eCoin for OAB Feasibility Follow-on Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for eCoin for OAB Feasibility Follow-on Study (NCT03655054), a na na study. The primary outcome is Change From Baseline in Urgency Urinary Incontinence Episodes as Measured by a 3-day Voiding Diary..

2. Clinical Question

The study is framed as a prospective, multicenter follow-on evaluation of safety and effectiveness in people with UUI. Its brief summary also describes changes in overactive bladder symptoms measured by voiding diaries and patient-reported outcomes through 24 weeks of eCoin therapy, corresponding to 28 weeks from study device reimplantation. The registry record does not report numerical results for those changes.

Because all participants received the intervention and there is no concurrent comparator group, the study can describe outcomes observed during follow-up but cannot directly estimate how those outcomes would differ under a separate control condition. Changes from baseline may be informative about the course of symptoms after treatment, but a within-group change is not itself a controlled estimate of treatment effect.

3. Trial Design

The registry record describes a prospective, multicenter, single-arm follow-on study of eCoin tibial nerve stimulation. It lists enrollment of 23 and a completed status. The listed phase and allocation are NA, and masking is recorded as none. No separate control arm is described. The record identifies Valencia Technologies Corporation as the sponsor.

The brief summary says the study evaluates safety and effectiveness in subjects with urgency urinary incontinence and follows changes from baseline in overactive bladder symptoms. The primary outcome is a change in urgency urinary incontinence episodes measured by a 3-day voiding diary at 12 weeks after device activation. The summary also describes follow-up of voiding-diary symptoms and patient-reported outcomes through 24 weeks of therapy, or 28 weeks from study device reimplantation. The record does not explain the relationship between these follow-up descriptions and the reporting of individual outcomes.

The primary outcome is a continuous measure expressed as episodes per day, with the parameter specified as a mean and dispersion as a standard deviation. The record identifies secondary outcomes concerning change in urgency urinary incontinence episodes and safety, including adverse events in patients implanted 6 months after implantation. Numerical results beyond the adverse-event counts are not reported in the registry record.

A single-group design is suited to describing observations among participants who received the intervention. It does not provide a concurrent counterfactual group, so changes over time could reflect factors other than the intervention, including natural symptom variation, concurrent care, or the influence of being monitored. These are general design considerations, not reported explanations of this study's findings.

The registry record does not report a sample-size justification, a detailed statistical analysis plan, or participant flow through follow-up. It also does not describe the criteria for the analysis population or how missing observations were handled. The record's enrollment figure should therefore be read as the reported enrollment, not as evidence that every participant contributed data to every endpoint.

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 From Baseline in Urgency Urinary Incontinence Episodes as Measured by a 3-day Voiding Diary., measured over 12 weeks after device activation..

The primary endpoint is change from baseline in urgency urinary incontinence episodes, measured with a 3-day voiding diary. The unit is episodes per day, the summary parameter is the mean, and the listed assessment time is 12 weeks after device activation. The registry record does not report the numerical change, its standard deviation, or a confidence interval.

A voiding diary records events over a defined observation period. In general, diary-based measures can turn a participant's experience into a count that can be summarized and compared across assessment times. Using a daily rate expresses the recorded count relative to the diary period, but the registry record does not describe the detailed diary instructions, scoring rules, or procedures for incomplete diaries.

Change from baseline focuses on how the recorded measure differs from each participant's starting value. In general, this can account for some differences in baseline symptom frequency when summarizing follow-up. However, a within-group mean change does not by itself establish what would have happened without the intervention. Without a control group, changes may also reflect natural variation, regression to the mean, concurrent care, or other influences. These are general interpretive considerations, not reported findings in this study.

The endpoint is clinically oriented toward symptom frequency, while its statistical summary describes an average change across the analyzed observations. The registry record does not provide the distribution of individual changes, the number contributing to the analysis, or an estimate of uncertainty. Consequently, the size and precision of the observed change cannot be assessed from the endpoint information recorded.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

For a continuous endpoint such as episodes per day, a common descriptive summary is the mean and standard deviation. The mean represents the average observed value or change in the analyzed group. The standard deviation describes how spread out individual observations are around that average. These quantities answer different questions: the mean describes the central tendency, while the standard deviation describes participant-level variability. The registry record specifies these summaries for the primary endpoint but does not report their values.

Change from baseline can be calculated for each participant with data at both baseline and follow-up, then summarized across participants. In general, analysis of change uses each participant's starting value as a reference. The resulting average can be easier to interpret as a shift in symptom frequency than a follow-up value alone. However, the registry record does not describe the exact analysis method, whether all available observations were used, or how missing baseline or follow-up diaries were treated.

A confidence interval is a general statistical way to express uncertainty around an estimate. It gives a range of values compatible with the data under the method's assumptions; it is not a guarantee that the true value lies in that particular interval. A narrower interval generally indicates greater precision, while a wider interval indicates more uncertainty. No confidence interval for the primary outcome is reported in the registry record, so its precision cannot be assessed.

A hypothesis test is a general method for assessing how compatible data are with a specified null hypothesis under a statistical model. A p-value is not the probability that the null hypothesis is true, and it does not measure the size or clinical importance of an effect. The registry record lists 0 analyses and does not report a p-value or a statistical test for the primary outcome. It also does not report the prespecified testing procedure or a significance threshold for the endpoint.

The single-group structure limits the questions that statistical analysis can answer. A within-group comparison of baseline with follow-up can estimate change over time among observed participants. It cannot, by itself, distinguish an intervention-associated change from changes that would have occurred in the absence of the intervention. A randomized comparison can address that distinction more directly by comparing groups under a design intended to balance other influences, but no such comparison is described in this record. This is a general design explanation, not a claim about a specific alternative trial.

For count outcomes, such as episodes recorded in a diary, the distribution may be uneven or more variable than a simple statistical model assumes. In general, over-dispersion means the observed variability exceeds the variability expected under a model such as a basic Poisson count model. When over-dispersion is present, methods that account for it can produce more appropriate uncertainty estimates. The registry record does not state whether the diary counts were modeled as counts, analyzed as daily rates, or assessed for over-dispersion. No particular model should therefore be attributed to this trial.

Sample-size calculations are planning tools. In general, they depend on assumptions about the effect to detect, variability, allocation, significance level, and desired power. A planning calculation does not show that a study had a particular probability of detecting an effect after the results are known. The record's planning illustration is described as based on an observed effect and as assuming a hypothetical two-arm, equally allocated comparison, a two-sided significance level of 0.05, and a normal approximation. That setup is not the actual single-group design described for this study. The observed effect needed for such an illustration is not reported in the registry record, so no planning result can be interpreted from the information recorded.

Allocation, masking, and comparator structure affect what a result can support. Here, allocation is recorded as NA, masking as none, and the model as single group. In general, the absence of a masked control can leave outcomes more open to expectation and measurement influences, particularly for subjective reports. The registry record does not describe any steps intended to address those influences. This is a general methodological consideration and not evidence that bias occurred.

Outcome reporting also determines what can be evaluated. A named endpoint and measurement time identify what was intended to be assessed, but they do not reveal the observed effect, its variability, or its uncertainty. The record lists 4 outcome measures and 0 analyses. The statistical methods and numerical results for the primary endpoint are not reported in the registry record. Accordingly, the endpoint definition supports a description of the planned measurement, not a quantitative assessment of the result.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("eCoin Tibial Nerve Stimulation")
n   <- c(23)
m   <- c(-2.2)
sp  <- c(3.3)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  eCoin Tibial Nerve Stimulation  23  -2.200  3.300  -3.627  -0.773

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists 4 outcome measures, including the primary diary-based change outcome and secondary outcomes concerning urgency urinary incontinence episodes and safety. It does not report a multiplicity strategy, such as a hierarchy of tests or an adjustment for examining multiple outcomes. The record lists 0 analyses, and no inferential results are reported. Without a stated testing plan and results, it is not possible to assess how multiple comparisons were handled.

In general, examining several outcomes or time points can increase the chance of observing a seemingly notable result by chance if each is tested separately. Statistical approaches to multiplicity can control or describe that issue, but the appropriate approach depends on the prespecified questions and analysis plan. No such plan is reported in the registry record, so no method should be assumed.

Missing-data procedures and analysis populations are also not reported in the registry record. There is no description of how incomplete diaries, missed visits, withdrawal, or unavailable measurements were handled. The record does not identify whether the primary analysis included all enrolled participants, only participants with complete measurements, or another defined population. Enrollment of 23 therefore does not establish the number with evaluable primary-endpoint data.

In general, missing observations can affect both the estimate and its uncertainty, particularly if the likelihood of missingness is related to symptoms or other participant characteristics. Different methods make different assumptions about why values are missing. Because the registry record does not specify a method or describe the extent and pattern of missingness, the potential impact cannot be assessed.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

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

Most frequent non-serious adverse event terms

The safety figures list 23 participants at risk for serious adverse events, with 0 affected, and 23 at risk for other adverse events, with 6 affected. The record also lists 0 deaths. These are counts for the eCoin tibial nerve stimulation group. They do not provide event-level descriptions.

The registry record describes safety follow-up in all patients implanted 6 months after implantation. It does not provide the terms of the reported other adverse events, their severity, timing, duration, or whether investigators considered them related to the device or procedure. It also does not clarify whether the figures count participants with at least one event or give a fuller event-level accounting beyond the affected-participant counts. The serious-event terms are not reported in the registry record.

In general, an adverse-event count is descriptive. It does not, by itself, establish causation, and the absence of recorded serious events in this group does not rule out uncommon harms or events not captured in the record. Without a comparator group and fuller event descriptions, these figures cannot be used to estimate comparative safety. The counts should be read alongside the limited follow-up and reporting details recorded.

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

The registry record establishes that a prospective, multicenter, single-group follow-on study was conducted and that its primary endpoint concerned change in diary-recorded urgency urinary incontinence episodes. It also records enrollment of 23 and lists adverse-event counts. Those details describe the study's design and some safety reporting, but they do not provide the numerical result for the primary endpoint.

Because the primary outcome's mean change, standard deviation, confidence interval, and analysis results are not reported in the registry record, the size and precision of any symptom change cannot be evaluated from this record. The endpoint's definition alone does not show whether observations increased, decreased, or remained similar over follow-up. No treatment effect estimate can be extracted from the endpoint description.

Even if a within-group change were reported, a single-group study would not establish how outcomes would have differed under a separate control condition. In general, the absence of a concurrent comparator leaves possible changes from natural symptom fluctuation, concurrent care, and other influences unresolved. This does not determine what caused any observed change; it describes the limits of the design.

The safety counts indicate that 0 participants were listed as having serious adverse events, 6 were listed as having other adverse events, and 0 deaths were recorded. The nature and circumstances of the other events are not reported in the registry record. These figures cannot characterize event severity, relatedness, or comparative risk.

The record also does not report missing-data procedures, analysis populations, or a detailed statistical plan. As a result, the completeness and precision of outcome estimates cannot be assessed. The study record is informative about the questions and measurements intended, but it does not support a quantitative conclusion about the primary endpoint or a controlled causal comparison.

14. Why This Trial Matters Statistically

This study is statistically notable because its primary question is expressed as change from baseline in a repeated symptom measure. That setup focuses attention on how diary-recorded episode frequency may vary over follow-up within the observed group. It also illustrates the distinction between describing change over time and estimating a treatment effect relative to a comparator.

The single-group follow-on design can provide descriptive information about participants who received eCoin tibial nerve stimulation. It cannot, on its own, distinguish intervention-associated change from the other influences that may affect symptoms over time. This distinction is important when interpreting any uncontrolled before-and-after outcome, regardless of the direction of change.

The endpoint is defined in a way that supports a quantitative summary: a mean change in episodes per day, with standard deviation as the stated measure of dispersion. Yet the numerical endpoint result is not reported in the registry record. The contrast between a clearly named measure and absent outcome estimates shows why registration details and posted results serve different purposes. A defined endpoint tells readers what was intended to be measured; it does not tell them what the data showed or how precisely the result was estimated.

The safety record similarly distinguishes counts from fuller interpretation. It reports affected-participant counts, but not event terms or relatedness assessments. Those counts are a starting point for describing reported safety observations, not a complete account of the nature or comparative frequency of events.

For clinical researchers and statisticians, the record highlights the importance of reporting analysis populations, missing-data methods, uncertainty estimates, and the relation between planned endpoints and reported results. Without these elements, readers cannot judge the precision or robustness of an outcome estimate. These general considerations apply to interpreting this record; they do not imply that unreported analyses were or were not performed elsewhere.

15. 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 statistical interpretation is that numerical results for the primary endpoint are not reported in the registry record. The record specifies the measure, unit, summary parameter, dispersion, and assessment time, but gives no estimate of change or uncertainty. This prevents assessment of the magnitude, direction, and precision of the primary outcome.

The single-group design has no concurrent comparator. Any within-group change would therefore be descriptive rather than a controlled estimate of the difference attributable to the intervention. The registry record also lists masking as none. In general, lack of masking can influence participant-reported or diary-recorded outcomes, although the record does not establish that such influence occurred.

Enrollment is reported as 23, but participant flow and the number contributing to each outcome are not reported in the registry record. Missing-data methods, analysis populations, baseline characteristics, and details of the diary completion process are also not reported. These omissions limit assessment of representativeness, completeness, and potential bias in any outcome summary.

The registry record does not report a detailed statistical analysis plan or multiplicity procedures. It lists 4 outcome measures and 0 analyses, but does not explain the analysis approach for the primary endpoint or the handling of multiple outcomes and time points. Safety reporting is limited to counts without event terms, severity details, or relatedness assessments. The record describes follow-up through 24 weeks of therapy in the brief summary and a safety assessment 6 months after implantation, but further detail on outcome-specific follow-up completeness is not reported.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: eCoin for OAB Feasibility Follow-on Study — NCT03655054.
• Registry record last updated 2022-10-17; status last verified 2022-10.
• Results first posted 2021-04-26.
• 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.

19. Record Summary

This completed, prospective, multicenter, single-group follow-on study evaluated eCoin tibial nerve stimulation in people with urgency urinary incontinence. The registry record lists enrollment of 23, allocation as NA, and masking as none. No comparator group is described.

The primary endpoint is change from baseline in urgency urinary incontinence episodes measured by a 3-day voiding diary at 12 weeks after device activation. It is specified as a mean in episodes per day, with standard deviation as the dispersion measure. The numerical primary-endpoint result and its uncertainty are not reported in the registry record.

The safety record lists 0 serious adverse events among 23 at risk, 6 participants with other adverse events among 23 at risk, and 0 deaths. Event details are not reported in the registry record. Missing-data procedures, analysis populations, and a detailed statistical analysis plan are also not reported.