Customized Cortical Stimulation Therapy in the Rehabilitation of Stroke Patients: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Customized Cortical Stimulation Therapy in the Rehabilitation of Stroke Patients (NCT02544503), a non-randomized na study. The primary outcome is Mean Motor Evoked Potential (MEP) Amplitudes Assessed by Stimulus Response Curve (SRC) of the Contralesional M1.

2. Clinical Question

3. Trial Design

The registry identifies this as a non-randomized, double-masked, parallel-group study sponsored by Emory University. Its listed condition is stroke. The study was started on 2015-11-05, had a primary completion date of 2021-02-04, and is listed as terminated. Enrollment is recorded as 100; the reason for termination and the relationship between that enrollment figure and the number completing assessments are not reported in the registry record.

The two described groups are Stroke Patients and Healthy Controls. The stroke-patient description says participants undergo single-pulse TMS, paired-pulse TMS, and low-frequency repetitive TMS at one month and six months post stroke. The healthy-control description says participants undergo those procedures at one month and six months. Separately, the primary endpoint timeframe describes a single study visit for healthy controls. These descriptions do not fully align, and the record does not clarify the control-group schedule.

Sham Motor Cortex Stimulation is among the listed interventions, but the arm descriptions do not specify its role, assignment, or comparison. Non-randomized allocation means that the groups were not formed by random assignment, and the registry explicitly cautions that they are not a like-for-like control comparison. Double masking is listed, but the record does not identify who was masked or how masking was maintained. The study phase is listed as NA. Further design details, including the reason for termination and the planned analysis procedures, 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.

Before assignment: Individuals provided consent to participate and were enrolled into study arms based on their health status (prior stroke or health control). After enrolling, 24 individuals with stroke and 3 healthy controls did not meet eligibility criteria and did not participate in any study assessments. Participants with stroke were assessed one and six months after their stroke, while healthy controls participated in a single assessment.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: This analysis includes participants who completed this assessment at the indicated study visit.

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: The baseline analysis presented here includes participants who met eligibility criteria.

6. Primary Endpoint

The registry lists the primary outcome as Mean Motor Evoked Potential (MEP) Amplitudes Assessed by Stimulus Response Curve (SRC) of the Contralesional M1, measured over 1 month post-stroke (subacute stroke) or single study visit for healthy controls, 6 months post-stroke (chronic stroke).

The primary endpoint is mean motor-evoked-potential (MEP) amplitude, measured in mV, in the contralesional M1 using a stimulus-response curve (SRC). MEPs are responses elicited by stimulation of the motor system. In this study, measurements at different stimulus intensities are used to characterize the response curve rather than relying on a single intensity. The endpoint description says that the mean amplitude at each intensity is calculated and that the sum of those means is used as the area under the curve.

The registry frames this measure around changes in the response across stimulus intensities. It specifies a time point of one month post-stroke for subacute stroke, a single study visit for healthy controls, and six months post-stroke for chronic stroke. The stated analysis population includes participants who completed the assessment at the indicated time point. The record does not provide the numerical MEP means, variability, curve areas, or contrasts between groups or time points. It therefore establishes what was intended to be measured, but does not show the size or precision of an observed primary-endpoint result.

In general, a curve-based measure can represent response over a range of stimulation intensities. Its interpretation depends on the measurement procedure and the analysis definition; the registry record does not report additional details about curve fitting or the handling of incomplete intensity measurements.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The record identifies the primary outcome as a continuous measure summarized by a mean, with standard deviation as the stated measure of dispersion. It describes a stimulus-response curve across stimulus intensities and says that the intensity-specific means are summed to obtain the area under the curve. It does not report the numerical outcome values or a detailed statistical analysis plan. The explanations below describe general statistical concepts and do not imply that a particular method was used in this study.

What does a mean and standard deviation describe?

In general, a mean gives the average value of a measurement in the participants included in an analysis. A standard deviation describes how spread out individual measurements are around that average. These quantities answer different questions: the mean describes the group’s central level, while the standard deviation describes participant-to-participant variability. The standard deviation is not the same as the uncertainty in the estimated mean. To assess uncertainty in a mean or a contrast, readers would need an appropriate standard error or confidence interval, neither of which is reported for the primary endpoint in the registry record.

The endpoint description refers to means at each stimulus intensity and a sum used as the area under the curve. In general, summarizing a response across intensities can retain information about the overall response pattern. Interpretation depends on which intensities are included and how observations at each intensity are collected and handled. Details about those procedures, the number of measurements, and the handling of incomplete curves are not reported in the registry record. No curve values or derived area estimates are reported, so the shape or magnitude of the response cannot be assessed.

Why does the design affect interpretation?

In general, randomization is used to make assigned groups comparable on average with respect to both measured and unmeasured characteristics. This study is listed as non-randomized, and its stroke-patient and healthy-control groups are not a like-for-like control comparison. As a result, group differences cannot automatically be attributed to stimulation or to stroke status alone. The record does not describe adjustment methods that might account for measured differences between groups.

The study is listed as double-masked, but masking is distinct from randomization. In general, masking can reduce the influence of expectations on some aspects of study conduct or assessment. It does not by itself ensure comparable groups, and the registry does not specify which people were masked or how masking was implemented. The parallel model indicates groups are described in parallel, but the record does not give a full allocation or analysis procedure.

How should time points and repeated measurements be considered?

The primary endpoint description includes one month post-stroke and six months post-stroke for stroke patients, and describes a single study visit for healthy controls. The arm description for healthy controls, however, refers to procedures at one month and six months. The record does not resolve this difference in wording. It also does not report whether the primary analysis compared time points within participants, compared groups at particular time points, or used another approach. In general, repeated measurements from the same participant are related rather than independent. Statistical analyses of such data need to account for that relationship when making estimates and calculating uncertainty.

The endpoint population is described as participants completing the assessment at the indicated time point. This identifies completion as relevant to inclusion, but does not say how many participants were assessed at each time point or how missing observations were handled. In general, analysis restricted to completers can be affected if completion is related to participant characteristics or outcomes. Other approaches may use different assumptions about missing data. The analysis method and assumptions are not reported in the registry record.

What can be inferred from the listed analysis information?

The registry lists 12 outcome measures and zero analyses. These entries do not provide estimates, uncertainty intervals, test statistics, or p-values. The record does not report a statistical analysis plan, a primary contrast, covariate adjustments, or procedures for repeated measurements. It also does not report interim analyses or a sample-size justification. Without those details and numerical results, readers cannot determine how the outcome measures were analyzed or how strongly the data support any particular interpretation.

In general, a confidence interval gives a range of estimates compatible with observed data under stated statistical assumptions. Its width reflects precision: a narrower interval indicates greater precision than a wider interval, all else being equal. A p-value, when reported, addresses how compatible data are with a specified null model; it does not quantify the size or importance of an effect. Neither type of result is reported for the primary endpoint in the registry record, so no inferential conclusion can be drawn from those concepts alone.

What do the planning assumptions mean?

The record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. These are assumptions for a planning calculation, not a report of the trial’s observed power. The record does not report a sample-size justification from the trial’s own design. Numerical planning outputs and the observed effect used for the illustration are not reported in the registry record, so the illustration cannot be evaluated from these details alone.

In general, planning calculations estimate the number of participants needed under specified assumptions about the target effect, variability, significance level, and desired power. They do not establish that a study actually achieved that power, and they cannot substitute for an estimate and uncertainty interval based on observed results. The registry’s planning description should therefore be kept separate from the study’s enrollment and from any claim about the evidential strength of an endpoint result.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 12 outcome measures, including the primary MEP amplitude endpoint and secondary measures involving motor function, paretic-arm use, lesion load, M1 activity, cortical inhibition, and wrist-extension velocity. It lists zero analyses. The number of outcomes means that multiple questions were registered, but the record does not say which outcomes were analyzed or how their results were interpreted together. The zero analyses entry is not evidence that analyses were never performed; it means no analyses are listed in the registry record.

When multiple outcomes, time points, or comparisons are examined, the chance of at least one apparently notable finding can increase. In general, multiplicity procedures can adjust how evidence is evaluated across several tests, or investigators can identify a limited set of prespecified primary comparisons. The registry does not report a multiplicity adjustment, a hierarchy among secondary outcomes, or a detailed statistical analysis plan. It is therefore not possible to determine how the study handled the potential for multiple comparisons.

Missing-data information is also limited. The primary endpoint description defines its analysis population as participants completing the assessment at the indicated time point, but the record does not provide completion counts by group or time point, reasons for missing measurements, or an imputation or other missing-data method. In general, results from participants with completed assessments can differ from results that would have been obtained from all enrolled participants if missingness is related to participant characteristics or outcomes. The available information does not allow that possibility to be evaluated.

The record does not report whether analyses followed an intention-to-treat approach, whether participants were excluded after enrollment, or how repeated observations were handled. Those analysis-population and missing-data details are not reported in 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.

Most frequent non-serious adverse event terms

The registry reports serious adverse events for two groups. Among Stroke Patients, 42 were listed as at risk and 0 as affected by a serious adverse event; deaths were 0. Among Healthy Controls, 31 were listed as at risk and 0 as affected by a serious adverse event; deaths were 0. These are descriptive counts within the registry’s reported groups. They do not establish that risk was absent, nor do they provide a comparative estimate of safety between groups.

For other adverse events, the record reports 14 affected among 42 at risk in the Stroke Patients group and 1 affected among 31 at risk in the Healthy Controls group. The record does not list the specific terms for these other events in the adverse-event information. It also does not provide event timing, severity details for these events, attribution to stimulation, or an analysis comparing groups. The counts should therefore be read as registry-reported event counts, not as evidence that a particular intervention caused or prevented an event.

The group sizes at risk in the safety information are not the same as a complete account of enrollment or assessment completion. The registry does not explain how participants entered the safety population or whether follow-up differed across groups. These counts alone cannot resolve those questions.

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

The record establishes that a study was designed to examine cortical stimulation and motor-system measurements in stroke patients and healthy controls. Its primary endpoint was defined as mean MEP amplitude across stimulus intensities in contralesional M1, with intensity-specific means summed to form an area-under-the-curve measure. The record also lists motor-function and imaging-related secondary outcomes. This describes the study’s intended measurement focus, not a finding that any measure changed.

The registry lists the study as terminated and records enrollment of 100. It does not report why the study was terminated, how many participants completed each assessment, or numerical results for the primary endpoint. Without those results, readers cannot determine the observed direction or size of a difference, its precision, or whether findings were consistent across participants. No estimate should be inferred from the endpoint definition or from the study status.

The non-randomized design is important to interpretation. Stroke patients and healthy controls differ by the condition being studied, and the registry explicitly says that the arms are not a like-for-like control comparison. Any observed difference between groups, if one were reported, would need interpretation in light of this design rather than being treated automatically as a causal effect of stimulation. The record does not report an adjusted comparison that could address measured group differences.

The safety counts are descriptive: the registry reports 0 serious adverse events in each group, and reports other adverse events in both groups. They do not establish a comparative safety effect, and details of the other events are not reported. Overall, the registry record supports a description of the question, design, outcome definitions, and recorded safety counts. It does not support a conclusion about whether a stimulation approach changed motor function or MEP amplitude, or about the certainty of any such change.

13. Why This Trial Matters Statistically

This trial is statistically notable for the way its question connects a physiological measurement to a broader rehabilitation context. The primary endpoint is not a direct motor-function score: it is a curve-based measure of MEP amplitudes in contralesional M1. The registry also lists functional measures, including time to complete the Wolf Motor Function Test, grip strength during that test, and use of the paretic arm assessed by the Motor Activity Log. Keeping physiological and functional outcomes distinct is important when interpreting what any eventual result would mean.

The non-randomized design also makes careful comparison essential. The registry identifies stroke patients and healthy controls but cautions that their arms are not a like-for-like control comparison. In general, a group contrast in such a design can combine differences associated with the groups’ clinical status and other factors. This is a reason to avoid reading a simple contrast as a causal treatment effect.

The record’s endpoint definition and safety counts offer useful context, but numerical primary results and a detailed analysis plan are not reported. The study is listed as terminated, and the reason is not reported in the registry record. These gaps illustrate why registry descriptions, observed estimates, and analysis details serve different roles: design information explains what was intended, while estimates and their uncertainty are needed to assess what the data show.

The entry also lists 12 outcomes and zero analyses. In general, when several outcomes and time points are considered, transparent reporting of prespecified analyses and multiplicity handling helps readers distinguish confirmatory questions from exploratory ones. Those details are not reported. The statistical importance of this record is therefore chiefly in clarifying the intended measurement and the limits imposed by the available results information, rather than in supporting a quantitative conclusion.

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 numerical results for the primary endpoint, including group means, standard deviations, curve areas, contrasts, or uncertainty intervals. It also does not report p-values or other test statistics. As a result, the magnitude and precision of any primary finding cannot be assessed from the record. The study is listed as terminated, but the reason for termination is not reported.

Allocation is non-randomized, and the registry cautions that the study arms are not a like-for-like control comparison. The record does not describe adjustment methods or other strategies for accounting for differences between stroke patients and healthy controls. Although double masking is listed, the people masked and the procedures used to maintain masking are not reported.

The intervention descriptions list sham motor cortex stimulation, but the group descriptions do not explain how sham stimulation fits into the study. The timing descriptions for healthy controls are also not fully aligned: the arm description refers to one month and six months, while the primary endpoint timeframe specifies a single study visit. The record does not clarify this schedule.

Further limitations in interpretation arise from unavailable analysis details. The statistical plan, multiplicity approach, handling of missing data, analysis populations beyond endpoint completers, and sample-size justification are not reported in the registry record. The record lists 12 outcome measures and zero analyses, but does not provide outcome-level results. Safety reporting includes counts, but details for other adverse events and a comparative safety analysis are not reported.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Customized Cortical Stimulation Therapy in the Rehabilitation of Stroke Patients — NCT02544503.
• Registry record last updated 2023-08-31; status last verified 2023-08.
• Results first posted 2022-08-23.
• 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 record for NCT02544503 describes Customized Cortical Stimulation Therapy in the Rehabilitation of Stroke Patients, sponsored by Emory University. The listed condition is stroke, the phase is NA, and the study is described as non-randomized, double-masked, and parallel-group. Enrollment is recorded as 100. The study started on 2015-11-05, had a primary completion date of 2021-02-04, and is listed as terminated.

The primary endpoint is mean MEP amplitude across stimulus intensities in contralesional M1, with a stated curve-area calculation. The record lists 12 outcome measures and zero analyses. It reports adverse-event counts but does not provide numerical primary-endpoint results or a detailed statistical analysis plan. The reason for termination is not reported in the registry record.