Forearm Rotation Orthosis for Stroke: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Forearm Rotation Orthosis for Stroke (NCT01987414), a randomized na study. The primary outcome is Canadian Occupational Performance Measure (COPM) - Performance.

2. Clinical Question

The study's stated purpose was to examine the orthosis together with task-oriented occupational therapy for functional performance in people with a hemiparetic arm. Its hypotheses also concerned active forearm range of motion, motor function of the upper extremity, and improvement among participants receiving the occupational therapy approach. The primary endpoint, however, is the COPM Performance score. It reflects participants' self-perception of their ability to perform selected tasks, rather than a direct measurement of movement or strength.

The registry describes randomized allocation and a parallel design. It does not report the details of sequence generation, allocation concealment, or the identity of any masked personnel. It also does not report a primary outcome estimate, a between-group contrast, or uncertainty around such a contrast. Consequently, the stated clinical question can be described, but the record does not establish whether the groups differed or how precisely any difference was estimated.

3. Trial Design

The registry record describes a randomized, single-masked, parallel study, with an enrollment of 18 and a status of completed. The study concerns stroke and a hemiparetic arm. The listed sponsor is the University of Minnesota. The recorded start is 2015-08, and primary completion is recorded as 2018-06. The record lists the phase as NA.

Group A's listed sequence was a forearm rotation orthosis for 6 weeks, then the orthosis plus an occupational therapy task-oriented approach for 6 weeks. Group B's listed sequence was no treatment for 6 weeks, then the occupational therapy task-oriented approach for 6 weeks. These descriptions identify the assigned conditions, but the registry record does not explain additional treatment restrictions, adherence expectations, or whether other care was permitted.

The primary endpoint was the COPM Performance score, assessed at Week 1, 8, and 15. The record describes comparisons of change between Week 1 and Week 8, Week 1 and Week 15, and Week 8 and Week 15, within and between groups. That creates several time contrasts relevant to interpretation. It does not identify a single reported numerical contrast as the result of the trial.

The registry lists 21 outcome measures and 0 analyses. Its secondary outcome descriptions include goniometric measurements of shoulder flexion, shoulder abduction, elbow extension, forearm pronation, forearm supination, and wrist extension, as well as upper-extremity strength measures for shoulder flexion and shoulder abduction. The record does not provide statistical results for these measures. It also does not report who was masked, how randomization was implemented, the planned analysis model, or a sample-size justification. Those details should not be inferred from the design labels or the intervention descriptions.

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 Canadian Occupational Performance Measure (COPM) - Performance, measured over Week 1, 8, and 15.

The primary endpoint is the Canadian Occupational Performance Measure (COPM) - Performance. It is described as a score on a scale, summarized by a mean and standard deviation. In a structured interview, each participant selects 5 tasks and rates how well they feel able to complete each task. The task ratings use a scale from 1, meaning unable to perform, to 10, meaning able to perform extremely well. The record says the total score is the mean of the individual task scores and gives its stated range as 1 to 5, from unable to perform tasks to able to perform tasks extremely well.

This measure is used to capture self-perceived functional performance. That focus is relevant to a study asking whether an orthosis and a task-oriented occupational therapy approach relate to participants' perceived ability to carry out chosen activities. It is not interchangeable with goniometric range-of-motion measures or upper-extremity strength measures, which address different aspects of function.

Assessments are listed at Week 1, 8, and 15. The registry describes examining changes within and between groups across Week 1 to Week 8, Week 1 to Week 15, and Week 8 to Week 15. It does not report the COPM scores at those assessments, the changes, or a statistical comparison. The record therefore describes what the endpoint was intended to measure, but it does not show the observed outcome or its precision.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The design labels describe how the study was organized, not what its results were. Randomized allocation means the study assigned participants to groups through a random process, according to the registry. In general, random assignment is used to reduce systematic differences between groups at the point of assignment. It does not guarantee that all characteristics will be balanced, especially in a small study, and it cannot compensate for missing outcome data or unclear analysis methods. The record does not describe the random sequence, concealment of allocation, or checks on baseline comparability.

What does a parallel design mean?

In a parallel design, participants are assigned to a group and follow that group's assigned treatment sequence. The two listed groups have different first-period conditions, then both receive the task-oriented occupational therapy approach in the later period, with Group A also receiving the orthosis. This structure matters because the effect attributed to a treatment can depend on the period and contrast being analyzed. A simple change over time within a group is not automatically evidence of a difference caused by the orthosis. Changes may reflect the assigned treatment, the occupational therapy approach, time, or other influences.

What does the primary score represent?

The COPM Performance score is based on participants' ratings of their ability to carry out selected tasks. The registry states that participants select 5 tasks and rate each on the specified scale, with the total described as the mean of individual task scores. A group mean would describe the average score for a group, while a standard deviation would describe the spread of scores around that mean. Neither summary, by itself, establishes a treatment effect. To compare groups, an analysis would need to define the quantity being compared, such as a difference in change or a difference at a specified assessment, and account for the study's repeated assessments as appropriate.

In general, repeated measurements from the same participant are related rather than independent. An analysis that treats them as unrelated can misstate uncertainty. Common approaches model the correlation among measurements or focus on a prespecified contrast, but the registry record does not report which approach was used. It also does not report whether baseline scores were included as covariates, how incomplete repeated measurements were handled, or whether any adjustment was made for differences in participant characteristics.

How should estimates and uncertainty be read?

A treatment estimate describes the observed contrast defined by an analysis. Its direction indicates which group had the higher score under the chosen coding, and its size describes the estimated magnitude in the endpoint's units. A confidence interval gives a range of values compatible with the data and the method's assumptions. A narrow interval indicates greater precision than a wide interval, while an interval that includes no difference can leave the direction and size uncertain. A p-value addresses compatibility of the data with a specified null model; it does not measure the probability that a treatment works, nor does it indicate the clinical importance of a difference.

These general concepts cannot be applied to the COPM comparison in this record because no estimate, interval, or p-value is reported. A standard deviation, even if reported, would describe participant-level variation rather than uncertainty in the treatment contrast. Uncertainty in a group contrast depends on the analysis and the available data, neither of which is described in sufficient detail.

What do the planning illustrations mean?

The registry record describes sample-size illustrations based on a fraction of the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. Such values are planning illustrations: they show what sample sizes would be associated with specified assumptions under the stated method. They are not observed power, and they do not demonstrate that the completed study had adequate power. The record does not report a trial-specific sample-size justification or identify a prospective effect size on which the design was based. The numerical planning outputs and the fractions used are not reported in the registry record.

In general, planning based on an observed effect should be interpreted cautiously, since the observed effect may be uncertain and can differ from the effect a future study is designed to detect. The illustration does not replace the observed estimate and its confidence interval. Here, the primary observed effect itself is not reported in the registry record, so no conclusion about the study's achieved precision can be drawn from the stated planning method.

Why can over-dispersion matter?

For count outcomes, over-dispersion means that variation is greater than a simple model assumes. If it is ignored, standard errors can be too small and confidence intervals too narrow. This is a general statistical issue, not a reported feature of this study's primary endpoint. The COPM is described as a continuous score summarized with a mean and standard deviation; the registry record does not report an over-dispersion assessment or a model for the primary analysis.

Overall, the design and endpoint definitions support a description of the intended comparison, but not a reconstruction of the analysis. The registry record does not report the model, inferential estimates, uncertainty measures, or participant-level analysis details needed to assess the statistical evidence for the primary question.

10. Multiplicity, Missing Data and Analysis Populations

The registry describes COPM change comparisons between Week 1 and Week 8, Week 1 and Week 15, and Week 8 and Week 15. It also lists a range of secondary movement and strength outcomes and states hypotheses concerning functional performance, forearm motion, and upper-extremity motor function. Considering several outcomes and time contrasts raises a multiplicity question: the chance of at least one apparently notable result can increase when many statistical tests are conducted. General methods for addressing this include prespecifying a primary contrast, adjusting for multiple comparisons, or treating secondary analyses as exploratory. The registry record does not report which strategy, if any, was used.

The record lists 21 outcome measures and 0 analyses. It does not provide a complete analysis plan or statistical results, so it is not possible to determine which comparisons were actually tested, whether outcomes were selected after examining data, or whether multiplicity adjustments were made.

Missing-data handling is also not reported in the registry record. There is no account of missing COPM assessments, reasons for missingness, imputation, or sensitivity analyses. These details matter because analyses based only on observed measurements can be biased when the availability of measurements relates to participants' outcomes or group assignment. The record does not allow assessment of that possibility.

The analysis population is not specified. The registry does not say whether results were intended to include all randomized participants, only those who completed assigned treatment, or another defined group. It gives enrollment and safety denominators, but does not identify the number contributing to each COPM comparison. As a result, the scope and robustness of any primary analysis cannot be evaluated from the registry record.

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 reports no serious adverse events among the participants listed as at risk in either group: Group A has 0 affected among 8 at risk, and Group B has 0 affected among 6 at risk. It also reports no other adverse events among those at risk in either group: Group A has 0 affected among 8 at risk, and Group B has 0 affected among 6 at risk. Deaths are recorded as 0 for both groups, and no top serious-event terms are listed.

These figures are the safety summaries recorded for the specified at-risk groups. They are not evidence that no event could occur, and they do not establish that the interventions have no safety risks. With no reported events, the summaries do not allow estimation of comparative risk or precise event rates. The record does not explain how these safety denominators relate to the enrollment figure, how adverse events were collected, or the criteria used to classify events. No inference about events beyond the registry's recorded follow-up and definitions should be made.

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

The registry record documents a randomized study of a forearm rotation orthosis and a task-oriented occupational therapy approach in people with a hemiparetic arm after stroke. It identifies the intervention sequences, the COPM Performance score as the primary outcome, and assessments at Week 1, 8, and 15. It also records safety summaries with no serious or other adverse events reported in the listed at-risk groups.

Those descriptions do not answer whether the orthosis changed self-perceived functional performance, whether the occupational therapy approach was associated with improvement, or whether either intervention affected the listed movement and strength outcomes. The primary scores, group contrasts, and uncertainty estimates are not reported in the registry record. Statistical significance, clinical importance, direction of effect, and precision therefore cannot be assessed.

Nor does the completed status establish that the study met its hypotheses. Completion describes the recorded status, not the direction or strength of the findings. The absence of recorded events in the safety summaries should not be read as proof of absence of risk, particularly without details about ascertainment and follow-up.

The record is useful for understanding the planned clinical question and the type of endpoint collected, but it is not a results report sufficient for judging efficacy or comparative safety. Any account of benefit, lack of benefit, or certainty would require outcome results and analysis details that are not reported in the registry record.

13. Why This Trial Matters Statistically

The statistical interest of this study lies in the relationship between treatment sequence, repeated measurement, and a patient-reported functional outcome. The COPM Performance score asks participants to rate their perceived ability to perform personally selected tasks. That is a different construct from the listed goniometric measurements and strength assessments. Keeping those outcomes distinct is important: a change in perceived task performance cannot be assumed to imply a corresponding change in joint movement or strength, and vice versa.

The treatment sequences also make the target comparison consequential. Both groups receive the task-oriented occupational therapy approach in the later listed period, while only Group A has the orthosis during that period. The interpretation depends on the time contrast, the treatment exposure, and how the analysis accounts for repeated assessments. The registry describes multiple change intervals but does not report a primary contrast or an analysis model.

The study highlights why outcome definitions and analysis plans matter alongside randomization. Randomization supports a comparative design, but the estimate and its uncertainty are necessary to evaluate what the data indicate. The registry record identifies 21 outcome measures and lists 0 analyses, without reporting outcome results, missing-data methods, or multiplicity handling. This leaves important statistical questions unresolved, including which comparisons were emphasized and how precision was assessed.

Finally, the stated planning illustrations are not a substitute for the observed results or a trial-specific sample-size justification. They are described as planning exercises based on a fraction of an observed effect, rather than as observed power. With no primary estimate reported in the registry record, the statistical evidence for the clinical question remains undocumented.

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 trial is that the registry record does not report the primary outcome data or statistical results. Without group summaries, changes, a between-group estimate, or a measure of uncertainty, the central comparison cannot be evaluated. The record lists 0 analyses, so there is no reported inferential analysis to interpret.

The design information is also incomplete. The record identifies randomized allocation, single masking, and a parallel model, but does not explain how the random sequence was generated or concealed, who was masked, or how adherence was assessed. It does not report baseline characteristics by group, making it impossible to evaluate the observed comparability of the groups.

Several outcome measures and time contrasts are described, but the record does not identify a prespecified primary comparison beyond naming the primary endpoint, nor does it report a multiplicity strategy. It does not describe missing observations, analysis populations, the statistical model, or sensitivity analyses. These omissions limit assessment of bias and the reliability of any unreported findings.

The enrollment figure and the at-risk denominators in the safety summaries are not reconciled in the registry record. The record does not specify why the denominators differ from enrollment or how many participants contributed to each primary outcome assessment. The stated sample-size illustrations are not accompanied by their numerical values or a trial-specific prospective justification. Finally, the registry's safety figures do not describe event ascertainment or follow-up details, which limits interpretation of the absence of recorded events.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Forearm Rotation Orthosis for Stroke — NCT01987414.
• Registry record last updated 2019-09-06; status last verified 2019-09.
• Results first posted 2019-09-06.
• 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.

18. Record Summary

NCT01987414 is a completed randomized, single-masked, parallel study of a forearm rotation orthosis for people with a hemiparetic arm after stroke. The record describes an enrollment of 18 and two treatment sequences: Group A received the orthosis followed by the orthosis with task-oriented occupational therapy, while Group B received no treatment followed by the occupational therapy approach.

The primary outcome was COPM Performance, assessed at Week 1, 8, and 15. The registry lists 21 outcome measures and 0 analyses. It does not report primary outcome results, statistical estimates, confidence intervals, p-values, missing-data methods, or the analysis population. Safety summaries record no serious or other adverse events and no deaths in either listed group. The registry record therefore describes the study design and intended measurements, but does not document the statistical results needed to judge the primary comparison.