Exercise-primed Upper Extremity Motor Practice in Chronic Stroke: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Exercise-primed Upper Extremity Motor Practice in Chronic Stroke (NCT04259424), a na na study. The primary outcome is Change in Upper Extremity Impairment as Assessed by the Fugl-Meyer Assessment - Upper Extremity.

2. Clinical Question

The study’s stated aims also include examining the magnitude of the intervention’s effect on upper-extremity function and the relationship between nervous-system biomarkers and response. These aims are framed as feasibility and pilot questions. In a single-group study, observed pre-to-post change describes what happened among participants receiving the combined program; it does not by itself isolate the contribution of aerobic exercise, motor practice, or their sequence.

The registry lists the Wolf Motor Function Test and Stroke Impact Scale as secondary outcomes, covering upper-extremity function and physical function or health-related quality of life. The primary outcome’s numeric results, including the observed change and its variability, are not reported in the registry record. Consequently, the magnitude and precision of any measured change cannot be assessed from this record.

3. Trial Design

This is a completed, single-group feasibility and pilot study, not a randomized comparison. The registry records enrollment of 10 and lists allocation as not applicable. It identifies one intervention: aerobic exercise paired with upper-extremity rehabilitation. No like-for-like control arm is described, so the study design does not provide a concurrent estimate of what would have happened without the combined program.

Participants were to receive 18 intervention sessions. Each session consisted of 15 minutes of aerobic exercise on a stationary cycle followed by 200 repetitions of an upper-extremity rehabilitation program. The intervention listing names Aerobic Exercise + Duck Duck Punch, and the study summary describes Duck Duck Punch as a virtual reality-based rehabilitation game. The record’s description indicates exercise was performed before the motor practice.

The registry gives a study start date of 2021-03-22 and a primary completion date of 2022-03-29, with status listed as completed. The primary outcome was assessed before and after the intervention, approximately 6 weeks. The record does not report how many participants completed the full intervention, the number of sessions actually attended, or whether the planned repetitions were achieved.

The primary measure is change in upper-extremity impairment on the Fugl-Meyer Assessment—Upper Extremity. Secondary measures include change in upper-extremity function assessed by the Wolf Motor Function Test and change in physical function and health-related quality of life assessed by the Stroke Impact Scale. The registry lists five outcome measures and one analysis, but does not report a detailed statistical analysis plan or explain how those measures map to analyses.

Because there is no separate control group, the design is suited to describing implementation and within-group observations, not to establishing that the intervention caused any change. The registry does not report the eligibility criteria in the information available in the record, or the basis for the enrollment target.

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

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 Change in Upper Extremity Impairment as Assessed by the Fugl-Meyer Assessment - Upper Extremity, measured over Pre and post intervention, approximately 6 weeks.

The primary endpoint is change in upper-extremity impairment, measured with the Fugl-Meyer Assessment—Upper Extremity (FMA-UE). The registry describes the measure as a 33-item assessment, with the three items testing reflex response omitted because they do not measure the voluntary movement construct of interest. Each administered item is scored on a three-point rating scale, and item ratings are summed and reported out of 60 points. Higher scores indicate greater upper-extremity motor ability.

Assessments were planned before and after the intervention, approximately 6 weeks. A change score compares a participant’s measurement at the two time points. In general, a measure of impairment can help characterize the level of motor ability and whether it changed during the study period. The FMA-UE is the primary endpoint because the stated study aim concerns change in upper-extremity impairment after pairing aerobic exercise with motor practice.

The registry does not report the observed pre-intervention or post-intervention scores, the mean change, or its standard deviation. It therefore does not establish the direction, size, or precision of the primary endpoint result. Nor does the record specify whether any additional scoring or analysis choices were used beyond the measure description.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The methods help distinguish what a study was designed to describe from what its results can establish. This record describes a single-group intervention with measurements before and after treatment. It lists no randomized allocation and no separate control group. The primary outcome is continuous: it is a numerical score on the FMA-UE, reported as a mean with standard deviation in the registry’s outcome description.

What a pre-to-post change represents

In general, a change score is calculated by comparing a participant’s measurement at follow-up with that participant’s earlier measurement. A group mean change summarizes those individual changes. The standard deviation describes how spread out the observed values are around the mean; it is not itself a measure of how precisely the mean has been estimated. Precision is commonly conveyed with a confidence interval, which gives a range of values compatible with the data and the method’s assumptions.

The registry identifies change from before to after the intervention as the primary outcome, with assessment approximately 6 weeks apart. However, it does not report the group’s mean change, standard deviation, or confidence interval. Those statistics cannot be inferred from the intervention description or enrollment count. The record also does not report a statistical test result for the primary endpoint.

What a single-group design can say

In general, a single-group pre-to-post comparison describes change over time among participants who received the intervention. Without a concurrent comparison group, it cannot distinguish intervention-related change from other influences, such as natural fluctuation, changes in other care, or measurement variation. This design limitation applies even if a pre-to-post difference is statistically distinguishable from zero. A statistical test of change would not itself establish that the intervention caused the change.

The intervention includes both aerobic exercise and upper-extremity motor practice. Because the record describes one combined program and no component comparison, the effects of exercise and practice cannot be separated. The same limitation applies to the proposed priming sequence: the record does not describe a group receiving the same components in a different order or without exercise.

Mean and standard deviation

In general, the mean is a measure of the center of a set of numerical observations. The standard deviation describes variability among those observations. For a continuous outcome such as the FMA-UE, reporting both can help readers understand the group’s average result and how much participants’ values differ. Neither statistic is reported for the primary outcome in the registry record. As a result, the endpoint’s observed level and variation cannot be assessed from the posted entry.

A confidence interval is different from a standard deviation. In general, it communicates uncertainty around an estimated quantity, such as a mean change. A wider interval indicates less precision, while a narrower interval indicates greater precision under the chosen method. No confidence interval for the primary outcome is reported in the registry record, so the precision of the effect estimate is unknown.

Planning illustrations and power

The registry’s sample-size assumptions describe 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. The stated effect to detect is a fraction of the observed effect. This is a hypothetical planning exercise, not a description of this single-group study’s design: the study record lists no two-arm allocation. Any participant counts generated for that illustration are planning quantities, not observed trial results or observed power. The record does not report the trial’s own sample-size justification or the assumptions used to set its enrollment.

In general, power is a design-stage probability of detecting a specified effect under stated assumptions. It is not a measure of whether a finding is true, and it should not be calculated after a study as a substitute for interpreting the estimate and its uncertainty. A planning illustration based on an observed effect cannot establish that a small pilot was adequately powered for its aims.

Over-dispersion and outcome distributions

Over-dispersion is a general concern for count outcomes when observed variation is larger than a statistical model expects. It can make standard errors and test results unreliable if the model does not account for the extra variation. The primary outcome in this record is continuous, not a count, so count over-dispersion is not the central issue for interpreting the FMA-UE. The registry does not describe the distribution of scores or any model used to analyze them.

For continuous outcomes, general analytic considerations include the scale’s properties, the distribution of the observed changes, and whether the method appropriately accounts for repeated measurements within participants. The registry entry does not report enough analysis detail to determine which methods were used, whether assumptions were evaluated, or how missing measurements were handled.

Statistical significance and practical meaning

In general, a p-value evaluates how compatible data are with a specified statistical model and null hypothesis. It does not measure the size or practical importance of an effect. A confidence interval and the observed effect estimate are needed to assess the range of effects compatible with the data. Neither the p-value nor those effect estimates are reported for the primary outcome in the registry record. No claim about statistical significance can therefore be made from the posted information.

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("Aerobic Exercise + Upper Extremity Rehabilitation")
n   <- c(10)
m   <- c(2.6)
sp  <- c(5.2)
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  Aerobic Exercise + Upper Extremity Rehabilitation  10  2.600  5.200  -1.120  6.320

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary FMA-UE outcome and secondary outcomes involving the Wolf Motor Function Test and Stroke Impact Scale. It also lists five outcome measures and one analysis. The record does not explain how the outcome measures relate to the listed analysis, which outcomes were included in that analysis, or whether additional analyses were conducted.

When a study examines multiple outcomes or makes multiple statistical comparisons, the chance of at least one apparently notable result can increase. General methods for handling this issue include specifying a primary analysis in advance or adjusting for multiple testing. The registry record does not report a multiplicity strategy or say whether any adjustment was used. No claim about the consequences of multiplicity can be made without the analysis details.

The record does not describe how missing observations were handled, whether all enrolled participants contributed to each outcome, or whether analyses used an intention-to-treat or other defined population. It also does not report the number of participants with outcome measurements at each time point. These details matter because missing follow-up data can affect both the estimated change and the group represented by the analysis.

The enrollment count is 10, but the number who completed the intervention and the number included in each outcome analysis are not reported in the registry record. The entry also does not report whether the analysis included all participants with available data or used another rule. Readers therefore cannot assess attrition, the analysis population, or the potential effect of missing data on the reported results.

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 non-serious adverse event terms

The registry records zero serious adverse events among 10 participants at risk in the Aerobic Exercise + Upper Extremity Rehabilitation group. It records one other adverse event among 10 participants at risk and zero deaths. These are counts as entered in the registry, not estimates of comparative risk: no control group is listed.

The record does not identify the non-serious event in the posted adverse-event summary. It also does not report whether the event was considered related to the intervention, when it occurred, or whether participants were monitored for a defined period. The serious-event terms list is empty, but that does not provide a detailed narrative of safety monitoring.

In general, a small participant group and limited event counts provide little information about uncommon events. The absence of recorded serious adverse events in this group should be interpreted as the registry’s reported count, not as evidence that serious events cannot occur. Likewise, the single other event cannot establish whether the combined program increased or decreased event risk. The record’s adverse-event figures alone do not fully characterize tolerability or safety.

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

The record identifies a completed feasibility and pilot study of aerobic exercise paired with upper-extremity motor practice in chronic stroke survivors. It describes the intervention schedule, primary and secondary measures, and the intended focus on feasibility, tolerability, functional change, and nervous-system biomarkers. Those details clarify the study question and the kind of evidence it was intended to generate.

However, the primary outcome results are not reported in the registry record. There is no reported FMA-UE mean change, standard deviation, confidence interval, or test result. Secondary outcome values and biomarker findings are also not reported. The registry entry therefore does not permit a quantitative assessment of outcome change, its precision, or the relationship between biomarkers and response.

The single-group design also limits causal interpretation. A pre-to-post change, if reported, would describe participants’ change during the intervention period, but would not by itself show that the combined program caused it. There is no separate control group to provide a concurrent reference, and no comparison that isolates aerobic exercise from motor practice.

The intervention’s planned session structure should not be mistaken for evidence of adherence or completion. The record does not report attendance, actual repetitions completed, or whether the intervention was delivered as planned to each participant. Feasibility and tolerability are stated aims, but detailed feasibility results are not reported.

Accordingly, the registry record supports a description of the study design and planned measures, not a conclusion about whether the intervention changed upper-extremity impairment or function. It also cannot establish comparative effectiveness, mechanism, or the frequency of uncommon harms. Those questions require results and, for causal comparisons, a design with an appropriate comparison condition.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of the distinction between a pilot study’s aims and the conclusions its design can support. The registry describes feasibility and tolerability as central goals, alongside estimating the magnitude of change and exploring possible biomarker relationships. These questions can motivate later research, but they require clear reporting of implementation, outcomes, and uncertainty.

The study combines aerobic exercise with upper-extremity practice in a defined sequence. That makes the intervention clinically and analytically a package: a single-group result cannot attribute any observed change to one component, nor establish that exercise served as a primer. Component-specific questions would require a comparison capable of separating those effects.

The enrollment of 10 highlights why estimates from a pilot need to be interpreted with attention to uncertainty. In general, small studies can provide useful information about procedures and generate preliminary estimates, while having limited precision for outcome effects and limited ability to characterize less common events. The registry does not report an outcome estimate or uncertainty interval, so even a preliminary effect size cannot be evaluated from this entry.

Another important statistical issue is alignment between a study’s aims and its reporting. Feasibility claims are best understood with information such as participation, completion, attendance, and delivery of the planned sessions. Those data are not reported in the registry record. Similarly, outcome interpretation requires the observed scores, analysis population, handling of missing data, and statistical methods, none of which are described in enough detail to assess.

The record therefore illustrates how a completed study entry can document a protocol and intervention while leaving the central result questions unanswered. Clear reporting of estimates, precision, and analysis decisions is necessary for readers to judge what a pilot contributes and what questions remain for a controlled study.

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 main limitation for interpreting this registry entry is that it does not report the numeric results for the primary or secondary outcomes. Without observed scores, changes, measures of variability, or confidence intervals, the outcome findings and their precision are not assessable.

The study is single group, with no separate comparator. As a result, any pre-to-post change cannot be distinguished from other changes over time. The combined intervention also prevents separate estimation of the effects of aerobic exercise and motor practice. The record does not describe a design that can test whether the sequence itself contributes to an outcome.

The registry lists enrollment of 10 but does not report how many participants completed the intervention, contributed data at each assessment, or were included in each analysis. Attendance, adherence to the planned 18 sessions, and completion of the 200 repetitions per session are not reported. This limits assessment of both feasibility and the amount of intervention actually received.

Analysis details are also limited. The statistical methods, analysis population, handling of missing data, and any approach to multiple outcomes are not reported in the registry record. The sample-size justification for the trial is not reported. The planning illustration described in the registry uses a hypothetical two-arm framework and should not be read as the design or power of this single-group study.

The adverse-event entry records no serious events, one other event, and no deaths, but does not identify the other event or provide information on relatedness or monitoring duration. Thus, safety and tolerability cannot be fully characterized from these counts alone.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Exercise-primed Upper Extremity Motor Practice in Chronic Stroke — NCT04259424.
• Registry record last updated 2023-05-06; status last verified 2023-04.
• Results first posted 2023-05-06.
• 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

NCT04259424 is a completed, single-group feasibility and pilot study titled “Exercise-primed Upper Extremity Motor Practice in Chronic Stroke.” The registry lists Medical University of South Carolina as sponsor, enrollment of 10, and study dates from 2021-03-22 to primary completion on 2022-03-29.

The intervention paired 15 minutes of stationary cycling with 200 repetitions of upper-extremity rehabilitation per session, for a planned total of 18 sessions. The primary outcome was change in FMA-UE score before and after the intervention, approximately 6 weeks. Secondary outcomes were the Wolf Motor Function Test and Stroke Impact Scale.

The registry does not report numeric primary or secondary outcome results, detailed analysis methods, missing-data handling, or intervention completion and adherence. It records zero serious adverse events among 10 participants at risk, one other adverse event among 10 at risk, and zero deaths. No separate control group is described.