Clinical Evaluation of the GLYDe Dressing for Post-surgical Incision Care: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Clinical Evaluation of the GLYDe Dressing for Post-surgical Incision Care (NCT00766727), a randomized na study. The primary outcome is Scar Evaluation at End of Treatment Period Comparing Treated to Standard of Care (Control).

2. Clinical Question

The study description frames the question around whether the dressing might minimize scar formation. The primary outcome is a score assigned to photographs of scars, rather than a direct measurement of scar size or a report of symptoms. The registry describes a 100 point Visual Analog Scale, with a score of 0 indicating a better outcome and a score of 100 indicating a worse outcome. Lay and professional panels evaluated professional photographs taken 12 months postsurgery.

The posted summaries report a mean score of 18.64 for the GLYDe-treated group and 50.52 for the standard-of-care control group. Because higher scores represent worse outcomes under the scale definition, the direction of these means favors lower scores in the treated group descriptively. The registry also reports a mean difference of -31.88 from a Wilcoxon (Mann-Whitney) analysis. However, it does not report a p-value or confidence interval for that analysis. The available record therefore permits a description of the observed scores and their direction, but not a precise assessment of statistical uncertainty or a definitive inferential conclusion.

3. Trial Design

The registry describes a completed study of the GLYDe Dressing for post-surgical incision care. It lists the allocation as randomized and the masking as none. At the same time, it identifies the design model as single group, while listing both GLYDe Dressing and standard of care as arms and reporting a treated-versus-control outcome. The record does not explain this difference between its design classification and the two-group comparison.

Enrollment is listed as 12. The scar outcome summaries each have a group size of 9, whereas the safety results list 12 participants at risk in each group. The registry does not explain how these counts relate to one another, whether they represent different analysis populations, or why the outcome and safety denominators differ. They should therefore be read as distinct counts as posted, rather than reconciled by assumption.

The primary outcome is a continuous score summarized by a mean and standard deviation. The reported timeframe is through 12 months. The description says that professional photographs were taken 12 months postsurgery and evaluated by lay and professional panels. The registry lists one primary outcome measure and one analysis. No secondary outcome measures are posted.

The record lists the study as completed and gives the sponsor as Neodyne Biosciences, Inc. It does not report the study's detailed statistical plan, a sample-size justification, or the procedures used to generate the allocation sequence. It also does not report whether the assessors were blinded to treatment assignment. The listed absence of masking applies to the study design entry; further detail about who knew treatment assignments during photography or scoring is 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

Analysis population for the primary outcome, as defined in the registry: Patient population undergoing elective plastic surgery.

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 Scar Evaluation at End of Treatment Period Comparing Treated to Standard of Care (Control), measured over through 12 months.

The primary endpoint is the evaluation of scars after treatment, comparing GLYDe-treated scars with standard-of-care control scars. It is expressed as a score on a scale and summarized using means and standard deviations. According to the outcome description, professional photographs were taken 12 months postsurgery and assessed by lay and professional panels using a 100 point Visual Analog Scale. Lower scores indicate a better outcome, while higher scores indicate a worse outcome.

A scored photograph provides a structured way to compare the appearance of scars across treatment groups. The use of a defined scale can make judgments more consistent than an unstructured description, while evaluation by both lay and professional panels brings more than one perspective to the assessment. The registry does not report how many people served on either panel, whether the ratings were combined, how disagreements were handled, or whether assessors were blinded to treatment assignment. Those details matter when interpreting a measure that depends on visual ratings.

This endpoint is a measure of scar appearance as rated from photographs. It is not, by itself, a measure of pain, function, quality of life, or other clinical outcomes. The direction of the scale is important: a smaller score represents a better rating. The treated group mean is 18.64, compared with 50.52 for the control group. Those means describe the posted scores, but interpretation of the precision and reliability of the difference is limited because the registry record does not report a confidence interval or a p-value.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the outcome summary describe?

The primary outcome is continuous: each scar receives a score on the Visual Analog Scale. A continuous measure can take values across a scale rather than belonging only to categories such as yes or no. The registry reports group means, which describe the arithmetic average score, together with standard deviations, which describe the spread of scores around each group mean. A mean gives a compact summary of a group, but does not show the distribution of individual ratings, whether scores cluster tightly, or whether a few ratings are unusually high or low.

For this outcome, lower scores are defined as better and higher scores as worse. Thus, a lower mean is directionally more favorable under the registry's scoring definition. The reported treated mean is 18.64 and its standard deviation is 10.86. The control mean is 50.52 and its standard deviation is 15.17. Each group has 9 outcome observations listed. These are descriptive summaries, not measures of the uncertainty in the difference between groups. The standard deviation describes variation among scores; it is not a confidence interval for the mean or the treatment contrast.

What does the named test do?

The registry names the Wilcoxon (Mann-Whitney) method. As a general statistical explanation, this rank-based test compares how observations from two groups are ordered relative to one another. It is often used when a direct model for normally distributed outcomes is not preferred, or when the analysis is framed around distributional ordering rather than only mean values. A rank-based test does not, in general, test only whether two arithmetic means differ. Its interpretation depends on the distributions and on the question being tested.

The registry describes the analysis parameter as a mean difference (final values), and reports -31.88. It does not describe how that mean difference was paired with the Wilcoxon test, nor does it give further methodological detail. The reported number should therefore be attributed to the registry's analysis as labeled, rather than treated as a separately verified estimate. The test's p-value and a confidence interval are not reported in the registry record.

Why does uncertainty matter?

A confidence interval is a range of values compatible with the observed data under a specified statistical procedure and its assumptions. It can communicate both the estimated direction and the precision of a comparison. A narrow interval usually indicates greater precision than a wide interval, although interpretation also depends on the study design and analysis. Here, no confidence limits are reported for the primary analysis, so the precision of the -31.88 estimate cannot be judged from an interval.

A p-value, when reported, describes how compatible the data are with a particular null hypothesis under the test's assumptions. It does not quantify the probability that a treatment works, and it does not measure the size or clinical importance of an effect. No p-value is posted for this analysis. It would be inappropriate to infer one from the means, standard deviations, and group sizes: doing so would require choosing assumptions and a method that are not established by the registry record, and it would not reproduce the named rank-based test.

How should the analysis populations be read?

The registry lists enrollment as 12, while the outcome summaries list 9 participants in each group and the safety entries list 12 at risk in each group. Different denominators can result from different analysis populations or outcome availability, but the reason for the counts in this trial is not reported in the registry record. The numbers should not be combined or reconciled by calculation. Without a reported participant flow, it is not possible to determine how many people were randomized to each group, how many contributed photographs, or why the posted outcome count differs from the safety count.

Missing outcome data can affect a comparison if the people with observed scores differ in relevant ways from those without scores. General statistical practice may address this through prespecified analysis populations, imputation, or sensitivity analyses, depending on the design and missingness. The registry does not report whether any scores were missing, how missing data were handled, or whether sensitivity analyses were conducted. These are unknowns, not evidence that a particular method was or was not used.

What do the planning assumptions mean?

The registry's planning assumptions describe an illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation between groups, and a normal approximation. The intended effect is defined as a stated fraction of the observed effect. Such calculations are planning illustrations: they estimate participant requirements under assumptions and are not observed power. The record does not report the trial's own sample-size justification or design calculation. In addition, the record indicates that values for a two-group continuous-endpoint comparison are missing or not estimable, so no planning participant counts can be interpreted from this entry.

Over-dispersion is a general concern when a statistical model assumes less variability than is present in the data. If variability is understated, standard errors may be too small and intervals may appear more precise than warranted. The posted primary analysis is rank-based, and the record does not report a model-based variance analysis or an over-dispersion assessment. The available summaries do include standard deviations, but they do not establish whether any model assumptions were checked.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("GLYDe Dressing (Treated)", "SoC (Control)")
n   <- c(9, 9)
m   <- c(18.64, 50.52)
sp  <- c(10.86, 15.17)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  GLYDe Dressing (Treated)  9  18.640  10.860  10.292  26.988
CARM  SoC (Control)  9  50.520  15.170  38.859  62.181

11. Analyses Reported by the Sponsor

The registry reports the sponsor's analysis as a Wilcoxon (Mann-Whitney) comparison with a stated mean difference of -31.88 for final values. It does not report a confidence interval or p-value for that analysis. The record also does not provide enough information to reconstruct the named rank-based test from the group means and standard deviations alone. Individual observations, or additional test-specific summaries, would be needed for an independent check of that procedure.

No recalculated two-group result is available for this continuous endpoint. The record notes that values are missing or not estimable for that comparison. Therefore, there is no independent recalculation to compare numerically with the registry's reported result. The posted group means and standard deviations remain useful descriptive statistics, but they cannot substitute for the sponsor's inferential test or establish its precision.

The record does not flag a discrepancy between a posted analysis and a recalculation. The sponsor analysis should be read as the inferential result recorded for the trial, with its limitations in reporting kept in view: the test is named, the contrast is stated, and uncertainty measures are absent. The descriptive direction is consistent with lower, better scores in the treated group, but the available information does not establish the statistical significance or precision of the contrast.

12. Multiplicity, Missing Data and Analysis Populations

The registry lists one primary outcome measure and one analysis, and it lists no secondary outcome measures. This limited set of posted outcomes does not establish whether the full study protocol included other outcomes, analyses, or time points. A multiplicity plan for handling several statistical tests is not reported in the registry record. It is therefore not possible to assess whether any adjustment for multiple comparisons was planned or applied, or whether the posted analysis was selected from a broader set of analyses.

The outcome description refers to photographs evaluated by lay and professional panels. The record does not explain whether the panel scores were analyzed separately, averaged, or combined in another way. It also does not describe any repeated ratings, scoring procedures, or analysis of panel-to-panel agreement. These details could affect the interpretation of the reported score, but they are not available in the registry entry.

Missing-data handling is not reported. The outcome summaries list 9 participants in each group, while enrollment is listed as 12 and the safety entries list 12 at risk in each group. The registry does not describe participant flow, the number with available photographs, the analysis population, or why these denominators differ. It does not state whether outcome values were imputed, whether participants were excluded from the analysis, or whether sensitivity analyses were performed. No conclusion about the amount or handling of missing data can be drawn from the counts alone.

The record identifies the allocation as randomized but does not report an intention-to-treat analysis or another named analysis population. It also classifies the model as single group while listing treated and standard-of-care groups for the outcome. The record does not resolve this difference. These reporting gaps limit the ability to evaluate whether the displayed comparison follows the planned analysis and whether all randomized participants were represented.

13. 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 safety record lists 12 participants at risk in each group. It reports 0 serious adverse events and 0 other adverse events for GLYDe Dressing, and 0 serious adverse events and 0 other adverse events for standard of care. Deaths are listed as 0 in both groups. No serious adverse-event terms are listed.

These figures mean that the registry reports no events in the categories it summarizes among the participants listed at risk. They do not establish that no unwanted effects occurred outside the categories or collection procedures reflected in the record. The registry does not report the safety observation period, how events were collected, or further definitions for the event categories. Nor does it provide enough detail to establish whether the listed safety populations match the outcome-analysis populations.

The safety denominators differ from the outcome group sizes, which are listed as 9 each, and from total enrollment of 12. The record does not explain this. Zero recorded events should therefore be interpreted as a description of the posted safety counts, not as proof that the dressing or standard of care has no risks. The figures also do not support a comparative safety conclusion on their own, particularly without detail about follow-up and event ascertainment.

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

The registry record shows lower average scar-evaluation scores in the GLYDe Dressing group than in the standard-of-care group. Because the scale defines 0 as better and 100 as worse, this is a favorable descriptive direction for the treated group. The reported mean difference is -31.88, and the named analysis is Wilcoxon (Mann-Whitney). These registry entries describe the posted outcome results; they do not by themselves prove that the dressing caused the difference.

The record does not include a p-value or confidence interval. Consequently, the precision of the reported contrast and the strength of statistical evidence cannot be evaluated from the listed analysis. The group means and standard deviations do not tell the full story of the individual score distributions, and the named rank-based test cannot be independently reconstructed from those summary statistics. Clinical importance also cannot be determined from the score difference alone: the registry does not report a threshold for a meaningful difference or additional outcomes that would establish its implications.

Several design and reporting details remain unresolved. Although the record lists randomized allocation, it also labels the model single group while reporting treated and control results. It lists 12 enrolled, 9 in each outcome group, and 12 at risk in each safety group, without explaining the relationships among these counts. The registry does not report how missing scores were handled, whether assessors were blinded, or the sample-size justification. These gaps limit appraisal of the analysis and its generalizability.

The safety entries report no serious or other adverse events and no deaths in the listed groups. Those counts describe what was recorded, but they do not establish the absence of risk. Overall, the record offers a descriptive comparison of scar scores at the stated 12-month timeframe. It does not provide the uncertainty measures or methodological detail needed to make a firm inferential claim about the treatment contrast.

15. Why This Trial Matters Statistically

This trial is statistically interesting because its posted results combine a continuous score, a rank-based test, and a reported mean difference. Those elements answer related but not identical questions. The mean summarizes the average score, while a Wilcoxon (Mann-Whitney) procedure is generally based on rank ordering. Clear reporting of the estimand, test, and uncertainty measure helps readers understand exactly what a result represents. In this record, the analysis is named and the contrast is stated, but the p-value and confidence interval are absent, and the relationship between the test and mean-difference label is not explained.

The entry also illustrates why participant counts need context. Enrollment is listed as 12, the outcome summaries list 9 participants per group, and safety counts list 12 at risk per group. These figures may refer to different populations or stages of follow-up, but the record does not explain them. A transparent participant flow and explicit analysis-population definitions would help readers evaluate how representative the outcome summaries are of the randomized study population.

Finally, the design classification and reported comparison do not align clearly: the registry lists randomized allocation and a single-group model, while reporting a treated-versus-control result. This does not resolve whether the trial was conducted appropriately; it identifies a reporting ambiguity that affects interpretation. The statistical lesson is broader than this study: a favorable descriptive contrast is most informative when accompanied by a clearly defined comparison, analysis population, uncertainty estimates, and a coherent account of design and methods.

16. 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 direct limitation of interpretation is the lack of uncertainty estimates for the primary comparison. The registry reports a contrast but no confidence interval or p-value. The reported means and standard deviations do not provide a substitute for those measures, especially because the named procedure is rank-based and the record does not provide individual scores or further test details.

The registry's design entries are difficult to reconcile. Allocation is listed as randomized, but the design model is single group, while the outcome is reported for treated and standard-of-care groups. The record does not explain this combination. It also does not give details about sequence generation, allocation concealment, assessor masking, or the conduct of the comparison. The entry that masking is none does not clarify whether photographic assessors knew the treatment group.

Counts also require caution. Enrollment is listed as 12, each outcome group is listed with 9 participants, and each safety group lists 12 at risk. The registry does not explain these differences or describe participant flow and analysis populations. Missing-data methods, exclusions, and sensitivity analyses are not reported. It is therefore uncertain how the analyzed outcome groups relate to the enrolled population.

The endpoint is a photograph-based rating of scar appearance. The registry does not describe the number of raters, how panel ratings were combined, or whether scoring reliability was assessed. The record also does not give a clinically meaningful score threshold or other outcomes that would clarify the practical importance of the observed contrast. The trial's own sample-size justification and detailed statistical plan are not reported. These limitations do not negate the posted descriptive results, but they restrict assessment of their precision, robustness, and broader relevance.

17. Related Tutorials

18. Related Statistical Calculators

19. Sources

• ClinicalTrials.gov: Clinical Evaluation of the GLYDe Dressing for Post-surgical Incision Care — NCT00766727.
• Registry record last updated 2020-12-14; status last verified 2020-12.
• Results first posted 2020-12-14.
• 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.

20. Record Summary

The registry describes a completed study of the GLYDe Dressing for post-surgical incision care in people undergoing elective plastic surgery, with the listed condition focused on abdominoplasty incisions. It lists randomized allocation, no masking, and a single-group model, while reporting an outcome comparison between the dressing and standard of care. That design description is not clarified in the record.

The primary outcome is a photograph-based scar score through 12 months, with lower scores defined as better. The posted means are 18.64 for GLYDe Dressing and 50.52 for standard of care; each outcome group lists 9 participants. The reported analysis is Wilcoxon (Mann-Whitney), with a mean difference of -31.88. A p-value and confidence interval are not reported. The record lists 12 enrolled and safety denominators of 12 per group, without explaining how those counts relate to the outcome groups.

The safety summary reports 0 serious adverse events, 0 other adverse events, and 0 deaths in both listed groups. The available record supports a descriptive account of the posted scores and safety counts, but leaves uncertainty, analysis populations, and several design details unresolved.