LED Therapy for the Treatment of Concussive Brain Injury: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for LED Therapy for the Treatment of Concussive Brain Injury (NCT02383472), a randomized na study. The primary outcome is Mean Difference in Change in Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Score at Baseline and 6 Weeks..

2. Clinical Question

The study concerns patients with persistent cognitive symptoms after mild traumatic brain injury, rather than an undifferentiated concussion population. The registry describes a randomized comparison of LED therapy with placebo and identifies the primary endpoint as change in Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores from study entry to week 6.

The endpoint includes verbal memory, visual memory, visual motor speed, reaction time, and symptom score. Those components do not all share the same direction of improvement: higher scores are described as better for verbal memory, visual memory, and visual motor speed, while lower reaction time and symptom scores are described as better. Interpretation therefore depends on which component is being considered, as well as the sign convention used for change.

The registry lists secondary outcomes involving D-KEFS performance, post-concussion symptoms, and cognitive symptoms at weeks 3 and 6. However, it contains no analysis entries, and the primary endpoint was not reduced to a single comparison in the registry results. Consequently, the clinical question can be described, but the posted record does not establish the observed size, direction, or precision of the treatment-group differences.

3. Trial Design

The registry classifies this as a randomized, parallel-group trial with quadruple masking. Its brief summary calls it a double-blind randomized trial, while the registry's masking classification is quadruple. The record does not explain which roles were masked or how masking was implemented, so the difference in wording cannot be clarified from the registry.

Enrollment is recorded as 53 participants. The registry marks the study completed, with a start date of 2012-09 and primary completion of 2016-05. The phase is listed as NA. Boston Children's Hospital is the sponsor.

Participants were to receive either the MedX Health Console model 1100 LED intervention or a placebo using the MedX Health Console model 1100-placebo. The treatment description specifies LED sessions over 6 weeks, 3 times per week, for a total of 18 visits, at Boston Children's Hospital. The placebo description says that participants followed the same schedule. The registry descriptions are truncated after some details about application, so the remaining device procedures are not reported in the registry record.

The brief summary states that both groups would complete D-KEFS and ImPACT assessments at study entry and at weeks 3 and 6, or earlier if symptoms resolved before the end of the 6 week period. The primary outcome is framed as change from baseline to 6 weeks. The record does not describe the randomization sequence, allocation concealment, masking procedures, adherence, or how earlier assessments were incorporated into the primary analysis.

The enrolled total and the adverse-event denominators are recorded, but the registry does not provide analyzed participant counts for the primary or secondary outcomes. The trial's intended comparison is clear; the analysis population and outcome-specific participant flow 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

Reasons for not completing this period:

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 Mean Difference in Change in Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) Score at Baseline and 6 Weeks., measured over From baseline to 6 weeks.

The primary endpoint is the mean difference in change in Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores between study entry and 6 weeks. The registry describes five composite scores: verbal memory, visual memory, visual motor speed, reaction time, and symptom score. The stated change is calculated as the entry score minus the 6-week score, and the trial's primary comparison is between the LED and placebo groups.

These measures cover different aspects of cognition and post-concussion symptoms. The registry identifies score ranges for each component: verbal memory and visual memory range from 0-100, visual motor speed from 0-60, reaction time from 0-1.0, and symptom score from 0-132. It also states that higher verbal memory, visual memory, and visual motor speed scores represent a better outcome, whereas lower reaction time and symptom scores represent a better outcome.

In general, a continuous endpoint can describe the size and direction of a measured change, while a comparison between groups can help distinguish change over time from change that also occurs under placebo. The five ImPACT components require separate interpretation because their scales and favorable directions differ. The registry does not report the component-level estimates, the statistical method used to combine or compare them, or a single overall treatment-effect estimate. Therefore, the endpoint definition is available, but its observed results and precision are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods cannot be fully reconstructed from the registry entry. The record specifies a randomized, parallel design with quadruple masking and identifies continuous outcomes summarized as means with standard deviations. It does not report the statistical analysis plan, the model used for the primary endpoint, the handling of repeated assessments, or the approach to missing outcome data.

What does a mean difference describe?

General explanation: A mean is an average of measured values. A mean difference compares averages between groups or compares average changes, depending on how the endpoint is defined. In this trial, the primary outcome is described as the mean difference in change in ImPACT scores between entry and week 6, with change defined as entry score minus 6-week score. For a treatment comparison, the group contrast would need to be interpreted alongside the direction of each score's favorable outcome. The registry does not post the group means, changes, or resulting contrast.

A standard deviation describes variation among individual observations around a group mean. It is not the same as the uncertainty in the mean or in a between-group contrast. General explanation: a confidence interval for a mean difference combines information about the estimate and its uncertainty under a statistical method. Wider intervals generally indicate less precision than narrower intervals. No confidence interval is reported for the primary outcome in the registry record.

Why do the outcome scales matter?

The five ImPACT components are not interchangeable measurements on one common scale. The record gives separate ranges and states that higher values are favorable for verbal memory, visual memory, and visual motor speed, while lower values are favorable for reaction time and symptom score. A positive change defined as entry minus week 6 would therefore not have the same interpretation across every component. For example, the sign of a change must be read with the measure's specified direction in mind. The record does not report a method for combining the components into one summary result.

General explanation: when multiple outcomes are examined, each can raise a separate chance of a false-positive finding if conventional significance tests are applied without adjustment. Statistical approaches to multiplicity may define one primary test, adjust thresholds, or use other prespecified strategies. The registry lists multiple primary components and multiple secondary outcomes, but does not report a multiplicity strategy. It is therefore not possible to tell from the registry which comparisons were treated as confirmatory or how any multiple testing was addressed.

How should repeated assessments be considered?

The brief summary describes assessments at entry and at weeks 3 and 6, or earlier if symptoms resolved before the end of the 6 week period. Repeated measurements can be analyzed in different ways. General explanation: a model using all repeated measurements can account for the fact that assessments from the same participant are related, whereas an analysis of change at a selected time point focuses on that time point. The appropriate interpretation depends on the prespecified estimand and analysis method. The registry defines the primary endpoint using baseline and week 6, but does not report whether intermediate observations were included in the analysis or how early assessments were treated.

General explanation: over-dispersion refers to variability greater than assumed by a statistical model. It matters when the model's uncertainty estimates rely on a variance assumption that does not fit the data, because uncertainty can then be understated or otherwise mischaracterized. The primary outcome is described as continuous, and the registry does not identify an over-dispersion issue or report a model that would allow its assessment. No claim about over-dispersion in this trial can be made from the registry record.

What do the planning assumptions mean?

The registry's sample-size-assumptions statement describes planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. It also distinguishes participants per arm for non-time-to-event outcomes from total event counts for time-to-event outcomes; the primary endpoint is continuous, not described as time-to-event. The numerical planning results are not reported in the registry record for this analysis, and the record does not provide the trial's own sample-size justification.

General explanation: a planning calculation estimates the sample size needed under specified assumptions. It is not an observed finding. In particular, an observed-effect-based illustration does not demonstrate that the trial had a particular probability of detecting an effect after the fact. Sample sizes in planning illustrations are not observed power. Because the primary result is absent, no posted primary effect estimate can be compared with those assumptions.

Which analysis details remain unknown?

The registry does not report the exact statistical test or model, covariate adjustments, confidence-interval method, analysis population, treatment of protocol deviations, missing-data method, or sensitivity analyses. It records zero analyses and notes that the primary endpoint was not reduced to one comparison. Those omissions prevent an independent reading of the primary statistical result because no result is posted and the analysis procedure is not described. General statistical principles can explain what these methods would do, but they cannot identify which methods were used in this trial.

10. Multiplicity, Missing Data and Analysis Populations

The registry identifies a primary endpoint with five ImPACT composite scores and lists secondary outcomes covering D-KEFS performance, post-concussion symptoms, and cognitive symptoms at weeks 3 and 6. It also records five outcome measures overall and zero analyses. The registry says that the primary outcome has several categories or time points and was not reduced to one comparison. No multiplicity adjustment or hierarchy among component outcomes is reported.

General explanation: multiplicity arises when several hypotheses or outcomes are examined. Without a prespecified strategy, a reader cannot determine whether a reported isolated finding would be confirmatory or exploratory, or how the overall false-positive risk was handled. Since the registry contains no outcome analyses, it is not possible to assess the practical effect of multiplicity on results in this trial.

The brief summary says assessments were planned at entry, week 3, and week 6, or earlier if symptoms resolved. The record does not explain whether early assessments replaced week-6 measurements, how unavailable assessments were handled, or what imputation or other missing-data method was used. Outcome-specific participant counts and analysis populations are not reported. Enrollment of 53 does not establish how many participants contributed data to any particular endpoint or time point.

The record also does not report whether the analysis followed an intention-to-treat population, a per-protocol population, or another definition. These are important distinctions because they specify which randomized participants are included and how treatment assignment is represented. Without the population definition and missing-data approach, readers cannot assess the potential effects of exclusions or incomplete follow-up on estimates. The lack of this information is a limitation of the registry record; it is not evidence that any particular method was or was not used outside the record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

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 23 participants at risk in the MedX Health Console Model 1100 group and 30 participants at risk in the placebo group. It records 0 serious adverse events in each group. The death counts are not reported in the registry record. No top serious-event terms are listed.

For other adverse events, the registry reports 1 affected participant among 23 at risk in the LED group and 0 among 30 at risk in the placebo group. These are participant counts, not event rates calculated here, and the registry does not provide further detail about the non-serious event in the LED group.

General explanation: an adverse-event count is interpreted in light of the observation period, event definitions, completeness of reporting, and the size of the groups. Zero recorded serious events does not demonstrate that an event is impossible, and small group counts can leave substantial uncertainty about uncommon outcomes. The registry does not report additional safety-analysis details, event timing, severity categories beyond serious versus other events, or causal assessments. These counts describe what is posted and should not be read as a complete characterization of safety.

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

The registry record establishes that a randomized, parallel-group comparison of LED therapy and placebo was conducted in a population described as patients with mild traumatic brain injury and cognitive symptoms lasting greater than 4 weeks. It also records the intervention schedule, the ImPACT-based primary endpoint, several secondary outcomes, enrollment of 53, and selected adverse-event counts. These details explain what the study set out to assess.

The record does not provide the primary outcome estimates or the analyses for the listed secondary outcomes. It therefore does not show whether the groups differed, in which direction any difference went, or how precisely any difference was estimated. The absence of posted results should not be interpreted as evidence that the treatments had the same outcome, nor as evidence that one treatment was better.

General explanation: statistical evidence is assessed using an estimate, its uncertainty, the design and analysis choices, and the relevance of the measured outcome. A small or imprecise difference and a precise difference can have different implications, but neither can be evaluated without results. Likewise, a p-value alone would not establish clinical importance; no p-value or confidence interval for the primary comparison is reported.

The endpoint itself spans several distinct cognitive and symptom measures. Because the scales differ and favorable directions are not uniform, a single undifferentiated statement about the ImPACT results would be inadequate even if an overall comparison were available. Component-level estimates and their uncertainty would be needed to understand the pattern across outcomes. Those results are not reported in the registry record.

Accordingly, the record supports a description of the trial design and intended questions, not a conclusion about the efficacy or lack of efficacy of LED therapy. It also does not provide enough information to judge the robustness of an analysis, account for missing measurements, or assess how multiple outcomes were handled. The safety counts are limited to the adverse-event information posted and do not resolve the missing efficacy results.

13. Why This Trial Matters Statistically

This trial is statistically notable because its primary endpoint is described through five composite scores rather than one uniform measure. The scores differ in range and direction: some are interpreted as better when higher, while others are interpreted as better when lower. That makes clear definitions of change, component-level reporting, and an explicit analysis strategy important for interpretable conclusions.

The registry also describes assessments at more than one follow-up time, with earlier assessment possible if symptoms resolved. Repeated measures and variable assessment timing can affect which contrast an analysis estimates. General explanation: a prespecified plan helps distinguish the primary question from secondary or exploratory comparisons and clarifies how repeated observations, early assessments, and missing data are handled. Those details are not reported in the registry record.

The record illustrates why design information alone is not enough to interpret a trial. Randomization and masking classifications describe important features of the intended comparison, but a treatment-effect conclusion also requires outcome estimates, uncertainty, analysis populations, and an account of missing data. Here, the registry records zero analyses and does not provide a primary estimate or confidence interval.

The sample-size-assumptions statement is another reason to distinguish planning from results. It describes illustrative calculations based on an observed effect and specified assumptions, but such calculations are not the trial's observed treatment effect and are not observed power. The registry does not report the trial's own sample-size justification. Planning assumptions cannot replace estimates from the outcome data.

Finally, the safety counts show how denominators and event categories matter. Serious adverse events are recorded as zero in each group, while one other adverse event is recorded in the LED group and none in placebo. These counts offer limited descriptive information, not a complete safety assessment. Together, the missing outcome analyses and limited safety detail make transparent reporting especially important for understanding what the study can support.

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 most important trial-specific limitation of the registry record is the absence of primary and secondary outcome analyses. Although the primary endpoint is defined, the record does not provide component means, changes, between-group estimates, confidence intervals, or p-values. The direction and precision of the primary comparison therefore cannot be evaluated.

The endpoint contains five ImPACT composite scores with different ranges and favorable directions. The record does not specify how those components were handled as a family of outcomes or whether a single summary was planned. It notes that the primary outcome was not reduced to one comparison. As a result, the intended interpretation of a primary result is not fully clear from the posted information.

The registry does not report the statistical model, analysis population, missing-data approach, or treatment of assessments at weeks 3 and 6 and earlier assessments after symptom resolution. It also does not report participant flow by outcome. These omissions limit assessment of whether the available observations adequately represent the randomized groups and how uncertainty should be interpreted.

The intervention descriptions are incomplete in the registry record. The treatment description ends after stating the application locations and the placebo description is also truncated. The record does not provide the remaining procedural detail, so the full treatment and placebo procedures cannot be reconstructed.

For safety, the record gives participant counts for serious and other adverse events but does not report death counts, further detail about the one other event, or a fuller account of event timing and assessment. The absence of reported death counts should not be interpreted as a reported zero. These limits concern the available registry information and do not establish what other documentation may contain.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: LED Therapy for the Treatment of Concussive Brain Injury — NCT02383472.
• Registry record last updated 2018-07-26; status last verified 2018-06.
• Results first posted 2018-06-29.
• 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

NCT02383472 is a completed randomized, parallel-group trial sponsored by Boston Children's Hospital. The registry records enrollment of 53 and quadruple masking; its brief summary describes the study as double blind. The study compared the MedX Health Console model 1100 LED intervention with the MedX Health Console model 1100-placebo in patients with mild traumatic brain injury and persistent cognitive symptoms.

The primary outcome was mean difference in change in ImPACT composite scores from baseline to 6 weeks. The registry also lists secondary D-KEFS and symptom outcomes. It records zero analyses and notes that the primary outcome was not reduced to one comparison. No primary or secondary outcome estimates are reported in the registry record.

Serious adverse events are recorded as 0 in both groups; other adverse events are recorded as 1 in the LED group and 0 in placebo. Death counts are not reported in the registry record. The outcome-analysis population, missing-data methods, multiplicity approach, and statistical analysis plan are also not reported.