Lingual Endurance Exercise in Treating Post-Stroke Dysphagia: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Lingual Endurance Exercise in Treating Post-Stroke Dysphagia (NCT05523973), a na na study. The primary outcome is Adherence.

2. Clinical Question

The central statistical question is whether the training could be delivered and attempted as intended, and what changes in swallowing-related measures were observed during the study. Feasibility is addressed through adherence and dose delivery, while the broader set of measures is intended to characterize swallowing function and patient experience. Those aims are distinct: completion or adherence describes engagement with the program, whereas changes in swallowing measures describe outcomes over time. Without reported endpoint values and an appropriate comparison group, the record does not establish how much change occurred or whether any change was attributable to training.

3. Trial Design

The registry identifies NCT05523973, titled “Lingual Endurance Exercise in Treating Post-Stroke Dysphagia,” as a completed single-group study sponsored by the University of Cincinnati. Enrollment is listed as 19. The study started on 2022-08-02, and primary completion is listed as 2023-11-28. Phase and allocation are recorded as NA, and masking is listed as none. These entries describe the registered design; they do not establish that every enrolled participant completed every assessment.

Participants were to undertake lingual endurance training 2-3 times a day. The intervention description says half of participants would also complete a session of effortful swallows with the device. The record does not explain how that additional session was assigned or whether its effect was analyzed separately. Because the study is registered as single-group and allocation is NA, the study does not provide a randomized, like-for-like control comparison.

The registry summary separates feasibility from preliminary efficacy. Feasibility measures include attempted exercise and delivery of the prescribed dose. The summary also names videofluoroscopic swallowing assessment, the Modified Barium Swallowing Impairment Profile Overall Impression score, Functional Oral Intake Scale score, swallowing physiology, airway invasion, residue, and patient-reported measures. The structured primary outcome record identifies adherence, assessed at 8 weeks. The number of participants contributing to that measure is not reported in the registry record; its description specifies only participants completing baseline and final visits.

There is no detailed protocol, statistical analysis plan, or explanation of the allocation of the additional effortful-swallow session in the registry record. Those omissions limit what can be inferred about planned comparisons, analysis populations, and how the several outcomes were intended to be interpreted.

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: Only participants that completed baseline and final visits

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 Adherence, measured over Assessed at 8 weeks (study completion).

The registered primary endpoint is adherence, expressed as a percentage. Its definition is the total number of days on which exercise was attempted divided by the total number of days prescribed over 8 weeks of therapy, multiplied by 100. The measure is assessed at 8 weeks, at study completion. It is restricted to participants who completed baseline and final visits; the count included in this endpoint is not reported in the registry record.

Adherence is used as a feasibility measure: it describes whether participants attempted the prescribed exercise across the planned period. It does not by itself measure swallowing function, the quality of an exercise attempt, or whether training changed a clinical outcome. The study summary also distinguishes dose delivery, defined in terms of repetitions meeting a goal, from adherence. These concepts answer related but different questions: attempted exercise concerns participation, while repetitions meeting a goal concern how much of the intended dose was delivered.

The summary calls out additional swallowing and patient-reported measures, including MBSImP Overall Impression and FOIS. However, the structured primary endpoint’s numerical adherence result, variability, and analysis details are not reported in the registry record. Consequently, the endpoint’s observed level and precision cannot be described from the registry information.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The study is registered as single-group, with allocation listed as NA and masking listed as none. These design features matter when interpreting statistical evidence. A single-group outcome can describe what was measured in participants during the study, but it cannot provide the same controlled contrast as a comparison between intervention and control groups. In general, within-group change may reflect the intervention, the course of the underlying condition, concurrent care, measurement variation, or other influences. The registry record does not report a method for separating those influences.

What does the adherence percentage represent?

The primary measure is a percentage based on days when exercise was attempted relative to days prescribed over the 8-week therapy period. Percentages are bounded measures: they cannot extend indefinitely in either direction. In general, that bounded nature can make a percentage behave differently from an unbounded continuous outcome, particularly when observations cluster near an endpoint. The registry record does not report the distribution of adherence values or the statistical model used to analyze them, so it is not possible to determine how the observed data behaved or whether a particular modeling approach was used.

The outcome description specifies that only participants completing baseline and final visits contribute. This defines an analysis population in broad terms, but the number meeting that definition and the handling of partially completed exercise records are not reported in the registry record. In general, analyses limited to completers can differ from analyses that include all enrolled participants, especially if completion is related to adherence or outcome. Whether that issue affected this study cannot be assessed from the record.

How should averages and variability be read?

The registered outcome is continuous and is characterized in the record using a mean and standard deviation. In general, the mean describes the average value in the analyzed group, while the standard deviation describes the spread of individual values around that average. A mean alone does not show whether participants had similar experiences or whether the average conceals substantial variation. The numerical mean and standard deviation for adherence are not reported in the registry record.

A confidence interval, when reported, expresses the range of estimates reasonably compatible with the data under a statistical procedure and its assumptions. It communicates precision as well as direction and magnitude. A narrow interval generally indicates more precise estimation than a wide interval, but an interval does not resolve design limitations such as the absence of a control group. No confidence interval for the primary outcome is reported in the registry record.

What does the planning illustration mean?

The sample-size material is described as 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. It is not the trial’s own design justification, and it should not be read as observed power. A planning calculation asks what sample size might be needed under stated assumptions to detect an effect; it does not demonstrate that the study had a particular probability of detecting an effect after the fact. The numerical planning results and the effect values used for those illustrations are not reported in the registry record available for interpretation.

The planning framework refers to detecting a stated fraction of an observed effect. In general, planning around a smaller target effect requires more information than planning around a larger one, all else being equal. Such calculations depend on assumptions about the effect, variability, allocation, and analysis. They do not replace a prospective rationale or a documented design plan. The record does not report the sample-size justification used when the study was designed, nor does it report an interim-analysis plan.

Why do multiple outcomes matter?

The registry summary names several outcomes covering adherence, dose delivery, swallowing impairment, oral intake, airway invasion, residue, and patient-reported experience. In general, examining many outcomes creates a multiplicity question: the more statistical tests considered, the greater the chance that some results may appear notable by chance if each is interpreted without regard to the others. Researchers may address this through a prespecified hierarchy, adjustment, or careful emphasis on estimation rather than isolated significance tests. The registry record does not report a multiplicity strategy, a hierarchy among all outcomes, or the results needed to evaluate one.

Over-dispersion is a general concern when observed variability exceeds what a statistical model assumes. It can make standard errors too small if ignored, leading to intervals that are too narrow and tests that are too optimistic. Repeated measurements from the same participant can also be correlated, rather than behaving like independent observations. These are general considerations for repeated or clustered clinical data; the registry record does not specify the analysis model for the listed outcomes, so it is not possible to say whether or how these issues were handled.

Overall, the design information allows readers to identify the kind of study and intended measurements. It does not provide the numerical estimates, uncertainty, model specification, or analysis details needed to reconstruct statistical conclusions.

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("Lingual Endurance Training")
n   <- c(15)
m   <- c(79)
sp  <- c(29)
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  Lingual Endurance Training  15  79.000  29.000  62.940  95.060

11. Multiplicity, Missing Data and Analysis Populations

The registry summary describes a broad set of outcomes: adherence and dose delivery for feasibility, alongside swallowing impairment, oral intake, physiology, airway protection, residue, and patient-reported measures. Considering several outcomes raises a general multiplicity issue. If many statistical tests are conducted, some may appear persuasive by chance even when no meaningful effect is present. A prespecified outcome hierarchy or an adjustment procedure can help readers understand how such evidence was handled.

The registry record does not report a multiplicity adjustment, a testing hierarchy, or a statistical analysis plan explaining how the outcome family was to be interpreted. It also does not report numerical results for the primary adherence measure or the named secondary outcomes. Therefore, there is no basis in the record for determining whether any estimates were selected for emphasis, how uncertainty was handled across outcomes, or whether reported tests account for the number of outcomes examined.

Missing-data handling is also not reported in the registry record. The primary adherence description limits the population to participants who completed baseline and final visits, but does not give the number who met this condition, the reasons others may not have been included, or how incomplete exercise records were handled. In general, restricting analysis to completers can affect interpretation if completion is related to adherence or outcomes. That possibility is not evidence that such bias occurred; it identifies information needed to assess it.

The record does not specify whether analyses followed an intention-to-treat, per-protocol, or other population definition for the broader outcomes. It does not state how missing assessment values were handled or whether any sensitivity analyses were conducted. These details are not reported in the registry record, so the completeness and robustness of the outcome analyses cannot be judged.

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 serious adverse event terms

Serious events with the highest arm-level rate: hospitalization (10.5%).

The registry lists the Lingual Endurance Training group with 19 at risk for serious adverse events and 19 at risk for other adverse events. It records 2 serious adverse events, 0 other adverse events, and 0 deaths. Hospitalization is listed among the top serious event terms at 10.5%. These are the safety figures recorded for this group; the registry record does not provide a control-group safety estimate.

The at-risk figures describe the denominator recorded for the safety entries, not necessarily the number contributing to every efficacy outcome. The primary adherence measure has a separate completion-based population, whose size is not reported in the registry record. The hospitalization percentage is reported as a serious-event term; the record excerpt does not provide event-level details or clarify whether each event term corresponds to a separate participant or event. It should not be converted into a comparative risk estimate without a comparator and compatible event definitions.

Serious adverse events and other adverse events are distinct registry categories. The record does not provide detail on seriousness criteria, timing, duration, relationship to the intervention, or resolution. These figures describe what was entered in the registry, but cannot establish whether events were caused by the training. The absence of recorded deaths or other adverse events in this group should not be interpreted as proof that no risk exists.

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

The registry record describes a completed study of lingual endurance training in people with persistent dysphagia after ischemic stroke. Its stated goals include assessing feasibility and characterizing preliminary swallowing-related outcomes. It identifies an adherence measure at 8 weeks and names additional clinical and patient-reported outcomes. The record also lists enrollment as 19 and provides a small set of safety counts.

What the record does not establish is the observed adherence level, the magnitude of change in swallowing measures, or the precision of any estimates. Numerical primary and secondary outcome results are not reported in the registry record. Without those values, the results cannot be characterized as showing a particular amount of improvement, no improvement, or a consistent pattern across measures.

The design also limits causal interpretation. A single-group study does not show what would have happened to a comparable group without the training or under another intervention. Even if changes were reported, within-group change alone would not determine how much was caused by the training. The registry record does not report a controlled comparison, a causal analysis, or a statistical plan that could resolve this limitation.

Adherence is a feasibility measure, not a direct measure of swallowing function. The summary distinguishes attempted exercise from repetitions meeting a goal, and the wider outcome set addresses swallowing physiology, intake, airway invasion, residue, and quality of life. These outcomes are related to the study’s aims but represent different constructs. One cannot be substituted for another.

The appropriate interpretation is therefore bounded: the record documents a single-group study and its intended assessments, but does not contain the outcome estimates required to judge the observed results. Neither study completion nor the presence of planned outcomes supplies evidence about their numerical findings.

14. Why This Trial Matters Statistically

This study is statistically interesting because its aims combine feasibility with preliminary assessment of swallowing outcomes. Those are complementary but different questions. Feasibility measures can show whether participants attempted prescribed activity and whether the intended dose was delivered. Clinical and patient-reported measures address swallowing function and experience. Keeping these domains separate helps avoid treating participation in an intervention as evidence of an outcome change.

The adherence definition is particularly relevant: it is based on attempted exercise days relative to days prescribed over 8 weeks, while the study summary separately describes a dose-delivery measure based on repetitions meeting a goal. The distinction makes clear that following a schedule and completing the intended exercise dose are not identical. Clear operational definitions are essential for interpreting feasibility findings and comparing them with other studies.

The design also illustrates why a completed single-group study can contribute descriptive information without establishing a comparative effect. A control group can help distinguish changes associated with an intervention from changes that might occur over time or with other care. In its absence, observed changes, if reported, would need cautious interpretation. Here, the registry record does not report the outcome estimates needed even for that descriptive account.

Finally, the outcome set spans measured swallowing performance and patient-reported experience. Different measures may capture different aspects of a condition and need not move together. Reporting estimates and uncertainty for each, together with the analysis population and missing-data approach, would be important for evaluating their meaning. The registry entry makes the intended scope visible, while leaving those result details unreported.

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 most immediate limitation for interpretation is that the registry record does not report numerical results for adherence or the other named outcomes. It therefore provides no endpoint estimate, measure of variability, confidence interval, or statistical test with which to assess the observed findings. The stated enrollment of 19 does not reveal how many participants contributed to each measure or completed the required visits.

The registered design is single-group, with allocation listed as NA and no masking. There is no like-for-like control comparison in the registry record. This limits causal interpretation even if within-group changes were available. The intervention description also notes that half of participants would complete a session of effortful swallows with the device, but does not explain assignment or separate analysis of this activity.

The primary adherence population is defined as participants completing baseline and final visits, but the analysis count, missing-data procedures, and reasons for noncompletion are not reported in the registry record. The record also does not report the statistical analysis plan, approach to multiplicity across outcomes, or whether analyses accounted for repeated measurements or other features of the data. These omissions make it difficult to assess precision and robustness.

The safety information is limited to group-level counts and a listed hospitalization term. Event timing, details, relationship to training, and definitions are not reported in the registry record. The listed safety counts therefore do not establish causation or permit comparison with another group.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Lingual Endurance Exercise in Treating Post-Stroke Dysphagia — NCT05523973.
• Registry record last updated 2025-05-07; status last verified 2025-04.
• Results first posted 2025-05-07.
• 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

NCT05523973 is a completed, single-group study sponsored by the University of Cincinnati, titled “Lingual Endurance Exercise in Treating Post-Stroke Dysphagia.” The registry lists enrollment as 19, phase and allocation as NA, and masking as none. The study began on 2022-08-02, with primary completion on 2023-11-28.

The intervention is lingual endurance training, prescribed 2-3 times a day; the record says half of participants would also complete effortful swallows with the device. The structured primary outcome is adherence at 8 weeks, defined using attempted exercise days relative to prescribed days among participants completing baseline and final visits. The summary also identifies swallowing-function and patient-reported outcomes.

Numerical efficacy results and the primary adherence estimate are not reported in the registry record. Safety entries list 2 serious adverse events, 0 other adverse events, and 0 deaths among 19 at risk; hospitalization is listed at 10.5% among top serious terms. The record does not provide a controlled comparison or enough statistical detail to assess outcome estimates.