The Comparison of Virtual and Real Boxing Training in Hemiparetic Stroke Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Comparison of Virtual and Real Boxing Training in Hemiparetic Stroke Patients (NCT03651479), a randomized na study. The primary outcome is Wolf Motor Function Test.

2. Clinical Question

The clinical contrast is between two forms of boxing training added to neurodevelopmental training, not between boxing training and no additional training. The registry describes a randomized controlled study and identifies a real boxing group and a virtual boxing group. It does not describe a group receiving neurodevelopmental training alone, so the stated comparison cannot by itself separate the contribution of boxing training from the shared program.

The study aim also refers to cognitive status, upper extremity function, balance, and activities of daily living. The listed secondary outcomes include manual dexterity, punching analysis, balance, cognitive assessment, and activities of daily living. These outcomes capture distinct areas of performance and should not be treated as interchangeable measures of one underlying effect. The registry record does not report participant-level findings for them.

The central statistical question is whether the recorded outcome distributions differ between the randomized groups at the stated assessment time, and how precisely any difference is estimated. Without group summaries, an estimated contrast, or an uncertainty interval, the direction and magnitude of the primary comparison cannot be described from the registry record.

3. Trial Design

The registry identifies this study as randomized, with a parallel-group model and no masking. The two named groups are the Real Boxing Group and the Virtual Boxing Group. Each group received its respective boxing training in addition to neurodevelopmental training. The record gives an enrollment of 40 and lists the study status as completed. It does not report the randomization sequence method, allocation concealment, or the procedures used to assign participants.

The study start date is 2018-11-10, and the primary completion date is 2019-06-12. The phase is listed as NA. Eastern Mediterranean University is named as the sponsor. These registry entries describe the study structure and administrative record; they do not establish how treatment was delivered in practice or whether every randomized participant completed the assessments.

The primary outcome is the Wolf Motor Function Test, recorded as a mean with standard deviation on a score scale at 8 weeks. The registry describes the test as assessing upper extremity motor ability through timed and functional tasks. The listed secondary outcomes cover manual dexterity, punching performance, balance, cognition, and activities of daily living. The record lists six outcome measures and one analysis, but does not explain how outcomes were selected for that analysis or how they were analyzed.

No blinding is recorded. In an exercise-based comparison involving real and virtual boxing, participants and trainers may know which type of training is being delivered; the record does not describe masking of outcome assessors. That distinction matters because assessor knowledge could influence assessments that involve timed or functionally scored tasks. Whether this occurred cannot be determined from the registry record.

Although the registry states an enrollment of 40, it does not report the number randomized to each group in the primary-outcome analysis, the number assessed at 8 weeks, or whether participants were analyzed in their assigned groups. Those details are needed to judge the completeness and comparability of the outcome data. They 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

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 Wolf Motor Function Test, measured over 8 weeks.

The primary endpoint is the Wolf Motor Function Test (WMFT), described as a measure of upper extremity motor ability. It uses timed and functional tasks. The registry description says the commonly used version has 17 items: items 7 and 14 relate to strength, while the other 15 concern functional ability during tasks. The Functional Ability score is the sum of those 15 functional items, each scored on a 6-point ordinal scale from 0 to 5; the stated total ranges from 0 to 75. The registry says lower scores indicate lower functional levels.

This measure is relevant to the stated comparison because the training programs involve upper extremity activity, and the study aim includes upper extremity function. A structured task-based measure provides a defined outcome for comparing participants’ motor performance rather than relying only on a broad clinical impression. The timed and functional components also reflect different aspects of task performance, although the registry does not explain how those components were combined or which score was used for the primary analysis.

The endpoint timeframe is 8 weeks. The registry records the outcome as a mean and standard deviation, but does not report the group means, standard deviations, change scores, or a between-group estimate. It also does not specify whether the primary comparison was based on endpoint scores, change from baseline, or another approach. Consequently, the measure and its intended timing are identifiable, but the numerical result and its precision are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Interpreting a randomized trial requires separating the design, the outcome definition, the estimate, and the uncertainty around that estimate. The record describes randomized allocation and a parallel comparison, but does not provide the numerical primary-outcome results or enough analysis detail to reconstruct the comparison. The explanations below are general statistical context, not additional findings from the trial.

What does a mean and standard deviation describe?

For a continuous outcome, the mean describes the center of the observed scores in a group. The standard deviation describes how spread out individual scores are around that group mean. They answer different questions: a group can have a particular average while participants vary widely or narrowly around it. Reporting both helps readers understand the observed score distribution, but neither statistic alone estimates the comparative effect between randomized groups.

A between-group estimate would express the contrast in outcome between the real boxing and virtual boxing groups, using a specified analysis. Its interpretation depends on the score definition and the direction of the scale. Here, lower WMFT scores indicate lower functional levels. The registry does not report group summaries or an estimated contrast, so no numerical direction or magnitude can be described.

Why is an uncertainty interval useful?

General statistical explanation: a confidence interval presents a range of values that are reasonably compatible with the data under the method used to calculate it. It communicates precision as well as direction and scale. A narrow interval generally indicates a more precise estimate than a broad interval, while an interval spanning values on either side of no difference may leave multiple interpretations plausible. A confidence interval is not a guarantee that the true effect lies within the displayed range.

The registry does not report a confidence interval for the primary outcome. It also does not report a p-value. A p-value, when reported, measures how unusual the data would be under a specified null model and analysis assumptions; it does not measure the probability that the null hypothesis is true, the size of an effect, or its clinical importance. Without an estimate and uncertainty information, readers cannot assess how precisely the groups were compared.

What does randomization contribute?

General statistical explanation: randomization is intended to make group assignment independent of participants’ measured and unmeasured characteristics, on average across repeated assignments. It reduces the risk that treatment selection systematically determines who enters each group. In a particular trial, chance imbalances can still occur, especially when the study is modest in size. The registry gives the randomized design and enrollment, but does not describe baseline characteristics, the assignment method, or whether the outcome analysis preserved the randomized comparison.

Allocation concealment and outcome-assessor masking address different sources of bias. Concealment concerns whether upcoming assignments could be anticipated before enrollment or assignment. Masking of assessors concerns whether knowledge of group assignment could affect outcome measurement. The record states that masking was none, but does not specify which roles were unmasked or describe concealment procedures.

Why can over-dispersion matter?

General statistical explanation: over-dispersion arises when the variability in data is greater than a statistical model assumes. If a model understates variability, standard errors may be too small and uncertainty intervals too narrow. This issue is especially relevant to outcomes whose values are counts or event rates, but the appropriate model depends on the outcome’s scale and distribution. The registry describes the primary endpoint as a continuous score summarized with a mean and standard deviation. It does not report model diagnostics or an analysis method, so there is no basis to state whether over-dispersion was assessed or relevant to the primary analysis.

What can be said about planning illustrations?

General statistical explanation: sample-size planning asks how many participants may be needed under chosen assumptions about the effect to detect, variability, significance level, allocation, and analysis method. Such calculations are conditional on those assumptions. If they use an effect observed in a study, they are illustrations of planning under that assumed effect, not evidence that the study had a particular chance of finding a result. The registry describes assumptions involving a two-sided significance level of 0.05, equal allocation, and a normal approximation. It does not report the numerical planning outputs or the observed effect used for them. The trial’s own sample-size justification is not reported in the registry record.

These concepts cannot substitute for the missing outcome results. The registry permits identification of the primary measure and broad design, but does not give the quantities needed to evaluate the estimated treatment contrast, its precision, or the analysis assumptions used.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists six outcome measures, including the primary Wolf Motor Function Test and secondary measures spanning dexterity, punching, balance, cognition, and daily activities. Considering several outcomes can raise a multiplicity issue: when many hypotheses are tested, the chance of at least one apparently unusual result can increase. General statistical approaches include prespecifying a primary comparison, adjusting for multiple tests, or treating secondary analyses as exploratory. The registry record does not report a multiplicity strategy, a hierarchy among secondary outcomes, or which outcomes were included in the one analysis it lists.

The registry notes that the primary outcome has several categories or time points and was not reduced to one comparison. It does not identify the specific categories or time points represented, or explain how they were handled in the analysis. Without a clear prespecified comparison and analysis method, it is not possible to determine how the primary outcome was summarized or how any multiplicity was addressed.

Missing-data handling is not reported in the registry record. The record does not state how many participants completed the 8-week assessment, why any outcome data might be missing, whether imputation was used, or whether sensitivity analyses were performed. The analysis population is also not reported: it is unknown whether the analysis included all randomized participants, only those with measured outcomes, or another group.

These omissions matter because missing outcomes can affect both the estimate and its uncertainty, particularly if missingness differs by group or is related to participant outcomes. The registry record does not provide enough information to assess that possibility or to determine whether the analysis followed the randomized assignment.

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 records zero serious adverse events and zero other adverse events in the Real Boxing Group, with 20 at risk in each event category. It records zero serious adverse events and zero other adverse events in the Virtual Boxing Group, also with 20 at risk in each event category. Deaths are recorded as zero in both groups. These figures describe what is entered in the registry; they do not establish that no event occurred outside the recorded collection process.

A zero count can arise when no events are observed, but interpretation also depends on follow-up duration, the way events were defined, how actively they were sought, and whether participants remained under observation. The registry record does not describe those procedures or provide event-level details. It also does not give a safety analysis plan or explain whether the at-risk counts reflect all randomized participants throughout follow-up.

Serious and other adverse events are separate categories and should not be conflated. The registry supplies no terms for serious events, consistent with the recorded zero serious-event counts. These counts should be read as descriptive registry entries, not as a comparison establishing that the interventions have equal safety or that risk is absent. The record does not provide enough information to estimate comparative safety precisely.

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

The record establishes that a randomized, parallel-group study compared real boxing training with virtual boxing training, with neurodevelopmental training in both groups. It identifies hemiparetic stroke patients as the population and the Wolf Motor Function Test at 8 weeks as the primary outcome. It also describes several secondary outcome domains and records adverse-event counts for both groups.

Those details define what the investigators intended to compare, but they do not reveal the result of the comparison. No primary-outcome group means, standard deviations, estimated difference, confidence interval, or p-value are reported in the registry record. Accordingly, the available record does not show whether one group had higher or lower scores, how large any difference was, or how uncertain that difference might be.

The absence of a reported comparison is not evidence of no difference. It is also not evidence that the groups differed. Both claims would require outcome data and an analysis. Likewise, zero recorded adverse events does not prove that either intervention has no risk, and it does not establish equivalent safety. The event counts need to be interpreted alongside information about collection, follow-up, and completeness, which is not reported in the registry record.

The study’s stated aim includes function, balance, cognition, and activities of daily living, but the registry’s outcome list and study aim do not provide evidence that any of these domains improved or differed between groups. A measure’s relevance to a clinical question should not be confused with a finding on that measure. No clinical-importance threshold is reported for the WMFT, so the record also does not establish what magnitude of score difference would matter to patients or clinicians.

The appropriate conclusion is therefore limited: the registry describes the design and intended outcomes, while the numerical efficacy results and key analysis details are not reported. Readers should not infer treatment benefit, lack of benefit, or equivalence from this record alone.

13. Why This Trial Matters Statistically

This trial is statistically informative as a case study in the distinction between a registered question and a reported result. The design identifies a randomized comparison between two active training approaches, and the primary outcome is a defined functional measure at a specified assessment time. Those features make the intended contrast understandable. However, without the outcome estimate and uncertainty, the central statistical evidence cannot be evaluated.

The comparison also illustrates why intervention context matters. Both groups receive neurodevelopmental training, so the contrast concerns the type of boxing training added to that program. It does not directly estimate the effect of boxing training compared with no boxing training or with neurodevelopmental training alone. Precise wording about the comparator prevents attributing a result to a broader question than the design addresses.

The registry’s multiple outcome domains raise the importance of transparent analysis planning. Measures of dexterity, punching, balance, cognition, and daily activity can tell different stories. Prespecification and clear reporting of primary and secondary analyses help readers distinguish the main confirmatory question from additional exploratory questions. The registry record does not report how multiplicity was handled or how the listed analyses were selected.

The record also demonstrates that a stated sample-size planning framework is not enough to judge a study’s evidential strength. Planning depends on numerical assumptions and a defined outcome analysis; the relevant calculation outputs and effect assumptions are not reported. Even when such illustrations are available, they do not replace estimates from the observed data or show that an effect was detected.

For clinical researchers and biostatisticians, the main statistical lesson is to look for a clearly specified contrast, a result with an uncertainty measure, transparent missing-data handling, and a description of the analysis population. The registry provides useful design and endpoint definitions, but not the information needed to assess the primary comparative result.

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 main limitation for interpreting this study is that the registry record does not report numerical results for the primary outcome. Without group summaries or an estimated contrast and its uncertainty, the magnitude, direction, and precision of the comparison cannot be assessed. Results for the listed secondary outcomes are also not reported.

The registry’s note that the primary outcome has several categories or time points and was not reduced to one comparison leaves the primary analysis unclear. It does not specify which categories or time points were used, how they were combined or compared, or whether the analysis followed a prespecified plan. The listed mean and standard deviation format does not resolve those questions.

The record gives no baseline characteristics, eligibility criteria, treatment dose, session schedule, or details on adherence. It does not state whether the neurodevelopmental training was standardized across groups. These gaps limit assessment of how participants and interventions were represented and whether delivery was comparable, but they do not establish that a problem occurred.

Masking is recorded as none, while the roles of participants, trainers, and assessors are not described. The randomization procedure and allocation concealment are also not reported. The record does not provide follow-up completion, missing-data methods, the analysis population, or sensitivity analyses. These details are relevant to judging potential bias and the robustness of any estimate.

Finally, the registry provides adverse-event counts without describing ascertainment or follow-up duration. The counts therefore cannot establish comparative safety. The study’s own sample-size justification is not reported in the registry record, and the numerical outputs for planning illustrations are also not available in the record. These limitations restrict what can be concluded from registry information; they do not prove that the original study lacked additional data or analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: The Comparison of Virtual and Real Boxing Training in Hemiparetic Stroke Patients — NCT03651479.
• Registry record last updated 2021-11-30; status last verified 2021-11.
• Results first posted 2020-01-18.
• 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

NCT03651479 is a completed randomized, parallel-group study sponsored by Eastern Mediterranean University. It compares real boxing training with virtual boxing training using Kinect Xbox Boxing, with both groups receiving neurodevelopmental training. The population is described as hemiparetic stroke patients, and enrollment is listed as 40. Masking is recorded as none, and the phase is listed as NA.

The primary outcome is the Wolf Motor Function Test, recorded as a mean with standard deviation at 8 weeks. Secondary outcomes cover manual dexterity, punching analysis, balance, cognition, and activities of daily living. The record does not report a numerical primary-outcome comparison, secondary-outcome results, or detailed analysis methods. It records zero serious adverse events, zero other adverse events, and zero deaths in both groups. Missing-data procedures, analysis populations, multiplicity handling, and the trial’s sample-size justification are not reported in the registry record.