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 Comparison Study of Wound Closure at Time of Cesarean Delivery: Dermabond Glue Versus Surgical Staples (NCT00524511), a randomized na study. The primary outcome is Wound Complication Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00524511 |
| Phase | NA |
| Condition | Cesarean Section |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 136 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Massachusetts, Worcester |
| Results posted | Yes |
2. Clinical Question
Population
Women having a cesarean delivery and a resulting abdominal skin incision. The registry record lists cesarean section as the condition. It states that no participants were analyzed for the primary outcome because of poor enrollment, loss to follow-up, and incomplete or partial data.
Intervention
Dermabond, a skin-closure glue, applied to close the cesarean skin incision. The intervention description identifies women receiving Dermabond for skin closure.
Comparator
Surgical skin staples, described as the standard skin-closure method in the registry record. The comparison concerns closure of the skin incision, not a comparison of different ways to perform the cesarean delivery itself.
Primary question
Whether the wound-complication rate within six weeks of the study intervention differed between the Dermabond and surgical-staple groups. The endpoint description includes seroma or hematoma, wound separation, a wound requiring packing, cellulitis, and extra medical clinic visits to evaluate the wound. No primary-outcome analysis is reported.
The registry describes a randomized, parallel-group comparison with no masking. It also describes patient surveys about experience and scar appearance, physician feedback about the ease of using Dermabond, and physician assessment of incision appearance after a six-week recovery period. Patient satisfaction of wound cosmesis is named as a secondary outcome. These planned topics do not supply comparative results: the record lists no analyses, and the primary-outcome population is explicitly described as unanalyzed. The available record therefore identifies the clinical question and intended outcomes, but does not resolve the comparison.
3. Trial Design
The trial is titled “Comparison Study of Wound Closure at Time of Cesarean Delivery: Dermabond Glue Versus Surgical Staples.” Its official title describes a comparative study of closure techniques after cesarean section. The registry lists randomized allocation, a parallel model, and no masking. The two interventions are Dermabond and surgical skin staples, with one group assigned to each closure method. The listed phase is NA, and the record identifies the study kind as other.
The registry lists enrollment as 136 and identifies the sponsor as University of Massachusetts, Worcester. The study start is recorded as 2007-09, primary completion as 2012-05, and status as terminated. These are registry entries, not evidence that the planned outcome assessments were completed or analyzed. In particular, the primary-outcome population statement says that no participants were analyzed because of poor enrollment, participants lost to follow-up, and incomplete or partial data. The registry also lists zero analyses.
The brief description says participants would be randomly assigned to skin closure with staples or Dermabond. It describes surveys of patients about their experience and scar appearance, surveys of physicians about ease of use, and physician evaluation of incision appearance after a six-week recovery period. Complications were also to be assessed. The primary outcome is labeled wound complication rate, with a timeframe of within six weeks of the intervention. The record names patient satisfaction of wound cosmesis as a secondary outcome and lists two outcome measures in total, but does not provide analysis results for them.
Details about sequence generation, concealment of allocation, the operational procedure for random assignment, and any departures from the assigned method are not reported in the registry record. The record also does not report the intended analysis population, a protocol-specific statistical plan, or a sample-size justification. Randomized allocation is important to the design, but without analyzed outcome data it cannot by itself establish whether the closure methods differed in this trial.
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: The study design dictates that patients be enrolled upon admission to Labor and Delivery. Subsequently, patients who did not deliver by cesarean delivery would be excluded
Overall Study
| Stage | Group Receiving Alternative Skin Closure Method (Dermabond) | Group Receiving Standard Skin Closure Method (Surgical Staples |
|---|---|---|
| STARTED | 68 | 68 |
| COMPLETED | 64 | 61 |
| NOT COMPLETED | 4 | 7 |
Analysis population for the primary outcome, as defined in the registry: No participants were analyzed due to poor enrollment, subjects lost to follow-up and incomplete/partial data.
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.
| Characteristic | Unit | Group Receiving Alternative Skin Closure Method (Dermabond) | Group Receiving Standard Skin Closure Method (Surgical Staples | Total |
|---|---|---|---|---|
| Participants analysed | 68 | 68 | 136 | |
| Age, Categorical: <=18 years | Participants | 1 | 0 | 1 |
| Age, Categorical: Between 18 and 65 years | Participants | 67 | 68 | 135 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 68 | 68 | 136 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
6. Primary Endpoint
The registry lists the primary outcome as Wound Complication Rate, measured over within six weeks of study intervention.
| 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 endpoint is the wound complication rate within six weeks of the study intervention. The registry description includes wound seroma or hematoma, wound separation, a wound requiring packing, cellulitis, and extra medical clinic visits to evaluate a wound. These events concern healing and the need for further wound assessment or care, rather than cosmetic appearance alone.
As a general statistical concept, a complication endpoint can summarize clinically relevant events in a defined follow-up period. Comparing such an endpoint between randomized groups can help estimate whether outcomes differed under the assigned closure methods, provided that outcome definitions and assessment are applied consistently and that enough outcome information is available. The meaning of a rate also depends on a clear denominator: readers need to know which participants were followed and included, as well as how events were counted.
For this trial, the endpoint’s name, event descriptions, and timeframe are recorded, but the primary-outcome population statement says no participants were analyzed. No event-level outcome results or group comparison for this endpoint are reported in the registry record. Therefore, the endpoint cannot be used to estimate a wound-complication rate for either group from the posted results. Patient satisfaction of wound cosmesis is named separately as a secondary outcome; it should not be treated as a substitute for the primary complication endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical limitation is that the registry record does not report an analyzed primary outcome. It explicitly states that no participants were analyzed because of poor enrollment, loss to follow-up, and incomplete or partial data. The record lists enrollment as 136, but does not give an analyzed denominator for the wound-complication outcome. Without analyzed participants and outcome counts for each closure group, a comparison of complication rates cannot be estimated from the registry results.
The record describes randomized allocation, which is intended to make comparison groups comparable on average at the point of assignment. That design feature does not repair missing outcome information. When follow-up is incomplete, the analyzed participants may differ from those not followed or not included. If the chance of missingness is related to wound outcomes or group assignment, a comparison among those with observed data could be biased. The registry does not report enough information to assess such patterns, and it provides no analysis addressing missing outcomes.
No primary-outcome effect estimate, confidence interval, or p-value is reported. Consequently, the posted results do not establish the direction or magnitude of any difference between Dermabond and staples, and they do not show how precisely such a difference could be estimated. This is not evidence that the methods had equal outcomes; it is an absence of a reported analysis capable of answering the comparison question.
The record’s safety listing reports zero serious adverse events and zero other adverse events among 68 participants at risk in each group. Those counts should be read as the registry’s recorded adverse-event figures, not as a replacement for the missing primary wound-complication analysis. The adverse-event listing does not report deaths, and the registry record does not give a reason for the missing death values. The adverse-event categories and the primary wound-complication endpoint are not interchangeable: the primary description includes specific wound events and extra clinic visits, whereas the safety listing groups events by seriousness.
The trial status is terminated, and the record lists zero analyses. No reason for termination beyond the primary-outcome note about poor enrollment and incomplete data is reported in the registry record. Taken together, the posted information describes the planned comparison and documents that an evaluable primary-outcome comparison is absent. It does not support a conclusion about which closure method had more or fewer wound complications.
9. Statistical Methods Explained
What does random allocation contribute?
As a general statistical principle, random allocation is designed to distribute both measured and unmeasured participant characteristics across comparison groups without systematically favoring one assignment. When outcomes are collected and analyzed as planned, this supports a causal interpretation of the difference between groups, subject to the quality of implementation, follow-up, and measurement. The registry lists this study as randomized and parallel, with Dermabond and surgical staples as the assigned methods. It does not report the sequence-generation method, allocation concealment, or whether assignment was implemented without departures.
Randomization is not a guarantee that all groups will look identical, especially in a trial with limited enrollment. More importantly for this record, randomization cannot replace missing outcome observations. The statement that no participants were analyzed for the primary outcome means that the registry does not provide the data needed to estimate a randomized-group contrast for that endpoint.
What would a group comparison estimate?
As a general concept, a comparison of event rates would use the number of participants meeting the wound-complication definition and the number of participants assessed in each group. A contrast could then describe the difference in observed event frequency between assignment groups. A confidence interval would express the range of effect values compatible with the data under the statistical model; it communicates precision as well as the estimate itself. A p-value, when reported, addresses compatibility between the observed data and a specified null hypothesis under the assumptions of the test. Neither measure can be recovered from a record that reports no analyzed primary outcome and no outcome counts by group.
The endpoint definition matters to this comparison. The registry lists seroma or hematoma, separation, a wound requiring packing, cellulitis, and extra clinic visits to evaluate the wound. Consistent criteria are important because differences in how events are identified or counted can change the apparent group rates. The registry does not report detailed adjudication procedures, whether events were independently reviewed, or how multiple events in one participant would be handled.
What role does the stated planning illustration have?
The registry’s description of a planning illustration specifies 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, and distinguishes participant counts per arm from total event counts for time-to-event settings. These are assumptions for a planning illustration computed from an observed effect; the record explicitly says this is not the trial’s own design. No trial-specific sample-size justification is reported in the registry record.
Planning calculations and trial results answer different questions. A planning calculation estimates what enrollment might be needed under selected assumptions. It is not an observed outcome, does not show that a trial achieved its intended precision, and is not observed power. Because no primary-outcome estimate is reported, a reader cannot use the posted results to judge whether a planning illustration based on an observed effect corresponds to the trial’s actual clinical question or data. No numerical planning result is reported in the registry record.
How should missing outcome data be understood?
As a general concept, missing data reduce the information available for estimating group outcomes. The consequences depend not only on how much information is missing but also on why it is missing and whether missingness is associated with assignment or outcome. An analysis restricted to participants with complete observations can be misleading if those participants differ systematically from those without complete data. Methods such as imputation or sensitivity analysis can explore assumptions about missing outcomes, but the chosen approach and its assumptions need to be reported.
For this trial, poor enrollment, loss to follow-up, and incomplete or partial data are stated as reasons no participants were analyzed for the primary outcome. The registry does not report the number with missing primary outcomes, the timing or pattern of missingness, or any method used to address it. It also does not report an intention-to-treat analysis or another analysis population. Accordingly, there is no basis in the posted results for assessing the effect of missing data on a numerical treatment comparison.
What can be inferred from the absence of analysis?
The registry lists zero analyses. That does not establish that no work of any kind occurred outside the registry; it means the record does not present a reported analysis to interpret. No effect estimate, uncertainty interval, test result, or group-specific primary outcome total is available. Statistical methods can explain what such results would mean, but they cannot fill in the absent trial outcomes. The appropriate interpretation is therefore about the limits of the record, not about a numerical advantage or disadvantage for either closure method.
10. Multiplicity, Missing Data and Analysis Populations
The registry names wound complication rate as the primary outcome and patient satisfaction of wound cosmesis as a secondary outcome. The brief description also refers to patient surveys about experience and scar appearance, physician feedback about ease of use, physician assessment of incision appearance after a six-week recovery period, and complications. The record lists two outcome measures overall, but does not describe how the survey and assessment topics map to those measures or provide results for them.
Multiplicity arises when several outcomes, comparisons, or time points are tested. As a general statistical concept, examining more results can increase the chance of finding an apparently notable result by chance if no adjustment or prespecified hierarchy is used. The registry record does not report a multiplicity strategy, a hierarchy beyond labeling a primary and secondary outcome, or the number of statistical tests planned. It therefore cannot establish whether multiplicity was addressed in an analysis.
Missingness is directly relevant: the primary-outcome statement says no participants were analyzed because of poor enrollment, loss to follow-up, and incomplete or partial data. The record does not report the number of participants with missing information for each outcome, reasons by group, or methods for handling missing data. It also does not report the analysis population or whether all randomized participants were intended to be included in the primary analysis. These omissions prevent evaluation of selection effects, completeness, and robustness to missing data.
The registry lists zero analyses and does not report a statistical analysis plan. A method for controlling multiplicity, handling missing observations, or defining analysis populations is therefore not reported in the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Group Receiving Alternative Skin Closure Method (Dermabond) | 0 | 68 | 0.0% |
| Group Receiving Standard Skin Closure Method (Surgical Staples | 0 | 68 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Group Receiving Alternative Skin Closure Method (Dermabond) | 0 of 68 |
| Group Receiving Standard Skin Closure Method (Surgical Staples | 0 of 68 |
The registry’s adverse-event listing records zero serious adverse events and zero other adverse events in the Dermabond group, with 68 participants at risk. It records the same figures for the surgical-staple group: zero serious adverse events and zero other adverse events, with 68 participants at risk. The death entries are null, so deaths are not reported in the registry record. No serious adverse-event terms are listed.
These figures describe what the registry recorded in its safety fields. They do not establish that no adverse events occurred outside the recorded information, nor do they establish that the primary wound outcomes were absent. A zero count is meaningful only in relation to the completeness of event collection, follow-up, and the population represented by the at-risk count. The record does not explain those processes or resolve the stated problems with enrollment and outcome data.
Safety categories should also be kept distinct from the primary endpoint. The wound-complication definition includes specific wound conditions and additional clinic visits, while the adverse-event listing classifies serious and other adverse events. The safety figures cannot supply the missing group-specific wound-complication analysis, and they do not permit an assessment of comparative safety beyond the recorded counts.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, parallel-group study was designed to compare Dermabond with surgical staples for skin closure at cesarean delivery. It identifies the primary question as a comparison of wound complications within six weeks and names a cosmetic-satisfaction outcome. It also documents that the trial was terminated and that no participants were analyzed for the primary outcome because of poor enrollment, loss to follow-up, and incomplete or partial data.
What the record does not establish is whether wound complications were more frequent with either closure method, whether the methods differed in cosmetic satisfaction, or how precise any comparison might be. No group-specific primary outcome results, effect estimate, confidence interval, or p-value are reported. The absence of a reported analysis should not be interpreted as proof of no difference. Nor does the record support a conclusion that either method is superior, equivalent, or inferior.
The listed adverse-event counts are limited to the registry safety fields and do not fill that evidence gap. They record zero serious and zero other adverse events for 68 participants at risk in each group, while death values are not reported. Those entries are not a substitute for the primary wound-complication outcome, and the record does not explain completeness of safety follow-up.
In general, a randomized comparison can be informative when outcomes are measured and analyzed for the assigned groups. Here, the design description helps identify what the investigators intended to compare, but the absent primary analysis prevents that intended comparison from being estimated. The meaningful statistical conclusion is about the limits of the posted evidence: it describes the research question and its incomplete outcome record, not the comparative effect of the two closure methods.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distinction between a randomized design and an informative result. Random allocation is a strong design feature for comparing assigned strategies, but it only supports an effect estimate when usable outcome information is available. The record’s primary-outcome note says that no participants were analyzed, so the study’s randomized design does not yield a reported comparison of wound complications.
The trial also shows why enrollment, retention, and outcome completeness are part of the evidence, not administrative details separate from the analysis. Poor enrollment, loss to follow-up, and incomplete or partial data are the stated reasons for the absence of a primary analysis. Without group-specific outcome denominators and event counts, readers cannot assess the frequency of complications, estimate a difference, or judge statistical precision.
A further statistical lesson is to distinguish a planning illustration from the trial’s own design and results. The record’s stated planning assumptions include a two-sided significance level of 0.05, equal allocation, and a normal approximation, but it labels the illustration as based on an observed effect rather than the trial’s design. Such assumptions do not establish that the trial was adequately planned, completed, or analyzed. The registry does not report a trial-specific sample-size justification.
Finally, the safety listing and the primary endpoint answer different questions. Zero recorded adverse events in the safety fields cannot be used as evidence about the unreported wound-complication comparison. Keeping outcome definitions, analysis populations, and missingness distinct is essential to avoid drawing conclusions the registry results cannot 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 consequential limitation is that the registry reports no analyzed participants for the primary outcome. It attributes this to poor enrollment, participants lost to follow-up, and incomplete or partial data. The record lists enrollment as 136, but does not give the number randomized, the number followed, or the analyzed denominator for the primary endpoint. The listed at-risk counts in the adverse-event fields do not establish the primary-outcome analysis population.
The registry does not report group-specific wound-complication counts, outcome rates, effect estimates, confidence intervals, or p-values. It therefore offers no basis for evaluating the size, direction, or precision of a primary-outcome difference. It also does not report results for the named cosmetic-satisfaction outcome or the other assessments described in the brief summary.
Details needed to appraise conduct and analysis are not reported in the registry record. These include the method for generating and concealing assignments, the intended primary analysis population, the handling of missing data, procedures for outcome assessment, and any statistical analysis plan. The record does not report a trial-specific sample-size justification, interim analyses, or a multiplicity strategy.
The trial is listed as terminated, but a reason beyond the primary-outcome note is not reported in the registry record. The safety fields record zero serious and zero other adverse events for 68 participants at risk in each group, but do not explain the completeness or duration of safety ascertainment. These limitations mean the record is useful for identifying the intended comparison and the reason an outcome analysis is unavailable, but not for estimating comparative outcomes.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Comparison Study of Wound Closure at Time of Cesarean Delivery: Dermabond Glue Versus Surgical Staples — NCT00524511.
- Registry record last updated 2013-03-05; status last verified 2013-01.
- Results first posted 2013-03-05.
- 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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18. Record Summary
NCT00524511 is a randomized, parallel-group comparison of Dermabond glue and surgical staples for skin closure at cesarean delivery. The registry lists no masking, enrollment of 136, and status as terminated. The study start is recorded as 2007-09 and primary completion as 2012-05; the sponsor is University of Massachusetts, Worcester.
The primary outcome is wound complication rate within six weeks, with the listed definition including several wound conditions and extra clinic visits to evaluate a wound. Patient satisfaction of wound cosmesis is named as a secondary outcome. The registry states that no participants were analyzed for the primary outcome because of poor enrollment, loss to follow-up, and incomplete or partial data, and it lists zero analyses.
The adverse-event fields record zero serious and zero other adverse events for 68 participants at risk in each group. Death values are not reported. No comparative primary-outcome result is available in the registry record.