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 Image Guided Targeted Photoablation for the Treatment of Localized Hyperhidrosis (NCT04178161), a randomized na study. The primary outcome is Gravimetric Measurements of Changes in Sweat Production.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04178161 |
| Phase | NA |
| Condition | Hyperhidrosis |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Massachusetts General Hospital |
| Results posted | Yes |
2. Clinical Question
Population
People with hyperhidrosis were the intended population. The registry describes test sites on the palms and notes that one subject missed week 1 and week 3 visits. Further eligibility criteria and the characteristics of the enrolled subjects are not reported in the registry record.
Intervention
The intervention was laser treatment of sweat glands at a selected palm test site. The registry describes the approach as image-guided targeted photoablation.
Comparator
The comparator was an untreated test site on the palm. The registry says test sites were randomized to treatment or control sides.
Primary question
The primary outcome was gravimetric measurement of changes in sweat production, in grams, assessed at baseline, week 1, week 2, week 4, month 3, and month 6. The registry record does not report a numerical comparison of treated and untreated sites.
The clinical question is whether sweat production measured at a treated palm site differs from production at an untreated site over the recorded assessment schedule. The design description assigns treatment or control to palm test sites, rather than describing a comparison between separate treatment groups of people. The record classifies the study as randomized and parallel, with no masking.
The registry explains the rationale as investigating whether an image-guided laser can specifically ablate eccrine sweat glands. It also describes hyperhidrosis as excessive sweating and notes that the condition can affect quality of life. These statements motivate the study; they are not evidence of a treatment effect.
The record does not report numerical outcome values, a treatment-effect estimate, uncertainty intervals, or a statistical test for the primary outcome. It therefore does not establish whether the measured sweat production differed between the treated and untreated sites. The extent to which the findings could apply beyond the recorded palm test sites is also not reported in the registry record.
3. Trial Design
The registry classifies this as a randomized, parallel study with no masking. Its intervention is listed as a device called laser treatment. The arm descriptions specify that two test sites are chosen on the palms and randomized to treatment or control sides: the treatment side receives laser treatment of sweat glands, while the control side is untreated. The registry lists enrollment as 2.
The site-level description is important when interpreting the design. It indicates a treated side and an untreated side, but does not provide a detailed account of how the two sides relate to each participant, how randomization was implemented, or how allocation was concealed. Those details are not reported in the registry record. The broad “parallel” classification is recorded alongside the side-based description; the record does not explain that design terminology further.
The primary outcome is a continuous measure expressed in grams, with the mean and standard deviation specified as the summary measures. The stated assessment schedule is baseline, week 1, week 2, week 4, month 3, and month 6. The outcome description says sweat collection follows exercise on a stationary bike until sweating is observable. After the site is dried, a pre-weighed filter paper under an occlusive dressing is applied for five minutes; the materials are then weighed before and after sweating, and sweat production rate is calculated.
The study status is terminated. The registry lists a start date of 2016-09-01 and a primary completion date of 2021-05-01. The record does not report why the study was terminated, the intended enrollment target, or a sample-size justification. Although the registry lists one outcome measure, it lists zero analyses. No inferential analysis plan or numerical primary outcome results are reported in the registry record.
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 | Treated Side | Untreated Side |
|---|---|---|
| STARTED | 2 | 2 |
| COMPLETED | 2 | 2 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Subject 1 missed week 1 and week 3 visits.
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.
| Characteristic | Unit | All Participants |
|---|---|---|
| Participants analysed | 2 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 2 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 43.5 (SD 26.2) |
| Sex: Female, Male: Female | Participants | 2 |
| Sex: Female, Male: Male | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 2 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Gravimetric measurements of changes in sweat production | grams | 0.1275 (SD 0.0028) |
6. Primary Endpoint
The registry lists the primary outcome as Gravimetric Measurements of Changes in Sweat Production, measured over Assessed at baseline, week 1, week 2, week 4, month 3, and month 6.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | grams |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is titled “Gravimetric Measurements of Changes in Sweat Production.” It measures sweat collected at a palm test site by weighing absorbent materials before and after sweating. Participants are asked to exercise on a stationary bike until sweating is observable. The site is dried, then a pre-weighed filter paper under an occlusive dressing is applied for five minutes. The dressing and absorbent pad are weighed before and after collection, and the rate of sweat production is calculated. The outcome is expressed in grams, with the mean and standard deviation specified.
In general, a gravimetric measure uses weight to quantify collected material. For this endpoint, the aim is to capture sweat production at a localized site rather than rely only on a person’s description of sweating. Measurements are scheduled at baseline, week 1, week 2, week 4, month 3, and month 6, allowing the registry’s intended assessment to span multiple time points.
The registry record does not provide the measured values, the precise calculation used to convert the collected weight to a rate, or the results at any assessment. It therefore does not show the size or direction of any change in sweat production. The record also notes that Subject 1 missed week 1 and week 3 visits; the scheduled measurement list does not include week 3. It does not explain this difference in visit descriptions.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a randomized comparison between a palm site receiving laser treatment and an untreated palm site. It also specifies a continuous primary outcome: gravimetric sweat production, expressed in grams, with mean and standard deviation as summary measures. These details describe what was intended to be measured, not what the study found.
No numerical primary outcome results are reported in the registry record. There is no posted mean for either side at any time point, no reported treated-versus-untreated estimate, and no confidence interval or p-value for that comparison. The registry lists zero analyses. Consequently, the direction, magnitude, and precision of any treatment contrast cannot be assessed from this record. It is not possible to determine whether the measured values favored either side or whether any observed difference could be distinguished from random variation.
The enrollment entry is 2, and the record notes missed visits for Subject 1. These registry entries indicate that the record describes a very small study with incomplete attendance, but the available information does not establish the number of measurements contributing to each assessment or comparison. The analysis population, handling of missing measurements, and any exclusions are not reported in the registry record. Without those details, even a complete set of summary values would need careful interpretation; here, the outcome summaries themselves are absent.
The study is marked terminated. The registry does not state why it ended, whether termination was related to recruitment, feasibility, safety, or another reason, or whether any interim review occurred. It would be inappropriate to infer a cause from the status alone. Likewise, the record gives no protocol rationale for enrollment, no planned precision target, and no statistical analysis plan.
The listed assessment schedule includes baseline, week 1, week 2, week 4, month 3, and month 6, while the population note reports missed week 1 and week 3 visits for Subject 1. The record does not resolve the difference between the stated assessment schedule and the week 3 reference. It also does not say whether other scheduled assessments were completed.
In practical statistical terms, this registry entry documents the design and measurement approach but does not provide an efficacy analysis. The absence of a result is not evidence that treated and untreated sites were the same, nor is it evidence that they differed. Any conclusion about the primary outcome would require results and analysis details that are not reported in the registry record.
9. Statistical Methods Explained
The primary outcome is continuous: it is recorded as a gravimetric measure in grams. The registry specifies the mean and standard deviation as its summary statistics. In general, a mean describes the center of a set of measurements, while a standard deviation describes how dispersed individual measurements are around that center. Those summaries can help characterize observed data, but they do not by themselves show whether a treatment contrast is precise or statistically distinguishable from chance variation.
What would a treatment contrast represent?
For this study, the relevant contrast would concern sweat production at treated and untreated palm sites. Because measurements are described at multiple time points, a complete analysis would need to clarify which visits are compared and how changes from baseline are represented. The registry identifies the outcome and visit schedule but does not report a numerical contrast, its standard error, a confidence interval, or a test result. The specific comparison and statistical model are not reported in the registry record.
In general, a confidence interval expresses uncertainty around an estimated effect. A narrower interval indicates greater precision under the assumptions of the analysis, while a wider interval indicates less precision. No confidence interval for the primary outcome is reported in the registry record, so the precision of a possible treatment difference cannot be evaluated.
Why does the design matter?
The arm descriptions say that test sites on the palms are randomized to treatment or control sides. This suggests that the intended comparison is localized to sites, while the registry also classifies the study as parallel. The record does not describe whether measurements from two sites belong to the same participant, how that relationship was handled analytically, or how randomization was carried out. In general, measurements from the same person or linked sites may be correlated rather than independent. An analysis should account for the dependence implied by the actual design, but the registry does not report the model or covariance assumptions used.
The registry says the primary outcome is summarized by a mean and standard deviation. If measurements have markedly unequal variability or a distribution poorly represented by a normal model, the mean and standard deviation may not fully describe their pattern. In general, over-dispersion means that variability is greater than a model assumes; ignoring it can make uncertainty estimates too small. There is no indication in this record that over-dispersion was assessed, and no outcome data are available to assess it independently.
What do the planning assumptions mean?
The record describes planning illustrations based on a stated fraction of an observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. These are planning assumptions, not a report of the study’s own design justification or an observed-power calculation. The record does not report the numerical planning results or the effect estimate on which those illustrations depend. A planning sample size is an illustration of what might be needed under stated assumptions; it is not the number of participants actually analyzed and does not demonstrate that an observed result is reliable.
In general, a two-sided test allows for a difference in either direction. A significance level is a threshold used in a testing procedure; it does not measure the size or importance of an effect. Equal allocation is an assumption about how observations are divided between comparison groups. A normal approximation uses a normal distribution to approximate the behavior of an estimator or test statistic. Whether those assumptions suit a particular analysis depends on the design and data, which are not described sufficiently in the registry record.
What cannot be reconstructed?
The registry lists zero analyses and provides no numerical outcome summaries. There is therefore no basis for recalculating an unadjusted effect from posted summary statistics. No sponsor analysis is reported, and no discrepancy between a sponsor analysis and a recalculation is described. The analysis method, covariate adjustment, treatment of repeated measurements, missing-data procedure, and definition of the analysis population are not reported in the registry record.
General statistical methods can explain how a mean, standard deviation, confidence interval, or test might be interpreted, but they cannot substitute for the missing observations and analysis. In this case, the appropriate conclusion is limited: the record specifies a measurement procedure and intended schedule, but it does not report a statistical estimate of treatment effect or its uncertainty.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome is assessed at baseline, week 1, week 2, week 4, month 3, and month 6. Multiple assessments create more than one opportunity to describe change or compare treated and untreated sites. In general, when several statistical tests are conducted, the chance of at least one apparently notable result can increase unless the analysis plan accounts for the multiple comparisons. The registry record does not report a multiplicity strategy, a prespecified primary follow-up time, or a rule for interpreting results across visits.
The record states that Subject 1 missed week 1 and week 3 visits. Week 3 is not included in the listed assessment schedule, and the record does not explain the discrepancy. It does not report whether the missed assessments were the only missing observations, whether any measurements were taken at other visits, or how missing data were handled. Methods such as excluding incomplete observations, using available measurements, or imputing missing values can lead to different assumptions and conclusions; no such method is reported in the registry record.
The intended analysis population is also not described. The record does not say which participants or sites would be included in a primary analysis, whether any observations were excluded, or whether analysis followed the randomized assignment. Randomization is recorded, but the analysis rules needed to interpret its consequences are not.
Because no outcome results or analyses are posted, the effects of multiplicity and missing data cannot be evaluated empirically. No adjustment method, missingness assumption, or sensitivity analysis is reported in the registry record. These absences limit interpretation of the planned repeated measurements and prevent assessment of whether the available observations support a robust comparison.
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 |
|---|---|---|---|
| Treated Side | 0 | 2 | 0.0% |
| Untreated Side | 0 | 2 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Treated Side | 0 of 2 |
| Untreated Side | 0 of 2 |
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 |
|---|---|
| Treated Side | 0 of 2 |
| Untreated Side | 0 of 2 |
The registry lists serious adverse events, other adverse events, and deaths separately for the treated and untreated sides. For the treated side, 2 were recorded as at risk for serious adverse events and 0 as affected; 2 were recorded as at risk for other adverse events and 0 as affected; deaths were 0. For the untreated side, 2 were recorded as at risk for serious adverse events and 0 as affected; 2 were recorded as at risk for other adverse events and 0 as affected; deaths were 0. No serious adverse-event terms are listed.
These entries describe the registry’s recorded counts; they do not establish that no adverse events occurred outside the record or that the intervention has no safety risks. In general, a zero count in a small study is limited evidence about uncommon events, and a count depends on how events were defined, collected, and reported. The registry record does not provide further information about event definitions, monitoring procedures, timing, or the completeness of safety reporting.
The at-risk entries are shown separately for each side and should be read as recorded, not added together to create a new total. The safety figures also do not replace the missing primary outcome analysis: they address recorded adverse events, not whether sweat production changed.
12. What the Result Does, and Does Not, Mean
The record establishes that investigators planned a randomized study of image-guided laser treatment at palm test sites, with an untreated site as the comparator. It describes a method for collecting and weighing sweat and lists repeated assessments through month 6. It also records enrollment as 2, identifies the study as terminated, and notes missed visits for Subject 1.
What the record does not establish is whether laser treatment changed sweat production. There are no posted numerical outcome values, treatment-effect estimates, confidence intervals, or p-values. Without those, neither the direction nor size of a difference can be stated, and its statistical precision cannot be described. The absence of a posted analysis must not be interpreted as evidence of no effect or as evidence of an effect.
The registry also does not provide enough information to assess how repeated measurements were analyzed, how the site-based randomization was implemented, or how missing visits affected the analysis. It does not report the reason for termination or a sample-size justification. These gaps matter because study design, completeness of follow-up, and analysis choices influence what a comparison can support.
In general, a small study can be useful for documenting feasibility, measurement procedures, or early observations, but the strength of any inference depends on the data and methods actually reported. The registry record does not report enough outcome or analysis information to determine what this study contributes about treatment effects. Its contribution in the record is therefore primarily descriptive: it documents a proposed intervention, comparator, endpoint, schedule, and safety counts, while leaving the principal efficacy question unanswered.
13. Why This Trial Matters Statistically
This study is statistically notable for the gap between a clearly described measurement procedure and the absence of posted outcome analyses. The record specifies a weight-based assessment of sweat collected at palm sites and a repeated schedule from baseline through month 6. Yet it lists zero analyses and does not provide numerical results. That distinction is important: an endpoint description tells readers what investigators intended to measure, while an analysis is needed to show what the measurements indicated.
The design description also illustrates why the unit of comparison matters. The registry describes randomization of palm test sites to treatment or control sides and labels the study parallel. Interpreting such a comparison requires knowing how sites and participants are linked and how repeated observations are handled. The record does not provide those details, so readers cannot assess whether the statistical model reflects the design.
Missing visits and an unclear reference to week 3 further illustrate the importance of transparent follow-up reporting. The stated schedule does not list week 3, yet the record notes a missed week 3 visit for Subject 1. Without an explanation or missing-data analysis, it is not possible to understand which planned measurements were unavailable and how that affected the evidence.
Finally, the terminated status and limited enrollment underscore why registry status should not be mistaken for an outcome. The reason for termination is not reported, and the record does not justify the enrollment. Statistical interpretation requires results, uncertainty, and analysis details—not only a study design and measurement plan. This record makes those distinctions especially clear.
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 registry record offers limited information for evaluating the study. Enrollment is listed as 2, and no participant characteristics or detailed eligibility criteria are reported. The study is marked terminated, but the reason for termination is not reported in the registry record. A planned enrollment target, sample-size justification, and protocol-level explanation of the design are also not reported.
The main limitation for interpreting efficacy is that no primary outcome results or analysis are posted. The record describes the measurement procedure and schedule but provides no observed means, standard deviations, treatment comparison, or uncertainty estimates. It therefore does not support a quantitative conclusion about changes in sweat production.
The description of randomization refers to treatment and control sides at palm test sites, while the study is classified as parallel. The record does not explain the relationship between sites and participants, the randomization procedure, allocation concealment, or the statistical handling of measurements over time. Masking is listed as none. Further details about outcome-assessment masking are not reported in the registry record.
Follow-up information is also incomplete. The primary outcome description lists baseline, week 1, week 2, week 4, month 3, and month 6; a separate note says Subject 1 missed week 1 and week 3 visits. The record does not clarify the week 3 reference, whether other visits were missed, or how missing data were handled. Multiplicity procedures and the analysis population are not reported.
Safety counts are recorded, but event definitions and reporting procedures are not described. These limitations are specific to the information available in the registry record and prevent a fuller assessment of the study’s design, execution, and findings.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Image Guided Targeted Photoablation for the Treatment of Localized Hyperhidrosis — NCT04178161.
- Registry record last updated 2026-06-26; status last verified 2023-11.
- Results first posted 2026-06-26.
- 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
The registry record concerns a randomized study of image-guided targeted photoablation for localized hyperhidrosis, sponsored by Massachusetts General Hospital. The intervention is listed as laser treatment, and the comparator is an untreated palm test site. The study is classified as parallel and unmasked; enrollment is listed as 2.
The primary outcome is gravimetric measurement of changes in sweat production, expressed in grams. Assessments are scheduled at baseline, week 1, week 2, week 4, month 3, and month 6. The record describes a five-minute collection procedure after exercise but reports no numerical outcome results and lists zero analyses.
The study started on 2016-09-01, has a primary completion date of 2021-05-01, and is marked terminated. The reason for termination is not reported in the registry record. Safety entries list zero serious adverse events, zero other adverse events, and zero deaths for both recorded sides. The record notes missed visits for Subject 1 and does not describe how missing data were handled.