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 Pulsed Dye Laser and Affirm Laser in the Treatment of Abdominoplasty Scars (NCT00735254), a randomized na study. The primary outcome is Efficacy of PDL vs Affirm Laser vs Combined Laser Treatments in Appearance of Surgical Scar.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00735254 |
| Phase | NA |
| Condition | Abdominoplasty Scars |
| Allocation | Randomized |
| Design model | Single Group |
| Masking | Double |
| Enrollment | 3 |
| Arms in the primary outcome | n/a |
| Lead sponsor | The Cleveland Clinic |
| Results posted | Yes |
2. Clinical Question
Population
People with abdominoplasty scars were the intended population. The primary outcome description refers to surgical scars following closure of a transverse abdominal incision.
Intervention
The planned treatments were pulsed dye laser (PDL), Affirm laser, and a combination of PDL and Affirm. The registry describes treatment starting one week after incision closure.
Comparator
The registry lists placebo as another treatment arm. The record does not report how participants were assigned, treated, or followed, and it does not provide results comparing any of the listed arms.
Primary question
The stated question was whether 585-nm PDL, 1440-nm Affirm, or their combination affected the appearance of a surgical scar, with the primary outcome timeframe listed as 1 year. The registry record reports that the study was not conducted per protocol and that data were not collected. It therefore does not answer the treatment-comparison question.
The study title and outcome description focus on scar appearance. The brief summary also describes redness, small visible blood vessels, and scar texture as aspects of appearance that motivated the research. However, the primary outcome record does not specify a scoring instrument, assessor, measurement unit, or a single defined appearance measure. No observed outcome values or arm-level comparisons are reported.
3. Trial Design
The registry describes the study as randomized and double-masked, while classifying its model as single group. It also lists four arms: pulsed dye laser, Affirm laser, combined PDL and Affirm lasers, and placebo. These metadata do not establish how randomization or masking were implemented, or how the listed arms fit the single-group model. Those details are not reported in the registry record.
Enrollment is listed as 3. That is the registry enrollment figure; the record does not report how many participants were assigned to each arm, received treatment, or completed follow-up. The study is marked terminated. Its start is listed as 2008-07 and its primary completion as 2009-07. The primary outcome timeframe is 1 year, but there are no collected outcome data to describe follow-up in practice.
The intended procedures involved PDL, Affirm, their combination, or placebo treatment of a surgical scar. The outcome description says treatment would begin one week after closure of a transverse abdominal incision. The registry does not report treatment schedules, device settings, eligibility criteria beyond the condition entry, or details of the placebo procedure.
The primary outcome is titled as an assessment of efficacy in the appearance of a surgical scar. The record does not provide a prespecified measurement scale or a statistical comparison for that outcome. It reports that the study was not conducted per protocol, data were not collected, and the study was reported to the IRB and closed. Accordingly, the listed design describes the intended study and registry metadata, not a completed comparison with analyzable results.
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
| Stage | Pulsed Dye Laser | Affirm Laser | Combined PDL and Affirm Lasers | Placebo |
|---|---|---|---|---|
| STARTED | 1 | 1 | 1 | 0 |
| COMPLETED | 0 | 0 | 0 | 0 |
| NOT COMPLETED | 1 | 1 | 1 | 0 |
Reasons for not completing this period:
| Reason | Pulsed Dye Laser | Affirm Laser | Combined PDL and Affirm Lasers | Placebo |
|---|---|---|---|---|
| Protocol Violation | 1 | 1 | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: study was not conducted per protocol, data was not collected, study terminated. Reported to IRB and closed 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: PI left institution, no data available.
| Characteristic | Unit | Pulsed Dye Laser | Affirm Laser | Combined PDL and Affirm Lasers | Placebo | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | 0 | 0 | |
| Age, Customized: age >= 18 | — | — | — | — | — | |
| Sex/Gender, Customized: male or female | — | — | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as Efficacy of PDL vs Affirm Laser vs Combined Laser Treatments in Appearance of Surgical Scar, measured over 1 year.
| 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 outcome is titled “Efficacy of PDL vs Affirm Laser vs Combined Laser Treatments in Appearance of Surgical Scar,” and its timeframe is listed as 1 year. Its description identifies treatment with 585-nm pulsed dye laser and 1440-nm Affirm laser for surgical scars, starting one week after closure of a transverse abdominal incision. The brief summary frames the clinical interest around scar appearance, including redness, visible small blood vessels, and texture.
The registry record does not specify how appearance was measured. It gives no scale, unit, assessor, scoring rules, or threshold for a meaningful change. It also does not report a particular primary contrast or outcome value. Without those details, the endpoint cannot be interpreted as a defined numerical measure or connected to a specific statistical effect.
In general, a primary endpoint is the main outcome used to address a study’s central question. A clearly defined measure helps readers understand what was assessed, when it was assessed, and how a treatment contrast should be interpreted. In this record, the endpoint title and description establish the intended topic and timeframe, but not the operational measurement. Most importantly, the outcome population note says the study was not conducted per protocol and that data were not collected. No primary endpoint result is reported.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record does not report an efficacy result. It states that the study was not conducted per protocol, data were not collected, and the study was terminated and closed. Consequently, there is no observed scar-appearance outcome to compare among pulsed dye laser, Affirm laser, combined treatment, and placebo.
Enrollment is listed as 3, but the record does not say how many participants were assigned to each arm or whether any received the planned interventions. The enrollment figure alone cannot establish the size of an analyzed group or support an estimate of treatment effect. There are no arm-level outcome summaries, effect estimates, confidence intervals, or reported significance tests. No analysis records are listed.
The registry lists zero participants at risk and zero affected participants for serious and other adverse events in each of the four groups, as well as zero deaths. These entries must be read alongside the statement that data were not collected. With no reported data collection and no participants listed at risk in the adverse-event entries, the zeros do not establish that no adverse events occurred during treatment. The record provides no event narratives or additional safety results.
In general, an effect estimate describes the observed contrast between groups, while a confidence interval conveys the precision of that estimate and the range of values compatible with the data under the analysis assumptions. Neither is available. A p-value also cannot be interpreted because no outcome analysis is reported. The absence of an analysis is not evidence that the groups were equivalent, nor evidence for or against a treatment effect.
The registry’s randomized and double-masked labels describe intended or registered design characteristics, but they do not substitute for collected outcomes. Likewise, the listed 1-year timeframe is a planned endpoint timeframe, not confirmation that participants were followed for that duration. The record does not support conclusions about comparative efficacy, the size or direction of any effect, or the safety of the interventions. It documents a terminated study without collected outcome data.
9. Statistical Methods Explained
The statistical information available in the registry is limited. The study is labeled randomized and double-masked, and its model is labeled single group. Four treatment arms are listed. The record does not describe the randomization procedure, the masking procedures, the intended group comparisons, or how the single-group model relates to the listed arms. The discrepancy in these design descriptions cannot be resolved from the registry record.
What an effect estimate would describe
In general, an effect estimate for a comparative study summarizes the difference in an outcome between the groups being compared. For this study, that would require a defined scar-appearance measure and collected measurements for the relevant arms. The registry does not identify a specific scoring scale or provide measurements. It therefore supplies no effect estimate, and no unadjusted recalculation can be made from posted summary statistics.
In general, a confidence interval communicates the uncertainty around an estimated effect. Its width depends on the data and the analysis assumptions; a narrow interval indicates greater precision than a wide one. Because the registry reports no outcome data or treatment-effect estimate, there is no confidence interval to interpret. There is also no reported p-value or statistical test result.
What the outcome description establishes
The primary outcome title concerns the appearance of surgical scars, and the timeframe is listed as 1 year. The description names 585-nm PDL and 1440-nm Affirm treatment and says the treatment was to start one week after closure of a transverse abdominal incision. These details identify the intended clinical topic and timing, but the record does not define the measurement itself. The unit, assessment method, scoring schedule, and primary contrast are not reported in the registry record.
In general, endpoint definitions matter because different measures of appearance can capture different features and can use different scales. A numerical score may require a specific analysis appropriate to its scale and distribution. Without the measure and data, readers cannot determine which analysis would have been suitable or reproduce a result.
Randomization, masking, and group structure
In general, randomization is intended to make treatment groups comparable with respect to factors that could affect an outcome, while masking is intended to limit the influence of treatment knowledge on care or assessment. These design labels alone do not show whether the procedures were successfully implemented. Here, the registry does not report allocation details, who was masked, or whether masking was maintained. It also does not report arm-specific participant counts or outcomes.
The registry lists a randomized allocation and double masking but also labels the model single group. It records PDL, Affirm, combined PDL and Affirm, and placebo as arms. Since no protocol-level explanation is available in the record, the precise planned analysis structure is not established. The title of the endpoint names treatment comparisons, but that title does not specify which comparisons were prespecified or how they would be tested.
Planning calculations and observed evidence
In general, sample-size planning uses assumptions about a target effect, variability, significance level, allocation, and analysis method. Such calculations are planning illustrations, not observed evidence and not a measure of the results actually obtained. The registry record does not report a sample-size justification or the assumptions used by the study team. No observed effect is reported. Therefore, any planning illustration based on an observed effect cannot be treated as a study result or as evidence of power in this trial.
In general, over-dispersion occurs when outcome variability exceeds what a chosen statistical model assumes. When present, it can make uncertainty estimates too small if the model does not account for it. The registry provides no outcome distribution, model, or analysis from which over-dispersion or another distributional issue could be assessed. This is a general statistical consideration, not a finding about this study.
There are no analysis records listed. The registry does not report an analysis population, covariate adjustment, missing-data procedure, interim analysis, or statistical plan. With no collected outcome data, none of these analytic choices can be evaluated from posted results. The appropriate interpretation is therefore descriptive: the registry records a planned randomized, double-masked study with four listed arms, but no analyzable efficacy results.
10. Multiplicity, Missing Data and Analysis Populations
The registry record does not report a multiplicity strategy. The endpoint title names PDL, Affirm, and combined laser treatments, and the interventions list placebo, but the record does not specify which pairwise or overall comparisons were planned as primary. Without defined comparisons and outcome results, it is not possible to assess how multiple treatment contrasts or outcome measures would have been handled.
The record lists one outcome measure, but the outcome description does not specify a measurement scale or whether appearance would have been assessed across multiple categories or time points. The record does not report an adjustment for multiple testing, an outcome hierarchy, or a rule for selecting a result among several analyses.
Missing-data methods are not reported in the registry record. The primary outcome population note states that the study was not conducted per protocol and that data were not collected. There are no reported participant flow details, arm-specific counts, or follow-up data from which to distinguish missing measurements from participants who were never assessed.
The analysis population is also not reported in the registry record. There is no stated intention-to-treat, per-protocol, or other analysis set, and no analysis records are listed. These omissions prevent evaluation of how participants would have been handled in an efficacy analysis. They should not be interpreted as evidence that a particular method was or was not used outside the information recorded in the registry.
11. What the Result Does, and Does Not, Mean
The main statistical meaning of this record is that the planned treatment question remains unanswered in the posted results. The registry describes a randomized, double-masked study with PDL, Affirm, combined treatment, and placebo arms, but it also reports termination and no data collection. There is therefore no basis in the record for estimating how scar appearance differed by treatment.
Enrollment is listed as 3, but that figure does not reveal the number treated, the distribution across arms, or the number with follow-up measurements. No outcome summaries, effect estimates, confidence intervals, or tests are reported. This means the record cannot show either the size or direction of a treatment effect, and it cannot show how precise an estimate might have been.
The registry’s adverse-event entries list zeros for participants at risk and affected participants in each group. Given the outcome note that data were not collected, those entries should not be read as evidence that the interventions produced no adverse events. The registry does not provide an evaluable safety comparison.
In general, a missing result is different from a result showing no difference. A study with no collected outcome data cannot establish equivalence or rule out meaningful differences. It also cannot establish that an intervention improves or worsens the measured outcome. The absence of a reported analysis is a limitation of the evidence available in this record, not a numerical finding about treatment.
The intended endpoint concerns scar appearance at 1 year, but the record does not define the measurement instrument or report that follow-up occurred. Thus, the stated timing and treatment aim describe the research question, not observed participant experience or clinical benefit. No medical conclusion about the treatments follows from the posted results.
12. Why This Trial Matters Statistically
This record illustrates an important distinction in clinical-trial interpretation: a registered design is not the same as a set of analyzed results. Randomization and masking are relevant design features, but they do not provide evidence about an outcome when the registry reports that data were not collected. Without outcome measurements, a treatment effect cannot be estimated.
The study is also a reminder that an endpoint needs an operational definition to support statistical interpretation. “Appearance of surgical scar” identifies a broad subject, but the record does not specify a scale, assessor, or scoring method. Such details determine what an outcome value represents and how comparisons should be analyzed. The missing measurement definition is especially consequential when no outcome data are available.
The registry lists multiple treatment approaches and placebo, yet does not explain the relationship between those arms and its single-group model classification. It also does not report the planned comparisons or analysis population. These gaps limit the ability to reconstruct the intended statistical analysis even before considering the lack of results.
The enrollment entry and adverse-event zeros should likewise be interpreted in context. Enrollment does not establish an analyzed sample, and zero entries alongside an explicit statement that data were not collected do not establish a lack of events. Careful reading of trial status and data-collection notes prevents registry metadata from being mistaken for evidence of treatment effects or safety.
For biostatistical interpretation, the central lesson is that no estimate is not a null estimate. This record documents a research question and its termination, but it does not quantify an answer. The distinction protects readers from treating absent data as evidence that groups had similar outcomes.
13. 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 principal limitation is explicit: the outcome population note says that the study was not conducted per protocol, data were not collected, and the study was terminated. As a result, the registry contains no efficacy outcomes to analyze. Enrollment is listed as 3, but arm-specific assignment, treatment receipt, and follow-up counts are not reported.
The design information is incomplete and internally difficult to reconcile. The record labels allocation randomized and masking double, classifies the model as single group, and lists four arms. It does not explain the group structure or provide details of randomization and masking. These fields are insufficient to reconstruct how the study would have been conducted.
The primary outcome is not operationally defined. Although its title and description concern surgical-scar appearance and list a 1-year timeframe, the record gives no measure, unit, assessor, scoring procedure, or prespecified contrast. The record also does not report a statistical analysis plan, sample-size justification, multiplicity approach, missing-data method, or analysis population.
The adverse-event entries list zero participants at risk and zero affected participants in every listed group, while the outcome note states that data were not collected. Those entries cannot support a safety conclusion. The record provides no participant flow or other information that would clarify the status of safety monitoring.
Finally, the registry gives no reported outcome results or analysis records. These limitations mean that neither treatment efficacy nor comparative safety can be evaluated from the posted record. They do not establish what might have been observed had data been collected.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Pulsed Dye Laser and Affirm Laser in the Treatment of Abdominoplasty Scars — NCT00735254.
- Registry record last updated 2018-02-08; status last verified 2018-02.
- Results first posted 2018-02-08.
- 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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Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
17. Record Summary
The registry describes a randomized, double-masked study of PDL, Affirm laser, combined PDL and Affirm, and placebo for abdominoplasty scars. It lists a single-group model, enrollment of 3, and a primary outcome concerning surgical-scar appearance at 1 year. The outcome description refers to 585-nm PDL and 1440-nm Affirm treatment beginning one week after closure of a transverse abdominal incision.
The study is marked terminated. The primary outcome population note says the study was not conducted per protocol, data were not collected, and the study was reported to the IRB and closed. No efficacy analysis or outcome result is reported. The adverse-event entries list zero participants at risk and affected in each group, but do not establish safety in the context of the stated lack of data collection.
The record therefore documents the intended research question and its termination, not a comparative estimate of treatment effects.