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 DDAVP in the Reduction of Post-operative Ecchymosis in Rhinoplasty (NCT01982760), a randomized phase 2 study. The primary outcome is Reduction in Ecchymosis and Swelling.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01982760 |
| Phase | Phase 2 |
| Condition | Postoperative Ecchymosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 14 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University Hospitals Cleveland Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
The registry describes participants undergoing cosmetic rhinoplasty and identifies postoperative ecchymosis as the condition of interest. Its summary says that people with heart, lung, kidney, or liver problems were not eligible. The record lists enrollment as 14, but the primary outcome population is marked “No data collected.” It does not report participant characteristics or a more detailed analysis population.
Intervention
The intervention was DDAVP administered before the operation. The arm description specifies intravenous administration at .3mcg per kg over 30 minutes prior to the operation. The study summary describes DDAVP as desmopressin acetate and says it is used in patients with bleeding disorders.
Comparator
The comparison group was assigned no DDAVP before rhinoplasty. The registry describes a randomized, parallel-group study, but does not report further details about allocation procedures or the number assigned to each arm.
Primary question
The primary question was whether DDAVP was associated with less postoperative ecchymosis and swelling. The registry describes photographs taken preoperatively, at 1 day, and at 8 days post-operatively for assessment of bruising. It does not report collected outcome values, a scoring method, or a statistical comparison. Therefore, the record does not answer whether the groups differed.
3. Trial Design
This was a Phase 2, randomized, triple-masked, parallel-group trial of DDAVP before rhinoplasty. Its registered title identifies the purpose as reducing postoperative ecchymosis. One arm received DDAVP before the operation; the comparator arm received no DDAVP. The registry lists enrollment as 14. It does not give the number allocated to each arm, the allocation sequence method, or details about who was masked. The word “triple” identifies the registered masking level, but the identities of the masked groups or roles are not reported in the registry record.
The study summary describes cosmetic nose surgery and photographs used to evaluate bruising and swelling. The registered primary outcome is titled “Reduction in Ecchymosis and Swelling,” with a timeframe from surgery to 8 days post-operatively. The outcome description mentions photographs before surgery and at 1 day and 8 days post-operatively, analyzed for bruising. This description does not explain how swelling was assessed or how either feature was converted into an outcome measure.
The registry lists a start date of 2013-12, primary completion on 2015-06-25, and status as terminated. The reason for termination is not reported in the registry record. The record includes “Patient Behavior Factors” as a secondary outcome, lists 2 outcome measures, and reports 0 analyses. It does not provide participant flow, arm-specific outcome data, or an account of which analyses were completed.
The design can establish a randomized comparison in principle, but the registered details alone do not show whether allocation, masking, or follow-up proceeded as planned. No protocol details beyond those recorded are available in the registry entry.
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 | DDAVP | No DDAVP |
|---|---|---|
| STARTED | 14 | 0 |
| COMPLETED | 13 | 0 |
| NOT COMPLETED | 1 | 0 |
Reasons for not completing this period:
| Reason | DDAVP | No DDAVP |
|---|---|---|
| Physician Decision | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: No data collected
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: No patients were enrolled in the control arm as the study was terminated.
| Characteristic | Unit | DDAVP | No DDAVP | Total |
|---|---|---|---|---|
| Participants analysed | 14 | 0 | 14 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 14 | 0 | 14 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 9 | 0 | 9 |
| Sex: Female, Male: Male | Participants | 5 | 0 | 5 |
6. Primary Endpoint
The registry lists the primary outcome as Reduction in Ecchymosis and Swelling, measured over surgery to 8 days post-operatively.
| 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 titled “Reduction in Ecchymosis and Swelling.” Ecchymosis refers to bruising, the visible discoloration that can follow surgery. The registry says photographs taken preoperatively and at 1 day and 8 days post-operatively would be analyzed for bruising; the stated timeframe runs from surgery to 8 days post-operatively. The study summary also mentions photographs being evaluated for swelling. A photographic assessment can provide a way to compare visible postoperative changes across assigned groups, provided the scoring approach and assessment conditions are specified and applied consistently.
The registry record does not state a unit, parameter, dispersion measure, or scoring scale. It does not describe who rated the photographs, whether ratings were blinded, how bruising and swelling were combined or handled as separate outcomes, or what change would count as a reduction. The endpoint description thus gives the general subject and observation times, but not enough detail to reconstruct a quantitative outcome.
Most importantly, the primary outcome population is marked “No data collected.” No endpoint values or group comparison are reported. The intended photographic assessment therefore cannot be interpreted as an observed treatment result. Without collected measurements and a defined analysis, the record cannot quantify the extent or precision of any difference in bruising or swelling.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized comparison of DDAVP before rhinoplasty with no DDAVP. However, it reports “No data collected” for the primary outcome population and 0 analyses. It therefore offers no observed estimate of the difference in ecchymosis or swelling between the groups. There is no reported effect size, confidence interval, or significance test to interpret. The trial’s title and objective express the question being studied; they are not evidence of an outcome.
The record lists enrollment as 14, but that figure cannot substitute for analyzed outcome data. It does not say how many participants were allocated to each arm, whether all enrolled participants received their assigned intervention, or whether any participants had photographs assessed. The allocation balance and analysis population are not reported in the registry record. No conclusion about the direction, size, or precision of a group difference follows from enrollment alone.
The registry labels the trial terminated. It does not report why it ended or whether termination affected outcome collection. The status should therefore be read as a description of the study record, not as an explanation for the absence of results. Nor does the absence of a reported result establish that there was no difference; it means the registry entry does not provide the data needed to assess one.
The registered primary outcome brings together ecchymosis and swelling in its title, while its description specifies photographic analysis for bruising. This leaves uncertainty about whether the intended assessment was one combined measure or separate measures, and how swelling would be evaluated. The observation times are described, but there is no reported scale, summary statistic, or comparison method.
The registry also lists adverse-event fields for DDAVP and no-DDAVP groups with zero values for the at-risk and affected counts. These entries do not supply a detailed account of event ascertainment or the context for those zeros. They should not be treated as a substitute for a complete safety analysis.
Overall, the available record documents the planned comparison and some design features, but not its primary results. Any numerical planning illustration based on an observed effect cannot be interpreted as evidence from this trial when the registry reports no collected primary outcome data. No claim that DDAVP reduced, increased, or had no effect on postoperative bruising or swelling is supported by the posted results.
9. Statistical Methods Explained
The registry gives several design labels but does not report a detailed statistical analysis plan. The distinction matters: design labels describe how a trial was organized, while an analysis plan specifies how outcomes are measured and compared. The latter is not reported in the registry record.
What does randomization contribute?
In general, randomization assigns participants to study groups using a chance-based procedure. If implemented as intended, it can reduce systematic differences between groups at the outset, so that a comparison is less affected by known or unknown baseline characteristics. Random assignment does not guarantee that groups will be alike in a small trial, and it does not by itself resolve missing outcomes or measurement problems. The registry identifies the study as randomized but does not describe the allocation sequence, concealment, or group assignment counts. Those details cannot be assessed from the record.
What does masking mean for this outcome?
In general, masking can reduce the influence of expectations on care, participant reports, or outcome assessment. This is relevant when photographs are used to judge visible bruising or swelling, because assessments may involve judgment unless a clearly defined measurement method is used. The record labels the trial triple-masked, but does not identify which roles were masked or describe how photographic ratings were performed. It also does not provide the scoring rules needed to evaluate whether assessment was standardized.
Why do the outcome definition and time points matter?
A statistical comparison requires an outcome that can be measured consistently. For a photographic endpoint, this ordinarily means explaining what is rated, how ratings are recorded, who performs them, and how ratings from different times are compared. These are general methodological considerations, not details confirmed for this trial. The registry identifies preoperative photographs and photographs at 1 day and 8 days post-operatively, but gives no rating scale, unit, or endpoint calculation. It also does not make clear whether ecchymosis and swelling are combined or assessed separately.
Measurements at more than one time can be analyzed in different ways. In general, an analysis might compare groups at a selected time, compare changes from baseline, or model repeated measurements while accounting for their relationship within a participant. These approaches answer related but not identical questions. No analysis choice is reported, and the record does not give outcome values from which any approach could be reconstructed.
What can a confidence interval tell a reader?
In general, a confidence interval expresses uncertainty around an estimated effect under the assumptions of the statistical method. A narrower interval indicates greater precision than a wider interval, while an interval spanning effects in different directions may leave the direction uncertain. A confidence interval is not a guarantee that the true effect lies within its limits. No estimate or confidence interval for the primary outcome is reported in this registry record, so precision cannot be assessed.
How should significance testing be understood?
In general, a significance test evaluates how compatible observed data are with a specified null model, under assumptions of the test. A p-value does not describe the size or practical importance of an effect, and it cannot replace an estimate with an uncertainty interval. The registry reports 0 analyses and no primary outcome data. It therefore provides no test statistic or p-value for the registered primary question. A statistical plan, including a planned test, is not reported in the registry record.
What do the planning assumptions mean?
The registry’s sample-size assumptions describe a planning illustration based on the observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The stated effect to detect is a specified fraction of the observed effect. In general, such calculations estimate the number of participants per arm for a chosen power under the assumed effect and model; they are not evidence that the trial actually had that power. For time-to-event calculations, the record says the tables give total events, while other calculations give participants per arm.
These are planning assumptions, not a reported design justification. The registry does not report a sample-size rationale for the trial, and it does not report primary outcome data from which a trial-specific observed effect could be interpreted. Planning values based on an observed effect should not be confused with an observed treatment result. They also should not be described as observed power. The registry does not report whether any interim analyses were planned or conducted, or whether the stated assumptions were used in the original design.
Finally, over-dispersion is a general concern when outcome variation is greater than assumed by a statistical model; if ignored, uncertainty can be understated. This concept is relevant to some count or rating outcomes, but the registry does not specify the endpoint’s data type or a model for it. There is therefore no basis for saying whether over-dispersion arose or how it was handled in this trial.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists “Patient Behavior Factors” as a secondary outcome and reports 2 outcome measures. The primary outcome title includes ecchymosis and swelling, and its description refers to photographic assessments before surgery and at 1 day and 8 days post-operatively. The record’s note says the primary outcome has several categories or time points and was not reduced to one comparison. Thus, the registered information does not identify a single numerical contrast that captures the primary question.
In general, testing several outcomes, time points, or contrasts increases the chance of obtaining a nominally unusual result by chance if each is tested separately. A prespecified primary contrast and a stated multiplicity approach help clarify which result is confirmatory and how uncertainty is interpreted. No multiplicity adjustment or hierarchy of tests is reported in the registry record. Because no analyses or primary outcome data are reported, there are no test results from which to assess multiplicity in practice.
Missing-data methods are also not reported. The primary outcome population is marked “No data collected,” so the central issue is not a reported rate of incomplete measurements but the absence of collected primary data in the registry entry. The record does not describe participant-level missingness, reasons for unavailable photographs, or any imputation or sensitivity analysis.
The analysis populations are not defined. In general, an intention-to-treat analysis follows participants in the groups to which they were assigned, while other analysis populations may apply different eligibility or treatment rules. The registry does not say which population was planned or analyzed. It lists enrollment as 14, but does not provide participant flow or arm-specific analysis counts. Consequently, neither the handling of deviations nor the population used for any comparison can be determined.
11. What the Result Does, and Does Not, Mean
The trial asks a clinically focused statistical question: whether DDAVP before rhinoplasty is associated with less postoperative bruising or swelling than no DDAVP. The registry records randomization, masking, the two treatment conditions, and planned photographic assessment. These details describe a comparison that could address the question if outcomes were collected and analyzed as specified.
The posted results do not report primary outcome data. The endpoint population is marked “No data collected,” and the registry reports 0 analyses. As a result, there is no reported effect estimate and no measure of its uncertainty. The available record cannot show whether the groups differed, how large any difference might have been, or whether an estimate would be precise.
This absence of results is not equivalent to a finding of no effect. It also does not demonstrate benefit or harm. A registered aim, a treatment mechanism described in the study summary, and a planning illustration are not substitutes for comparative outcome data. The terminated status does not explain why data are absent, because the reason for termination is not reported in the registry record.
The adverse-event fields list zero at-risk and affected counts for both registered groups. Without a fuller account of ascertainment and context, those entries do not establish that adverse events were systematically assessed or that none occurred. They are limited registry entries rather than a detailed safety analysis.
Accordingly, the defensible interpretation is narrow: the registry describes the planned trial question and design, but does not provide results capable of answering the primary question. This interpretation concerns what the record reports, not what may or may not have occurred outside the registry entry.
12. Why This Trial Matters Statistically
This trial is statistically notable because its registry identifies a randomized and triple-masked comparison but supplies no primary outcome data or analyses. That distinction is useful for readers: a design can be described in detail at a broad level while still leaving the principal comparative question unanswered in the results record.
Photographic assessment of bruising and swelling raises measurement questions that are important in many clinical studies. The observation times are identified, but a reader also needs the scoring definition, the assessment process, and a clear description of how outcomes are combined or compared. Without those elements, it is difficult to know what a numerical treatment effect would represent. Those details are not reported in the registry record.
The entry also illustrates why time points and outcome categories need a prespecified analysis strategy. Multiple possible comparisons can make results harder to interpret unless the primary contrast and handling of multiplicity are clear. Here, the record notes several categories or time points but does not report a selected comparison or analysis plan. No result is available to resolve that ambiguity.
Finally, planning calculations and trial findings answer different questions. A planning illustration expresses assumptions about a future or intended comparison; an outcome analysis estimates what the collected data show. The registry states planning assumptions but reports no primary data or analyses. Keeping those roles distinct prevents planning figures from being mistaken for evidence about DDAVP’s effect in this trial.
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 chief trial-specific limitation is that the registry reports no collected primary outcome data and 0 analyses. This prevents estimation of the treatment contrast and its precision. The registry status is terminated, but the reason is not reported in the registry record, so the relationship between termination and outcome availability cannot be established.
The enrolled population and analysis population are insufficiently described for interpretation. The registry lists enrollment as 14 but does not give arm-specific allocation, participant flow, baseline characteristics, or the number with endpoint assessments. The listed exclusion of people with heart, lung, kidney, or liver problems appears in the study summary, but further eligibility criteria are not reported.
The endpoint description is incomplete for reproducible analysis. It names ecchymosis and swelling, specifies photographic assessments before surgery and at 1 day and 8 days post-operatively, and gives a timeframe through 8 days post-operatively. It does not specify a measurement scale, rating procedure, assessor details, or the statistical contrast. The description emphasizes bruising but does not explain how swelling would be quantified.
Other limitations concern reporting. The masking label is not accompanied by information about which roles were masked. The statistical analysis plan, sample-size justification, missing-data methods, multiplicity strategy, and interim-analysis information are not reported in the registry record. The adverse-event entries list zero at-risk and affected counts in both groups, but do not provide further context about ascertainment. These gaps limit what can be inferred from the registry entry, regardless of the intended study design.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: DDAVP in the Reduction of Post-operative Ecchymosis in Rhinoplasty — NCT01982760.
- Registry record last updated 2023-08-16; status last verified 2023-07.
- Results first posted 2023-08-16.
- 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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17. Record Summary
The registry describes a Phase 2, randomized, triple-masked, parallel-group trial of DDAVP before rhinoplasty compared with no DDAVP. The DDAVP arm description specifies intravenous administration at .3mcg per kg over 30 minutes prior to the operation. The primary outcome concerns ecchymosis and swelling assessed using photographs, with observations described before surgery and at 1 day and 8 days post-operatively.
The record lists enrollment as 14, a start date of 2013-12, primary completion on 2015-06-25, and terminated status. It lists “Patient Behavior Factors” as a secondary outcome, 2 outcome measures, and 0 analyses. The primary outcome population is marked “No data collected.” The reason for termination and the primary outcome results are not reported in the registry record.
As a result, the registry entry establishes the planned comparison but does not provide evidence about the size, direction, or precision of any difference in postoperative bruising or swelling.