Smartphone and 3D Printing Based Home Rehabilitation System for Chronic Stroke: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Smartphone and 3D Printing Based Home Rehabilitation System for Chronic Stroke (NCT04363944), a non-randomized na study. The primary outcome is Repetitions Completed for Each Activity in the mRehab Home Program.

2. Clinical Question

The question is principally about use of the system in a home setting and the amount of activity completed, rather than a randomized estimate of benefit relative to a control treatment. The registry’s brief summary states the hypothesis that people with chronic stroke could use the portable unit at home with minimal oversight from the research team. A hypothesis is not evidence that the intended level of use was achieved. The posted record does not report the numerical repetition results or a result establishing whether the hypothesis was supported.

The registry also lists the Wolf Motor Function Test, Nine Hole Peg Test, Difficulty Rating Scale, Systems Usability Scale (SUS), and mRehab Acceptance Questionnaire as secondary outcomes. Their inclusion indicates that the study considered measures beyond activity repetitions, but their results are not reported in the registry record. The clinical question therefore needs to be read as a feasibility and measurement question, with no reported comparison that can isolate the effect of mRehab.

3. Trial Design

This is a completed, non-randomized, single-group device study of mRehab for people with chronic stroke. The registry lists enrollment as 19 and the primary outcome population as 16 participants who completed the in-home training with their paretic hand. The study dates in the record are 2018-02-21 for the start and 2019-07-29 for primary completion. The sponsor is State University of New York at Buffalo.

The intervention is described as a home program using mRehab for unilateral and bilateral activities. The arm descriptions distinguish use in which unilateral activities can be completed with the paretic arm or hand from a description in which intended unilateral activities are completed using both hands. However, the registry explicitly notes that this is not a randomized comparison and that the arms are not a like-for-like control comparison. Differences between those descriptions should not be interpreted as randomized treatment effects.

Masking is listed as none, and allocation as non-randomized. The registry lists the phase as NA. These features, together with the single-group model, mean the record does not describe a blinded randomized efficacy trial. Its stated focus is feasibility of home use and functional changes in upper limb movement during the program.

The primary outcome is the mean number of repetitions completed for each activity during the 6 week in-home program. The record also names secondary outcomes covering motor function, dexterity, difficulty, usability, and acceptance. Although the registry lists 8 outcome measures and 14 analyses, it does not report a statistical analysis plan or explain how those measures and analyses were selected, prioritized, or handled analytically. Sample-size assumptions shown with the posted results are planning illustrations rather than the trial’s own design justification; a sample-size justification is not reported in the registry record.

The registry status is COMPLETED. That status describes the study’s administrative status and does not by itself establish that every outcome was reported or that the intervention had a particular effect. In particular, the numerical result for the primary outcome is 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: 16 participants with chronic stroke that completed mRehab in-home training with their paretic hand.

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.

Population: Individuals with stroke that completed baseline analyses and completed all assessments and training unilaterally with their paretic hand/arm.

6. Primary Endpoint

The registry lists the primary outcome as Repetitions Completed for Each Activity in the mRehab Home Program, measured over 6 week in-home program.

The primary endpoint is the total number of repetitions each participant completed for each mRehab activity during the 6 week home program. The registry says that an average total number of repetitions is reported for each activity and identifies the measure as a mean of a continuous measure, with standard deviation as the dispersion measure.

Repetition counts describe engagement with the activities and the amount of practice recorded during the home program. In a feasibility study, such a measure can help characterize whether and how much activity participants completed in the intended setting. It is not, by itself, a direct measure of motor recovery, independence, or improvement relative to usual care. A higher or lower count would need contextual interpretation, including the activity involved and the participant’s opportunity and ability to complete it.

The outcome is activity-specific: the record describes an average for each activity, rather than a single pooled count across activities. No activity-level means or standard deviations are reported in the registry record. Consequently, the magnitude and variability of repetitions cannot be described from the registry information. Nor can the endpoint alone establish whether participants used mRehab with minimal oversight, since a numerical repetition summary does not directly quantify oversight or usability.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean describe?

For a continuous measure, a mean is a summary of the observed values. In this study, the registry identifies the mean number of repetitions completed for each activity as the primary outcome summary. A mean can provide a compact description of the recorded activity, but it does not show how observations are distributed around that average. The registry identifies standard deviation as the accompanying measure of dispersion. Standard deviation describes how spread out the participant-level values are around the mean; it is not the same as the uncertainty in the estimated mean.

Because the measure is activity-specific, interpretation depends on the activity being summarized. Repetition counts for different activities need not represent the same task or opportunity for practice. The record does not describe a combined endpoint or a rule for pooling activities, so a single overall repetition total should not be inferred. The actual means and standard deviations are not reported in the registry record.

What would a confidence interval add?

In general, a confidence interval expresses the statistical uncertainty around an estimated quantity under the assumptions of the analysis. It helps readers distinguish an estimate’s central value from the range of values that remain compatible with the data and method. Its width depends on the data and analysis, and it should be interpreted alongside the study design and the endpoint definition. The registry record does not report confidence intervals for the primary outcome, so its precision cannot be assessed from the registry information.

A confidence interval would not resolve design limitations. In a single-group study, an interval around a mean repetition count could describe uncertainty about that group’s mean under the analysis assumptions, but it would not create a control comparison or establish what would have happened without mRehab. Precision and causal interpretation are separate issues.

Why does the design matter for statistical interpretation?

Random allocation can support a comparison by balancing measured and unmeasured prognostic factors on average, subject to chance. This registry describes the study as non-randomized and single-group and explicitly warns that its arms are not a like-for-like control comparison. Therefore, any contrast between the arm descriptions should not be read as if participants had been randomly assigned to comparable alternatives. The registry does not report an adjusted comparison or a statistical plan that would address differences between groups.

Masking is listed as none. In general, lack of masking can matter when outcomes involve participant or assessor judgment, because expectations may influence reporting or measurement. The primary repetition endpoint is described as recorded activity, but the registry does not explain who recorded or verified repetitions or whether measurement procedures were standardized. Those details are not reported in the registry record; a particular direction or size of measurement bias cannot be assumed.

What does a planning calculation mean?

In general, a sample-size calculation describes how much information a proposed study might need to detect a specified effect under stated assumptions. The posted planning assumptions specify a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and effects defined as stated fractions of the observed effect. Such planning values are illustrations, not observed results and not observed power. They do not show the probability that the completed study detected an effect.

The assumptions are also not a description of the registered design: the registry identifies a single-group, non-randomized study and states that the arms are not a like-for-like control comparison. Therefore, hypothetical equal allocation between arms should not be mistaken for the design actually used or as evidence that the study had a particular ability to detect change. The registry does not report a sample-size justification for the trial or the numerical observed effect on which a recalculation could be based. No recalculated estimate is available in the registry record.

Why can variability matter?

In general, greater variation among participant measurements makes a group average less precise when other aspects of the data are unchanged. Repetition counts may differ across participants and activities, so reporting both a mean and a dispersion measure helps readers understand the distribution’s spread. Standard deviation summarizes variation in the observed values; it does not account for every source of uncertainty, such as missing measurements or selection into the analyzed population. Because the registry gives no activity-level values, the amount of observed variability cannot be described.

Over-dispersion is a general concern when count data vary more than a chosen statistical model expects. A model that does not accommodate such extra variation may give misleading uncertainty estimates. The registry identifies the primary measure as a continuous measure summarized by a mean and standard deviation; it does not report a count-model specification or discuss over-dispersion. It would therefore be inappropriate to claim that over-dispersion was assessed or that a particular model was used.

What can be inferred from the posted statistical detail?

The registry lists 8 outcome measures and 14 analyses, but does not report the analysis methods, inferential tests, confidence intervals, or a prespecified hierarchy of outcomes. The count of listed outcomes and analyses does not tell readers which results were primary in the analysis, whether analyses were adjusted, or how repeated measurements were handled. Those decisions are not reported in the registry record.

Statistical summaries can describe data, but their interpretation depends on the population included, the measurement process, missing observations, and the analysis plan. For this study, the record specifies the primary outcome population as participants who completed training with their paretic hand, yet it does not explain participant flow or missing data. The appropriate conclusion is therefore limited: the record defines a feasibility-oriented repetition measure, but it does not provide enough statistical results or methods detail to evaluate its estimate or precision.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 8 outcome measures and 14 analyses. It does not identify a multiplicity adjustment, a primary-secondary testing hierarchy beyond naming the primary outcome, or a procedure for controlling the chance of false-positive findings across multiple analyses. These methods are not reported in the registry record. In general, when many outcomes or analyses are examined, isolated statistically notable findings can be difficult to interpret unless the analysis plan and multiplicity approach are clear. No such inference should be made from the counts of outcomes and analyses alone.

The registry does not describe how missing outcome measurements were handled, whether analyses used all available observations, or whether any imputation method was used. It also does not provide participant flow or explain why the primary outcome population is described as 16 while enrollment is listed as 19. Reasons for non-completion or exclusion, if any, are not reported in the registry record. The two entries should therefore retain their distinct meanings rather than being combined into an assumed analysis denominator.

The record does not specify whether the analysis population was defined in advance, whether any participants were excluded from particular activity summaries, or how deviations from the home program were handled. Those details are not reported in the registry record. Without an analysis plan and outcome-level data, it is not possible to assess the sensitivity of the reported findings to missingness, participant selection, or multiple testing.

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 a group titled “Use of mRehab in a Home Program.” For that group, 19 participants are listed as at risk for serious adverse events and 0 as affected. The record also lists 19 at risk for other adverse events and 0 affected, with 0 deaths. These are the registry’s recorded counts; they should be read as event reporting for the period and definitions used in the record.

Zero recorded events does not prove that risk is absent. It also does not show that all possible adverse events were actively sought, that every participant had complete safety follow-up, or that an event could not have occurred outside the recorded definitions. The registry does not describe safety surveillance procedures, event definitions, follow-up completeness, or a detailed adverse-event analysis, so those details are not reported in the registry record.

The figures describe this study group and do not provide a comparative safety estimate. Because the study is non-randomized and single-group, the adverse-event counts cannot establish whether events were more or less frequent than under a control condition. The record lists no top serious adverse-event terms. The counts should not be interpreted as a general guarantee of safety.

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

The study is relevant as a feasibility investigation of a home rehabilitation system for people with chronic stroke. It describes a portable mRehab program involving unilateral and bilateral activities and identifies repetitions completed for each activity as the primary measure. The registry also names measures of motor function, dexterity, perceived difficulty, usability, and acceptance. These choices show the range of questions the study intended to examine, but they do not substitute for reported results.

The record does not report the activity-level repetition means or standard deviations, nor does it report the listed secondary outcome results. It therefore does not establish how much activity participants completed on average, how variable their completion was, or whether function changed. The hypothesis of successful home use with minimal oversight is stated in the summary, but the registry’s posted information does not report whether that hypothesis was supported.

The study’s non-randomized, single-group design also limits comparative interpretation. It does not provide a randomized control contrast, and the registry cautions against treating the arm descriptions as a like-for-like comparison. Even if an outcome change were reported, attributing that change specifically to mRehab would require attention to the lack of a control comparison and other possible explanations. No numerical efficacy claim can be drawn from the information reported in the registry.

The enrollment entry of 19 and the primary outcome population of 16 describe different aspects of the record. The registry does not explain the relationship between them or report participant flow. The safety entry records zero serious adverse events, zero other adverse events, and zero deaths among the stated at-risk group, but those entries do not establish that risk is absent or provide a comparative safety estimate.

In short, the record identifies a feasibility question, an activity-based primary endpoint, and a set of secondary measures. It does not provide the outcome values or analytic detail required to judge the magnitude, precision, or comparative meaning of results. The absence of those results in the registry is a reporting limitation, not evidence of either benefit or no benefit.

13. Why This Trial Matters Statistically

This trial matters statistically because it illustrates the distinction between a feasibility question and a comparative efficacy question. A count of repetitions in a home program can describe engagement with rehabilitation activities, but without a control comparison it cannot by itself estimate what would have occurred under an alternative. The registry explicitly describes a single-group, non-randomized design and cautions that its arms are not a like-for-like control comparison.

It also highlights the importance of defining the analysis population. The registry lists enrollment as 19 and describes the primary endpoint population as 16 participants who completed training with their paretic hand. Those entries cannot be treated as the same denominator, and the record does not explain the participant flow. Clear reporting of who contributed data to each activity summary would be important for interpreting a mean and its variability.

The primary measure is activity-specific, which makes reporting each activity’s estimate and dispersion important. A general summary cannot convey whether the amount of practice differed across activities or how consistent the recorded repetitions were. In the registry record, those numerical estimates are not reported, leaving the endpoint’s magnitude and precision unknown.

Finally, the posted planning assumptions illustrate why power calculations must be aligned with a proposed design and endpoint. Assumptions describing equal allocation between two arms do not describe the registry’s single-group design. Planning illustrations are not observed power, and they cannot replace reported results or a clear analysis plan. Together, these features make transparent outcome reporting, population definitions, and design-matched statistical methods central to interpreting feasibility studies.

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 registry record does not report the numerical results for the primary repetition endpoint or the named secondary outcomes. This prevents assessment of the observed activity level, variability, functional measures, usability, acceptance, and precision. The record also does not report confidence intervals, inferential tests, or an analysis plan. These omissions limit statistical interpretation independently of the study design.

The study is non-randomized and single-group, and the registry cautions that the arms are not a like-for-like control comparison. Accordingly, the design does not support a randomized estimate of an intervention effect. Masking is listed as none. The record does not explain who assessed or recorded the outcomes, whether assessment procedures were standardized, or whether measurement was checked independently.

The primary outcome population is described as 16 participants who completed mRehab in-home training with their paretic hand, while enrollment is listed as 19. The registry does not give participant flow or explain the difference. It also does not report how missing activity data were handled, whether the analyzed population was prespecified, or whether adherence and oversight were quantified.

The registry lists multiple outcomes and analyses but does not report how multiplicity was addressed or how analyses were prioritized. Its planning assumptions describe equal allocation between two arms, which does not correspond to the registered single-group model. A sample-size justification for the study is not reported in the registry record.

Finally, zero recorded adverse events should be understood as a report of observed entries, not proof that risk is absent. The record does not describe surveillance procedures or follow-up completeness. These limitations mean that conclusions should remain confined to the design and information actually reported.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Smartphone and 3D Printing Based Home Rehabilitation System for Chronic Stroke — NCT04363944.
• Registry record last updated 2024-01-23; status last verified 2024-01.
• Results first posted 2024-01-23.
• 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 describes a completed, non-randomized, single-group study of mRehab, a device-based home rehabilitation program for people with chronic stroke. Enrollment is listed as 19. The primary outcome population is described as 16 participants who completed in-home training with their paretic hand. The program lasted 6 week, and the primary endpoint was the mean number of repetitions completed for each activity, with standard deviation as the measure of dispersion.

The record lists secondary measures of motor function, dexterity, difficulty, usability, and acceptance. It records 0 serious adverse events, 0 other adverse events, and 0 deaths in the stated at-risk group. It does not report numerical primary or secondary outcome results, participant flow, missing-data handling, or a statistical analysis plan. The registry cautions that the study’s arms are not a like-for-like control comparison; the posted information therefore does not establish a comparative treatment effect.