Fall-recovery Training for Those With Chronic Stroke and Low Falls Self-efficacy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Fall-recovery Training for Those With Chronic Stroke and Low Falls Self-efficacy (NCT04112173), a na na study. The primary outcome is Adverse Events Ending Participation.

2. Clinical Question

The study summary also proposed gathering evidence about implementation, adaptation, and limited efficacy in relation to falls self-efficacy and walking activity. Those aims describe the intended scope; they are not evidence that training was delivered or that changes in those outcomes were observed. The registry lists the Stepping Threshold Assessment of Reactive Balance as a secondary outcome, but does not report a result for it. Thus, the record frames a feasibility question but does not provide outcome findings with which to answer it.

3. Trial Design

This was a single-group study with no masking. Allocation is listed as NA, and the registry identifies no like-for-like control comparison. The intervention is described as perturbation-based fall-recovery training, with an arm description of perturbation-based balance training. The record lists the phase as NA. These labels characterize the registered design; they do not establish how much training the participant received or what activities took place.

The study was sponsored by the University of Delaware. The recorded start date was 2020-02-21, and the primary completion date was 2020-03-13. Its status is TERMINATED. Enrollment is recorded as 1. The brief summary says that 5 participants would undergo an adapted training program, but the enrollment figure is 1; the registry does not explain the difference or report the reason for termination. The actual number who began or completed training is not reported in the registry record.

The primary outcome was the number of participants who ended participation due to adverse events, assessed over 6 months. The registry explains that the study was terminated before reaching the prespecified time frame for recording this outcome, and that it was not recorded. The record lists 5 outcome measures and 0 analyses. It names the Stepping Threshold Assessment of Reactive Balance as a secondary outcome, but does not provide outcome results for that measure or the other listed measures.

Because this was a single-group study, any observed change would not by itself separate intervention effects from changes over time, measurement variability, or other influences. In this record, however, no efficacy results are available to interpret. The design and enrollment information therefore give context for the feasibility aim, but do not supply a basis for comparative or causal conclusions.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The study was terminated prior to reaching the pre-specified time frame for recording this data. This outcome measure was not recorded.

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 Adverse Events Ending Participation, measured over 6 months.

The registered primary endpoint was the number of participants who ended participation due to adverse events. Its timeframe was 6 months. This endpoint focuses on a particular aspect of tolerability: whether an adverse event led a participant to stop taking part. It does not count every possible aspect of feasibility, such as whether the training could be delivered as planned or whether participants found it acceptable. Those broader implementation details are not reported as results in the registry record.

In general, tracking discontinuation due to adverse events can help describe whether safety concerns interrupted participation. It is distinct from simply counting adverse events: an event may occur without ending participation, and the endpoint specifically concerns events that led to withdrawal. The registry gives no recorded result for this endpoint. It states that the study ended before the prespecified 6 months timeframe was reached and that the outcome was not recorded.

The separate adverse-event figures list 0 serious adverse events and 0 other adverse events among 1 participant at risk. Those figures are not a recorded value for the primary endpoint. They do not establish how many participants would have ended participation due to adverse events over the intended timeframe, and they should not be substituted for the missing primary outcome. The registry does not report why this endpoint was selected or provide an additional endpoint-specific analysis.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group study and reports 0 analyses. It does not identify a statistical analysis plan, an inferential method used for efficacy outcomes, or an estimate with a confidence interval. The methods below explain general statistical ideas relevant to interpreting feasibility and outcome studies; they should not be taken as methods documented for this trial.

What does a single-group design tell us?

In general, a single-group study can describe what happened among participants who took part. It can be useful for documenting whether an intervention was delivered, how participants engaged with it, and what measurements were collected. Without a concurrent comparator, however, a change from baseline cannot be uniquely attributed to the intervention. Changes over time, measurement variation, and other influences can also contribute. The registry lists no comparator and no reported efficacy analyses, so it offers no comparative effect estimate.

What would an effect estimate and confidence interval add?

In general, an effect estimate expresses the observed difference or change for a chosen outcome, while a confidence interval describes uncertainty around that estimate under the analysis assumptions. A wider interval indicates less precision; a narrow interval indicates greater precision. A confidence interval is not a guarantee that the true effect lies within its limits. In this record, no efficacy effect estimate or confidence interval is reported, so neither effect magnitude nor statistical precision can be evaluated from the registry results.

How should the planning illustrations be read?

The sample-size planning assumptions describe two-sided significance level 0.05, equal allocation between two arms, and a normal approximation. They also describe an effect to detect as a stated fraction of the observed effect. These are assumptions for illustrative planning calculations; they are not a description of the registered single-group design and do not establish that a comparison was conducted. Any resulting sample-size figure is a planning illustration, not observed power.

In general, a sample-size calculation asks how many observations a hypothetical design would need to detect a specified effect under stated assumptions. It does not show that a study had that number of participants, that the assumed effect was observed, or that the study achieved a particular probability of detecting an effect. The registry record does not report an efficacy estimate that would allow a reader to evaluate the effect basis for the illustrations. The figures should therefore not be used as evidence about what this trial found.

The planning description distinguishes time-to-event calculations from other outcome calculations: time-to-event illustrations use total events under the Schoenfeld approach, while other illustrations give participants per arm. That convention applies to the planning material, not to the reported enrollment of this single-group trial. A hypothetical two-arm calculation does not turn this record into a two-arm comparison.

Why can over-dispersion matter?

In general, over-dispersion occurs when observed variability in a count outcome exceeds what a statistical model assumes. If a model understates variability, uncertainty can be understated and inferential conclusions may be too optimistic. Appropriate methods may account for extra variability when the outcome and data structure call for it. The registry does not report a count outcome analysis, an over-dispersion assessment, or a statistical model for this trial, so no such method can be attributed to the analysis.

What can the adverse-event counts establish?

In general, counts describe observed events in the group and observation period represented by the data. Their interpretation depends on how many people were observed and for how long, as well as on how events were defined and collected. Counts alone do not establish that the underlying event risk is zero. The registry lists 1 participant at risk and zero recorded serious events, other events, and deaths. It does not report the observation duration associated with these safety figures or an inferential safety analysis. Those counts are therefore descriptive and limited.

The primary endpoint is not interchangeable with the safety counts. It concerns participants ending participation due to adverse events over a specified timeframe; the registry says that it was not recorded. The separate safety group counts do not provide the missing endpoint value, and no statistical adjustment can recover a measure that was not collected.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 5 outcome measures and 0 analyses. It identifies a primary endpoint and names the Stepping Threshold Assessment of Reactive Balance as a secondary outcome, but does not report results for the listed outcomes. The complete outcome hierarchy and the full list of planned statistical comparisons are not reported in the registry record.

In general, multiplicity arises when a study makes several statistical comparisons or tests several outcomes. With more tests, the chance of at least one apparently unusual result can increase unless the analysis plan addresses that issue. Possible approaches include prespecifying a primary outcome, adjusting inference across tests, or treating secondary analyses as exploratory. The registry record does not state whether any multiplicity strategy was planned or used. With no analyses reported, there are no posted inferential results for which to assess multiplicity adjustment.

The primary outcome was not recorded because the study was terminated before reaching the prespecified 6 months timeframe. The record does not explain whether other outcomes were collected, whether any measurements are incomplete, or how missing measurements were handled. Results for falls self-efficacy and walking activity are not reported. These absences should not be interpreted as evidence of no change; they mean that the registry record does not provide results to evaluate.

The analysis populations are not reported. In particular, the record does not specify who was included in any efficacy analysis or whether analyses were planned for participants who began or completed training. Enrollment is recorded as 1, but the record does not establish intervention receipt or completion. No imputation method, missing-data assumption, or sensitivity analysis is reported. Without those details and without outcome results, the effects of incomplete follow-up or missing measurements cannot be assessed.

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 lists an intervention group with 1 participant at risk. It records 0 serious adverse events, 0 other adverse events, and 0 deaths. These are counts in the registry safety record; they are not estimates of event risk with reported uncertainty. No serious adverse-event terms are listed.

These figures should be read in the context of enrollment and study duration. Enrollment was 1, and the study status is TERMINATED. The registry does not specify the observation duration represented by the safety counts. Separately, it states that the primary endpoint, which was intended to capture participants ending participation because of adverse events over 6 months, was not recorded because the study ended before that timeframe was reached.

In general, observing no events in a small group does not establish that the underlying event rate is zero. The counts are compatible only with what was observed and recorded in this study; they do not establish what would occur in a larger group or over a different observation period. The record also does not state whether the safety figures capture all events or only events meeting particular reporting criteria beyond the serious and other categories shown. They should be treated as limited descriptive counts, not as definitive evidence about safety.

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

The registry record establishes that a single-group study of perturbation-based fall-recovery training was registered for people with chronic stroke and low falls self-efficacy. Its stated purpose was to examine feasibility and gather evidence about implementation, adaptation, and limited efficacy. The recorded enrollment was 1, and the study status is TERMINATED.

It does not establish whether the training was delivered or completed, how it was adapted, or whether falls self-efficacy, walking activity, or reactive balance changed. No efficacy analyses are reported. The primary outcome—participants ending participation due to adverse events over 6 months—was not recorded because the study ended before reaching its prespecified timeframe. Therefore, there is no primary endpoint result to interpret.

The adverse-event record reports 0 serious adverse events, 0 other adverse events, and 0 deaths among 1 participant at risk. Those counts describe the registry record but do not demonstrate that the intervention has no safety risks. The record does not state the duration of observation for these counts, and the study enrolled only 1 participant.

The design also does not include a comparator group. It cannot establish a comparative effect, and the registry contains no reported efficacy estimate that could support a conclusion about benefit or lack of benefit. The study’s stated aims should not be mistaken for findings: planned assessments and proposed implementation work are not results. In statistical terms, this record is informative about the study’s design, status, enrollment, and limits on available outcome information. It does not answer whether training changes the outcomes of interest or whether it is feasible across a broader group.

13. Why This Trial Matters Statistically

Feasibility studies can address questions that arise before a larger efficacy evaluation, such as whether an intervention can be implemented and whether its procedures can be adapted for the intended population. The registry summary identifies fall recovery as a proposed rehabilitation target for people with chronic stroke and low falls self-efficacy. It also links that rationale to falls risk and limited walking activity. These are the study’s motivations, not demonstrated effects.

The record matters statistically because it distinguishes a study aim from an analyzable result. Enrollment was 1, the study was terminated, and the primary endpoint was not recorded. The registry lists 0 analyses. Those details sharply limit what can be estimated: there is no reported endpoint value, efficacy effect, or uncertainty interval. A small enrollment is not evidence of no effect; it is a constraint on the amount of information available, especially when outcomes are not reported.

The contrast between the planned 5 participants in the summary and the recorded enrollment of 1 is also relevant to interpretation, although the reason for the difference is not reported. The registry does not explain the termination or describe intervention receipt and completion. Those details would help distinguish challenges in recruitment, delivery, follow-up, and outcome collection, but they cannot be inferred from the record.

Finally, planning calculations and trial findings answer different questions. A hypothetical sample-size illustration cannot replace observed outcomes or create a comparison that the design did not include. Keeping those concepts separate prevents planning assumptions from being mistaken for evidence of efficacy or observed statistical power.

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.

Several limitations specific to this study constrain interpretation. The registry records enrollment of 1, whereas the brief summary describes a plan for 5 participants. It does not explain the gap, so the reason should not be inferred. The recorded status is TERMINATED, but the reason for termination is not reported in the registry record.

The primary endpoint was not recorded because the study ended before reaching its prespecified 6 months timeframe. This means the intended measure of participation ending due to adverse events is unavailable. The registry does not report whether any other outcomes were collected, nor does it give results for the listed secondary outcome or the proposed measures of falls self-efficacy and walking activity.

The record does not provide participant characteristics beyond the study’s intended population, and it does not confirm whether the enrolled participant started or completed training. It also does not describe the adaptations implemented, the intervention dose, or the duration of training. These omissions limit assessment of whether the intervention was implemented as intended.

The single-group design has no comparator, and no efficacy analyses are reported. Even a measured change would therefore require cautious interpretation as a descriptive observation rather than a comparative treatment effect. The record does not report a statistical analysis plan, analysis populations, missing-data methods, or multiplicity procedures. The safety counts are limited to 1 participant at risk, with no observation duration reported for those counts. Together, these features leave little basis for estimating feasibility, efficacy, or safety beyond describing the recorded status and counts.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Fall-recovery Training for Those With Chronic Stroke and Low Falls Self-efficacy — NCT04112173.
• Registry record last updated 2023-09-25; status last verified 2023-09.
• Results first posted 2022-12-01.
• 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 single-group study sponsored by the University of Delaware, with no masking and allocation listed as NA. It evaluated perturbation-based fall-recovery training for people with chronic stroke and low falls self-efficacy. The summary proposed 5 participants; recorded enrollment was 1.

The study started on 2020-02-21, had a primary completion date of 2020-03-13, and is listed as TERMINATED. The primary outcome was the number of participants ending participation due to adverse events over 6 months. It was not recorded because the study ended before the prespecified timeframe. The registry lists 5 outcome measures and 0 analyses.

The adverse-event figures list 1 participant at risk, 0 serious adverse events, 0 other adverse events, and 0 deaths. No efficacy results or comparator-group findings are reported. The reason for termination and the enrolled participant’s intervention receipt or completion are not reported in the registry record.