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 Rejuvenation of the Lower Eyelid Using a Combination of Two Hyaluronic Acid Fillers - a Pilot Study (NCT00852241), a na phase 4 study. The primary outcome is The Primary Objective of This Study is to Determine the Efficacy and Longevity of the Use of Restylane® and Perlane® in Combination for the Rejuvenation of the Infraorbital Hollows and to Measure Patient Satisfaction With This Treatment.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00852241 |
| Phase | Phase 4 |
| Condition | Infraorbital Hollows |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 18 |
| Arms in the primary outcome | n/a |
| Lead sponsor | The Cleveland Clinic |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned people with infraorbital hollows. The registry record lists 18 participants enrolled, but does not report further eligibility criteria or describe the participants’ characteristics.
Intervention
The intended treatment combined Restylane and Perlane. The arm description specifies one 1.0cc syringe of each filler for both tear trough areas in total.
Comparator
There was no separate comparator group. The study is recorded as a single-group study, with allocation listed as not applicable. It therefore does not provide a like-for-like comparison with another treatment or with no treatment.
Primary question
The stated objective was to assess the efficacy and longevity of the combined fillers for rejuvenation of infraorbital hollows and to measure patient satisfaction. The primary outcome timeframe is listed as 1 year, but the registry record says no data are available because the principal investigator left the institution.
The clinical question is therefore descriptive and exploratory: what outcomes and satisfaction were observed after the combined treatment, and how long were any changes maintained? The registry record does not answer those questions with outcome results. It identifies the intended treatment and objective, but does not give an operational definition of efficacy, a satisfaction measure, or a reported assessment result. Without a control group, even a reported change would not by itself separate the treatment’s contribution from other influences, such as natural variation or expectations. The record supports describing the study’s aim and design, but not drawing a comparative conclusion about the fillers.
3. Trial Design
This is a completed Phase 4 pilot study sponsored by The Cleveland Clinic. The registry record lists a single-group model, no masking, and allocation as not applicable. Enrollment was 18. The study began in 2009-02 and its primary completion was recorded as 2009-09. Its condition is infraorbital hollows.
The intervention group is described as Restalyne and Perlane. The regimen description states that one syringe of Perlane (1.0cc) and one syringe of Restylane (1.0cc) were intended for use across both tear trough areas. The registry lists the interventions as drugs. It does not describe a second group receiving a different treatment or a control condition.
The study’s stated aim was to determine the efficacy and longevity of the combination for rejuvenating infraorbital hollows and to measure patient satisfaction. The primary outcome timeframe is listed as 1 year. However, the record does not describe the outcome instrument, the assessment schedule within that timeframe, or the criteria for judging efficacy or longevity. It also does not report outcome data: the primary outcome description says that the principal investigator left the institution and no data are available.
Because this is a single-group study, its design can describe outcomes among participants who received the regimen if such outcomes are recorded, but it cannot supply a concurrent randomized treatment contrast. The absence of masking also means the record does not indicate that participants or study personnel were unaware of treatment. The registry record does not report further details about enrollment procedures, follow-up completion, or how analyses were to be conducted.
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 | Restalyne and Perlane |
|---|---|
| STARTED | 18 |
| COMPLETED | 0 |
| NOT COMPLETED | 18 |
Reasons for not completing this period:
| Reason | Restalyne and Perlane |
|---|---|
| Physician Decision | 18 |
Analysis population for the primary outcome, as defined in the registry: The Principle Investigator left the institution and no data is available.
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: The Principal Investigator left the institution and no data is available.
| Characteristic | Unit | Restalyne and Perlane |
|---|---|---|
| Participants analysed | 18 | |
| Age, Customized: 18-70 years | Participants | 0 |
| Sex/Gender, Customized: female | Participants | 0 |
6. Primary Endpoint
The registry lists the primary outcome as The Primary Objective of This Study is to Determine the Efficacy and Longevity of the Use of Restylane® and Perlane® in Combination for the Rejuvenation of the Infraorbital Hollows and to Measure Patient Satisfaction With This Treatment, 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 objective combines several ideas: efficacy, longevity of any effect, and patient satisfaction after Restylane and Perlane were used together for infraorbital hollows. The registry lists a primary timeframe of 1 year. It does not specify a measurement scale, a definition of improvement, a threshold for a meaningful change, or how longevity and satisfaction were to be assessed. Consequently, the objective is stated, but the endpoint cannot be reconstructed as a precise statistical outcome from the registry record.
In general, a prespecified endpoint translates a research question into an observable measure. A clear endpoint helps readers understand what was measured, when it was measured, and how an analysis relates to the stated objective. A defined time horizon is also important when the question concerns durability: repeated assessments or a clearly specified event can distinguish persistence from a short-lived change. The 1 year timeframe identifies a period of interest, but does not, on its own, explain the measurement or analysis.
The registry record reports that no primary outcome data are available because the principal investigator left the institution. Thus, there is no posted endpoint result to interpret, and the efficacy, longevity, and satisfaction objectives remain unanswered by the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that the registry record contains no primary outcome data. Although it states a primary objective and a 1 year timeframe, it does not report an efficacy estimate, a measure of longevity, or a patient satisfaction result. There is therefore no observed primary result from which to assess the direction, size, or precision of an outcome. The lack of a reported result is not evidence that the intervention had no effect; it means that the registry record does not make the outcome available for evaluation.
The study enrolled 18 participants in a single group. This describes the registered enrollment, not necessarily the number with completed follow-up or usable primary outcome data. The record does not report how many participants contributed outcome measurements, whether follow-up was complete, or how any missing observations were handled. Those details matter because the information available for analysis may differ from the enrollment count.
The single-group design also limits what could be inferred even if outcome changes were reported. A before-and-after difference within a group can describe observed change over time, but without a concurrent comparator it cannot isolate the contribution of the intervention from other possible influences. Since no primary results are posted, even that descriptive assessment cannot be made from this record.
The safety record lists 18 participants at risk for serious adverse events and 0 affected. It also lists 18 at risk for other adverse events and 0 affected, with 0 deaths. These entries are counts in the registry record. They should not be interpreted as proof that no adverse events occurred in every context: the record does not provide detail about ascertainment, follow-up completeness, or the collection and reporting process. Nor do zero reported events establish the absence of risk.
No primary analyses are listed, and the registry record does not report an effect estimate, confidence interval, or hypothesis test for the primary objective. Precision cannot be evaluated without an outcome estimate and its uncertainty. The available information therefore supports a description of the design, registered objective, enrollment, and recorded safety counts, but not a conclusion about efficacy, durability, satisfaction, or comparative performance.
9. Statistical Methods Explained
The registry record identifies a single-group study with no masking and allocation listed as not applicable. It does not report a statistical analysis plan. In particular, the choice of outcome summary, model, handling of repeated measurements, missing-data method, or inferential procedure is not reported in the registry record. No specific method should therefore be attributed to the investigators.
What a single-group result can describe
General statistical context: a single-group study can summarize measurements collected from its participants. If measurements are taken at more than one time, an analysis might describe within-participant change or the distribution of outcomes at specified times. The meaning of such a summary depends on what was measured, when it was measured, and which participants contributed data. The registry record does not give those details for this study, and it does not post primary outcome values.
General statistical context: a within-group change is not the same as a treatment-versus-control effect. Without a comparator, changes over time can reflect factors other than the intervention, including natural fluctuation, measurement variation, or participants’ expectations. A statistical test of change, if one had been performed, would not remove that design limitation. No such test is reported.
Effect estimates and uncertainty
General statistical context: an effect estimate describes the observed magnitude and direction of an outcome according to a chosen scale. A confidence interval describes uncertainty around an estimate under the assumptions of the statistical method. Its width depends on the data and analysis, and the interval is not a guarantee that the true value lies within its limits. An estimate and its uncertainty are needed to judge how precisely the observed data address a research question.
For this study, no primary effect estimate or confidence interval is reported. The outcome measure itself is not described in sufficient detail to identify a scale or a contrast. As a result, there is no basis for interpreting statistical significance, clinical importance, or precision for the primary objective. A missing analysis result cannot be replaced by a conclusion drawn from the study’s title, objective, or enrollment count.
Planning illustrations and observed evidence
The registry record includes assumptions for planning illustrations: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of an observed effect. These are planning assumptions, not a description of the actual single-group design. The record does not report a primary observed effect from which such an illustration could be grounded in posted results. Any planning value based on an observed effect is not an observed trial result and is not observed power.
General statistical context: planning calculations can explore the amount of information a hypothetical study might need under chosen assumptions. They depend on the assumed effect and design, and do not establish that a completed study had adequate power or that an effect was present. A hypothetical two-arm allocation does not turn this registered single-group study into a randomized comparison. Since the primary outcome is unavailable, the planning assumptions cannot remedy the lack of an observed outcome estimate.
What is and is not documented
The record lists one primary outcome measure, but gives no unit, parameter, dispersion, or description of how the outcome was defined. It lists no analyses. The analysis population is not reported in the registry record, and it is not stated whether all enrolled participants were followed or included in any outcome assessment. No adjustment strategy, covariate set, or approach to repeated observations is reported. These are unknowns rather than evidence that a particular method was or was not used in practice.
General statistical context: statistical methods are interpretable only when they are connected to a defined outcome, a defined analysis population, and a transparent account of the data included. Reporting the number analyzed and the way incomplete observations were handled helps readers assess possible bias and precision. For this trial, the record’s statement that no data are available makes those evaluations impossible from the posted results.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one primary outcome measure, but its description is blank and no primary analysis is reported. It does not give a statistical analysis plan or say whether additional outcomes, time points, or subgroup analyses were planned. A multiplicity strategy—such as how error rates would be managed across several formal tests—is not reported in the registry record. It is therefore not possible to determine whether the analysis involved multiple comparisons or how they would have been addressed.
The primary outcome description states that the principal investigator left the institution and no data are available. This is a direct limitation on interpretation: the registry provides no primary outcome result to assess. It does not explain whether data were never collected, could not be located, were incomplete, or were unavailable for another reason. Those circumstances should not be inferred from the statement.
The registry record does not describe participant-level missingness, follow-up completion, exclusions, or an analysis population. It does not say whether the intended analysis would include all enrolled participants, only those with a particular set of observations, or another group. Nor does it report an imputation method, sensitivity analysis, or other approach to missing outcomes. These items are not reported in the registry record.
General statistical context: missing outcome data can affect both the estimated result and its uncertainty, particularly when the reasons for missingness are connected to participants’ outcomes. Transparent reporting of follow-up and the analysis population helps readers judge that possibility. In the absence of outcome data and these methodological details, no assessment of missing-data bias or multiplicity can be made. The central limitation is not simply that an analysis detail is unclear; the primary result itself is unavailable.
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 |
|---|---|---|---|
| Restalyne and Perlane | 0 | 18 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Restalyne and Perlane | 0 of 18 |
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 |
|---|---|
| Restalyne and Perlane | 0 of 18 |
The registry record lists 18 participants at risk for serious adverse events, with 0 affected. It also lists 18 at risk for other adverse events, with 0 affected, and reports 0 deaths. These are the posted counts for the single group, Restalyne and Perlane.
These figures describe what the registry record reports; they do not establish that the treatment is free of risk. The record does not provide event terms, definitions, severity detail beyond the serious-event category, timing, or information about the completeness of safety follow-up. It also does not explain the process used to collect and verify adverse-event information. The absence of listed serious-event terms is consistent with the count of 0 serious events affected, but does not add detail about the broader safety record.
General statistical context: zero events in a study group are still an observation from a limited amount of follow-up, not proof that the underlying event risk is zero. Safety interpretation depends on how many participants were observed, for how long, and how completely events were captured. The registry record does not provide enough information to evaluate those aspects beyond the listed at-risk counts. These counts should therefore be read as registry-reported figures, not as a definitive characterization of safety.
12. What the Result Does, and Does Not, Mean
The record establishes that a completed pilot study was registered to examine a combination of Restylane and Perlane for infraorbital hollows. Its stated interests were efficacy, longevity, and patient satisfaction, with a primary timeframe of 1 year. It also describes a single treatment group and records enrollment of 18 participants. These registry entries explain what the study set out to investigate and the broad design used.
The record does not establish what outcomes participants experienced. The primary outcome description says that no data are available because the principal investigator left the institution. There is no posted efficacy estimate, longevity result, or patient satisfaction result to interpret. This absence cannot be recast as a finding of benefit, no benefit, or no change.
The design also does not support a controlled comparison. A single-group study can potentially describe outcomes among its participants, but it cannot provide a direct randomized contrast against another intervention or a control condition. Even if a within-group change had been posted, it would not by itself establish that the fillers caused the change. In this record, no such primary change is reported.
The safety counts indicate 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths among the listed at-risk group of 18. They should be interpreted as reported counts with limited supporting detail, not as evidence that risk is absent.
Overall, the registry record documents the study’s objective, regimen, design, enrollment, timeframe, and safety entries, while leaving the primary clinical questions unanswered. It cannot establish efficacy, durability, satisfaction, comparative performance, or a complete safety profile. The absence of reported outcome data is a limitation of the evidence available in the record, not a result about how the intervention performed.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of the difference between a registered objective and an interpretable result. The objective names efficacy, longevity, and patient satisfaction, but a research question becomes assessable only when the outcome is defined and results are reported. The registry record gives a timeframe of 1 year, yet provides no outcome data, measurement definition, or primary analysis. Readers cannot assess effect size or precision from an objective alone.
The single-group design is also important. It can be suitable for describing outcomes in a pilot setting, but it does not create a controlled estimate of comparative effect. A change within a treated group and a difference between treatment groups answer different questions. The record has no second group, and the primary result is unavailable, so neither a comparative estimate nor a descriptive primary outcome can be evaluated.
The entry also illustrates why enrollment and safety counts should not be confused with outcome evidence. The record lists 18 enrolled participants and zero affected in the reported adverse-event categories, but those counts do not substitute for an efficacy result or clarify the degree of follow-up and event ascertainment.
Finally, the planning assumptions describe a hypothetical two-arm design and a significance level of 0.05, while the registered study is single-group and has no posted observed primary effect. Planning illustrations can be useful for considering future research, but cannot recover missing trial results or support claims about observed power. The statistical significance of this record lies in making the distinction between intention, design, reported data, and evidence explicit.
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 trial-specific limitation is that no primary outcome data are available. The record attributes this to the principal investigator leaving the institution. It does not provide a primary result for efficacy, longevity, or patient satisfaction, so these objectives cannot be evaluated from the posted results.
The primary outcome is not operationally defined. Although the timeframe is listed as 1 year, the record does not identify the instrument, scoring method, response definition, timing of individual assessments, or method for evaluating durability. The unit, parameter, and dispersion are also absent. This prevents readers from knowing precisely what would count as an outcome or how a result would be summarized.
The study is single-group and unmasked, with no comparator listed. As a result, it cannot provide a controlled comparison, and any descriptive changes—if they were available—would have important interpretive limits. The record does not report eligibility criteria beyond the condition, participant characteristics, recruitment details, follow-up completion, or the analysis population. These omissions restrict assessment of who was studied and how broadly any result might apply.
No analyses are reported. The registry record does not describe an analysis plan, methods for repeated measurements, handling of missing data, multiplicity, or sensitivity analyses. The safety entries also lack detail on event terms, ascertainment, and follow-up. These limitations do not establish that any particular procedure was omitted in practice; they mark information that is not reported in the registry record. Taken together, they prevent evaluation of the primary objective and constrain interpretation of the registered safety counts.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Rejuvenation of the Lower Eyelid Using a Combination of Two Hyaluronic Acid Fillers - a Pilot Study — NCT00852241.
- Registry record last updated 2018-03-12; status last verified 2018-02.
- Results first posted 2018-03-12.
- 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
NCT00852241 is a completed Phase 4 pilot study sponsored by The Cleveland Clinic. It enrolled 18 participants with infraorbital hollows and is recorded as a single-group, unmasked study with allocation not applicable. The intervention description specifies Restylane and Perlane used together for both tear trough areas, with one 1.0cc syringe of each filler.
The study began in 2009-02, with primary completion recorded as 2009-09. Its stated objective was to assess efficacy and longevity and measure patient satisfaction; the primary timeframe was 1 year. The registry record says no primary outcome data are available because the principal investigator left the institution. No analyses are listed.
Safety entries list 0 serious adverse events, 0 other adverse events, and 0 deaths among 18 at risk. These counts do not replace the missing primary outcome or establish the absence of risk. Overall, the record documents the study’s aim and design but does not provide results that answer its primary questions.