Treadmill Oscillation Walking to Improve Weight Transfer During Gait Following Stroke: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Treadmill Oscillation Walking to Improve Weight Transfer During Gait Following Stroke (NCT05541705), a na na study. The primary outcome is Peak Vertical Ground Reaction Force in the Paretic Limb During Walking.

2. Clinical Question

The clinical question is about a measured change over time within participants, rather than a difference between treatment groups. The registry describes treadmill oscillation walking as an intervention for individuals post-stroke and identifies a 6-week TOW intervention in its hypothesis statement. Its stated hypothesis anticipated increased hip abductor and knee extensor muscle activity and torque production, greater limb loading, and faster walking relative to baseline. These are hypothesized directions, not reported findings.

The primary endpoint narrows the question to paretic-limb loading during walking. Other aspects named in the study description include hip and knee neuromechanics and gait characteristics. The registry lists three outcome measures and three analyses, but details for the other measures and analyses are not reported in the registry record. The central interpretive question is therefore whether the posted primary outcome includes a quantified pre-training-to-post-training change and how precisely that change is estimated. Numerical results for that change are not reported in the registry record.

3. Trial Design

This is a completed, single-group study sponsored by the University of Texas at Austin. The registry lists an enrollment of 18 and a study status of COMPLETED. The listed study start is 2022-12-15, and the primary completion date is 2025-07-31. The intervention is Treadmill Oscillation Walking, categorized as behavioral. The record does not describe a separate control group or randomized allocation; allocation is listed as NA and the model as SINGLE GROUP.

The study description frames the intervention as a way to examine immediate and short-term effects on hip and knee neuromechanics and gait characteristics in individuals post-stroke. It refers to a 6-week TOW intervention and states a hypothesis of improvement relative to baseline. That anticipated change is not evidence of an observed effect. The record’s hypothesis statement refers to a population of N=15, whereas the listed enrollment is 18; the reason for this difference is not reported in the registry record.

Masking is listed as NONE, and phase is listed as NA. These registry entries do not establish further details about how measurements were collected, whether assessors knew the measurement occasion, or how participants entered the study. Such details are not reported in the registry record. The named primary assessment compares pre-training with a measurement taken within one week after training completion, designated week 7.

A single-group before-and-after design can describe change over time among participants who receive the intervention. Without a separate randomized control group, it cannot by itself distinguish intervention-related change from other explanations for a before-and-after difference. The record does not report a protocol, a sample-size justification for the study, or details of the statistical analysis plan. The planning assumptions associated with the sample-size illustrations are not evidence that the trial used a two-arm design; the registered study model remains single-group.

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.

Before assignment: Because only one intervention group was included in this project, participants were assigned to the same group after enrollment.

Overall Study

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 Peak Vertical Ground Reaction Force in the Paretic Limb During Walking, measured over pre-training, within one week after training completion (week 7).

The primary endpoint is peak vertical ground reaction force in the paretic limb during walking, measured in Newtons/kg. Ground reaction force describes the force exerted by the ground on the body during contact. The peak vertical component captures the highest measured vertical force during the relevant walking interval. Expressing force relative to body mass can help describe loading in a way that accounts for differences in participant size, although the registry does not report additional measurement details.

The endpoint is relevant to the study’s stated interest in limb loading during gait. The hypothesis describes increased limb loading as one anticipated change after treadmill oscillation walking. The primary outcome is specifically a force measure; it should not be treated as a direct measure of all aspects of gait function, muscle activation, torque, walking speed, or daily mobility. Those are distinct concepts, and the registry description mentions some of them as broader interests or hypothesized changes.

The registry identifies the summary measure as a mean and the dispersion measure as a standard deviation. It describes the endpoint as change from pre-training to post-training, with the post-training measurement taken within one week after training completion at week 7. The numeric mean change, its standard deviation, and any confidence interval or test result are not reported in the registry record. Consequently, the endpoint definition clarifies what was intended to be measured, but the registry record does not quantify the magnitude or precision of the change.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The design and endpoint determine what a statistical result would mean. This study is registered as a single-group investigation, and its primary endpoint compares pre-training measurement with post-training measurement within one week after training completion at week 7. It is therefore a within-group change question. It is not a randomized treatment-versus-control contrast, and statistical methods for a two-group randomized comparison should not be assumed to describe the registered design.

What does a mean change represent?

For a continuous measure, a mean summarizes the central value of observations. In this study, the registry identifies the primary endpoint as peak vertical ground reaction force in the paretic limb and specifies a mean with standard deviation. A mean change would express the average difference between the pre-training and post-training measurements under the analysis definition. The sign and magnitude would need to be interpreted using the scale and direction of the endpoint. The registry does not give a numerical mean change, so the observed direction and magnitude cannot be stated.

A standard deviation describes the spread of individual observations around a mean. It is not the same as a confidence interval and does not, on its own, show how precisely the group mean change has been estimated. Precision also depends on the amount of usable information and the analysis. The registry identifies standard deviation as the dispersion measure but does not report its value for the primary endpoint in the record described.

What would a confidence interval add?

General statistical explanation: a confidence interval gives a range of values compatible with the data and the interval’s method, under the assumptions of the analysis. A narrower interval indicates greater precision than a wider interval, but an interval does not resolve design limitations or establish causation. No confidence interval for the primary change is reported in the registry record. As a result, there is no posted interval from which to assess the precision of the estimated change.

General statistical explanation: a p-value evaluates how unusual data would be under a specified null model and its assumptions. It is not the probability that the null hypothesis is true, and it does not measure clinical importance. A p-value without an effect estimate would also leave the magnitude difficult to judge. The registry record does not report a primary p-value or enough analysis detail to identify a test and its assumptions.

Why does the single-group structure matter?

In a before-and-after design, the same group is observed at different times. Comparing each participant with their own earlier measurement can account for stable differences between people in the description of change. However, the design lacks a concurrent randomized group that could help distinguish intervention-related change from other time-related explanations. Statistical adjustment cannot create the protection against bias that random allocation and a suitable control comparison can provide. The record does not report additional design features that would alter this interpretation.

Measurements taken at two occasions can also be affected by incomplete follow-up or differences in who contributes data at each occasion. A paired analysis, for example, would ordinarily depend on usable measurements from both occasions for the relevant participants. Whether the registered analyses used paired data, another method, or a different analysis population is not reported in the registry record. The method, handling of missing observations, and assumptions about those observations therefore cannot be inferred.

How should planning illustrations be read?

The planning assumptions describe illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. Those assumptions concern planning illustrations and do not make the study a two-arm trial. The record does not report that these were the trial’s own design calculations. Sample-size illustrations estimate the participants needed under stated assumptions; they are not observed power and do not establish what the study was able to detect in practice. No specific planning values should be interpreted as results from participants.

General statistical explanation: in continuous outcomes, over-dispersion means that variability is greater than a model assumes. When variability is understated, uncertainty can also be understated, making intervals too narrow or test results misleading. Appropriate modeling depends on the outcome distribution and design. The registry does not report evidence of over-dispersion, a model choice, or diagnostic checks for this endpoint, so none should be presumed.

The registry lists three analyses, but the analytic methods, model specification, covariates, and any sensitivity analyses are not reported in the registry record. These omissions prevent a detailed appraisal of whether the analysis matched the measurement structure and how robust the result was to alternative choices. The endpoint definition and design can be described; an unreported statistical procedure cannot be reconstructed from those details.

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("Treadmill Oscillation Walking")
n   <- c(18)
m   <- c(0.01)
sp  <- c(0.06)
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  Treadmill Oscillation Walking  18  0.010  0.060  -0.020  0.040

11. Multiplicity, Missing Data and Analysis Populations

The registry identifies three outcome measures and three analyses. It does not report the full set of outcomes, distinguish which analyses were primary or secondary beyond naming the primary endpoint, or describe a strategy for controlling the risk of false-positive findings across multiple tests. Without those details, the effect of multiplicity on interpretation cannot be assessed. If several outcomes or analyses are examined, each test contributes to the overall opportunity for a chance finding; general statistical methods can address that issue, but the method used in this study is not reported in the registry record.

Missing-data methods are also not reported in the registry record. The listed enrollment is 18, but the number included in the primary analysis and the number with measurements at both time points are not stated. The record does not describe the extent or reasons for missing endpoint data, whether any observations were excluded, or how incomplete measurements were handled. It is therefore not possible to determine whether the reported analysis, if available, represents all enrolled participants or a subset.

The analysis population is not reported in the registry record. There is no basis for labeling the results as intention-to-treat, per-protocol, or another population. The distinction matters because the participants included and the rules for inclusion can affect the estimand and interpretation of a before-and-after comparison. The hypothesis statement’s N=15 and the enrollment of 18 do not establish analysis denominators; the registry does not explain their relationship.

These reporting gaps limit assessment of both the completeness and the selectivity of the analysis. They do not establish that missing data or multiplicity caused bias, but neither can those concerns be ruled out using the available record.

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.

The safety entries list 18 participants at risk for serious adverse events and 0 participants affected. For other adverse events, the record also lists 18 at risk and 0 affected. Deaths are listed as 0, and no top serious adverse event terms are listed. These are the registry’s reported counts for the Treadmill Oscillation Walking group.

Zero recorded events means that the registry lists no affected participants for these categories; it is not proof that an event is impossible or that every aspect of safety was fully captured. The record does not provide additional details about event definitions, collection procedures, duration of safety monitoring, or how events were attributed. The number at risk is not necessarily the number with complete follow-up for every safety measure, unless the record establishes that relationship.

Safety counts should also be kept separate from the primary outcome. The absence of recorded adverse events does not quantify change in peak vertical ground reaction force, and it does not establish an efficacy result. These entries describe what the registry reports for the safety categories, while the primary endpoint’s numerical results are not reported in the registry record.

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

The record establishes that a completed single-group study examined treadmill oscillation walking in individuals post-stroke. It specifies peak vertical ground reaction force in the paretic limb as the primary endpoint and describes a comparison between pre-training and within one week after training completion at week 7. This is useful information about the research question and the intended timing and meaning of the primary measure.

The record does not report the numerical primary outcome. It therefore does not show whether the mean force changed, the size or direction of any change, or the precision of an estimate. The hypothesis anticipated increased limb loading and changes in other gait-related measures, but a hypothesis is not an observed finding. Without posted outcome estimates and uncertainty measures, no conclusion about the size or statistical reliability of change can be drawn from these entries.

Even if a before-and-after change were available, the single-group structure would limit causal interpretation. A change over time among participants receiving training would not by itself show that training caused the change. A randomized comparison with a suitable control group can address some alternative explanations more directly; the registry does not describe such a comparison for this study.

The record also leaves important analytic details unreported, including the primary analysis population, missing-data handling, and multiplicity strategy. These limits do not negate the study’s descriptive value, but they constrain evaluation of its results and robustness. The enrollment of 18 and the hypothesis statement’s N=15 are both recorded, without an explanation of how they relate.

The appropriate reading is therefore narrow: the registry describes the intervention, the primary outcome, the intended assessment occasion, and the study structure, while the quantitative outcome needed to evaluate observed change is not reported in the registry record. No claim about benefit or lack of benefit follows from the absence of a posted estimate.

14. Why This Trial Matters Statistically

This study illustrates why trial design and outcome reporting must be read together. The primary endpoint is a continuous biomechanical measure, and the registry specifies both its unit and the timing of the pre-training and post-training comparison. Those details define what an estimate would represent and help keep interpretation focused on paretic-limb loading rather than broader claims about gait or function.

The single-group structure is statistically important. A within-group change can describe the participants’ measurements over time, but it is not equivalent to a randomized contrast between intervention and control groups. The design distinction matters before looking at any effect estimate: it shapes the causal question that the data can answer. Here, allocation is listed as NA, masking as NONE, and the model as SINGLE GROUP.

The record also demonstrates the difference between a stated hypothesis and a reported result. It describes anticipated increases in muscle activity, torque, limb loading, and walking speeds, but numerical primary outcome results are not reported in the registry record. Statistical interpretation depends on estimates and uncertainty, not only on the direction anticipated by investigators.

Finally, transparent reporting of analysis populations, missing data, and multiplicity supports evaluation of how results were obtained and how much confidence to place in them. Those details are not reported in the registry record. This makes the study useful for understanding a planned clinical measurement question, while limiting what can be concluded statistically from the posted entries.

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 direct limitation for statistical interpretation is that numerical results for the primary endpoint are not reported in the registry record. Without a mean change, dispersion estimate, confidence interval, or test result, the magnitude and precision of any observed change cannot be evaluated. The registry identifies three outcome measures and three analyses, but the other outcome and analysis details are not reported in the registry record.

The single-group design does not include a randomized control comparison. A before-and-after result, if available, would describe change across measurement occasions but could not alone establish that the intervention caused that change. Masking is listed as NONE, while further details about measurement procedures and assessor knowledge are not reported in the registry record.

The listed enrollment is 18, and the hypothesis statement refers to N=15. The record does not explain the relationship between these numbers or identify the number analyzed for the primary endpoint. Analysis-population definitions, follow-up completeness, missing-data methods, and reasons for any unavailable measurements are not reported in the registry record.

The statistical analysis plan, model specification, and approach to multiplicity are also not reported. These omissions make it difficult to assess whether the analysis accounted for the outcome structure, the range of outcomes examined, or incomplete data. The planning illustrations are based on stated assumptions and the observed effect; they are not the trial’s own reported design justification, and they do not supply missing outcome evidence. These limitations concern interpretation of the registry record and do not establish that any specific bias occurred.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Treadmill Oscillation Walking to Improve Weight Transfer During Gait Following Stroke — NCT05541705.
• Registry record last updated 2026-10-26; status last verified 2026-04.
• Results first posted 2026-10-26.
• 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

NCT05541705 is a completed, single-group study sponsored by the University of Texas at Austin. It evaluates Treadmill Oscillation Walking, a behavioral intervention, in individuals post-stroke. Enrollment is listed as 18; allocation is NA, masking is NONE, and phase is NA. The study start is 2022-12-15 and primary completion is 2025-07-31.

The primary endpoint is peak vertical ground reaction force in the paretic limb during walking, measured in Newtons/kg. The registry describes change from pre-training to within one week after training completion at week 7, summarized as a mean with standard deviation. The study description refers to a 6-week TOW intervention and states hypotheses about muscle activity, torque, limb loading, and walking speeds. These are hypotheses, not outcome findings.

Numerical primary outcome results and details of the analysis population, missing-data handling, and multiplicity methods are not reported in the registry record. Safety entries list 0 of 18 affected by serious adverse events, 0 of 18 affected by other adverse events, and 0 deaths.