Evaluation of the Efficacy of Laser Acupuncture on Uremic Pruritus: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluation of the Efficacy of Laser Acupuncture on Uremic Pruritus (NCT06875115), a randomized na study. The primary outcome is Title: Evaluation of the Efficacy of Laser Acupuncture on Ureimc Pruritus.

2. Clinical Question

3. Trial Design

The registry describes a randomized, double-blind, parallel-group trial, marked as completed. It lists an enrollment of 60 and describes 30 patients assigned to laser acupuncture and 30 assigned to sham laser acupuncture. Allocation is listed as randomized, masking as double, and the model as parallel. The phase is listed as NA.

Treatment was delivered during dialysis sessions. The experimental group received laser acupuncture at Xuehai, Quchi, and Bai Chongwo three times per week for four weeks. The control group received sham laser acupuncture at the same acupoints. The registry describes the experimental device as powered and functional, and the sham device as non-functional and not emitting light. It does not report how random allocation was generated or concealed, who was masked, or whether masking was assessed.

The registry lists a start date of 2024-04-09 and a primary completion date of 2024-05-11. Its status is completed. The primary outcome description specifies measurement at baseline and at week 4 after treatment completion, within a four-week timeframe from enrollment to treatment completion.

The brief summary also says that the 5-D Pruritus Scale and DLQI were used before and after the intervention. However, the registry lists one outcome measure, and the primary outcome result is not reported in the registry record. Details of any additional registered outcome, the analysis population, and the handling of participants who did not complete treatment are not reported. The planned sample-size justification and the statistical analysis plan are also 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: All 60 consented participants completed baseline assessment and proceeded to randomization without exclusions. No participants withdrew or were removed prior to group assignment.

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 Title: Evaluation of the Efficacy of Laser Acupuncture on Ureimc Pruritus, measured over A 4-week timeframe from enrollment to treatment completion..

The primary endpoint is the severity of uremic pruritus measured with the 5-D Itch Scale. The registry describes the instrument as a validated measure covering itch duration, degree, direction, disability, and distribution. Its total score ranges from 5 to 25, with higher scores indicating worse pruritus. Measurements were taken at baseline and at week 4 after the laser acupuncture or sham intervention.

A continuous score preserves gradations in reported symptom severity rather than placing participants into only broad categories. Comparing measurements over time can describe how scores changed during the intervention period. For a randomized comparison, the key question is whether the change in the laser acupuncture group differs from the change in the sham group. That comparison requires the group results and a stated analysis; neither is reported in the registry record.

The brief summary also mentions the DLQI as an assessment before and after intervention. Its role relative to the registered primary outcome, the way it was scored, and any results are not reported in the registry record. The description of the primary endpoint gives the assessment schedule and score interpretation, but not the observed baseline values, week 4 values, treatment contrast, or uncertainty around that contrast.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation depends on both the design and the results. The registry identifies a randomized parallel-group comparison and a continuous primary measure. It does not report the group outcome values or the analysis used to compare them. The concepts below explain how such a comparison is generally interpreted; they do not describe an analysis confirmed for this trial.

What does randomization contribute?

In general, random assignment is intended to create groups that are comparable, on average, at the start of a trial. It reduces the risk that assignment is systematically related to measured or unmeasured participant characteristics. Randomization does not guarantee that every characteristic will be balanced in a particular trial, especially in a modest-sized study. Baseline information and the allocation procedure help readers assess the comparison, but these details are not reported in the registry record.

The registry labels this trial randomized, but the method used to generate the allocation sequence, how assignments were concealed before enrollment, and whether randomization was stratified are not reported in the registry record. These are distinct design features: generating an unpredictable sequence concerns how assignments are determined, while concealment concerns whether the upcoming assignment could be known when a participant enters the trial.

How should a continuous outcome be compared?

For a continuous outcome such as the 5-D Itch Scale, a general approach is to summarize scores within each group and estimate a between-group contrast. Because measurements are described at baseline and week 4, an analysis might compare week 4 scores while accounting for baseline, compare changes from baseline, or use another prespecified model. These approaches can have different assumptions and interpretations. The statistical analysis plan and the specific method used are not reported in the registry record, so no one approach can be attributed to this trial.

A mean is a measure of the center of a set of scores. A standard deviation describes how spread out individual scores are around the mean; it is not the uncertainty in the estimated mean or in the treatment contrast. A standard error or confidence interval is used to describe uncertainty in an estimate. The registry identifies the outcome as a mean with standard deviation, but no observed mean or standard deviation is reported in the registry record.

A treatment contrast should be interpreted with its direction defined. For this scale, higher scores indicate worse pruritus, so a lower score represents less severe reported symptoms. However, the record does not provide values from which to identify the direction or size of any group contrast. No effect estimate can be reconstructed from the stated scale range or trial design alone.

Why does the confidence interval matter?

In general, a confidence interval expresses the statistical uncertainty around an estimated effect under the assumptions of the analysis. It helps distinguish a relatively precise estimate from one that is compatible with a broad range of effects. An interval should be read together with the estimated contrast and the outcome scale. It does not by itself establish that an effect is important to patients, and it does not remove concerns about bias, missing observations, or unsuitable model assumptions.

No confidence interval or treatment estimate is reported in the registry record. Therefore, the precision of the primary comparison cannot be assessed. A statement about statistical significance would also be unsupported: the record does not give a test result or the analysis that generated one.

What can the planning illustration tell readers?

In general, a sample-size calculation asks how many participants per arm would be needed under stated assumptions to detect a chosen effect with a specified level of statistical power and significance. Such a calculation is a planning illustration, not a measure of what the completed study actually observed. A calculation based on an observed effect is especially dependent on that effect estimate and should not be confused with the trial's original design justification.

The registry describes a planning illustration based on the observed effect, with two-sided significance level 0.05, equal allocation between arms, and a normal approximation. It says that the effect to detect is a stated fraction of the observed effect. The calculated participant requirements and the observed effect itself are not reported in the registry record. The record also does not report the trial's own sample-size justification, so the planning assumptions cannot be treated as the protocol's original basis for enrollment.

Such calculations are not observed power. In general, observed power is not a useful substitute for reporting the treatment estimate and its uncertainty: it is tied to the observed result and can obscure how uncertain that result is. Planning illustrations based on different fractions of an observed effect can help show how required enrollment depends on the target effect, but they cannot establish that the estimate is reliable or clinically important. Here, without the observed treatment effect or calculated planning values, no particular sample-size implication can be drawn.

What are the implications of the parallel design?

In a parallel design, participants are assigned to one group and receive that group's intervention rather than crossing over between interventions. The treatment contrast is therefore between groups. The registry describes sham laser acupuncture at the same acupoints as the comparator, which is relevant to the intended comparison of the active and sham procedures. Whether participants, treating staff, or outcome assessors remained unaware of assignment is not reported beyond the registry's double-masking designation. The specific masking roles and an assessment of masking are not reported in the registry record.

In general, analyses should also account for the planned outcome timing and the relationship between repeated measurements from the same participant. The registry describes baseline and week 4 assessment, but it does not say how repeated measurements were handled, whether the analysis followed an intention-to-treat principle, or how missing measurements were addressed. Those choices affect what population and treatment effect an estimate represents.

10. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when several outcomes, time points, subgroup comparisons, or statistical tests are examined. In general, testing many possibilities can increase the chance of a nominally unusual result occurring by chance. Prespecifying a primary outcome and analysis can help readers distinguish the main confirmatory comparison from additional exploratory findings. The registry identifies the 5-D Itch Scale as the primary outcome and gives baseline and week 4 measurement timing. It does not report a multiplicity strategy or a full statistical analysis plan.

The brief summary says the 5-D Pruritus Scale and DLQI were used before and after intervention. The record does not report the role of the DLQI in the outcome hierarchy, whether it was analyzed as a secondary measure, or whether any adjustment for multiple comparisons was planned. The primary result and any DLQI results are not reported in the registry record. The registry also notes that the primary outcome has several categories or time points and is not reduced to one comparison, so a single numerical comparison is not available for interpretation.

Missing-data methods are not reported in the registry record. It is not stated how absent baseline or week 4 measurements were handled, whether participants were analyzed according to their randomized group, or whether sensitivity analyses were conducted. The analysis population and reasons for any missing assessments are also not reported. These details matter because a complete-case comparison can differ from an analysis that includes all randomized participants under a stated model, particularly when missingness is related to symptoms or treatment experience.

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 records zero serious adverse events, zero other adverse events, and zero deaths for both Sham Laser and Laser Acupuncture. The listed figures are counts for the categories recorded; they do not establish that no adverse experiences of any kind occurred. Serious events and other events are distinct registry categories, and a zero count in one category should not be interpreted as a comprehensive description of all possible safety outcomes.

The registry does not report the definitions used for these categories, how events were solicited or verified, the observation period for safety collection, or whether event reporting was complete for every participant. It also does not provide event narratives or a detailed safety analysis. The treatment period is described as four weeks, but the registry does not say whether safety follow-up continued beyond that period.

Counts alone do not quantify uncertainty about uncommon events. In general, an absence of recorded events in a trial does not establish absence of risk, particularly when the available safety information is limited. The figures should therefore be read narrowly as the counts entered in the registry record, not as proof that the treatments were risk-free or that their safety profiles were equivalent.

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

The registry record gives a clear outline of the clinical comparison: laser acupuncture at specified acupoints versus sham laser acupuncture at the same acupoints, administered during dialysis over four weeks. It identifies the 5-D Itch Scale as the primary measure and explains that higher scores indicate worse pruritus. These features help define the intended question and the meaning of the outcome.

They do not, on their own, answer whether the groups differed. The primary outcome result is not reported in the registry record. There are no group scores, change estimates, confidence intervals, or test results available in the trial details. As a result, no conclusion about the direction, size, or precision of a difference between the intervention and comparator can be drawn from this record.

The registry's description of the study as randomized and double-blind concerns the intended design. It does not replace information about implementation, analysis, or results. The specific randomization and masking procedures, the analysis population, missing-data handling, and statistical plan are not reported in the registry record. These omissions limit assessment of how the reported design was carried out and how a treatment estimate would have been obtained.

The safety counts also have a limited interpretation. The record lists zero serious adverse events, zero other adverse events, and zero deaths in each group, but it does not give the safety-monitoring methods or the scope of event collection. Those entries cannot establish that no unwanted events occurred or that the interventions have no risks.

Overall, the record supports a description of the study design, treatment schedule, comparator, and primary measure. It does not support a conclusion about the efficacy or lack of efficacy of laser acupuncture, nor a confident safety comparison. Such conclusions would require outcome estimates, uncertainty measures, and fuller information about conduct and analysis, none of which are reported in the registry record.

13. Why This Trial Matters Statistically

This trial is statistically informative as an example of why design information and outcome information serve different purposes. Randomization, a parallel comparison, a sham procedure, and a stated primary measure define how a treatment contrast was intended to be studied. They do not provide the contrast itself. Without outcome values and an estimate with uncertainty, the central statistical question remains unanswered in the registry record.

The primary measure is continuous and has an explicitly described direction: higher 5-D Itch Scale scores indicate worse pruritus. Clear scale interpretation is necessary for understanding an eventual estimate. A reader would still need the magnitude and precision of the group comparison to judge what the observed data show. Neither is reported in the registry record.

The study also illustrates why a registry's completion status and its outcome reporting should be considered separately. The record is marked completed and gives dates and intervention details, but the primary results are not reported. The safety counts are present, yet important context about collection and definitions is not. A fuller statistical account would ordinarily describe the analysis population, missing-data approach, model, and any plan for handling multiple outcomes or time points; those details are not reported in the registry record.

Finally, planning calculations and observed results answer different questions. The record describes planning assumptions based on an observed effect, but the effect and calculated participant requirements are not reported. Even when available, planning illustrations do not substitute for estimates from the trial or establish that an effect is precise or meaningful. The statistical importance of this record is therefore chiefly in what it specifies about the intended comparison and in identifying the result and methods information needed for interpretation.

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 central limitation for interpretation is that the primary outcome result is not reported in the registry record. No baseline or week 4 group values, treatment contrast, variability estimate, confidence interval, or p-value is given. This prevents assessment of the direction, magnitude, and precision of the primary comparison. The summary mentions the DLQI, but its results and analytic role are not reported either.

Several design and analysis details are also absent. Although allocation is listed as randomized and masking as double, the sequence-generation method, allocation concealment, identities of masked groups, and any assessment of masking are not reported. Eligibility criteria, baseline characteristics, the analysis population, and the statistical model are not reported in the registry record. The handling of missing outcome data, withdrawals, protocol deviations, and repeated measurements is also not described.

The registry does not report the original sample-size justification or a complete statistical analysis plan. It describes a planning illustration based on the observed effect, but the observed effect and calculated planning values are not reported. A multiplicity strategy for outcomes, time points, or any additional analyses is not reported. These omissions make it difficult to assess whether the analysis followed prespecified methods or how robust any result would be to alternative reasonable choices.

Safety reporting is limited to counts of serious events, other events, and deaths. Definitions, ascertainment procedures, follow-up duration for adverse events, and event-level details are not reported. The record also does not state whether the safety figures reflect all randomized participants or a different analysis population. These trial-specific gaps limit interpretation beyond the stated design and recorded counts.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Evaluation of the Efficacy of Laser Acupuncture on Uremic Pruritus — NCT06875115.
• Registry record last updated 2025-12-24; status last verified 2025-11.
• Results first posted 2025-12-24.
• 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 describes a completed, randomized, double-blind, parallel trial of laser acupuncture versus sham laser acupuncture for uremic pruritus. Enrollment is listed as 60, with 30 patients in each group. Treatment was given during dialysis three times per week for four weeks at Xuehai, Quchi, and Bai Chongwo; the sham device was described as non-functional and not emitting light.

The primary outcome is the 5-D Itch Scale, measured at baseline and week 4. Higher scores indicate worse pruritus. The brief summary also mentions the DLQI. The primary outcome results, DLQI results, statistical analysis plan, missing-data methods, and analysis population are not reported in the registry record. The record lists zero serious adverse events, zero other adverse events, and zero deaths in each group; safety-collection details are not reported.