This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Relationship Between Attention and Emotional Regulation Post-Traumatic Brain Injury (TBI) (NCT01681589), a randomized na study. The primary outcome is Baseline Measures Before Treatment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01681589 |
| Phase | NA |
| Condition | Traumatic Brain Injury |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 40 |
| Arms in the primary outcome | n/a |
| Lead sponsor | NYU Langone Health |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns patients with traumatic brain injury (TBI) who met the study’s participation criteria. The record also describes a healthy control group, with fifteen healthy control subjects. It does not give further participant characteristics or explain how the healthy controls contribute to the main treatment comparison.
Intervention
The experimental group was described as receiving active transcranial direct current stimulation (tDCS) for 20 minutes alongside computerized cognitive training twice a week for 30 minutes over 6 weeks. The stated aim was to investigate attention and emotional function after TBI and explore tDCS as a strategy for modulating activity in prefrontal-limbic circuits.
Comparator
The control group was described as receiving sham-tDCS and computerized cognitive training twice a week for 20 minutes over 6 weeks, with 12 training sessions. The record identifies a separate healthy control group but does not describe it as the randomized treatment comparator.
Primary question
The registry describes baseline testing of alertness, the ability to perform actions one after another, other mental functions, emotional control and brain connectivity. The broader study aim was to investigate the relationship between attention and emotional function after TBI and explore a stimulation-based treatment strategy. No study data are available in the registry record, so it does not establish whether these measures differed between groups or changed after treatment.
3. Trial Design
The registry record identifies this as a completed, randomized, double-masked, parallel-group study of tDCS after traumatic brain injury. The listed phase is not applicable. Enrollment is recorded as 40. The record does not give enough information to determine how that enrollment figure relates to the separately described healthy control group of fifteen subjects.
The experimental group was described as receiving active tDCS for 20 minutes and computerized cognitive training twice a week for 30 minutes over 6 weeks. The control group was described as receiving sham-tDCS and computerized training twice a week for 20 minutes over 6 weeks, for 12 training sessions. These descriptions do not establish further details about treatment delivery, adherence or whether the masking was maintained.
The study also included a healthy control group. The registry does not explain whether this group was randomized, what assessments it received, or how its data were intended to contribute to the analyses. The record identifies baseline assessment during Week 1 and describes post-treatment measures in a secondary outcome. It does not report results for either assessment.
The record gives a start date of 2012-08 and a primary completion date of 2019-06, and lists the study as completed. Completion status does not mean that results are available: the record states that no study data are available because the principal investigator and study team left the institution and efforts to contact them were unsuccessful. Further details of the conduct and analysis 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
| Stage | Control Group | Transcranial Direct Current Stimulator (TDCS) | Healthy Control Group |
|---|---|---|---|
| STARTED | 0 | 0 | 0 |
| COMPLETED | 0 | 0 | 0 |
| NOT COMPLETED | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: The PI and study team has left the institution. Efforts were made to contact the PI/study team members, but were unsuccessful. Data transfer was not ideal, and no study data are available.
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 PI and study team has left the institution. Efforts were made to contact the PI/study team members, but were unsuccessful. Data transfer was not ideal, and no study data are available.
| Characteristic | Unit | Control Group | Transcranial Direct Current Stimulator (TDCS) | Healthy Control Group | Total |
|---|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | 0 | |
| Sex: Female, Male: Female | — | — | — | — | |
| Sex: Female, Male: Male | — | — | — | — | |
| Race (NIH/OMB): American Indian or Alaska Native | — | — | — | — | |
| Race (NIH/OMB): Asian | — | — | — | — | |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | — | — | — | — | |
| Race (NIH/OMB): Black or African American | — | — | — | — | |
| Race (NIH/OMB): White | — | — | — | — | |
| Race (NIH/OMB): More than one race | — | — | — | — | |
| Race (NIH/OMB): Unknown or Not Reported | — | — | — | — | |
| Region of Enrollment: United States | participants | — | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as Baseline Measures Before Treatment, measured over Week 1.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary outcome is titled “Baseline Measures Before Treatment,” with a timeframe of Week 1. Its description says that patients meeting participation criteria would be assessed for alertness, the ability to perform actions one after another and other mental functions. It also describes testing emotional control and obtaining an MRI to help investigators understand how parts of the brain are connected.
These measures address the study’s stated interest in attention, emotional function and neural circuitry after TBI. They can characterize abilities at baseline and provide information relevant to the study’s broader research question. The registry description, however, does not identify a single score, scale, unit or summary measure, nor does it specify how the different assessments would be combined or compared. The primary outcome therefore cannot be interpreted as one defined numerical endpoint from the registry record.
The description concerns baseline assessments before treatment, rather than a reported post-treatment change or treatment-group contrast. The registry record notes that the primary outcome has several categories or time points and was not reduced to one comparison. No study data are available, and numerical outcome results, estimates of change and measures of precision are not reported in the registry record. The role of each individual test in the planned primary analysis is also not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The main interpretive constraint is the absence of study data. The registry record states that no study data are available after the study team left the institution and attempts to contact team members were unsuccessful. Although the study is listed as completed, completion status does not supply an outcome estimate. There are no reported group results from which to assess the relationship between attention and emotional regulation, the effects of active versus sham stimulation, or changes from baseline.
The primary outcome description covers several types of assessment, including alertness, sequential actions, other mental functions, emotional control and MRI-based assessment of brain connectivity. These are not presented as a single score or one defined comparison. The registry itself notes that the primary outcome has several categories or time points and was not reduced to a single comparison. Consequently, there is no specific primary contrast to interpret statistically in the posted results.
The randomized, double-masked, parallel-group design describes how a treatment comparison was intended to be organized. Randomization can support comparability of groups in expectation, while masking can limit some forms of influence on assessment or reporting. Neither feature supplies evidence about the observed groups, the success of masking, participant adherence or outcome differences. Those details are not reported in the registry record.
The registry lists zero serious and zero other adverse events for each of the three groups. These entries are counts in the record, not a substitute for study data or a complete account of safety monitoring. In particular, the record also states that no study data are available. The event entries therefore cannot be used to infer that no events occurred during the study or to compare event risks between groups.
No estimates, confidence intervals, hypothesis tests or analysis results are reported in the registry record. Statistical significance and precision cannot be assessed. There is also no reported analysis population, accounting of participants by group, or explanation of missing observations. The enrollment figure alone does not reveal how many participants were assessed, treated or included in any intended analysis.
Thus, the registry supports a description of the study’s purpose and intended design, but not a conclusion about efficacy, the size or direction of any effect, or the strength of evidence for an association. The proposed research question remains unanswered in the posted results.
9. Statistical Methods Explained
What does randomization contribute? In general, randomization assigns participants to groups using a chance-based process. It is intended to reduce systematic differences between groups at the time of assignment, including differences that investigators may not have measured. It does not guarantee that groups will be identical, especially in a pilot study, and it does not address bias caused by missing outcomes or differences in treatment received. The registry identifies the study as randomized but does not report the randomization method, allocation concealment or group-specific participant counts.
What does masking mean? In general, masking is intended to limit the influence of knowing a treatment assignment on participants, investigators or outcome assessors. The record labels the study double-masked and describes a sham-tDCS control. It does not identify who was masked, explain how masking was implemented, or report whether participants or study staff could guess the assignment. Those implementation details are not reported in the registry record.
What is the intended treatment contrast? In general, a treatment contrast compares outcomes between groups assigned to different study conditions. The listed experimental and control conditions differ in active versus sham tDCS and in the stated duration of computerized training. The registry does not specify a single numerical endpoint or report a group comparison. It also does not explain how the healthy control group fits into a treatment-effect analysis. The design description therefore does not, by itself, define a result that can be estimated from the posted record.
Why does endpoint definition matter? A statistical analysis needs a clear outcome: for example, a specified score at a defined time, or a defined change between assessments. The primary outcome description includes multiple kinds of tests and an MRI assessment, but gives no unit, score, scoring rule or single summary. General statistical interpretation depends on knowing what is measured and how it is summarized. Without that detail, readers cannot tell what a hypothetical effect estimate would represent or compare it meaningfully across participants.
How should estimates and uncertainty be read? In general, an estimate describes the observed value of a quantity of interest, such as a difference between groups. A confidence interval describes the uncertainty around an estimate under the assumptions of the statistical method. A narrow interval indicates greater precision than a wide interval, but neither precision nor an interval can be judged without reported estimates and data. No effect estimates or confidence intervals are reported in the registry record. There is consequently no basis for assessing magnitude, direction or precision.
What would a significance test tell a reader? In general, a hypothesis test evaluates how compatible data are with a specified null hypothesis under a statistical model. A p-value does not measure the size or clinical importance of an effect, and it does not establish that a finding is true. The registry does not report a test, p-value or analysis plan. The planning assumptions describe a two-sided significance level of 0.05 for an illustration based on an observed effect, but the registry record contains no study data from which that effect can be interpreted. That assumption should not be mistaken for a reported trial analysis or a protocol commitment.
Why can outcome distributions affect analysis? In general, the choice of a statistical method depends on the outcome’s scale and distribution. Continuous scores, counts, categories and repeated measurements can require different approaches. If count data vary more than a basic model assumes, over-dispersion can lead to uncertainty estimates that are too small unless the model accounts for that extra variation. This is a general consideration, not a reported feature of this study. The registry does not report outcome distributions, a statistical model, covariate adjustment or any analysis results.
What do planning calculations mean? In general, a sample-size calculation uses assumptions about a target effect, variability, significance level and desired power to illustrate how much information a study might need. Such calculations are planning illustrations, not observed power and not evidence that a study detected an effect. The record’s planning description refers to equal allocation between two arms, a normal approximation and a stated fraction of an observed effect. Because no study data or observed effect are available in the registry record, these assumptions cannot be evaluated as a description of a trial result or the study’s own design justification. The protocol’s sample-size justification is not reported in the registry record.
What can be learned from this record statistically? It documents broad design features and the intended measurement domains, but not the data needed to estimate effects or uncertainty. The statistical analysis plan, interim analyses, model specifications and procedures for interpreting multiple outcomes are not reported in the registry record. No trial-level inferential conclusion can be recovered from design labels alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry describes a primary outcome with several categories or time points and does not reduce it to one comparison. It also lists a secondary outcome called “Post Treatment Measures to Check Improvements.” The assessments span attention-related functions, emotional control and MRI-based connectivity. When a study considers multiple outcomes, time points or comparisons, the chance of at least one apparently unusual result can increase. In general, a prespecified analysis plan can clarify which outcomes are primary and how multiple tests will be handled.
Multiplicity procedures, outcome hierarchies and any approach to controlling the overall error rate are not reported in the registry record. The record does not specify which assessment was intended to anchor an efficacy claim, whether outcomes were intended as separate tests, or how any correlated measures would be handled. As a result, a reader cannot determine how a hypothetical positive result across several measures would have been interpreted.
Missing-data procedures are also not reported in the registry record. The record states that no study data are available, so it provides no participant-level accounting, outcome completion rates, reasons for missing assessments or methods for handling incomplete observations. The analysis populations—such as whether analyses were intended to include all randomized participants or only those completing treatment—are not reported in the registry record.
These omissions matter because missing outcomes and selective emphasis among multiple measures can affect what an analysis represents. Without an analysis plan, participant flow or outcome data, neither the robustness of results nor the consequences of missingness can be evaluated.
11. What the Result Does, and Does Not, Mean
The record establishes that investigators planned a randomized, double-masked, parallel-group pilot study involving active tDCS, sham-tDCS and a healthy control group. It describes an interest in attention, emotional regulation and brain connectivity after TBI, along with baseline assessments and post-treatment measures. These registry entries describe the research question and intended study structure; they are not findings about participants’ outcomes.
The registry does not report an effect estimate for active versus sham stimulation, a change in attention or emotional regulation, or a relationship between attention and emotional function. It also does not report whether brain connectivity differed across assessments or groups. No study data are available, so the direction, size and precision of any possible effects cannot be determined from the posted results.
The study’s completed status should not be read as evidence that its intended outcomes were achieved, that treatment effects were absent, or that the findings were inconclusive. It indicates the status recorded for the study, while the record separately states that data are unavailable. Those are different kinds of information.
The event entries list zero serious and zero other adverse events for each group, but the record does not provide study data to support a broader safety interpretation. These entries do not establish that no events occurred or that the groups had equivalent safety outcomes.
In general, a randomized design can support causal comparisons when it is implemented and analyzed appropriately, but a design description alone is not a treatment result. The posted record therefore documents an intended investigation, not evidence for or against a treatment effect or a clinical conclusion.
12. Why This Trial Matters Statistically
This study raises a useful statistical challenge: its research question spans several related but distinct domains. Attention, emotional regulation and brain connectivity are not interchangeable outcomes. Clear outcome definitions are essential for deciding what is being estimated, selecting a suitable analysis and interpreting any result in relation to the study’s aims.
The record also illustrates why study status and statistical evidence must be kept separate. A study can be listed as completed while its outcome data remain unavailable. Without data, readers cannot evaluate group comparability, adherence, outcome completeness, effect size or precision. The randomized and masked design labels describe intended safeguards; they do not replace an analysis of what happened.
The distinction between a treatment comparator and a healthy reference group is another important design issue. The registry describes both a sham control and healthy controls, but does not explain the healthy group’s role in the intended analyses. A clear account of which groups answer which research questions helps prevent readers from treating every group as part of the same treatment contrast.
Finally, a primary outcome described across multiple categories or time points requires transparent prespecification and multiplicity planning. Without a defined primary measure and analysis plan, the interpretation of possible findings would be difficult even if results were available. The record therefore highlights how endpoint definition, analysis transparency and data availability are necessary complements to a trial’s design.
13. 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 central trial-specific limitation is that the registry states no study data are available. It attributes this to the principal investigator and study team having left the institution, unsuccessful efforts to contact them and an imperfect data transfer. Consequently, there are no reported participant-level or group-level outcome results to evaluate.
The primary outcome is described broadly rather than as a single defined measure. Its description includes alertness, sequential actions, other mental functions, emotional control and MRI-based assessment, while the record notes several categories or time points and does not reduce the outcome to one comparison. Units, scoring rules and a primary statistical contrast are not reported in the registry record.
The enrollment figure is 40, while the intervention descriptions separately mention fifteen healthy control subjects. The registry does not explain the relationship between those figures or provide group-specific enrollment and analysis counts. Participant characteristics, eligibility details beyond meeting study criteria, allocation details, adherence and reasons for withdrawal are not reported in the registry record.
The intervention descriptions specify different training durations for the active and sham groups, but further information about treatment implementation is not reported in the registry record. The record also does not identify who was masked or whether masking was maintained. Statistical methods, handling of missing data, analysis populations, multiplicity procedures, interim analyses and the protocol’s sample-size justification are not reported in the registry record.
These limitations prevent assessment of the magnitude or precision of any treatment effect, the completeness of the data, and the robustness of a statistical analysis. The recorded zero adverse-event counts do not resolve the lack of study data.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Relationship Between Attention and Emotional Regulation Post-Traumatic Brain Injury (TBI) — NCT01681589.
- Registry record last updated 2020-08-21; status last verified 2020-08.
- Results first posted 2020-08-21.
- 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.
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17. Record Summary
The registry describes a completed randomized, double-masked, parallel-group study of tDCS in the context of attention and emotional regulation after TBI. Enrollment is recorded as 40. The experimental condition involved active tDCS and computerized cognitive training; the control condition involved sham-tDCS and computerized training. A healthy control group of fifteen subjects is also described.
The primary outcome is titled “Baseline Measures Before Treatment” and covers several assessment domains during Week 1. A secondary outcome refers to post-treatment measures. The registry does not report a single primary comparison, statistical analysis results or numerical outcome estimates.
The record states that no study data are available following the study team’s departure from the institution and unsuccessful contact efforts. Therefore, the posted information supports description of the study’s aims and design, but not an assessment of treatment effects, statistical precision or a clinical conclusion.