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 Endoscopic Suturing System for Tissue Apposition (NCT00495222), a na na study. The primary outcome is Knotting Elements Placed.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00495222 |
| Phase | NA |
| Condition | Obesity |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Ethicon Endo-Surgery |
| Results posted | Yes |
2. Clinical Question
Population
People with obesity who were regaining weight after successful weight loss following gastric bypass, with a dilated gastrojejunal (GJ) anastomosis. The registry record reports enrollment of 9 participants.
Intervention
Tissue plication using the Endoscopic Suturing System (ESS), intended to bring tissue together and reduce the size of the dilated GJ anastomosis.
Comparator
No separate comparator group is described. The registry lists a single-group model and allocation as NA, so this record does not describe a like-for-like control comparison.
Primary question
How many knotting elements are placed during the plication procedure? The primary endpoint is recorded as a number of elements, with the timeframe specified as intra-operative. The registry also describes post-procedure weight follow-up to assess whether weight loss is resumed, but does not report a result for that follow-up.
3. Trial Design
This completed feasibility trial evaluated the Ethicon Endo-Surgery Endoscopic Suturing System for tissue apposition and reduction of a dilated GJ anastomosis in people regaining weight after successful weight loss following gastric bypass. The registry identifies obesity as the condition and reports enrollment of 9 participants. The sponsor is Ethicon Endo-Surgery. The study start is listed as 2007-02 and primary completion as 2008-04.
The registry lists a single-group model, allocation as NA, and masking as NONE. It therefore does not describe a randomized comparison or a control arm. The listed intervention includes tissue plication as a procedure and the Endoscopic Suturing System and Tissue Plication as devices. The arm description states that ESS is used for tissue apposition and reduction of the dilated anastomosis.
The stated feasibility objective concerns use of the suturing system and placement of knotting elements during plication. The brief summary also says post-procedure weight would be followed to assess whether weight loss is resumed. The registry lists phase as NA. Further details about eligibility criteria, procedural standardization, follow-up duration, and study conduct 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 | Tissue Plication |
|---|---|
| STARTED | 9 |
| COMPLETED | 9 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Intent to Treat
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 | Tissue Plication |
|---|---|---|
| Participants analysed | 9 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 9 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age Continuous | years | 35.5 (SD 5.5) |
| Sex: Female, Male: Female | Participants | 7 |
| Sex: Female, Male: Male | Participants | 2 |
| Region of Enrollment: United States | participants | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Knotting Elements Placed, measured over intra-operative.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | elements |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is “Knotting Elements Placed,” measured as a number of elements during the intra-operative period. The description specifies completion of plication and states that 1-3 knotting elements are placed per procedure. The endpoint population is Intent to Treat.
This count describes a procedural feature: how many knotting elements were placed while the tissue plication was completed. In general, a process measure can document whether and how a procedure was carried out. It does not, by itself, measure a later change in weight or establish how durable the tissue apposition is. The registry’s brief summary mentions post-procedure weight follow-up, but the primary endpoint listed is knotting-element placement, not weight change.
The registry record does not report the observed endpoint value, a summary across participants, or an estimate of variability. It also does not report a definition of how endpoint data were aggregated or any inferential analysis. Consequently, the recorded endpoint description clarifies what was to be counted, but does not establish what the trial observed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a small feasibility study with a single group and enrollment of 9 participants. Its primary endpoint is a count of knotting elements placed during plication. The record identifies the endpoint and its intra-operative timeframe, but does not report the observed count or any analysis. The primary result is therefore not reported in the registry record.
The endpoint is procedural rather than a comparative measure of clinical outcome. A count of elements placed can describe the conduct of the plication procedure. Without reported participant-level results or a summary statistic, the reader cannot assess the distribution of counts or the extent of variation. The record’s description of 1-3 elements per procedure is part of the endpoint definition; it is not a reported summary of the trial’s observed results.
The study has no separate control group described. Accordingly, the registry record does not support a treatment-versus-control estimate. Even if a post-procedure measure had been reported, a single-group study would not provide the same basis for separating a procedure’s effects from other changes over time as a controlled comparison. No post-procedure weight result is reported in the registry record, so the planned follow-up question about resumed weight loss cannot be assessed from this record.
The trial is marked completed, but completion status is not a report of findings. The registry lists one outcome measure and zero analyses. It provides no effect estimate, confidence interval, p-value, or account of uncertainty for the primary endpoint. Thus, the statistical precision of any observed endpoint result cannot be evaluated from the registry record.
The study’s stated feasibility purpose is relevant to interpreting its scope: the record describes evaluation of a device and procedure, not a randomized comparison. However, the registry record does not report a formal feasibility criterion or a result against such a criterion. The available information supports describing the planned procedure and endpoint, but not drawing a conclusion about effectiveness, safety, or the extent of any change in weight.
9. Statistical Methods Explained
The registry classifies the study as a single-group model and gives allocation as NA. This means the record does not describe participants being assigned to different study arms for a randomized comparison. Masking is listed as NONE. The record therefore does not describe blinded assessment or a masked treatment assignment. These design details limit the kinds of statistical comparisons that can be made from the registry entry: there is no stated concurrent control group against which to estimate a between-group difference.
What does the endpoint measure statistically?
The primary endpoint is a count: the number of knotting elements placed during the procedure. Count data represent event totals rather than measurements on a continuous scale. In general, count outcomes may be summarized by their distribution, including how often different counts occur, as well as by a mean or other suitable summary. The useful summary depends on the study question and the observed data. The registry record does not report the observed count data or specify a statistical summary for this endpoint.
In general, count outcomes can vary more than a simple statistical model assumes. Over-dispersion refers to greater variability in count data than a model’s assumptions allow. If present, it can make standard errors too small and uncertainty appear more precise than it is. Whether over-dispersion is relevant to this endpoint cannot be assessed without the observed data and a stated analysis. The registry record does not report a model or diagnostic assessment.
What can a confidence interval tell the reader?
In general, a confidence interval expresses the uncertainty around an estimated quantity under the assumptions of the method used. It can show which values are reasonably compatible with the observed data and analysis. A narrow interval indicates greater precision than a wide interval, while neither interval alone establishes whether an outcome is clinically important. No confidence interval for the primary endpoint is reported in the registry record.
A p-value, in general, describes how compatible the observed data are with a specified null hypothesis under a statistical model. It does not measure the size or importance of an effect, nor does it prove that a result is true or false. A p-value also requires a defined comparison and analysis. The registry entry reports no p-value, test, or inferential analysis for the endpoint.
What does a single group permit?
A single-group study can describe the observed experience of participants who receive the intervention. It does not provide a concurrent comparison that would account for changes that might have occurred without the intervention. For that reason, estimates from a single group are descriptive of that group and its study context; they do not by themselves isolate a causal effect. This is a general design principle, not a finding about the participants in this trial.
The stated planning illustration describes assumptions for two-arm sample-size calculations, including a two-sided significance level of 0.05, equal allocation, and a normal approximation. It also says that the target effect is a stated fraction of an observed effect. These are described as planning illustrations rather than the trial’s own design. The record does not report the observed effect value or the resulting sample-size estimates, so those assumptions do not supply an analysis of this single-group study. Such planning quantities are not observed power.
The registry lists one outcome measure and zero analyses. The statistical plan, choice of summary or model, handling of uncertainty, and any interim analyses are not reported in the registry record. Without those details and the endpoint results, no reanalysis or assessment of the precision of the trial estimate is possible.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one outcome measure and zero analyses. It does not report a prespecified statistical analysis plan, any hierarchy of outcomes, or whether multiple hypotheses or repeated assessments were considered. Multiplicity procedures and their use are therefore not reported in the registry record.
The primary endpoint population is identified as Intent to Treat. The registry does not explain how that population was defined for this single-group study, whether all enrolled participants contributed endpoint data, or how any unavailable measurements were handled. The number of participants with observed endpoint data and the extent or reasons for missingness are not reported in the registry record.
The brief summary mentions following post-procedure weight, but the entry does not report the follow-up results, timing, completeness, or analytic population for that measure. It also does not state whether missing follow-up data were imputed, excluded, or addressed in another way. Without those details, the possible influence of missing data on the intended weight assessment cannot be evaluated.
These omissions prevent assessment of whether the reported analysis, if any, followed a prespecified plan or whether missing data could affect interpretation. No analysis result is reported for the primary endpoint in the registry record.
11. What the Result Does, and Does Not, Mean
The record establishes the study’s stated purpose and design: a completed, single-group feasibility evaluation of an endoscopic suturing system for tissue apposition and reduction of a dilated GJ anastomosis. It identifies the primary endpoint as the number of knotting elements placed during plication and specifies the intra-operative timeframe. It also reports enrollment of 9 participants.
The record does not report the primary endpoint result, an analysis, or a measure of uncertainty. It therefore does not show how many knotting elements were observed across participants or how consistent the procedural counts were. Although the description says 1-3 elements are placed per procedure, that description should not be mistaken for a result summary.
The brief summary says post-procedure weight would be followed to assess whether weight loss is resumed. No such outcome result is reported in the registry record. The entry consequently does not establish whether weight changed after the procedure or whether any change was attributable to the procedure.
More generally, a single-group feasibility study can describe procedural experience, but without a concurrent control group it cannot provide a controlled estimate of comparative effect. The registry does not report a formal feasibility threshold, safety results, or an analysis of clinical outcomes. Its completed status indicates that the study is marked complete in the registry; it does not substitute for outcome results.
The appropriate reading is limited to the information recorded: a stated feasibility objective, a single-group design, and a defined procedural count endpoint. Claims about effectiveness, comparative benefit, safety, or the durability of any effect are not supported by the results reported in this entry.
12. Why This Trial Matters Statistically
This trial illustrates why a clearly named endpoint and a reported result are both necessary for statistical interpretation. The registry identifies “Knotting Elements Placed” as the primary measure and describes the setting and population for that count. But without observed values, a summary, or an analysis, the endpoint definition alone cannot convey the study’s findings or their precision.
The single-group design also makes the intended question important. A procedural count can help describe how an intervention was carried out, while a controlled comparison would address a different question about differences between intervention strategies. The registry does not describe a control group, so the entry should not be read as a comparative trial.
The record further distinguishes a feasibility objective from a clinical outcome question. The stated plan to follow post-procedure weight does not make weight change a reported result. For readers assessing evidence, keeping the procedural endpoint separate from the unreported follow-up outcome helps prevent a study objective from being confused with an observed finding.
Finally, the entry shows the value of reporting analysis details alongside study completion. The registry lists zero analyses and gives no endpoint estimate or uncertainty measure. Without these, statistical precision and the relationship between the planned question and any findings cannot be evaluated. The record is informative about the study’s scope, but its reported results are insufficient for statistical conclusions about outcomes.
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 registry record does not report the observed value for the primary endpoint, a summary of the knotting-element counts, or an uncertainty estimate. As a result, the endpoint’s distribution and precision cannot be assessed. It lists one outcome measure and zero analyses, and does not provide a statistical analysis plan or explain how endpoint data were summarized.
The study is described as single-group, with allocation listed as NA and masking as NONE. No control arm is described, so the entry cannot support a controlled comparison. The registry does not report a formal feasibility criterion against which to judge whether the study met its objective.
Although the brief summary says post-procedure weight would be followed, the registry record does not report weight outcomes, follow-up completeness, or the timing of those assessments. Safety results and other clinical outcomes are also not reported in the registry record.
Participant characteristics beyond the stated condition and study context, eligibility details, procedural variation, and handling of missing data are not reported in the registry record. The entry also does not provide enough analysis information to assess model assumptions or the statistical treatment of the count endpoint. These limits concern the information recorded and do not establish what may have been collected or analyzed outside the registry entry.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Endoscopic Suturing System for Tissue Apposition — NCT00495222.
- Registry record last updated 2009-09-10; status last verified 2009-09.
- Results first posted 2009-08-11.
- 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
NCT00495222 is a completed feasibility trial titled “Endoscopic Suturing System for Tissue Apposition,” sponsored by Ethicon Endo-Surgery. The registry lists obesity as the condition, enrollment of 9 participants, and study dates from 2007-02 to primary completion in 2008-04.
The study is described as single-group, with allocation listed as NA and masking as NONE. It evaluates tissue plication using the Endoscopic Suturing System for tissue apposition and reduction of a dilated GJ anastomosis in people regaining weight after successful weight loss following gastric bypass.
The primary endpoint is the number of knotting elements placed during the intra-operative procedure, with an Intent to Treat population. The registry lists one outcome measure and zero analyses. The endpoint result, post-procedure weight results, and analysis details are not reported in the registry record.