Effect of T6 Dermatome Electrical Stimulation on Gastroduodenal Motility in Healthy Volunteers: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect of T6 Dermatome Electrical Stimulation on Gastroduodenal Motility in Healthy Volunteers (NCT03316105), a randomized na study. The primary outcome is The Effect of T6 Dermatomal Electrical Stimulation on Subjects Stomach Motor Activity.

2. Clinical Question

The clinical question concerns whether stimulation at the T6 dermatome changes stomach motor activity, and in which direction. The registry describes a randomized, parallel-group comparison of stimulation with no TENS stimulation. The posted primary outcome description does not specify a numerical measure of motility, an instrument, units, or a decision threshold. It therefore identifies the physiological question without defining how a change would be quantified or judged.

The study title specifies healthy volunteers, while the condition entry is “Weight Loss.” Those entries are not reconciled in the registry record, and further eligibility details are not reported in the registry record. The primary outcome timeframe is described as through study completion, an average of 1 year. The record also states that recruitment was stopped because of an electrical device malfunction. It does not report an analyzed estimate comparing stimulation with no stimulation, so the stated question remains unanswered by posted primary outcome results.

3. Trial Design

The registry describes a randomized, double-masked, parallel-group study. Participants were assigned to TENS stimulation or no TENS stimulation, rather than being described as receiving both conditions in sequence. The record lists an enrollment of 16. It does not specify the randomization procedure, allocation concealment, or who was masked; those details are not reported in the registry record.

The intervention is identified as the Elira Investigational TENS device. The brief summary says the research was intended to assess the effect of T6 dermatomal electrical stimulation delivered by a TENS unit on stomach motor activity. The arm descriptions say that participants in both groups were to have a narrow tube placed into the small intestine by a study physician and trained technician. They also mention use of a small amount of fluoroscopy to check tube placement. The posted arm descriptions end mid-sentence, so further procedural details are not reported in the registry record.

The phase is listed as NA, and Mayo Clinic is named as the sponsor. The study start date is 2017-09-06, and the primary completion date is 2018-06-21. The overall status is terminated. The primary outcome timeframe is “through study completion, an average of 1 year,” but the record does not explain how that average was determined or whether every participant was followed for the same duration. The primary outcome record notes an electrical device malfunction and that recruitment was stopped. The registry does not describe the malfunction, its timing, or any changes made to the study procedures.

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

Analysis population for the primary outcome, as defined in the registry: Electrical device malfunction; recruitment was stopped.

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 The Effect of T6 Dermatomal Electrical Stimulation on Subjects Stomach Motor Activity, measured over through study completion, an average of 1 year.

The primary outcome is titled “The Effect of T6 Dermatomal Electrical Stimulation on Subjects Stomach Motor Activity.” Its description says the study was testing whether dermatomal electrical stimulation would speed up or slow down stomach motor activity. Thus, the intended endpoint concerns the direction and magnitude of a change in gastric motor activity, not a clinical outcome such as symptom relief.

In general, a prespecified primary endpoint gives a trial a principal outcome around which its main comparison can be framed. A clearly defined measure can support interpretation by specifying what is measured, how it is summarized, and when it is assessed. Those details are important because “motor activity” may be represented by different measurements, and the meaning of a change depends on the measurement and its scale.

The registry record does not give a numerical endpoint definition, unit, parameter, or dispersion measure. It describes the timeframe as through study completion, an average of 1 year, but does not provide further timing details. No primary outcome analysis is reported. Consequently, the endpoint description communicates the research question, but the posted record does not show a quantified comparison or establish how precisely the intended change was estimated.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record supplies limited information about the statistical methods used for the primary outcome. It identifies randomization, double masking, and a parallel-group model, but it does not report an analysis plan, a statistical test, a model, an effect measure, or a method for handling incomplete outcome data. The following explains the general statistical ideas that would be relevant to interpreting a group comparison; it does not describe methods confirmed to have been used in this trial.

What does randomization contribute?

In general, random assignment is intended to make treatment groups comparable, on average, with respect to factors that may affect the outcome. It can reduce systematic differences that arise when people or investigators choose treatment according to participant characteristics. Randomization does not guarantee that groups are identical, especially in a small study, and it cannot remedy problems that occur after assignment, such as unmeasured outcomes or changes in how the intervention is delivered. The specific sequence-generation and allocation-concealment methods are not reported in the registry record.

What does masking mean in this record?

The study is labeled double-masked. In general, masking is intended to limit the influence of treatment knowledge on participant experience, outcome assessment, or study conduct. The label alone does not identify which people were masked or how masking was maintained. Because the comparator is no TENS stimulation, details about how the groups were kept unaware of assignment, if applicable, are especially relevant to understanding the design; those details are not reported in the registry record. It would be inappropriate to infer the masking procedure from the label alone.

How should a group comparison be interpreted?

In general, a comparative analysis estimates how the outcome differs between assigned groups. A useful report identifies the outcome scale, the group summaries, the estimated contrast, and an uncertainty interval. A confidence interval reflects the precision of an estimate under the assumptions of the analysis; a narrow interval indicates greater precision than a wide interval, but the interval cannot correct for bias or an unsuitable outcome definition. For this trial, the registry does not report a numerical motility measure, a contrast, or an interval, so these features cannot be evaluated.

The outcome description asks whether stimulation speeds up or slows down stomach motor activity. For an analysis to address that question, the direction represented by higher or lower values would need to be clear, and the measurement time and summary would need to be specified. The registry gives a general timeframe of through study completion, an average of 1 year, but does not report an operational definition of the endpoint. The analysis method, including whether it would adjust for baseline measurements or other variables, is not reported in the registry record.

What do the planning assumptions mean?

The record includes a general sample-size planning illustration based on an observed effect. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. The record distinguishes the form of a planning output: for time-to-event outcomes it would be a total number of events, and for other outcomes it would be participants per arm. These are planning assumptions, not evidence that the trial was designed using them or that a corresponding sample size was achieved.

A planning calculation asks how much information might be needed to detect a specified effect under stated assumptions. It is not an estimate of the effect actually observed, and it is not observed power. In this record, no primary outcome effect is reported, and no analysis is listed. The planning assumptions therefore cannot be used to infer the trial’s primary result or its precision. A sample-size justification for the actual study is not reported in the registry record.

Could distributional features affect analysis?

In general, the choice of model should reflect the type and distribution of the outcome. Over-dispersion occurs when count data vary more than a model assumes; if not addressed, uncertainty estimates can be too optimistic. That concept matters only if an outcome and model make it relevant. The registry record does not define the motility endpoint as a count outcome or report a model, so it does not establish whether over-dispersion or any other distributional issue arose in this study.

The record lists zero analyses for the primary outcome. It does not report interim analyses, stopping rules for statistical evidence, or multiplicity adjustments. The study’s stated recruitment stoppage is attributed to an electrical device malfunction, not to an interim statistical finding. The exact analysis population, exclusions, missing-data approach, and treatment of protocol deviations are not reported in the registry record. Without those details and an outcome analysis, statistical significance and precision cannot be assessed.

10. Multiplicity, Missing Data and Analysis Populations

The registry record identifies a primary outcome concerning stomach motor activity, but it does not provide an analysis of that outcome. It does not report statistical tests, p-values, confidence intervals, or a prespecified method for controlling multiplicity. Whether the investigators planned additional outcomes or multiple comparisons beyond the recorded outcome is not reported in the registry record.

In general, multiplicity arises when several outcomes, time points, subgroups, or statistical comparisons are examined. Considering many possible findings can increase the chance that at least one appears notable by chance. A statistical plan may address this by prioritizing a primary comparison or adjusting inference across tests. The record does not give enough information to determine whether any such plan was used. The primary outcome is described with a broad timeframe, but distinct assessment times or categories are not specified.

The primary outcome record notes an electrical device malfunction and that recruitment was stopped. It does not state how many primary outcome observations were available, whether any participants lacked endpoint data, or how incomplete observations were handled. The analysis population—such as whether all randomized participants were included in an intended-assignment analysis—is not reported in the registry record. No exclusions or reasons for exclusion from an outcome analysis are listed.

These omissions matter because missingness and analysis-population choices can affect both the estimated comparison and its uncertainty. In general, an analysis restricted to participants with recorded outcomes may differ from an analysis that accounts for all randomized participants, particularly if missingness is related to assignment or outcome. No such relationship can be assessed from the posted record. The recorded safety groups do not establish the primary-outcome analysis populations, and the safety counts should not be treated as a substitute for missing efficacy data.

11. 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.

The registry records safety information separately for TENS Unit Stimulation and No TENS Unit Stimulation. The numbers at risk are 9 for the stimulation entry and 7 for the no-stimulation entry. Both entries record 0 serious adverse events and 0 other adverse events. Each also records 0 deaths, and no serious adverse-event terms are listed.

These figures describe what is recorded in the registry for the listed groups. They do not show that adverse events are impossible, nor do they establish that the device or procedure is free from risk. The record does not report the duration of safety follow-up for each group, definitions used for adverse events, or detail about how events were collected. It also does not explain how the safety groups relate to the primary-outcome analysis populations.

With no primary outcome analysis reported, the safety counts cannot answer whether stimulation changed stomach motor activity. They should be read as recorded event counts, not as evidence about the intended motility endpoint or a complete characterization of safety.

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

The registry record establishes that a randomized, double-masked, parallel-group study was planned to examine T6 dermatomal electrical stimulation and stomach motor activity in healthy volunteers. It identifies TENS stimulation and no TENS stimulation as the comparison conditions, lists the Elira Investigational TENS device, and describes the primary question as whether stimulation would speed up or slow down motor activity. It also records enrollment of 16 and a terminated status.

What the record does not establish is the answer to that question. There is no posted primary outcome analysis, numerical estimate, uncertainty interval, or reported direction of effect. The intended endpoint is not defined with a measurement scale or units. As a result, readers cannot determine whether the groups differed, how large a difference might have been, or how precisely it was estimated. No claim that stimulation did or did not affect motility is supported by the reported primary outcome information.

The absence of an analysis should not be confused with a finding of no effect. It also should not be interpreted as evidence of benefit. A planned research question and the design intended to investigate it are not equivalent to an analyzed result. The record’s planning assumptions do not fill this gap: they describe a general sample-size illustration, not an observed treatment effect or an analysis of the enrolled participants.

The safety record reports no serious adverse events, other adverse events, or deaths in the two listed groups. Those observations are limited to the registry’s recorded safety fields and do not establish the absence of all possible harms. The record attributes stopped recruitment to an electrical device malfunction, but does not provide further detail on the malfunction or its consequences.

The appropriate interpretation is therefore descriptive and limited: the study was registered to investigate a physiological question, recruitment was stopped, and a primary outcome result is not posted. The record cannot support a quantitative conclusion about the effect, precision, or clinical significance of T6 dermatomal electrical stimulation on stomach motor activity.

13. Why This Trial Matters Statistically

This study illustrates why a clearly stated research question and an interpretable endpoint are both necessary for statistical conclusions. The registry names a directional question—whether stimulation speeds up or slows down stomach motor activity—but does not define the motility measure, its units, or the numerical comparison. Without that information, even a reported difference could be difficult to interpret in physiological terms.

It also illustrates the difference between design information and outcome evidence. Randomization, masking, and a parallel-group model describe how a study is structured. They do not themselves show whether the intervention changed the outcome. An estimate and an assessment of uncertainty are needed to understand the strength and precision of the observed comparison. In this case, no primary analysis is listed, so the design cannot be converted into a conclusion about the research question.

The recruitment stoppage is statistically relevant because incomplete enrollment or follow-up can limit the amount of outcome information available. The record says recruitment stopped because of an electrical device malfunction, but does not report the number of primary outcome observations or how any incomplete data were handled. Those details would be needed to assess the consequences for estimation and uncertainty.

Finally, the safety counts and sample-size planning assumptions answer different questions from the primary endpoint. Recorded adverse-event counts describe reported safety events, while planning assumptions concern hypothetical information requirements under stated conditions. Neither substitutes for an outcome estimate. The record is a useful reminder that transparent reporting of endpoints, analysis populations, missing data, and uncertainty is essential to interpreting a clinical trial.

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 most consequential trial-specific limitation is the absence of a reported primary outcome analysis. Although the record lists an enrollment of 16, it gives no motility estimates, group summaries, uncertainty intervals, or analysis population for that endpoint. The number enrolled cannot by itself indicate how much usable outcome information was available or how precise an estimate would have been.

The endpoint is described in directional terms but lacks a reported measurement definition, units, and assessment procedure. The timeframe is given as through study completion, an average of 1 year, without details about assessment timing or participant-level follow-up. These gaps prevent evaluation of whether the intended physiological outcome was measured consistently or how a change should be interpreted.

The record states that an electrical device malfunction led to recruitment being stopped. It does not report when the malfunction occurred, its nature, whether it affected data already collected, or whether it changed intervention delivery. The study is marked terminated, but the registry does not explain further how termination affected follow-up or data completeness. The relationship between the “Weight Loss” condition entry and the healthy-volunteer title is also not explained.

Details needed to assess potential bias are not reported in the registry record, including the randomization procedure, allocation concealment, which parties were masked, the primary statistical model, missing-data handling, and the analysis population. Safety follow-up duration and event-collection methods are also not reported. These limitations do not show that a bias or adverse outcome occurred; they identify uncertainties that cannot be resolved from the posted record.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Effect of T6 Dermatome Electrical Stimulation on Gastroduodenal Motility in Healthy Volunteers — NCT03316105.
• Registry record last updated 2019-05-30; status last verified 2019-05.
• Results first posted 2019-05-30.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry record describes a randomized, double-masked, parallel-group study sponsored by Mayo Clinic, comparing T6 dermatomal TENS stimulation with no TENS stimulation. The title identifies healthy volunteers, and the primary question concerns whether stimulation would speed up or slow down stomach motor activity. The listed device is the Elira Investigational TENS device.

Enrollment is recorded as 16. The study started on 2017-09-06, had a primary completion date of 2018-06-21, and is marked terminated. The primary outcome record states that an electrical device malfunction led to recruitment being stopped. No primary outcome analysis is reported, and the motility measure is not defined in numerical terms.

The safety entries record 0 serious adverse events, 0 other adverse events, and 0 deaths in each listed group. Those counts do not provide a result for the primary motility question. The registry record does not report an estimate of the effect, its precision, or the methods used to analyze the primary endpoint.