Evaluation of the Ulthera System for Treating Axillary Hyperhidrosis: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Evaluation of the Ulthera System for Treating Axillary Hyperhidrosis (NCT03320096), a na na study. The primary outcome is Number of Participants With Hyperhidrosis Disease Severity Scale (HDSS) Score Reduction at Day 30 Post Second Treatment.

2. Clinical Question

3. Trial Design

This completed study evaluated the Ulthera System for axillary hyperhidrosis. It is recorded as a single-group study with one listed intervention: microfocused ultrasound with visualization. Allocation is recorded as NA, and masking is listed as NONE. No randomized comparison or control arm is described. The phase is recorded as NA.

The registry record lists enrollment of 20. The listed start date is 2016-12-13, and the primary completion date is 2017-06-19. The status is COMPLETED. These record details describe the study’s administrative design and conduct; they do not establish how many enrolled participants received treatment, completed follow-up, or entered each analysis population. Those counts are not reported in the registry record, apart from the safety denominators described in the adverse-event record.

The primary outcome is the number of participants with an HDSS score reduction at the post-treatment assessment. The listed secondary outcomes concern HDSS score reduction at Day 90, gravimetric axillary sweat reduction of at least 50 percent at Days 30 and 90, and improvement with the starch iodine test at Days 30 and 90. The registry record lists four outcome measures, but does not provide efficacy results for these outcomes.

The study design is important for interpretation. With a single group and no listed comparator, observations can describe what was recorded among participants who received the intervention, but cannot by themselves separate treatment-associated change from other possible explanations for change over time. The registry record does not report a detailed protocol, treatment schedule, or statistical analysis plan.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Before assignment: A total of 20 participants were screened, enrolled and treated in the study.

Overall Study

Analysis population for the primary outcome, as defined in the registry: All evaluable treated participants in FAS who received a complete or partial study treatment and completed a follow-up visit at Day 30 post second treatment. The FAS was the subset of participants in SES for whom primary efficacy variable was available. The SES was the subset of all participants who were exposed to study treatment at least once.

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: Full analysis set (FAS) was the subset of participants in the safety evaluation set (SES) for whom the primary efficacy variable was available (that is, all participants who had baseline and at least one post-baseline value of the primary efficacy variable). SES was the subset of all participants who were exposed to study treatment at least once.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants With Hyperhidrosis Disease Severity Scale (HDSS) Score Reduction at Day 30 Post Second Treatment, measured over Day 60 (30 days post second treatment).

The primary endpoint is a count: the number of participants whose HDSS score decreased from a baseline score of 3 or 4 to a score of 1 or 2 at the post-treatment assessment. The HDSS is described as a validated, qualitative measure of axillary hyperhidrosis severity and its effect on daily activities. Its four categories range from sweating that is never noticeable and never interferes with daily activities to sweating that is intolerable and always interferes. The middle categories describe sweating that is tolerable but sometimes interferes, or barely tolerable and frequently interferes.

This type of endpoint is used to capture a participant-level change in reported symptom severity and daily-life interference, rather than only a physical measurement of sweat. The success definition requires both the stated baseline category and a lower category at follow-up; a change that does not meet those categories would not satisfy the registry’s definition of success. The endpoint is therefore a binary participant outcome summarized as a count, not a continuous average score.

There is a timing inconsistency in the registry wording: the endpoint title refers to Day 30 post second treatment, while the timeframe is recorded as “Day 60 (30 days post second treatment).” The record does not resolve this difference. Most importantly, the number of participants meeting the success definition is not reported in the registry record, so the endpoint’s observed result cannot be described.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary outcome is recorded as a number of participants with an event, where the event is meeting the specified HDSS reduction definition. This is a binary outcome at the participant level: each participant either meets the definition or does not. The registry describes the endpoint as a count, not as a mean change in score. The number meeting the definition is not reported in the registry record, and no analysis result is listed.

What a count can and cannot show

A count describes how many participants had the defined outcome in the group being assessed. By itself, it does not show how that count compares with what would have happened without treatment. In a randomized comparative study, a treatment contrast can be estimated by comparing groups under the study’s analysis plan. This study is recorded as single-group, with no comparator listed, so no between-group contrast is available in the registry record.

General statistical explanation: a proportion is often used to describe a binary outcome, and an interval around that proportion can convey uncertainty. The registry’s posted primary endpoint is a count, and no proportion or interval is reported. No additional percentage or interval can be inferred from the available record without performing a new calculation, which would not replace a prespecified analysis.

Why uncertainty matters

General statistical explanation: an estimate from a study is subject to sampling variability. A confidence interval communicates the range of effect values reasonably compatible with the data under the chosen method and assumptions. Narrower intervals usually indicate greater precision, while wider intervals indicate less precision. A p-value, when reported, evaluates how compatible data are with a specified null model; it does not measure the size or importance of an effect. Neither an interval nor a p-value is reported for the primary outcome in the registry record, so statistical precision and evidence against a null hypothesis cannot be assessed.

For binary outcomes, the selected analysis method can depend on the number of participants and the pattern of event counts. General statistical explanation: methods based on large-sample approximations may be less reliable when counts are sparse, while exact or other small-sample methods may be considered in some settings. The registry record does not identify the method used, the number of participants in the primary analysis, or the outcome count. It is therefore not possible to judge which method would have been selected or whether any method’s assumptions were met.

Over-dispersion and outcome variation

General statistical explanation: over-dispersion arises when observed variation is greater than expected under a statistical model. It can make standard errors too small if the model does not account for the extra variation. This concept is most relevant to particular count or clustered-data models; the registry’s primary endpoint is a participant count for a binary outcome, and the record does not report a model or evidence of over-dispersion. It would not be appropriate to claim that over-dispersion occurred in this study.

Planning assumptions are not trial results

The registry records a planning illustration based on a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It describes the effect to detect as a stated fraction of the observed effect. For time-to-event planning, the framework refers to a total number of events; for other outcomes, it refers to participants per arm. These are planning conventions, not observed outcomes. The trial is single-group, and no calculated sample-size values or observed effect are reported. Therefore, the illustration does not establish the sample-size rationale used by the investigators, and it cannot be interpreted as observed power.

General statistical explanation: power is a design property calculated under specified assumptions about an effect, variability, significance level, and sample size. It is not a measure of whether a completed study has found a true effect. Retrospective “observed power” based on the observed result does not add useful information beyond the estimate and its uncertainty. No study-specific power calculation or sample-size justification is reported in the registry record.

Study design and inference

The study is listed as single-group, with allocation NA and masking NONE. General statistical explanation: random allocation, when used, helps make comparison groups similar on average with respect to measured and unmeasured factors. Masking can reduce the influence of expectations on some aspects of measurement and assessment. Neither a randomized control group nor masking is listed in this record. This design context limits causal comparison; it does not establish that any particular bias occurred.

The primary endpoint description refers to an FAS of evaluable treated participants and an SES subset, but the registry text ends before completing the SES definition. The full analysis populations, the number included in each, and the rules for handling incomplete observations are not reported in the registry record. Since the endpoint result itself is also absent, no analysis population or missing-data method can be evaluated from the posted information.

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("Ultherapy Treatment")
n      <- c(20)
events <- c(11)
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  Ultherapy Treatment  20  11  55.0  31.5  76.9  34.2  74.2  34.0  74.3

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary HDSS endpoint and three secondary outcome descriptions: HDSS reduction at Day 90, gravimetric axillary sweat reduction of at least 50 percent at Days 30 and 90, and starch iodine test improvement at Days 30 and 90. The record lists four outcome measures overall. It does not provide outcome results or describe whether or how the investigators adjusted for testing multiple outcomes.

General statistical explanation: when several outcomes or time points are tested, the chance of obtaining at least one apparently unusual result can increase if each is assessed independently. A multiplicity strategy may define which endpoint is primary, control the overall error rate, or treat secondary analyses as exploratory. The registry record does not report such a strategy. It also does not report a hierarchy among the secondary outcomes or a prespecified sequence of testing.

The primary population description refers to evaluable treated participants in the FAS who received a complete or partial study treatment and completed a follow-up visit at Day 30 post second treatment. It further describes the FAS as a subset of the SES for whom the primary efficacy variable was available. The explanation of SES is incomplete in the registry record. The complete definitions, population counts, and analysis rules are therefore not reported.

Missing-data methods are not reported in the registry record. It does not explain how participants without the relevant follow-up assessment were handled, whether any outcomes were imputed, or whether sensitivity analyses were conducted. These details matter because the observed count could depend on which participants are included. The record also lists zero analyses, so there are no posted analysis outputs with which to assess the handling of missing observations or multiplicity.

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 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry’s safety record lists 20 participants at risk for serious adverse events and 20 at risk for other adverse events. It records zero participants affected by a serious adverse event and 18 affected by an other adverse event. These are participant counts in the listed Ultherapy Treatment group.

The “other” category is not further described in the record. No event terms, severity details, timing, duration, relatedness to treatment, or overlap between categories are reported. The counts therefore cannot identify what kinds of events occurred or whether they were considered treatment-related. The record also does not give information about how events were collected or assessed.

Zero recorded serious adverse events means that none are listed among the 20 participants at risk in this registry entry. It does not establish that serious events are impossible, nor does it provide a precise estimate of uncommon risks. Likewise, the count of 18 participants with an other adverse event does not show the number or nature of events per participant. These safety figures should be read as registry counts, not as a complete characterization of safety.

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

The registry record establishes that a completed, single-group study evaluated microfocused ultrasound with visualization using the Ulthera System for axillary hyperhidrosis. It describes an HDSS-based primary endpoint and several secondary outcomes, and lists safety counts. It does not report the number of participants who met the primary endpoint definition or provide results for the secondary outcomes. Accordingly, the posted record does not allow the primary efficacy question to be answered.

The endpoint definition is clinically interpretable in terms of reported sweating severity and interference with daily activities: it requires a baseline HDSS score of 3 or 4 and a follow-up score of 1 or 2. But an understandable outcome definition is not itself an outcome result. Without the result count, analysis population size, and uncertainty estimate, neither the observed frequency of success nor its precision can be assessed.

The single-group design also means the registry does not offer a contemporaneous control comparison. General statistical interpretation: a change measured after treatment may be associated with the treatment period, but a single-group study cannot isolate the treatment’s effect from other influences as a randomized comparison can. This is a limitation of the design, not a claim that any particular alternative explanation caused a change.

The safety record reports zero participants with a serious adverse event and 18 with an other adverse event among 20 at risk in each category. Those counts give limited descriptive information because the kinds of other events and their details are not reported. They do not resolve the efficacy question.

Thus, the evidence in the registry record is incomplete for judging the primary endpoint. The record supports a description of what the investigators intended to measure and the design context, but it does not support a conclusion about the magnitude, precision, or comparative effect of the intervention.

14. Why This Trial Matters Statistically

This study illustrates why a clearly defined endpoint and a reported result are both needed for statistical interpretation. The primary outcome is specified as a count of participants meeting a threshold-based HDSS improvement definition. That definition provides a rule for classifying success, but the registry record does not report how many participants met it. Without that count, the central efficacy summary is unavailable.

The design is also statistically important. The study is recorded as single-group, without allocation to a comparator, and masking is listed as NONE. A single-group design can describe participants’ outcomes following an intervention, but it cannot supply a randomized between-group estimate. In general, an outcome observed after treatment does not by itself show what would have happened in the absence of treatment. This distinction matters when readers interpret before-and-after clinical measurements.

The listed follow-up outcomes include both participant-reported HDSS scores and other assessments of sweat reduction or improvement. Multiple outcomes and time points can raise questions about how the primary outcome was prioritized and how statistical testing was handled. Those analysis details are not reported in the registry record, so it is not possible to assess multiplicity procedures or determine whether the secondary outcomes were treated as confirmatory or exploratory.

Finally, the record demonstrates the difference between administrative completion and statistical reporting. The status is COMPLETED, yet efficacy analyses are not listed and outcome results are absent. The available safety counts provide some descriptive information, but they do not replace efficacy estimates or characterize event types. For clinical researchers and biostatisticians, the key lesson is to distinguish endpoint definitions, design features, and observed results: each answers a different question, and the first two do not fill in for the third.

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 main limitation specific to this registry record is the absence of posted efficacy results. Although the primary and secondary outcome definitions are listed, no participant counts for those outcomes, effect estimates, confidence intervals, or p-values are reported. The record lists zero analyses. The primary question therefore cannot be evaluated from the posted results.

The single-group design has no listed comparator and is not recorded as randomized. This limits comparative inference. Masking is listed as NONE, and the registry does not describe any procedures that might reduce the influence of expectations on assessment. These design characteristics do not prove that bias occurred, but they should be considered when interpreting any outcome data if results become available.

The primary endpoint timing is worded inconsistently: its title states Day 30 post second treatment, while its timeframe states “Day 60 (30 days post second treatment).” The registry record does not clarify the discrepancy. The primary population description is also incomplete: it begins to define the FAS and SES but ends before finishing the SES definition. Counts in the analysis populations and complete eligibility rules are not reported.

The registry does not report the study’s statistical analysis plan, sample-size justification, missing-data procedures, multiplicity strategy, or sensitivity analyses. The planning illustration assumptions do not supply those study-specific details, and no calculated planning values are listed. The safety record gives counts but not event terms, severity, timing, relatedness, or overlap. These omissions restrict interpretation of both efficacy and safety.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Evaluation of the Ulthera System for Treating Axillary Hyperhidrosis — NCT03320096.
• Registry record last updated 2019-07-10; status last verified 2017-10.
• Results first posted 2019-07-10.
• 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

NCT03320096 is a completed, single-group study titled “Evaluation of the Ulthera System for Treating Axillary Hyperhidrosis.” The registry lists enrollment of 20, the Ulthera System and 7-3.0mm transducer, allocation NA, and masking NONE. The listed study dates are 2016-12-13 and 2017-06-19 for start and primary completion.

The primary outcome is the number of participants whose HDSS score decreases from 3 or 4 at baseline to 1 or 2 at follow-up. Secondary outcomes concern HDSS reduction, gravimetric sweat reduction, and starch iodine test improvement. Efficacy results and analyses are not reported in the registry record. The safety record lists zero participants with a serious adverse event and 18 with an other adverse event among 20 at risk in each category.

The single-group design provides no listed control comparison. The endpoint timing and analysis-population descriptions contain unresolved or incomplete wording, and details of the statistical plan, missing-data handling, multiplicity, and event types are not reported.