Effect of Combined Red and Near Infrared Light-emitting Diode (LED) Therapy on Tissue Regeneration Post Laser Treatment: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect of Combined Red and Near Infrared Light-emitting Diode (LED) Therapy on Tissue Regeneration Post Laser Treatment (NCT04834817), a randomized na study. The primary outcome is Days to Healing.

2. Clinical Question

3. Trial Design

This was a randomized, parallel-group study with no masking recorded. The registry lists enrollment of 25 and describes two groups: LED treatment with the Celluma POD device after a laser test area, and control with no treatment after the laser test area. The study status is completed. The recorded start date is 2021-04-01, and the primary completion date is 2024-03-30. The phase is listed as NA.

The primary endpoint description says healing was to be assessed clinically by blinded assessment. That statement concerns the planned assessment of the endpoint; it does not change the registry’s separate designation of the study as unmasked. The record does not explain who was blinded, how the assessment was kept blinded, or whether blinding was maintained throughout follow-up. These details are not reported in the registry record.

The primary outcome was assessed from Day 0 to Day 55, up to 56 days. Pain Level is listed as a secondary outcome. Although the record lists two outcome measures, it does not provide outcome-level results or a description of the analysis population. The record also lists zero analyses, so no statistical comparison is available to interpret.

The adverse-event entries list 25 participants at risk in each group, while the overall enrollment is 25. The registry record does not explain how those group denominators relate to the enrollment figure. This discrepancy in the recorded accounting should be kept in mind when reading the safety counts; it does not permit a reconstruction of group sizes or participant flow.

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.

Population: 32 subjects were screened and consented. 7 subjects were unable to participate due to scheduling difficulties. They never participated in any study procedures. 25 subjects participated in the study as both experimental and control groups.

6. Primary Endpoint

The registry lists the primary outcome as Days to Healing, measured over Assessed from Day 0 to Day 55, up to 56 days.

The primary endpoint is titled “Days to Healing.” Its description defines the intended measure as time and days until complete healing of the treatment sites, with clinical grading by blinded assessment. The stated assessment period was from Day 0 to Day 55, up to 56 days. This kind of endpoint is intended to capture how quickly healing occurs, rather than only whether healing has occurred at a single fixed visit. In general, timing can matter because participants may reach an event at different points during follow-up.

There is an important ambiguity in the registry’s representation of this endpoint. The result type is described as a number of participants, and the outcome classification describes participants with an event as counts. The registry also flags the primary outcome as having several categories or time points and not reduced to one comparison. No outcome values, category definitions, or analysis are reported in the registry record. As a result, the exact form of the intended primary comparison cannot be determined from the posted information.

Without the number of participants who healed, their recorded healing times, or an effect estimate, the endpoint cannot show whether the groups differed or how precisely any difference was estimated. The endpoint description identifies what the study intended to assess, but it is not itself evidence of an observed result.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies the study as randomized and parallel-group. In general, random allocation is intended to make the groups comparable at the start with respect to measured and unmeasured characteristics, apart from chance variation. A parallel-group design assigns participants to a group that receives the intervention or to a group receiving the comparator. These design labels describe the intended structure; they do not show whether the groups were balanced in practice, and the record does not report baseline characteristics or participant flow.

What the endpoint would require

In general, a time-to-event endpoint records how long it takes for a defined event to occur. For this study, the event described is complete healing of a treatment site, with assessment from Day 0 to Day 55, up to 56 days. Such an analysis needs a clear event definition and information about when each event occurred. It also needs a way to account for participants whose event is not observed within the assessment period. The registry record does not provide individual or grouped healing times, a stated censoring approach, or a statistical method for this endpoint.

There is a mismatch between the endpoint wording and the way the outcome is classified in the record. “Days to Healing” suggests a time measure, while the result type is expressed as a number of participants and the classification describes participant event counts. The record further notes multiple categories or time points and does not reduce the primary outcome to a single comparison. Without the result categories and an analysis description, it is not possible to determine which statistical method would be appropriate or how the intended primary result should be read.

Estimates and uncertainty

In general, an effect estimate describes the observed contrast between groups on a chosen scale. A confidence interval describes the range of values compatible with the data and the statistical method, and indicates how precisely the effect has been estimated. Neither is reported for the primary endpoint in the registry record. A p-value, which assesses how compatible data are with a specified null hypothesis under a statistical model, is also not reported. No conclusion about statistical evidence or precision can be drawn without these results.

The registry record lists zero analyses. This means no analysis results are listed in the record; it does not identify a particular model, adjustment strategy, or analysis population. Whether the investigators used an intention-to-treat approach, a per-protocol approach, or another population definition is not reported in the registry record. Nor are missing-data methods, baseline adjustments, or a plan for handling multiple outcome categories reported.

Multiplicity and planning calculations

In general, multiplicity arises when several outcomes, time points, or comparisons are tested. If multiple tests are interpreted without a plan for controlling the chance of false-positive findings, the overall interpretation may be less straightforward. The record flags multiple categories or time points for the primary outcome, but it does not report how these were handled statistically. No multiplicity adjustment or hierarchy of tests is reported in the registry record.

The record describes a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect. No calculated planning values or fractions are included in the registry record for this analysis. In general, sample-size calculations are design illustrations dependent on assumptions; they are not observed power and cannot replace an analysis of trial outcomes. Because the primary result itself is not reported, the planning description cannot establish the precision or strength of the study’s findings.

Finally, the sample-size assumptions state that time-to-event tables use a total event count, while other cases use participants per arm. That general convention does not resolve the endpoint’s representation in this record. A time-to-healing endpoint and a participant-count classification would need a clearly specified analysis and corresponding result for a meaningful statistical interpretation. Those details are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry identifies the primary outcome as having several categories or time points and indicates that it was not reduced to one comparison. It does not name the categories, state which time point or comparison was primary, or describe an adjustment for multiple testing. The record therefore does not establish how the investigators intended to interpret multiple comparisons or control the risk of chance findings across them.

Missing-data handling is not reported in the registry record. In general, incomplete follow-up can affect a healing endpoint if the timing or occurrence of healing is unknown for some participants. The record does not report the number of participants assessed at each time point, withdrawals, losses to follow-up, or a method for handling incomplete outcome data. It also does not specify whether the primary analysis was based on all randomized participants or a narrower analysis population.

The record lists zero analyses and provides no primary or secondary outcome results. It does not report an intention-to-treat population, a per-protocol population, exclusions from analysis, or methods for adjusting for missing data. Pain Level is listed as a secondary outcome, but its results and any multiplicity approach are not reported. Without these details, readers cannot assess whether missingness or multiple outcomes influenced the reported findings; in this case, the findings themselves are not available 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.

The adverse-event entries list zero serious adverse events, zero other adverse events, and zero deaths for the LED Treatment group, with 25 participants at risk. The Control group likewise lists zero serious adverse events, zero other adverse events, and zero deaths, with 25 participants at risk. The registry lists no top serious-event terms.

These figures describe what was entered in the registry; they do not by themselves establish that no adverse events occurred outside the recorded categories or observation process. The record does not report the duration of safety follow-up, definitions used for event collection, completeness of reporting, or a statistical comparison between groups. It also lists overall enrollment of 25, which does not match the group-specific at-risk denominators as presented. The registry record does not explain that relationship. The safety counts should therefore be read as posted counts with unresolved denominator context, not as a comprehensive assessment of safety.

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

The registry record establishes that a randomized, parallel-group study was conducted to assess LED treatment with the Celluma POD device after a laser test area, compared with no treatment. Its primary endpoint was described as time and days to complete healing, assessed from Day 0 to Day 55, up to 56 days. The record also identifies Pain Level as a secondary outcome and lists adverse-event counts.

What the record does not establish is whether the groups differed in healing, how large any difference was, or how precisely it was estimated. Primary and secondary outcome results are not reported in the registry record. No effect estimate, confidence interval, or p-value is available, and the primary endpoint is flagged as involving several categories or time points without a single comparison. Completion status is not a substitute for posted results.

The adverse-event entries show zero recorded events in the listed categories for both groups, using the at-risk denominators shown in the record. Those counts do not demonstrate equivalence in safety, and they do not resolve the inconsistency between overall enrollment and group denominators. The record also does not describe safety follow-up or the completeness of event collection.

In general, a trial’s design and endpoint description explain what researchers intended to compare; evidence about the observed comparison requires outcome data and an appropriate analysis. Since those results and methods are not reported, the findings cannot be used to state that the device changes healing or that it does not. The available information supports a description of the study design and recorded safety counts, but not a conclusion about comparative effectiveness or a definitive safety profile.

13. Why This Trial Matters Statistically

This study illustrates why a clearly named endpoint is not enough for statistical interpretation. “Days to Healing” and the description of time to complete healing imply a timing question, while the registry classifies the result as participant counts and notes several categories or time points. Without the categories, outcome values, and analysis method, the intended comparison remains difficult to reconstruct.

It also highlights the distinction between design information and results. Randomization, a parallel-group model, an unmasked designation, and planned blinded clinical grading describe features of the study. They do not show the observed healing outcomes. The registry record lists the study as completed but does not report an analysis or outcome estimates. A reader therefore cannot assess effect magnitude or precision from the design labels alone.

The safety entries raise a separate reporting issue: the registry lists enrollment of 25 and at-risk denominators of 25 in each group, without explaining how those figures relate. This does not invalidate the posted event counts, but it limits interpretation of the denominator context.

Statistically, this is a useful example of why outcome definitions, analysis populations, follow-up, missing-data handling, multiplicity plans, and numerical results all matter. When these details are absent, restraint is essential: the record can describe what was planned and what counts were entered, but it cannot support a treatment-effect estimate or a conclusion about the primary question.

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 specific study is that the registry record does not report primary outcome values or analyses. Although the endpoint description concerns time and days to complete healing, the record provides no healing times, event counts by group, comparative estimate, confidence interval, or p-value. It also flags several categories or time points without specifying them or giving a single comparison. The effect and its precision cannot therefore be assessed.

The endpoint’s representation is unclear: the title and description refer to time to healing, whereas the result type and classification refer to participant counts. The statistical method used to handle the endpoint is not reported in the registry record. The record does not describe outcome categories, censoring, missing data, the analysis population, participant flow, or multiplicity handling.

The study is designated unmasked, while the endpoint description says clinical grading was to be performed by blinded assessment. The record does not explain the assessor’s role or the procedures used to maintain blinding. It also provides no baseline characteristics with which to evaluate the enrolled groups.

Finally, the registry reports enrollment of 25 but lists 25 participants at risk in each group for adverse events, without explaining the relationship between these denominators. The safety entries lack information about follow-up duration and completeness. These reporting gaps limit both outcome and safety interpretation; they do not justify assumptions about unreported trial procedures or results.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Effect of Combined Red and Near Infrared Light-emitting Diode (LED) Therapy on Tissue Regeneration Post Laser Treatment — NCT04834817.
• Registry record last updated 2025-04-13; status last verified 2025-04.
• Results first posted 2025-04-13.
• 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

NCT04834817 is listed as a completed, randomized, parallel-group, unmasked study sponsored by the University of California, Irvine. Enrollment is recorded as 25. The study compared Celluma POD LED treatment after a laser test area with no treatment after a laser test area. Its primary endpoint was “Days to Healing,” described as time and days to complete healing, assessed from Day 0 to Day 55, up to 56 days. Pain Level is listed as a secondary outcome.

The registry record does not report primary or secondary outcome results and lists zero analyses. It flags the primary outcome as involving several categories or time points, without a single comparison. Serious adverse events, other adverse events, and deaths are listed as zero in both groups, with 25 at risk per group; the relationship to overall enrollment is not explained. The record gives no further information about analysis methods, missing data, or safety follow-up.