Barrett's Esophagus Following Ablation?: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Does Intensive Acid Suppression Reduce Esophageal Inflammation and Recurrent Barrett's Esophagus Following Ablation? (NCT01093755), a randomized phase 4 study. The primary outcome is Change in Inflammation Biomarker Tissue PGE2 Level.

2. Clinical Question

The clinical rationale in the registry record links acid suppression with esophageal inflammation and the possibility of recurrent intestinal metaplasia following ablation. The stated hypothesis focuses on inflammatory mediators; the listed primary endpoint is change in PGE2, not a reported result for recurrence. The record does not establish whether a measured change in this biomarker corresponds to a change in recurrence. That relationship would require outcome data and an analysis connecting the measures, neither of which is reported in the registry record.

3. Trial Design

The registry record describes a completed Phase 4, randomized, parallel-group trial sponsored by Mayo Clinic. It lists enrollment of 30 and reports a start date of 2010-03 and primary completion date of 2014-11. Masking is listed as none, so the record describes the trial as unmasked. It does not report the method used to generate the random allocation sequence, how allocation was concealed, or whether any other personnel were masked.

The two listed drug interventions were dexlansoprazole and omeprazole. The dexlansoprazole arm description specifies 60-90 mg/day for 6 months. The omeprazole description specifies 20mg/day for a minimum of 6 weeks, with a possible increase by 20mg twice if symptomatic. The record does not report actual treatment duration by participant, adherence, dose changes, or whether treatment was discontinued.

The primary endpoint was change from baseline in esophageal tissue biopsy PGE2 level, measured by enzyme immunoassay. The timeframe lists 3 months and 6 months. The registry record does not specify a single primary time point or give values for either time point. It lists 2 outcome measures and 4 analyses, but does not describe the other outcome measure or identify the analyses in the information available for interpretation.

Randomization can support a fair comparison when allocation and follow-up are handled appropriately, but the record does not contain enough detail to assess these processes. It also does not report the planned sample-size justification, protocol deviations, or the statistical analysis plan. These omissions do not establish that procedures were absent; they mean their details are 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

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Change in Inflammation Biomarker Tissue PGE2 Level, measured over 3 months, 6 months.

The primary endpoint is change from baseline in esophageal tissue prostaglandin E2, or PGE2, measured from biopsy tissue by enzyme immunoassay. Its unit is nanograms/gram of tissue. The listed timeframe includes 3 months and 6 months. PGE2 is described in the record as an inflammation biomarker, so measuring its change provides a way to assess whether tissue biomarker levels differ over time between the treatment groups.

General: A continuous endpoint such as a biomarker level can be described by its mean and standard deviation. The mean represents the average measured level or change in a group; the standard deviation describes how dispersed individual observations are around that average. Neither measure by itself establishes whether groups differ beyond what could plausibly arise from sampling variation. A treatment comparison needs an estimated between-group contrast and an account of its uncertainty, such as a confidence interval, alongside any inferential test.

The registry record names the endpoint's summary parameter as a mean and its dispersion as a standard deviation. However, it does not report baseline or follow-up PGE2 values, mean changes, standard deviations, or a between-group estimate. Thus, the endpoint definition can be described, but the magnitude and precision of any observed treatment contrast cannot be evaluated from the registry record. The stated clinical interest in recurrent Barrett's esophagus does not make recurrence the primary endpoint listed for this analysis.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record identifies the primary endpoint as a continuous measure summarized by a mean with standard deviation. It is change from baseline in esophageal tissue PGE2 level, with measurements described at 3 months and 6 months. No numerical endpoint results or statistical tests are reported, so the methods can be explained in general terms without attributing unreported procedures to this trial.

What does a mean change represent?

General: A change-from-baseline outcome compares a participant's follow-up measurement with that participant's starting measurement. Group means can then describe the average change among participants with available measurements. A treatment comparison may estimate the difference between the average changes in the randomized groups. The exact calculation and model matter: the registry record does not report whether the analysis used raw changes, a baseline-adjusted model, or another approach. It also does not provide the mean changes or the estimated contrast.

A standard deviation describes variation among observations within a group; it is not the uncertainty of the group mean and is not a treatment-effect confidence interval. The amount of uncertainty in a group mean depends on the variability and the number of observations contributing to it. The record names standard deviation as the dispersion measure but does not provide the values, endpoint-specific sample counts, or interval estimates. Readers therefore cannot assess the spread of PGE2 changes or the precision of a comparison.

Why does the analysis model matter?

General: Statistical models make assumptions about the outcome and its variability. For a continuous outcome, an analysis may compare means under assumptions about the distribution of errors and the relation between baseline and follow-up measurements. If measurements are skewed, contain outliers, or have different variability between groups, a simple model may not describe them well. Repeated measurements on the same participant are related, so an analysis that uses measurements at multiple time points must account for that dependence or specify a separate comparison for each time point. The registry record does not identify the model used, its assumptions, or how the observations at the two time points were handled.

General: Over-dispersion means that observed variability is greater than a model expects. When a model understates variability, standard errors may be too small and confidence intervals too narrow; this can make evidence appear more precise than it is. This concept is not a finding about this trial. The record does not report a dispersion assessment or any indication that over-dispersion was relevant to its analysis.

What do the planning assumptions mean?

The record's sample-size planning description specifies a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. These are planning assumptions for an illustration, not a report of the trial's original design justification. The numerical planning outputs and the observed effect used for those calculations are not reported in the registry record.

General: A sample-size calculation estimates how many participants may be needed to detect a chosen effect under stated assumptions about variability, allocation, and type I error. Changing the effect assumed for planning changes the required sample size. Such planning figures are not observed power and do not show whether a completed trial detected an effect. The registry record does not report the rationale for enrolling 30 participants, the original target enrollment, or whether the trial reached its intended enrollment.

The planning description calls for participants per arm for non-time-to-event outcomes. This endpoint is continuous, rather than time-to-event. The stated planning illustration should not be confused with the actual randomized sample, nor should it be treated as proof of the precision of the observed primary-endpoint estimate. No estimate or interval for that endpoint is reported.

What can be inferred from the reported analysis count?

The registry record lists 4 analyses but does not describe their methods, outcomes, populations, or time points. It is not possible to determine whether they represent different statistical models, endpoint time points, subgroups, or other comparisons. They should not be assumed to be independent analyses or to follow any particular prespecified plan.

General: Statistical interpretation is strongest when the analysis population, outcome definition, model, handling of missing observations, and multiplicity approach are clearly specified. An estimate should be read together with its uncertainty and the analysis context. In this record, the endpoint definition is available, but those supporting analysis details and the numerical comparison are not reported. Accordingly, no claim about the effect's size, statistical significance, or precision can be drawn from the endpoint description alone.

10. Multiplicity, Missing Data and Analysis Populations

The primary endpoint is listed at 3 months and 6 months. Reporting several time points can create a multiplicity question: repeated opportunities to test for a difference can increase the chance of at least one apparently notable result under a null hypothesis. General: A prespecified analysis plan may address this by defining a primary time point, adjusting comparisons, or otherwise explaining how multiple tests will be interpreted. The registry record does not identify a primary time point within the stated timeframe or report a multiplicity strategy. It does not report the PGE2 results or tests at either time point.

The record lists 4 analyses and 2 outcome measures, without enough detail to identify the analyses or all endpoints. It does not report whether the analyses were prespecified, whether any were exploratory, or whether adjustments were made across endpoints, time points, or other comparisons. No particular adjustment method can therefore be attributed to the trial.

The analysis population for the primary endpoint is also not reported in the registry record. There is no description of whether results were intended to include all randomized participants, participants who received treatment, or participants with available measurements. The record does not say how missing baseline or follow-up biopsies, withdrawals, treatment changes, or protocol deviations were handled. It does not report the number of endpoint observations available at either time point.

General: Missing outcome data can affect both the size and reliability of an estimated treatment contrast, especially when the reasons for missingness are related to treatment or outcome. Statistical approaches make assumptions about the unobserved measurements; those assumptions should be stated and sensitivity analyses may help assess their influence. The registry entries do not identify an approach or sensitivity analysis. These are reporting gaps, not evidence that missing data occurred or that a particular method was or was not used.

11. Safety Results

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

Other (non-serious) adverse events

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

The registry record reports no serious adverse events in the listed groups: 0 among 16 participants at risk in the dexlansoprazole group and 0 among 14 participants at risk in the omeprazole group. It also reports 0 other adverse events among 16 participants at risk in the dexlansoprazole group and 0 among 14 participants at risk in the omeprazole group. These are the counts recorded for the listed categories and groups.

These figures do not establish that no adverse events of any kind occurred, or that treatment groups had equivalent safety. The record does not provide event terms for non-serious events, and it lists no top serious-event terms. Death counts are not reported in the registry record. The record also does not describe how adverse events were defined, collected, followed over time, or whether all randomized participants were included in the safety assessment.

General: An observed count of zero is a description of the recorded data, not proof that the underlying event risk is zero. Safety comparisons depend on the number of participants observed, length and completeness of follow-up, and event definitions. With the limited counts and reporting detail available, the figures should be read narrowly as the adverse-event counts listed, rather than as a comprehensive safety comparison.

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

The registry record establishes the trial's stated question: whether dexlansoprazole compared with omeprazole changes esophageal tissue PGE2 after ablation. It identifies the primary biomarker endpoint, its assay, its unit, and the planned assessment times of 3 months and 6 months. It also provides treatment descriptions and reports enrollment of 30 in a completed randomized parallel-group trial.

It does not report the primary endpoint values, the mean changes in either group, a between-group estimate, confidence intervals, or p-values. As a result, the direction and size of any difference and the precision of the comparison are unknown from the registry record. The investigators' hypothesis is not an outcome finding. The record's description of a potential link between inflammation and recurrent intestinal metaplasia likewise does not establish whether recurrence differed between groups.

General: A biomarker may be useful for studying a biological process, but a change in a biomarker and a change in a clinical outcome are distinct findings. To interpret a biomarker as evidence about recurrence would require reported recurrence data and a clearly described analysis of that outcome. Such results are not reported in the registry record.

The adverse-event record lists zero serious and zero other events in each group's stated at-risk count. Those entries are not a substitute for a complete safety analysis, and death counts are not reported. The trial's enrollment and completion status also do not reveal whether all participants contributed endpoint data or how missing values were handled.

Accordingly, the defensible conclusion is about what was registered and what is missing: a randomized comparison with a defined PGE2 endpoint is described, but its numerical primary result and its uncertainty are not reported. No conclusion about the treatment effect or recurrence outcome can be drawn from the details available.

13. Why This Trial Matters Statistically

This trial is statistically notable for the distinction between a registered clinical hypothesis and a reportable treatment-effect estimate. The record gives the intended contrast between two acid-suppression regimens and identifies a tissue biomarker endpoint, but it does not report the numerical result needed to evaluate that contrast. A well-defined outcome is necessary for interpretation; it is not a substitute for an estimate, uncertainty interval, or transparent analysis.

The endpoint is specified at 3 months and 6 months, which raises an important general issue about how multiple time points are handled. If each is analyzed separately, interpretation depends on which comparisons were prespecified and whether multiplicity was considered. Since that information is not reported, readers cannot determine how to weigh any time-specific test. In this case, no time-specific result is reported either.

The record also illustrates why analysis-population and missing-data details matter. Enrollment of 30 does not tell readers how many participants had usable biopsy measurements at each assessment or how missing observations were treated. Without those details and the corresponding estimates, neither the consistency nor the precision of the primary comparison can be judged.

The planning description is another useful distinction: an illustrative sample-size calculation based on an observed effect is not the trial's original sample-size justification and is not observed power. The registry record states assumptions for planning illustrations but does not report numerical outputs. The actual rationale for enrollment is not reported in the registry record.

These limitations are statistically important because they separate study design, outcome definition, planning assumptions, and observed evidence. The design and endpoint can be described, while the treatment effect, its precision, and its relation to recurrence remain unreported.

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 registry record does not provide the numerical primary endpoint results, so neither the direction nor magnitude of change in tissue PGE2 can be assessed. It gives no between-group estimate, confidence interval, standard error, or p-value. This prevents evaluation of both statistical precision and the range of effects compatible with the data.

The endpoint timeframe includes 3 months and 6 months, but a primary time point is not identified. The record lists 4 analyses and 2 outcome measures without explaining their contents or methods. It does not report whether multiplicity was addressed, whether analyses were prespecified, or how results across time points were interpreted.

The analysis population and endpoint-specific sample counts are not reported. The registry record also does not describe missing-data handling, treatment adherence, actual exposure duration, dose changes, or protocol deviations. Although treatment descriptions include a possible omeprazole dose increase for symptoms, the number of participants whose dose changed is not reported. The randomized allocation method and concealment procedures are also not described.

The registry's stated rationale mentions possible recurrence of intestinal metaplasia after ablation, but recurrence results are not included in the details available for interpretation. No conclusion about that clinical outcome or its relation to PGE2 can therefore be made. Safety reporting is limited to the listed event counts; event definitions, follow-up duration for safety, and death counts are not reported in the registry record.

These are limitations of what the registry record reports. They should not be taken as evidence that an analysis, follow-up procedure, or safety process did not occur; its details are simply not reported in the registry record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Does Intensive Acid Suppression Reduce Esophageal Inflammation and Recurrent Barrett's Esophagus Following Ablation? — NCT01093755.
• Registry record last updated 2016-03-17; status last verified 2016-02.
• Results first posted 2016-03-17.
• 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 trial sponsored by Mayo Clinic, with no masking and enrollment of 30. It lists dexlansoprazole and omeprazole as the interventions and specifies change from baseline in esophageal tissue PGE2 as the primary endpoint, measured by enzyme immunoassay at 3 months and 6 months.

The treatment descriptions specify dexlansoprazole 60-90 mg/day for 6 months and omeprazole 20mg/day for a minimum of 6 weeks, with a possible increase by 20mg twice if symptomatic. The primary endpoint results, analysis methods, analysis population, missing-data approach, and multiplicity strategy are not reported in the registry record. The listed adverse-event counts are zero for serious and other events in both groups; death counts are not reported. The registry entries therefore establish the study question and design features, but do not permit interpretation of the primary treatment comparison or recurrence outcome.