Emervel for the Correction of Lower Face Wrinkles & Folds: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Emervel for the Correction of Lower Face Wrinkles & Folds (NCT02718040), a na phase 4 study. The primary outcome is Number of Subjects With Naturalness of Expression in Motion (2D Video).

2. Clinical Question

3. Trial Design

This was a completed Phase 4, multicenter study of Emervel Classic and/or Emervel Deep for correction of lower-face wrinkles and folds. The registry record describes a single-group model, with 30 subjects enrolled. It lists allocation as not applicable and masking as none. Thus, the study does not provide a randomized comparison with an untreated or alternative-treatment group.

The arm description says eligible subjects received bilateral treatment of nasolabial folds and marionette lines. The record does not report how subjects were assigned between the two product types, whether all subjects received both types, or the amount used. It also does not report further details about sites, eligibility criteria, or the study's conduct beyond its listed outcomes.

The recorded study start was 2016-04, and primary completion was 2016-07. The overall status is completed. These dates describe the registry record and do not establish the duration of follow-up for every outcome. The primary outcome has a specified timeframe of 42 days.

The study objectives cover judgments of facial-expression naturalness, perceived attractiveness and age, aesthetic improvement, satisfaction, wrinkle severity, dynamic facial strain, and adverse events. Assessments include treating-investigator judgments, subject reports, photographs, 2D video, and 3D digital photogrammetric analysis. The registry record does not report a detailed statistical analysis plan, a sample-size justification for the study, or how missing measurements were handled.

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

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Number of Subjects With Naturalness of Expression in Motion (2D Video), measured over 42 days.

The primary endpoint is the number of subjects with naturalness of expression in motion at 42 days. Its definition concerns the proportion of subjects whose lower-face expression naturalness was at least maintained—meaning maintained or enhanced—according to the treating investigator's assessment of 2D video. This is a participant-level outcome: each subject is classified according to whether the defined condition is met.

Assessing expression in motion addresses a different aspect of facial appearance from a photograph taken at rest. The endpoint is intended to capture the treating investigator's judgment of whether expression appears natural during movement after treatment. As a general statistical point, a participant count can be interpreted alongside the number assessed to understand how common the outcome was in the analyzed group. The registry record does not report either the observed primary-outcome count or the number assessed for this endpoint, so its proportion cannot be evaluated from the reported information.

The endpoint is assessed at a specified follow-up time, 42 days. That timing gives the outcome a defined reference point, but does not show whether a similar assessment was made at other times or how any repeated assessments were analyzed. Those details are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins with the outcome definition, the population assessed, and the type of comparison the design permits. Here, the primary outcome is a participant count for a binary classification: the treating investigator judged expression naturalness to be maintained or enhanced, or the definition was not met. The registry record names the outcome and assessment method, but does not report the primary result or the number assessed. This prevents estimation of the observed outcome proportion from the recorded information.

What does a participant count represent?

For a binary outcome, the count is meaningful in relation to its denominator: the number of participants whose outcome status was assessed. A proportion expresses the count relative to that denominator. In a single-group study, this describes the observed frequency in the analyzed group; it does not by itself compare treatment with an alternative. The enrolled group size is not necessarily the denominator for every outcome, because some participants may lack an assessment. The registry record does not report the primary-outcome denominator or missingness.

A confidence interval is a general statistical tool for expressing uncertainty around an estimate. For a proportion, it reflects that the observed frequency is an estimate based on the participants assessed, rather than a perfectly precise description of all possible observations in a broader population. A confidence interval for the primary outcome is not reported in the registry record. Without the endpoint count and denominator, the estimate and its precision cannot be reconstructed from the recorded details.

What can a single-group design estimate?

A single-group design can describe outcomes observed among the treated participants, provided the outcome data and analysis are reported. It lacks a concurrent control group for estimating how those outcomes compare with what would have happened under another condition. Changes from baseline, if measured, are not automatically treatment effects. General sources of uncertainty in an uncontrolled comparison include natural change over time, measurement variability, and expectations affecting assessments. The registry record lists masking as none and does not report a control group, so a randomized contrast is not available.

The primary assessment uses 2D video and a treating-investigator judgment. In general, an assessment based on video can capture expression in motion, while a photograph records appearance in a still image. These modalities address different aspects of appearance and are not interchangeable. The registry record specifies the primary assessment modality but does not report further information about rating procedures, assessor training, or reliability.

How should repeated outcomes and multiple measures be viewed?

The study lists 10 outcome measures and includes several related concepts, such as naturalness, attractiveness, age appearance, improvement, satisfaction, wrinkle severity, and dynamic facial strain. When multiple outcomes are assessed, the chance of observing an apparently notable finding among them can be affected by how many comparisons are made and by the analysis choices. This is a general multiplicity concern. The registry record does not report a multiplicity adjustment, a prespecified hierarchy among secondary outcomes, or the detailed statistical plan. It also lists 0 analyses, and does not report results for the secondary outcomes.

Outcomes with different measurement types require different summaries. A participant count or proportion describes a binary classification. A mean change in dynamic facial strain describes a continuous measurement, although its reported result and analysis are not available in the registry record. General methods for continuous data may summarize a central value and variability; the appropriate method depends on the data distribution and study plan. The record does not report how the dynamic strain measure was analyzed.

What do planning calculations mean?

A sample-size calculation is a planning exercise based on assumptions about the effect to detect, variability, allocation, significance level, and desired power. The stated planning illustration is based on a fraction of the observed effect, uses a two-sided significance level of 0.05, assumes equal allocation between two arms, and uses a normal approximation. It is not the trial's own design justification. Because this study is single-group, the equal-allocation, two-arm assumptions do not describe its design. Planning illustrations are not observed power and should not be interpreted as evidence about the probability that this completed study detected an effect.

The registry record does not report the original sample-size justification, the actual primary-outcome analysis, or a statistical model for the study. Accordingly, no conclusion about the adequacy of the analysis or the precision of the primary estimate can be drawn from the available record. If a recalculated result differs from the sponsor's own analysis, the sponsor's own analysis takes precedence; the primary result needed for such a comparison is not reported in the registry record.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Emervel Treatment Group")
n      <- c(30)
events <- c(30)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Emervel Treatment Group  30  30  100.0  88.4  100.0  88.6  100.0  88.8  99.9

11. Multiplicity, Missing Data and Analysis Populations

The study has 10 listed outcome measures spanning investigator ratings, subject reports, image assessments, and facial-strain measurement. Multiple outcomes can raise a general multiplicity issue: if many hypotheses are evaluated, interpretation depends on which outcomes were prespecified as primary, how secondary outcomes were treated, and whether any adjustment was planned. The registry record identifies a primary outcome and lists secondary outcomes, but does not report a multiplicity strategy, a testing hierarchy, or detailed analysis methods. It also lists 0 analyses. Results for the secondary outcomes are not reported in the registry record.

Missing data are another concern because the enrolled group size does not establish the denominator for each outcome. The registry record does not report the number assessed for the primary outcome, the amount or reasons for missing data, or the method used to handle missing assessments. It does not state whether analyses used all enrolled subjects, only those assessed, or another analysis population. Those analysis-population definitions are not reported in the registry record.

Without outcome denominators and missing-data methods, readers cannot determine whether the reported enrolled group corresponds to the population used for each outcome, or assess how incomplete follow-up may have affected the estimates. This uncertainty is separate from multiplicity: both can affect interpretation, but neither can be resolved from the registry information available.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

The adverse-event figures list 30 subjects at risk for serious events and 30 at risk for other adverse events. The recorded counts are 0 serious adverse events, 0 other adverse events, and 0 deaths. The registry record does not list serious-event terms.

These figures describe the recorded experience in the Emervel Treatment Group. They are counts, not comparative estimates: the study has no listed control group, so the figures cannot establish a difference in risk relative to another treatment or to no treatment. A zero count in a study also does not establish that an event is impossible. In general, safety estimates depend on the number assessed, follow-up, and completeness of event reporting. The registry record provides the at-risk figures but does not report further detail about event ascertainment or follow-up for safety.

The safety entries should also be kept distinct from the efficacy outcomes. The absence of recorded adverse-event counts does not provide information about the primary naturalness-of-expression outcome, whose result is not reported in the registry record. Nor does the safety information address outcomes that were not recorded or reported in the registry fields.

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

The study record defines a focused question about treating-investigator judgments of naturalness of lower-face expression in motion at 42 days after treatment. It also documents a single-group design, an enrollment of 30 subjects, and assessments addressing several aesthetic and safety concepts. These details describe the study's scope and structure.

The record does not report the primary-outcome count or proportion, and it does not report results for the listed secondary outcomes. Therefore, the available information cannot establish how often naturalness was maintained or enhanced, how large any observed change was, or how precisely an estimate was measured. The stated endpoint definition is not itself a finding.

The lack of a concurrent comparator also limits causal interpretation. Even if an outcome change were reported, a single-group result would describe observations in that group and would not by itself distinguish treatment effects from other possible influences. The unmasked assessment is an additional consideration when interpreting investigator judgments; the registry record does not report procedures that would quantify or address potential rating effects.

The safety record lists 0 serious adverse events, 0 other adverse events, and 0 deaths in the group at risk. These recorded counts are useful descriptive information, but do not establish comparative safety or rule out events beyond the study observations. They should not be used to infer the unreported efficacy outcomes.

Overall, the registry record supports a description of the design, endpoint definition, enrollment, and recorded safety counts. It does not support a conclusion about the primary outcome's observed frequency or its precision. The study-specific analysis plan, missing-data handling, outcome denominators, and results for the listed secondary measures are not reported in the registry record.

14. Why This Trial Matters Statistically

This study illustrates why a clearly named endpoint is not enough to interpret a trial result. The primary outcome specifies the construct of interest—naturalness of lower-face expression in motion—and identifies the assessment method and follow-up time. But interpretation also requires the observed count and the denominator assessed. Those primary-result details are not reported in the registry record, so the central outcome cannot be quantified from the recorded information.

The single-group design also makes the distinction between description and comparison especially important. A study can record outcomes after treatment without estimating a treatment-versus-control effect. The registry record's classification as single group, with allocation not applicable and masking none, sets limits on causal claims independently of the endpoint definition.

The study also lists outcomes measured through different sources and modalities, including investigator assessments, subject reports, photographs, 2D video, and 3D digital photogrammetric analysis. Such measures can address related but distinct aspects of appearance. Their interpretation depends on the outcome definitions, analysis methods, and reporting of results. The record lists 10 outcome measures but does not report the secondary findings or a multiplicity strategy.

Finally, the safety counts show how descriptive event reporting differs from comparative evidence. Zero recorded events in the listed fields is a study observation, not a guarantee of no risk. Taken together, these features make the record useful for understanding the study question and design while leaving its principal efficacy result and statistical precision unresolved.

15. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most direct limitation for interpretation is that the registry record does not report the observed primary-outcome count, proportion, or denominator. It therefore does not permit assessment of the primary result's magnitude or precision. Although the outcome timeframe is specified as 42 days, the record does not provide primary-outcome findings at that time.

The study is single group and lists no masking. Without a concurrent comparator, observed outcomes cannot be separated from other possible influences through a randomized contrast. Treating-investigator assessment is part of the endpoint definition, but the record does not report assessor procedures or reliability information.

The enrolled group size is reported as 30, but the record does not identify the analysis population or the number contributing data to each outcome. Missing-data amounts, reasons, and handling methods are not reported. This limits assessment of how representative the analyzed observations may be of the enrolled group.

The registry lists 10 outcome measures, but does not report secondary-outcome results, a multiplicity approach, or a detailed statistical analysis plan. It also does not report the study's own sample-size justification. The planning illustration uses assumptions for equal allocation between two arms, which do not match the recorded single-group design and should not be taken as evidence of observed power.

Other study details relevant to interpretation—including further participant characteristics and product-specific treatment allocation or amounts—are not reported in the registry record. The stated safety counts are descriptive and are not accompanied by a concurrent comparison.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Emervel for the Correction of Lower Face Wrinkles & Folds — NCT02718040.
• Registry record last updated 2022-08-01; status last verified 2018-09.
• Results first posted 2018-09-25.
• 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.

19. Record Summary

The registry record describes a completed Phase 4, multicenter, single-group study of Emervel Classic and/or Emervel Deep for lower-face wrinkles and folds. It lists 30 enrolled subjects, allocation as not applicable, and masking as none. The recorded study start was 2016-04, and primary completion was 2016-07.

The primary outcome is the number of subjects whose lower-face expression naturalness was at least maintained at 42 days, based on treating-investigator assessment of 2D video. The primary result and analyzed denominator are not reported in the registry record. The record lists 10 outcome measures and multiple assessment types, but does not report secondary-outcome results or a detailed statistical plan.

Safety fields list 0 serious adverse events, 0 other adverse events, and 0 deaths. The study has no concurrent control group, so these figures are descriptive rather than comparative.