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 Detection of Barrett s Esophagus in Patients Without GERD Symptoms (NCT04880044), a na na study. The primary outcome is Positive Predictive Value (PPV) of EC/EG in a Non-GERD Population That Has Three or More Non-GERD Risk Factors for BE..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04880044 |
| Phase | NA |
| Condition | Barrett's Esophagus |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 132 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Case Comprehensive Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
People without GERD symptoms who have three or more non-GERD risk factors for Barrett’s esophagus and are considered at risk. The primary endpoint population is narrower: it includes only participants who underwent EGD and met the criteria for the PPV calculation.
Intervention
EsoCheck/EsoGuard (EC/EG): an EsoCheck procedure, followed by testing of the EC sample with the EsoGuard assay. Participants also completed a questionnaire about reflux symptoms.
Comparator
There is no randomized or like-for-like control group. EGD is part of the diagnostic pathway for participants with positive EC/EG results, rather than a separate randomized treatment arm.
Primary question
Among eligible participants with positive EC/EG results who underwent EGD, what proportion also had a positive EGD result? The registry defines this as the positive predictive value of EC/EG in the stated non-GERD, higher-risk population.
The study’s stated purpose is to develop a method for detecting Barrett’s esophagus with a new office-based diagnostic test. Its primary question is about agreement between a positive EC/EG result and a subsequent positive EGD result in the specified population. It is not a question about whether a treatment improves health outcomes, and it is not a comparison of EC/EG against a randomized control group.
The distinction between the broader study population and the endpoint population matters. The registry says that only participants who underwent EGD and met the PPV criteria were included in the endpoint calculation; 83 participants were not included because they did not meet those criteria. The record does not provide the PPV estimate, its confidence interval, or the underlying counts. Consequently, the clinical question is clear, but the posted registry results do not show the answer numerically.
3. Trial Design
This is a completed, single-group diagnostic-test study sponsored by Case Comprehensive Cancer Center. Its recorded enrollment is 132. The registry lists the phase and allocation as NA and masking as none. The study began on 2022-01-05 and had a primary completion date of 2025-02-25. Its condition is Barrett’s esophagus.
The recorded study pathway includes a questionnaire about reflux symptoms and an EsoCheck procedure. The sample from that procedure is tested with the EsoGuard assay. Participants with positive assay results are requested to complete standard-of-care upper endoscopy; the primary endpoint description likewise says that participants with positive EC/EG results undergo subsequent EGD. EGD serves as the endoscopic result used in the PPV definition, not as a control arm assigned in a randomized comparison.
The primary endpoint concerns the PPV of EC/EG in people without GERD symptoms who have three or more non-GERD risk factors for Barrett’s esophagus. The registry states that participants at risk are offered EC/EG. The endpoint population includes only those who underwent EGD and met the calculation criteria. The record says 83 participants were not included for not meeting these criteria, but it does not give the endpoint numerator or denominator.
Because the study has one group and no randomized allocation, it cannot provide a randomized between-group estimate of diagnostic performance or treatment effect. The listed sample-size assumptions describe a planning illustration with equal allocation between two arms; they do not describe this single-group study’s design. The trial’s own sample-size justification, if any, is not reported in the registry record. Further protocol details, including any interim analyses, are also 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 | EC/EG & EGD |
|---|---|
| STARTED | 132 |
| COMPLETED | 124 |
| NOT COMPLETED | 8 |
Reasons for not completing this period:
| Reason | EC/EG & EGD |
|---|---|
| Physician Decision | 8 |
Analysis population for the primary outcome, as defined in the registry: Only participants who underwent EGD and meet criteria for PPV calculation were included. 83 participants were not included, as they did not meet these criteria.
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 | EC/EG & EGD |
|---|---|---|
| Participants analysed | 132 | |
| Age, Customized: 40-49 | Participants | 0 |
| Age, Customized: 50-59 | Participants | 62 |
| Age, Customized: 60-69 | Participants | 52 |
| Age, Customized: 70-79 | Participants | 16 |
| Age, Customized: 80-89 | Participants | 2 |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 123 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 121 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 9 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 3 |
| Race (NIH/OMB): White | Participants | 125 |
| Race (NIH/OMB): More than one race | Participants | 1 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Positive Predictive Value (PPV) of EC/EG in a Non-GERD Population That Has Three or More Non-GERD Risk Factors for BE., measured over Up to 2 months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | Percentage of screened participants |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the positive predictive value of EC/EG in a non-GERD population with three or more non-GERD risk factors for Barrett’s esophagus. In the registry’s definition, the numerator is the number of participants whose EC/EG result and EGD result are both positive. The denominator includes those participants plus participants with a positive EC/EG result and a negative EGD result. In plain terms, PPV describes how often a positive test result is accompanied by a positive result on the specified reference examination among the participants included in the calculation.
PPV is useful for interpreting what a positive test means within a particular population and diagnostic pathway. It is not an all-purpose property of a test: the population, eligibility rules, and confirmation process define the group to which the estimate applies. Here, the endpoint applies only to participants who underwent EGD and met the stated criteria. It does not directly describe test performance among every enrolled participant or among people outside the registry’s defined population.
The endpoint is recorded as a percentage of screened participants, with a 95% confidence interval and a timeframe of up to 2 months. However, the registry record does not report the PPV value, its confidence interval, or the counts used to calculate it. The endpoint’s meaning can therefore be described, but its numerical estimate and precision cannot be assessed from the posted registry results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a focused diagnostic question: whether a positive EC/EG result is followed by a positive EGD result in a specified group of people without GERD symptoms who have three or more non-GERD risk factors for Barrett’s esophagus. The endpoint is PPV, which addresses the proportion of qualifying positive EC/EG results that also have a positive EGD result. That definition is important because it sets the scope of any interpretation: the endpoint is not a general measure of every aspect of diagnostic accuracy.
The posted record does not report a PPV estimate, a 95% confidence interval, or the counts contributing to that endpoint. It therefore does not support a numerical statement about the proportion of positive EC/EG results confirmed by EGD, or how precisely that proportion was estimated. The primary outcome’s measurement unit and time frame are listed, but those details do not substitute for the missing result.
The endpoint population was selected using EGD completion and eligibility for the PPV calculation. The record states that 83 participants were not included because they did not meet those criteria. This means the endpoint does not represent all 132 enrolled participants. The registry does not give further detail about the reasons each participant failed to meet the criteria, so it is not possible to tell from the record how those exclusions arose or how they might relate to test results.
As a general statistical point, an estimate is easier to judge when both its value and uncertainty are reported. A confidence interval conveys a range of values compatible with the data under the statistical method used; its width is informative about precision. Since the interval and the estimate are not reported, neither the size of the PPV nor its precision can be evaluated. No conclusion about the performance of the test should be drawn from the absence of those results.
The single-group design also limits what can be learned comparatively. There is no randomized control group, and the record does not describe a randomized comparison. EGD is used in the endpoint pathway for qualifying participants, rather than serving as a concurrently randomized comparator. The study can be framed as an evaluation of a diagnostic pathway, but the posted outcome information is insufficient to quantify its primary result or compare it with another strategy.
The registry lists 132 participants at risk for serious adverse events and 132 at risk for other adverse events, with zero affected in each category and zero deaths. These are the posted safety counts. They do not fill the gap in the diagnostic endpoint results, and the record does not provide additional detail about adverse-event collection or reporting. The sponsor’s analysis cannot be compared with a recalculation because no primary endpoint result or underlying counts are posted.
9. Statistical Methods Explained
The registry describes a single-group diagnostic study, not a randomized comparison. That design determines the kind of statistical question the primary endpoint can answer. The endpoint is a conditional proportion: among participants with a positive EC/EG result who also meet the stated criteria and undergo EGD, it concerns the fraction with a positive EGD result. It does not estimate a difference between randomized groups.
What does positive predictive value describe?
Positive predictive value, or PPV, is the proportion of positive results from an index test that are also positive under the specified reference procedure in the population being evaluated. The index test in this record is EC/EG, and the reference result used in the endpoint definition is EGD. The registry’s formula counts participants positive on both procedures in the numerator. Its denominator adds participants who were EC/EG positive but EGD negative. Participants with a negative EC/EG result are not part of that denominator.
This conditional definition has practical statistical consequences. PPV answers a question about positive test results; it does not, by itself, describe the fraction of all people with the condition who test positive. Nor does it supply the false-negative rate or an overall accuracy measure. Those quantities require their own definitions and data. The registry names PPV as the primary endpoint and does not report the other measures or their results.
Why does the endpoint population matter?
The record says the primary outcome includes only participants who underwent EGD and met the criteria for PPV calculation. It also says that 83 participants were not included because they did not meet those criteria. Thus, the endpoint is defined for an eligible subset, not simply for everyone enrolled. Statistical interpretation should preserve that denominator rather than treating the enrolled group as the endpoint population.
As a general consideration, when confirmation by a reference procedure is available only for a subset, the subset’s results may not represent people without confirmation. The pattern of who receives or completes verification can matter to an estimate. The registry record does not provide enough detail to determine whether this concern affected the study’s result, and no numerical result is available for assessment. It is therefore appropriate to describe the eligibility restriction without assuming either that it biased the estimate or that it did not.
What would a confidence interval add?
The endpoint specifies a 95% confidence interval. In general, a confidence interval expresses uncertainty around an estimate under the method used to calculate it. A narrower interval indicates greater precision than a wider interval, while neither interval width nor the estimate alone establishes that a diagnostic strategy is clinically useful. Interpretation also depends on the population, endpoint definition, and study conduct.
The registry does not report the PPV estimate or its confidence interval. As a result, neither the observed proportion nor its uncertainty can be assessed. The number of eligible participants, the positive-result counts, and the statistical procedure used to construct the interval are also not reported in the registry record. No interval can be reconstructed from the enrollment and exclusion information alone.
How should the design be distinguished from planning assumptions?
The study is recorded as single group, with allocation listed as NA and no masking. The sample-size assumptions describe a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Those assumptions are not a description of the recorded single-group design. The illustration is not an observed outcome and is not observed power. The record does not state the study’s own sample-size justification or provide numerical planning results in the registry record used for this account.
As a general statistical concept, power calculations are design planning tools that depend on assumptions about the effect to detect, variability, allocation, and analysis. A planning calculation cannot establish what the study observed. Here, the stated two-arm allocation assumption does not match the recorded single-group model, so it should not be read as evidence that the trial actually randomized participants between two arms.
What can be inferred from the posted analysis information?
The registry lists zero analyses. That means the record does not supply analysis details or an inferential result for the primary endpoint in the information summarized. It does not establish which statistical methods may have been used outside the registry record. In particular, the statistical model, handling of missing endpoint data, and any adjustment or subgroup approach are not reported in the registry record.
The distinction between what is defined and what is reported is central. The endpoint formula and target population are specified, but the estimate, interval, underlying counts, and analysis details are absent. Statistical interpretation can explain the intended measure and its limitations, but it cannot fill in those missing results.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies a primary endpoint and lists two outcome measures, but the record lists zero analyses. It does not report a multiplicity plan, such as whether multiple outcomes or analyses were adjusted for when interpreting statistical evidence. Any such plan is not reported in the registry record. Without analysis results and a stated plan, the impact of multiplicity on inference cannot be assessed.
The primary endpoint population is restricted to participants who underwent EGD and met the criteria for PPV calculation. The record says 83 participants were not included because they did not meet those criteria. It does not provide a complete account of missing observations, the reasons for non-inclusion, or how such cases were handled in the analysis. Not meeting endpoint criteria is not necessarily the same as having a missing value, so those categories should not be conflated.
The number of participants included in the final PPV calculation, the numerator and denominator, and any approach to missing or indeterminate test results are not reported in the registry record. The record also does not say whether analyses used an intention-to-diagnose, complete-case, or other analysis population. Those details matter because an endpoint estimate applies to the participants and rules used to produce it. In their absence, the reported population restriction can be described, but its statistical consequences cannot be quantified.
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 |
|---|---|---|---|
| EC/EG & EGD | 0 | 132 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| EC/EG & EGD | 0 of 132 |
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 |
|---|---|
| EC/EG & EGD | 0 of 132 |
The registry reports one group, EC/EG & EGD. Among the 132 participants listed as at risk for serious adverse events, zero were affected. Among the 132 listed as at risk for other adverse events, zero were affected. The death count is zero, and no top serious adverse-event terms are listed.
These figures describe what the registry reports for the stated group and categories. They do not indicate that no events of any kind occurred unless those events fall within the categories and reporting definitions represented by these fields. The record does not provide further detail on adverse-event definitions, collection procedures, or the period used for safety monitoring, so those aspects are not reported in the registry record.
As a general statistical point, a zero count is a description of the observed record, not proof that the underlying event risk is zero. The safety counts should also be kept separate from the primary diagnostic endpoint: they do not provide the missing PPV result or its confidence interval. No comparative safety conclusion is available from this single-group study record.
12. What the Result Does, and Does Not, Mean
The registry record establishes the study’s intended diagnostic question and the definition of its primary endpoint. It describes a single-group pathway in which participants complete a questionnaire, undergo an EsoCheck procedure, and have the sample tested by EsoGuard; those with positive results are requested to complete standard-of-care upper endoscopy. The endpoint is the PPV of EC/EG in the defined non-GERD population with three or more non-GERD risk factors for Barrett’s esophagus.
The posted record does not report the primary endpoint estimate, its 95% confidence interval, or the counts used to calculate it. Therefore, it does not establish numerically how often positive EC/EG results were accompanied by positive EGD results in the eligible endpoint population. The absence of a reported result is not evidence of a positive, negative, or inconclusive finding. It is a limit on what can be concluded from the registry information.
The result, if reported, would pertain to the population and verification process specified for the endpoint. It would not automatically apply to all enrolled participants, to people outside the stated risk criteria, or to other clinical settings. The record says that 83 participants were not included because they did not meet the PPV criteria, reinforcing that the endpoint denominator is narrower than enrollment.
This study is not a randomized comparison of EC/EG against an alternative strategy. EGD functions as the reference examination in the described endpoint pathway. Accordingly, the design does not establish a comparative treatment effect, and the posted safety counts do not establish comparative safety. The record’s zero affected counts are descriptive for the listed categories and group; they do not replace a full account of event definitions or monitoring.
As a general principle, diagnostic performance is best interpreted with its estimate, uncertainty, population, reference standard, and analysis rules together. Several of those elements are not reported in the registry record. The proper interpretation is therefore limited: the study sought to evaluate PPV for a specified diagnostic pathway, but the posted results do not allow the numerical performance or its precision to be judged.
13. Why This Trial Matters Statistically
This study illustrates why a diagnostic endpoint needs to be read together with its population definition and verification pathway. PPV is not simply a property of a test in isolation: it describes positive EC/EG results in the group eligible for the calculation, using EGD as the reference result. In this record, eligibility includes having three or more non-GERD risk factors, and the primary outcome includes only those who underwent EGD and met the stated criteria.
The distinction between enrollment and endpoint population is especially important. The study enrolled 132 participants, while the record says 83 were not included in the PPV calculation because they did not meet its criteria. Those figures should not be treated as interchangeable denominators. The record does not report the final endpoint denominator, which prevents readers from assessing how much information contributed to the primary estimate.
It also demonstrates the value of complete outcome reporting. A clearly defined endpoint is not enough to assess evidence: the estimate, confidence interval, contributing counts, and analysis approach are needed to judge both the magnitude and precision of a result. Those numerical primary results are not reported in the registry record. As a consequence, the stated question can be explained, but its empirical answer cannot be evaluated from the posted information.
Finally, the study’s single-group diagnostic design should not be confused with a randomized comparison. The registry’s planning assumptions refer to equal allocation between two arms, whereas the recorded model is single group. Keeping design details separate from planning illustrations prevents a hypothetical calculation from being mistaken for the study’s actual allocation or observed evidence.
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 for interpreting the primary endpoint is that the registry record does not report the PPV estimate, its 95% confidence interval, or the counts underlying the calculation. Without these, the magnitude and precision of the primary result cannot be assessed. The record also lists zero analyses, and does not report the statistical method used to analyze the endpoint.
The endpoint is restricted to participants who underwent EGD and met the PPV criteria. The registry says 83 participants were not included for not meeting those criteria, but does not give more detail about their individual eligibility or outcomes. The final denominator and any handling of missing or indeterminate test results are not reported in the registry record. This limits assessment of how the endpoint population relates to the enrolled group.
The study has a single-group design and no randomized comparator. EGD is part of the verification pathway for positive EC/EG results, rather than a separately randomized comparison. The record therefore does not support a randomized comparative estimate. Further details about diagnostic procedures and the conduct of the study beyond the listed pathway are not reported in the registry record.
The registry lists sample-size assumptions for a planning illustration using equal allocation between two arms and a normal approximation, but the recorded study model is single group. The study’s own sample-size justification is not reported in the registry record. Multiplicity handling, interim analyses, analysis-population rules, and missing-data methods are also not reported. These limitations concern the information available in the registry; they should not be interpreted as proof that the study did not address these matters elsewhere.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Detection of Barrett s Esophagus in Patients Without GERD Symptoms — NCT04880044.
- Registry record last updated 2026-03-10; status last verified 2026-02.
- Results first posted 2026-03-10.
- 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.
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18. Record Summary
NCT04880044 is a completed, single-group diagnostic study sponsored by Case Comprehensive Cancer Center. Its recorded enrollment is 132, and its primary completion date is 2025-02-25. The study evaluates EsoCheck/EsoGuard in people without GERD symptoms who have three or more non-GERD risk factors for Barrett’s esophagus, with EGD used in the diagnostic pathway for positive results.
The primary endpoint is PPV among participants who underwent EGD and met the calculation criteria. The registry says 83 participants were not included because they did not meet those criteria. The numerical PPV result, its confidence interval, underlying counts, and analysis details are not reported in the registry record. Safety reporting lists zero serious adverse events, zero other adverse events, and zero deaths among the participants recorded at risk in the single group.