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 Pilot Study Evaluating the Safety and Efficacy of a Patient-Specific Enteroatmospheric Fistula Isolation and Management Device Independent of Negative Pressure Wound Therapy (NCT04978090), a na na study. The primary outcome is Change in Inpatient Participant Pain Rating.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04978090 |
| Phase | NA |
| Condition | Fistula, Abdominal Injury, Negative Pressure Wound Therapy |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Andrew Bernard |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled two participants with enteroatmospheric fistulas. The registry record says their data cannot be presented because the participants could reasonably be identified given the low enrollment. The conditions listed also include abdominal injury and negative pressure wound therapy, but further eligibility details are not reported in the registry record.
Intervention
Participants received a patient-matched, 3D-printed enteroatmospheric fistula management device. The stated aim was to isolate fistula effluent independently of negative pressure wound therapy. The study also aimed to assess dressing changes, the time required for them, management costs, and ease of use.
Comparator
This was a single-group study, not a randomized comparison. The registry record does not describe a separate control group or a like-for-like comparator. Consequently, the design does not support a direct comparison of the device with another treatment or management approach.
Primary question
The primary outcome was change in inpatient participant pain rating. Participants were to rate pain daily from admission to discharge, up to 1 year, on a scale from 1 to 10, with 10 indicating more pain. The registry record does not present the pain observations or an estimated change.
3. Trial Design
This completed pilot study evaluated a custom-fitted device intended to isolate enteroatmospheric fistula effluent independently of negative pressure wound therapy. The intervention is described as a 3D-printed, participant-matched device. The registry record lists one study group and an enrollment of two participants. It identifies Andrew Bernard as the sponsor.
The registry classifies the study as single group, with allocation recorded as NA and masking as none. This was not a randomized trial and did not include a like-for-like control comparison. The study phase is recorded as NA. The recorded start date is 2021-07-01, and the primary completion date is 2022-09-16. The status is COMPLETED.
The stated study aims included assessing the device’s efficacy and its effects on dressing changes, time required for dressing changes, management costs, and ease of use. Listed secondary outcomes include infection rates, number of observed leakages, length of stay, fistula resolution time, and complication occurrences. The registry lists 17 outcome measures, but outcome results beyond the primary outcome description are not reported in the registry record.
The primary outcome was change in inpatient participant pain rating, assessed daily from admission to discharge, up to 1 year. The record explains that participant data cannot be presented because the low enrollment could make the participants reasonably identifiable. It lists no analyses. Detailed eligibility criteria, device-use procedures, follow-up procedures beyond the stated pain timeframe, and the statistical analysis plan 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
| Stage | Enteroatmospheric Fistula (EAF) Management Solution |
|---|---|
| STARTED | 2 |
| COMPLETED | 0 |
| NOT COMPLETED | 2 |
Reasons for not completing this period:
| Reason | Enteroatmospheric Fistula (EAF) Management Solution |
|---|---|
| unable to adequately fit device | 2 |
Analysis population for the primary outcome, as defined in the registry: Two participants were enrolled in this study. Due to the possibility that the participants could reasonably be identified due to low enrollment, data cannot be presented.
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 | Enteroatmospheric Fistula (EAF) Management Solution |
|---|---|---|
| Participants analysed | 2 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 |
| Age, Categorical: >=65 years | Participants | 1 |
| Sex: Female, Male: Female | Participants | 2 |
| Sex: Female, Male: Male | Participants | 0 |
| 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 | 0 |
| Race (NIH/OMB): White | Participants | 2 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Inpatient Participant Pain Rating, measured over Daily from admission to discharge, up to 1 year.
| 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 is change in inpatient participant pain rating. The described measure asks participants to rate pain on a scale from 1 to 10, where 10 indicates more pain. Ratings were intended to be collected daily from admission to discharge, up to 1 year. The registry does not state a particular summary measure of change, such as a difference between defined time points or an average across observations.
Pain is a participant-reported outcome: it records the participant’s own assessment rather than an observer’s rating of a clinical sign. Repeated ratings can, in general, describe how a symptom varies over time during a hospital stay. They can also capture experiences that may not be represented by procedural or clinical outcomes. These are general features of repeated symptom measurement, not findings from this study.
The endpoint’s usefulness for estimating a treatment effect depends on having interpretable observations and a specified approach to summarizing them. Neither the pain observations nor an estimated change are presented in the registry record. The record states that the data cannot be presented because the participants could reasonably be identified. It therefore does not establish the direction, size, or precision of any change in pain. The analysis method for repeated ratings is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a completed pilot study with two enrolled participants and a single intervention group. Its primary outcome was change in inpatient pain rating, but the pain data cannot be presented because the participants could reasonably be identified. No estimate of change, uncertainty interval, or statistical test result is reported. Thus, the registry record does not permit a quantitative interpretation of the primary outcome.
The design also limits what any observed change could establish. Without a control group or random allocation, a change during the study could not be separated from other influences using a direct between-group comparison. In general, a single-group observation can describe what happened among participants receiving the intervention, but does not by itself identify what would have happened to comparable participants under another approach. This is a design consideration, not a claim about an observed change in this study.
The record lists outcomes concerning infection, observed leakages, length of stay, fistula resolution time, and complications. It does not report results for these outcomes. It also lists 17 outcome measures but provides no outcome-analysis results. The absence of reported estimates means that neither the magnitude nor the precision of these outcomes can be assessed from the registry record.
For adverse events, the record lists zero participants at risk and zero affected for serious events, zero participants at risk and zero affected for other events, and zero deaths. Because the listed at-risk counts are zero, these entries do not provide an interpretable participant denominator for evaluating safety among the enrolled participants. They should not be read as evidence that no adverse events occurred among participants.
The registry lists no analyses. It does not report a statistical plan, a method for handling repeated pain ratings, missing-data procedures, or analysis populations. The record therefore supports a description of the study’s purpose, design, and reporting constraints, but not a conclusion about the device’s effect or safety. No sample-size or power conclusion can be drawn from the information reported.
9. Statistical Methods Explained
The registry describes a single-group pilot study, not a randomized comparison. That distinction determines the kinds of statistical conclusions the design can support. In general, random allocation helps make groups comparable in expectation, while a control group provides a reference for interpreting outcomes over the same period. Without such a comparison, observed outcomes can be described in the enrolled group, but differences attributable specifically to an intervention cannot be isolated from other explanations with the same strength.
What does a single-group design estimate?
A single-group study can document how participants’ outcomes are recorded during use of an intervention. If suitable observations and a prespecified analysis are available, researchers may estimate changes over time within the group. Such an estimate remains a description of the group’s observed course; it is not equivalent to a randomized treatment contrast. Natural changes in a condition, concurrent care, measurement variation, and other influences can contribute to a within-group change. These are general methodological considerations, not reported findings about this study.
Here, the registry does not present the primary pain observations or an estimate of change. It explains that the data cannot be presented because the participants could reasonably be identified. Without the observations and a reported summary, there is no basis in the registry record for assessing the size or direction of change, or for determining how much uncertainty surrounds it.
Why do repeated pain ratings require care?
The primary outcome was to be assessed daily from admission to discharge, up to 1 year, using a scale from 1 to 10, with 10 indicating more pain. Repeated ratings from the same participant are generally related to one another; they are not independent observations simply because they were recorded on different days. A suitable analysis of repeated measurements ordinarily needs to account for that within-participant relationship. Otherwise, uncertainty can be understated or the time pattern can be represented poorly. This is a general statistical principle. The registry record does not report an analysis method for the pain ratings, or clarify how change was to be summarized.
The endpoint description also does not specify whether the primary summary would use a particular admission rating, discharge rating, change between selected ratings, or a model of the full sequence. These choices answer different questions and can produce different summaries. The intended estimand and method are not reported in the registry record, and the hidden observations cannot be reconstructed from the outcome description.
What do uncertainty and significance tests convey?
In general, a confidence interval expresses the range of values reasonably compatible with an estimate under a specified statistical model and sampling process. Its width conveys precision: a wider interval indicates greater uncertainty about the estimated quantity. A p-value, when calculated under a stated null hypothesis and model, describes how unusual data at least as incompatible with that hypothesis would be. Neither measure by itself establishes clinical importance, proves that an effect is present, or resolves limitations in study design.
No confidence interval, p-value, or primary effect estimate is reported in the registry record. With no presented observations or analysis, those measures cannot be evaluated for this study. Their absence is particularly important for a pilot study: the word “pilot” does not itself supply a reliable estimate of effect or demonstrate that a future trial would have a particular power.
How should planning calculations be understood?
Sample-size calculations are planning tools. In general, they use assumptions about a target effect, variability, significance level, allocation, and analysis method to illustrate the amount of information a future study might require. A planning value is not an observed result and is not “observed power.” The registry record gives assumptions for a planning illustration, including a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect expressed as a fraction of an observed effect. It does not report an observed effect estimate in the outcome record. Without that estimate and the calculation outputs, no numerical planning requirement can be interpreted from the registry record.
Over-dispersion is a general issue for count outcomes when variability exceeds what a simple count model expects. If present, it can make standard errors from a basic model too small and tests too optimistic; methods that allow extra variability may be more appropriate. This point is relevant generally to outcomes such as counts of leakages or complications, but the registry record does not provide count data, model details, or evidence about dispersion in this study. No model choice should be inferred from the listed outcome names alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 17 outcome measures, including the primary pain outcome and secondary outcomes concerning infection rates, observed leakages, length of stay, fistula resolution time, and complication occurrences. When a study assesses many outcomes or performs multiple tests, the chance of at least one apparently notable result can increase. General approaches to this issue include prespecifying a primary outcome, defining a testing hierarchy, or adjusting interpretation for multiple comparisons. The registry record does not report a multiplicity strategy or a statistical analysis plan.
The primary outcome is identified as change in inpatient participant pain rating. However, the record does not report how repeated ratings would be summarized, which time comparison would be primary, or what model would be used. The registry lists no analyses, and the pain observations cannot be presented because participants could reasonably be identified.
Missing-data procedures are not reported in the registry record. The record does not state whether any outcome observations were missing, why data might be missing, or how missing observations were to be handled. It also does not describe analysis populations, such as whether analyses would include all enrolled participants or a defined subset. These omissions prevent assessment of how incomplete records might affect outcome estimates.
The lack of a reported analysis plan does not establish that no plan existed; it means the plan is not reported in the registry record. No assumptions about interim analyses, multiplicity control, or analysis populations can be made from the available registry information.
11. What the Result Does, and Does Not, Mean
The record establishes that this was a completed pilot study of a participant-matched device intended to manage enteroatmospheric fistula effluent independently of negative pressure wound therapy. It also establishes that two participants were enrolled, the study used a single group, and the primary outcome was daily inpatient pain rating from admission to discharge, up to 1 year.
It does not provide the pain data or an estimate of change. The registry specifically says participant data cannot be presented because the low enrollment could allow participants to be reasonably identified. As a result, the record does not show whether pain ratings increased, decreased, or remained similar, and it does not quantify the precision of any change.
The same limitation applies to the listed secondary outcomes: their names describe what the study intended to assess, not what was observed. Results for infection rates, leakages, length of stay, fistula resolution time, and complications are not reported in the registry record. The adverse-event entries list zero participants at risk and zero affected for serious and other events, as well as zero deaths; the zero at-risk counts mean these entries cannot establish an absence of events among participants.
Because there is no control group, the study design also cannot establish how outcomes would compare with another management approach. More generally, a small pilot can inform feasibility and help shape later research, but that general role does not supply evidence of an intervention effect when outcome estimates are unavailable. The record does not demonstrate efficacy, lack of efficacy, or safety. It leaves those questions unresolved rather than answering them in either direction.
12. Why This Trial Matters Statistically
This study is statistically notable because its registry record makes an explicit tension visible: a pilot may be intended to assess a device and its practical use, while very low enrollment can make participant-level findings difficult to report without risking identification. The record states that pain data cannot be presented for that reason. This protects confidentiality but leaves the primary outcome without a reportable estimate in the registry record.
The study also illustrates the limits of interpreting outcomes from a single group. Even if a within-group change were available, the design would not provide a randomized comparator for separating the intervention’s contribution from other influences. That distinction is important when reading any observed change in a pilot setting and should not be blurred by describing a before-and-after pattern as a controlled treatment effect.
Finally, the registry lists a range of intended outcomes but no analyses. Outcome names alone do not reveal whether the data were collected, what values were observed, how repeated measures were handled, or how uncertainty was assessed. Transparent reporting of estimates, methods, and limitations is essential for judging what a small clinical study can contribute. In this record, the most defensible statistical conclusion is about the limits of available evidence, not a quantitative effect of the device.
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 enrollment of two participants is a substantial constraint on the amount of information available, and the registry says their data cannot be presented because they could reasonably be identified. This restriction means the primary outcome cannot be evaluated from the reported record. It also prevents readers from checking the distribution of ratings, individual trajectories, or the variability of pain measurements.
The single-group design has no randomized control comparison. Accordingly, the record cannot support a direct estimate of how outcomes would differ under another management approach. The study’s pilot status does not remove this limitation, and the registry does not report a statistical analysis plan that would clarify the intended handling of the repeated ratings.
Although 17 outcome measures are listed, results for the secondary outcomes are not reported in the registry record. Methods for multiplicity, missing data, and defining analysis populations are also not reported. The registry does not provide detail on eligibility criteria, baseline characteristics, or device-use and follow-up procedures beyond the stated primary outcome timeframe. These details should not be inferred from the intervention description.
The adverse-event entries list zero participants at risk, so the listed zeros cannot be interpreted as a meaningful safety rate. Taken together, the lack of reportable outcome data, the absence of a comparator, and unreported analysis methods sharply limit what can be concluded about either outcome patterns or uncertainty.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Pilot Study Evaluating the Safety and Efficacy of a Patient-Specific Enteroatmospheric Fistula Isolation and Management Device Independent of Negative Pressure Wound Therapy — NCT04978090.
- Registry record last updated 2023-10-10; status last verified 2023-09.
- Results first posted 2023-10-10.
- 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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17. Record Summary
NCT04978090 is a completed, single-group pilot study of a 3D-printed, participant-matched enteroatmospheric fistula management device intended to isolate effluent independently of negative pressure wound therapy. The registry lists two enrolled participants, allocation as NA, masking as none, and phase as NA. It identifies Andrew Bernard as sponsor.
The primary outcome was change in inpatient participant pain rating, measured daily from admission to discharge, up to 1 year, on a scale from 1 to 10, with 10 indicating more pain. The registry states that data cannot be presented because participants could reasonably be identified given the low enrollment. It lists secondary outcomes involving infection, observed leakages, length of stay, fistula resolution time, and complications, but does not report their results. The record lists 17 outcome measures and no analyses. It does not report a statistical analysis plan, missing-data methods, or multiplicity procedures.