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 Novel Pharyngeal Metrics to Predict Dysphagia Outcomes (NCT04569097), a non-randomized na study. The primary outcome is pHRM Pressure Change (Pharyngeal).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04569097 |
| Phase | NA |
| Condition | Dysphagia, Swallowing Disorders |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 227 |
| Arms in the primary outcome | n/a |
| Lead sponsor | VA Office of Research and Development |
| Results posted | Yes |
2. Clinical Question
Population
The study enrolled Veterans with dysphagia and a control group. The control group was described as having no history of dysphagia or minimal to mild dysphagia that did not require a strengthening program. The registry record lists total enrollment as 227.
Intervention
The patient group received standard-of-care lingual strengthening. The study summary describes clinically guided oropharyngeal exercises, with strengthening as the primary goal, and planned assessments at baseline, 4 weeks after treatment initiation, and 8 weeks after treatment initiation.
Comparator
Controls did not complete a treatment paradigm and underwent data collection at parallel time points. This was a nonrandomized study, and the registry record cautions that the arms are not a like-for-like control comparison. Differences between groups therefore cannot be treated as randomized treatment effects.
Primary question
The primary outcome concerns change in pharyngeal pressure measured by pharyngeal high-resolution manometry from baseline to 8 weeks. The measure of interest is integral pressure during a 10 mL swallow at the tongue base, expressed through Pharyngeal Contractile Integral and Mesopharyngeal Max Pressure. The study aimed to assess whether pressure measures changed during care and how pressure metrics related to other outcomes. Numerical outcome results are not reported in the registry record.
3. Trial Design
This completed study followed a cohort of Veterans with dysphagia during clinically guided strengthening care and collected data from a control group at parallel time points. Allocation was nonrandomized, the model was parallel, and masking was listed as single. The registry record does not identify who was masked. The study was listed as phase NA.
The patient group received lingual strengthening; controls did not undergo a strengthening treatment paradigm. Their eligibility description allowed no history of dysphagia or minimal to mild dysphagia not requiring a strengthening program. The registry record specifically cautions that this is not a like-for-like control comparison. Differences between the groups may therefore reflect differences in participant characteristics or clinical context as well as any change over time.
Assessments were planned at baseline, 4 weeks after treatment initiation, and 8 weeks after treatment initiation. The primary outcome timeframe was baseline and 8 weeks. The study summary describes manometry, videofluoroscopy, diet assessment, functional reserve tests, and patient-reported outcome measures. Secondary outcomes included EAT-10 and diet change.
Enrollment was 227. The registry record lists the study start as 2021-06-28, primary completion as 2024-09-30, and status as completed. It describes a multisite study, but the number or locations of sites are not reported in the registry record. Numerical results and the detailed 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 | Patient Group | Controls |
|---|---|---|
| STARTED | 112 | 115 |
| COMPLETED | 79 | 75 |
| NOT COMPLETED | 33 | 40 |
Reasons for not completing this period:
| Reason | Patient Group | Controls |
|---|---|---|
| Withdrawal by Subject | 33 | 40 |
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 | Patient Group | Controls | Total |
|---|---|---|---|---|
| Participants analysed | 112 | 115 | 227 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 29 | 61 | 90 |
| Age, Categorical: >=65 years | Participants | 83 | 54 | 137 |
| Sex: Female, Male: Female | Participants | 2 | 22 | 24 |
| Sex: Female, Male: Male | Participants | 110 | 93 | 203 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 1 | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 108 | 113 | 221 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 3 | 1 | 4 |
6. Primary Endpoint
The registry lists the primary outcome as pHRM Pressure Change (Pharyngeal), measured over Baseline and 8 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mmHg·s·cm |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in pharyngeal pressure measured by pharyngeal high-resolution manometry (pHRM), with baseline and 8 weeks as the stated assessment times. The outcome is continuous and is described as a mean with standard deviation. The primary measure is integral pressure during a 10 mL swallow at the tongue base, assessed as Pharyngeal Contractile Integral (PhCI) and Mesopharyngeal Max Pressure at the tongue base. The stated unit is mmHg·s·cm.
The registry description gives a PhCI range of 100 to 600 mmHg·s·cm and says that Mesopharyngeal Max Pressure is typically ~115-210 mmHg in healthy adults. It describes positive change as movement toward the normal pressure range. These reference descriptions clarify how the investigators intended to interpret the measures; they are not observed outcome results for this study.
Pressure measures are being studied as physiological indicators of swallowing function and as possible metrics for tracking outcomes. The record says the measures are generated automatically in WiscMano and Swallow gateway. It does not report the observed means, standard deviations, changes, or comparison estimates, so the direction and precision of the study’s endpoint findings cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes the clinical question and measurement plan, but it does not report numerical results for the primary endpoint. In particular, it gives no baseline or 8-week means, standard deviations, change estimates, confidence intervals, or p-values. The study status is completed, but completion alone does not establish whether pressure measures changed, how large any change was, or how precisely it was estimated.
The primary outcome is a continuous pressure measure assessed at baseline and 8 weeks. The record explains that positive change would mean movement toward the stated normal pressure range. Without the observed measurements, it is not possible to determine whether the patient group’s pressure moved in that direction, remained similar, or moved away from it. Nor can the registry record establish whether changes differed between patients and controls.
The nonrandomized design matters when interpreting comparisons. Patients received strengthening care, while controls did not complete a treatment paradigm and could include people with minimal to mild dysphagia. As the registry itself notes, the arms are not a like-for-like control comparison. A difference between groups would not, on its own, isolate the effect of treatment from baseline differences or other factors that may vary between groups. The record does not report adjusted or unadjusted estimates that would help characterize such differences.
The study aimed to examine pressure changes, relationships between pressure-based and standard measures, and prognostic algorithms for treatment success. The registry record does not report results for these aims or describe fitted prediction models, model performance, or validation. It lists six outcome measures and zero analyses. Consequently, the posted record does not support conclusions about the strength of associations, predictive accuracy, or the ability of the proposed metrics to forecast outcomes.
Precision also cannot be judged without estimates and their uncertainty. In general, a confidence interval describes a range of values compatible with the data and analysis; its width conveys how precisely an estimate has been measured. No confidence interval for the primary change is reported in the registry record. The sample-size assumptions described for planning illustrations do not substitute for an observed effect estimate or its uncertainty.
9. Statistical Methods Explained
The registry defines the primary outcome as a continuous measure summarized by a mean and standard deviation. These are descriptive statistics: the mean represents the central value on the measurement scale, while the standard deviation describes variation among observations around that mean. They do not, by themselves, show whether a change is statistically distinguishable from chance or whether it is clinically important. The observed means and standard deviations are not reported in the registry record.
What does a change score represent?
In general, a baseline-to-follow-up change score describes how a measurement differs between two assessments for a participant or group. For this study, the primary timeframe is baseline and 8 weeks, while additional assessments were planned at 4 weeks. The registry record does not specify whether the primary analysis would use individual change scores, a repeated-measures model, or another method. It also does not report how within-person correlation across assessment times would be handled.
Repeated measurements from the same participant are usually statistically related rather than independent. In general, an analysis can account for this relationship through a suitable paired or longitudinal method. Which method was used, what covariates were included, and whether the analysis adjusted for baseline values are not reported in the registry record. These details affect the interpretation of estimated change and its uncertainty.
How should uncertainty be understood?
In general, a standard error or confidence interval describes uncertainty around an estimate, while a p-value addresses compatibility between the data and a specified null hypothesis under an analysis model. Neither is a measure of clinical importance. The registry record does not report primary-outcome estimates, confidence intervals, standard errors, or p-values, and it lists zero analyses. Statistical evidence for a change therefore cannot be evaluated from the posted record.
Continuous clinical measurements can vary substantially across people. In general, the standard deviation describes that observed spread, whereas the standard error describes uncertainty in an estimated mean. These quantities answer different questions and should not be used interchangeably. No estimates for either quantity are reported for the primary endpoint in the registry record.
What does nonrandomized allocation imply?
In general, random allocation helps balance both measured and unmeasured characteristics between study groups. Here, allocation was nonrandomized. Participants with dysphagia received strengthening care, whereas controls did not follow the treatment paradigm and were defined by a different swallowing history or care need. The record cautions that the arms are not a like-for-like control comparison. Any group contrast would therefore require careful interpretation and would not automatically represent a causal treatment effect. The registry record does not report the methods, if any, used to adjust for group differences.
The parallel model means that the registry describes distinct patient and control groups rather than a crossover sequence. It does not establish that all participants completed every planned assessment. Completion by participants, analysis populations, and handling of participants with incomplete follow-up are not reported in the registry record.
What do the planning assumptions mean?
The record describes planning illustrations based on an observed effect, with 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. These are assumptions for planning illustrations, not evidence of the study’s achieved power. Sample-size calculations are planning tools and should not be interpreted as observed power after results are known. The underlying observed effect and numerical planning estimates are not reported in the registry record.
In general, over-dispersion means that observed variability exceeds what a chosen model assumes. If present, it can make standard errors too small and statistical evidence appear more precise than it is. The registry record does not report an over-dispersion assessment or describe a model for the primary outcome. This general consideration should not be read as evidence that over-dispersion occurred in this study.
Measurement is also relevant to interpretation. The registry describes two pressure metrics and names the software systems used to assess them. It does not report reliability, agreement between software systems, assessor procedures, or how values from the two systems would be reconciled. Those measurement details are not reported in the registry record and limit assessment of reproducibility from the record alone.
10. Multiplicity, Missing Data and Analysis Populations
The study lists six outcome measures, including patient-reported outcome changes for EAT-10 and diet change. It also describes several study aims: quantifying pressure change, identifying metrics that track with outcomes, and developing prognostic algorithms. Testing multiple outcomes or relationships can increase the chance of at least one apparently notable result arising by chance. In general, multiplicity can be addressed through a prespecified hierarchy, adjustment procedure, or clear distinction between confirmatory and exploratory analyses. A multiplicity strategy is not reported in the registry record.
The registry record lists zero analyses and does not provide outcome estimates or inferential results. It is therefore not possible to determine which comparisons were conducted, whether analyses were prespecified, or how any multiplicity was handled. The detailed statistical analysis plan is not reported in the registry record.
Missing-data procedures are also not reported in the registry record. The planned assessments occurred at baseline, 4 weeks after treatment initiation, and 8 weeks after treatment initiation, but the record does not state how incomplete visits, withdrawals, or missing outcome values were handled. In general, different assumptions about missingness can affect estimates, especially when missingness is related to participant status or outcome values. No such assumption can be attributed to this study based on the registry record.
The analysis populations are not reported in the registry record. It is not stated whether the analyses included all enrolled participants, only participants with complete measurements, or another defined group. Although enrollment and adverse-event denominators are listed, those figures do not establish the population used for efficacy analyses.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Patient Group | 0 | 112 | 0.0% |
| Controls | 0 | 115 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Patient Group | 0 of 112 |
| Controls | 0 of 115 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Patient Group | 0 of 112 |
| Controls | 0 of 115 |
The registry record lists safety figures separately for the Patient Group and Controls. For the Patient Group, 112 participants were at risk in the serious-event category and 0 were affected; 112 were at risk in the other-event category and 0 were affected. For Controls, 115 participants were at risk in the serious-event category and 0 were affected; 115 were at risk in the other-event category and 0 were affected. The record lists 0 deaths in each group and no serious-event terms.
These entries describe what was recorded in the registry, not proof that no event of any kind occurred. The definitions, collection procedures, observation duration for safety, and detail on non-serious events are not reported in the registry record. The figures also do not establish comparative safety: the groups were not randomized and were not a like-for-like control comparison. The numbers should therefore be read as registry-reported event counts, not as a causal estimate of treatment-related risk.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a completed, nonrandomized study was designed to assess swallowing pressure and other outcomes in Veterans with dysphagia receiving lingual strengthening, alongside a control group. It identifies pharyngeal pressure change from baseline to 8 weeks as the primary outcome and describes the intended interpretation of positive change. It does not provide numerical efficacy results.
As a result, the record cannot establish whether pressure changed, the size or direction of any change, or the precision of an estimate. It also cannot establish whether the patient group’s changes differed from those in controls. Although the study aimed to examine links between pressure metrics and other measures and to develop prognostic algorithms, results for those aims are not reported in the registry record.
The design is observational in its allocation: participants were not randomly assigned, and the control group did not receive the treatment paradigm. The registry explicitly cautions that the groups are not a like-for-like comparison. Any comparison between them would need to account for that design limitation and should not automatically be interpreted as the effect of strengthening care.
The safety entries show zero affected participants in the listed serious and other adverse-event categories for both groups, and zero deaths in each group. They do not provide a complete account of safety monitoring or establish that no events occurred outside the recorded categories.
These limits apply to what can be concluded from the registry record, not necessarily to all information generated by the study. Detailed results and analyses are not reported in the registry record. Neither a positive nor a null treatment conclusion can be drawn from the outcome descriptions alone.
13. Why This Trial Matters Statistically
This study addresses a statistical measurement problem as well as a clinical research question: whether pressure metrics from pharyngeal high-resolution manometry can track swallowing-related outcomes over time. A physiological measure can be useful only if its values and changes can be interpreted consistently and related to outcomes that matter to participants. The registry brings together pressure measures with videofluoroscopy, diet assessment, functional reserve tests, and patient-reported outcomes, making the intended scope multimodal.
The study’s longitudinal structure is relevant because measurements were planned at baseline, 4 weeks, and 8 weeks after treatment initiation. Repeated observations can describe trajectories rather than a single endpoint, but they require analysis methods that account for correlated measurements. The registry record does not report the method used or the observed trajectory, so the statistical value of the planned repeated assessments cannot be judged from the record alone.
The nonrandomized design also illustrates why comparison groups require careful definition. Controls were assessed at parallel time points but did not complete the treatment paradigm, and the registry cautions that the groups are not like-for-like. This distinction is important when considering whether an observed difference reflects treatment, group composition, or other factors.
The study’s aims include prognostic algorithms, which require more than identifying an association in the development data. In general, prediction models need evaluation of their predictive performance and validation in data not used to build them. The registry record does not report model results or validation. Its stated aims therefore represent intended research questions, not demonstrated predictive performance.
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 primary limitation for interpreting the registry record is the absence of numerical outcome results. No observed pressure means, standard deviations, changes, or estimates of uncertainty are reported. The record lists six outcome measures but zero analyses, so the clinical findings and statistical evidence cannot be assessed from this record.
The comparison is nonrandomized, and the registry warns that the patient and control groups are not a like-for-like comparison. The control description permits minimal to mild dysphagia not requiring a strengthening program, while patients were enrolled for dysphagia and received strengthening care. The record does not report group characteristics or adjustment methods that could clarify how differences between groups were addressed.
The endpoint description identifies PhCI and Mesopharyngeal Max Pressure, but the record does not report how these measurements were summarized across software systems, their reproducibility, or the handling of values outside expected ranges. It also does not provide analysis details for repeated assessments or specify how missing measurements were handled.
The record describes aims to relate pressure metrics to outcomes and develop prognostic algorithms, but it does not report the analyses, model performance, or validation. A completed status does not resolve these omissions. The adverse-event counts are limited to the categories and denominators recorded and do not provide detailed definitions or monitoring procedures.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Novel Pharyngeal Metrics to Predict Dysphagia Outcomes — NCT04569097.
- Registry record last updated 2026-05-11; status last verified 2026-04.
- Results first posted 2026-05-11.
- 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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18. Record Summary
NCT04569097, titled “Novel Pharyngeal Metrics to Predict Dysphagia Outcomes,” is listed as a completed, nonrandomized, parallel study with single masking and enrollment of 227. It followed Veterans with dysphagia receiving standard-of-care lingual strengthening and included a control group that did not complete a strengthening paradigm. Assessments were planned at baseline, 4 weeks, and 8 weeks after treatment initiation.
The primary outcome was pharyngeal pressure change measured by high-resolution manometry, with baseline and 8 weeks as the stated timeframe. Secondary outcomes included EAT-10 and diet change. The registry record lists zero analyses and does not report numerical outcome results, detailed analysis methods, or missing-data procedures. It reports zero affected participants in the listed serious and other adverse-event categories and zero deaths in both groups.