Radiofrequency Hyperthermia Safety Study: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Radiofrequency Hyperthermia Safety Study (NCT05399771), a na na study. The primary outcome is Mean Temperature Change- Skin Evaluation on Leg With Device.

2. Clinical Question

The central statistical question is whether the registry record quantifies the skin-temperature change associated with the device and how precisely that change is estimated. It does not: the endpoint is named and characterized, but no mean, standard error, confidence interval or test result is reported. Consequently, the record does not allow readers to assess the magnitude or precision of the temperature change.

The opposite leg is described as unheated, giving the study a potential within-person reference. Such a design can help account for characteristics shared by both legs of a participant. However, the registry record does not report a primary comparison of the heated and unheated legs, or an analysis that accounts for measurements being paired within participants. The registered primary endpoint specifically names the leg with the device.

The question is framed as a safety assessment, not as a test of clinical benefit. The description refers to healthy participants and skin temperature; it does not report a clinical outcome showing improvement in pain, injury, wound healing or blood flow. Those conditions appear in the registry record, but the study summary does not describe participants as having them.

3. Trial Design

The registry describes a completed, single-group study with an enrollment of 20. The phase and allocation are listed as NA, and masking is listed as none. The study start date is 2022-06-27, primary completion is dated 2023-10-23, and the status is COMPLETED. These entries describe the study's registered design and status; they do not establish that every planned assessment or analysis is reported.

According to the study summary, participants were healthy subjects with intact skin on their lower legs. Each participant was to serve as their own control: radiofrequency heating was applied to one leg, while the other was not heated. The arm description identifies a temperature-controlled radiofrequency device, a heating pad applied to the back of the leg, and a compression stocking covering the pad. The summary describes weekly treatments for 4 weeks, followed by re-evaluation 4 weeks after the last treatment to assess continuing tissue changes.

The listed interventions include Laser Doppler, the Radiofrequency Heating System, Thermal Imaging, and Healthcare Questionnaire & Measurement. Their presence in the intervention list does not establish which measures were used for each outcome or how they were analyzed. That information is not reported in the registry record.

A single-group designation and allocation listed as NA do not describe a randomized parallel-group trial. The self-control arrangement may permit comparisons between the two legs, but the registry record does not state that the legs were randomly assigned to heating or non-heating. It also does not report whether treatment application or outcome assessment was standardized in ways that could affect measurement.

The stated enrollment is 20, but the record does not provide a participant flow account explaining how many completed each treatment or follow-up, or how many contributed data to the primary endpoint. The status COMPLETED should therefore be read as a registry status, not as a substitute for outcome-level follow-up and analysis details. A protocol-level explanation of the design choices is not 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

Reasons for not completing this period:

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 Mean Temperature Change- Skin Evaluation on Leg With Device, measured over week 1.

The registered primary endpoint is “Mean Temperature Change- Skin Evaluation on Leg With Device.” It is a continuous measure, expressed in degrees, with the timeframe listed as week 1. The record identifies the parameter as a mean and its dispersion as a standard error. Its stated purpose is to help determine safety during and after dermal application for generating elevated temperatures.

Temperature is directly relevant to an intervention intended to heat skin. A mean change can describe the average shift in the measured temperature for the assessed group. That average alone does not show how much individual participants varied, whether some experienced larger changes than others, or how the heated leg compared with the unheated leg. Those questions require additional summaries or analyses, which are not reported in the registry record.

In general, a standard error describes the precision of an estimated mean rather than the spread of individual measurements. It is useful for understanding how uncertain the estimated average may be, but it cannot be interpreted without its reported value and, ideally, a confidence interval. Neither the endpoint estimate nor its standard error is reported in the registry record.

The endpoint title specifies the leg with the device, while the study summary describes the other leg as unheated. The registry record does not state whether the primary endpoint is calculated relative to a baseline measurement, whether the unheated leg is included in the primary analysis, or how repeated measurements are handled. The endpoint is therefore identifiable as a week 1 mean temperature-change measure, but its operational calculation and result are not available in the record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean describe?

For a continuous outcome such as temperature, the mean is an average across the observations included in the analysis. It can provide a concise description of the group's central measured value or average change. A mean does not show the full distribution: participants can have different measurements even when the group average is the same. The registry record identifies a mean temperature change as the primary endpoint, but does not report its value or the data contributing to it.

The term “change” usually implies comparison with a prior measurement, but the registry record does not state the baseline definition, the exact calculation, or whether the endpoint is an average of individual changes. It is therefore safest to interpret the registered endpoint by its stated name and timeframe, without assuming a particular calculation beyond what is described.

What does a standard error mean?

In general, a standard error expresses the precision of an estimated statistic, such as a mean. It is distinct from a standard deviation, which describes variation among individual observations. A small standard error relative to the mean can indicate a more precisely estimated average, while a large standard error indicates greater uncertainty in that estimate. This general explanation does not determine the precision of this study's endpoint: its standard error is not reported in the registry record.

A confidence interval is a range constructed to express uncertainty around an estimate under a statistical model. It is often more informative than a point estimate alone because it shows a range of values compatible with the analysis and its assumptions. No confidence interval for the primary endpoint is reported in the registry record. Without an estimate and interval, neither the magnitude nor the precision of the temperature change can be evaluated from the registry information.

How does the within-participant design affect analysis?

General statistical principle: measurements from two legs of one participant are likely to share participant-specific features. Treating such measurements as if they came from unrelated people can fail to represent that dependence. A paired analysis instead focuses on the difference within each participant, or otherwise models the repeated measurements as related. This can be an efficient way to compare a heated leg with an unheated leg when both are assessed under comparable conditions.

The registry record describes one heated leg and one unheated leg, but the primary endpoint is titled as a measure on the leg with the device. It does not report a paired comparison, the unheated-leg temperature result, or a model accounting for within-person dependence. It also does not report whether leg assignment was randomized. Thus the design description suggests a potential paired comparison, but the posted outcome information does not show whether or how one was conducted.

Why can measurement timing matter?

Temperature can vary with the timing of measurement and the conditions under which it is taken. In general, a clearly specified measurement schedule and consistent measurement procedures help readers interpret changes over time. The registry identifies week 1 as the primary endpoint timeframe and describes weekly treatment for 4 weeks, followed by a re-evaluation 4 weeks after the last treatment. It does not report detailed measurement procedures, the timing of the week 1 measurement in relation to treatment, or results at the later assessment.

Repeated observations can also require analysis that accounts for measurements from the same person being related over time. The appropriate approach depends on the study question and the actual data collected. The registry record does not report a longitudinal model or another repeated-measures method, so no such method should be inferred.

What does the planning illustration tell readers?

The registry information describes a sample-size planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of the observed effect, and that time-to-event calculations use total events while other calculations use participants per arm.

These are planning assumptions, not observed trial results or a report of the study's own design justification. The described two-arm equal-allocation framework does not map directly onto the study summary's within-participant arrangement, in which each person has one heated and one unheated leg. No sample-size justification is reported in the registry record. Nor does the record give an observed primary effect estimate or planning values that can be interpreted alongside the endpoint. A planning illustration is not observed power and should not be read as evidence about the precision of this completed study.

What can a statistical test establish?

In general, a hypothesis test evaluates how compatible the observed data are with a specified null hypothesis under a statistical model. A p-value does not quantify the size or clinical importance of an effect, and it does not provide the probability that a hypothesis is true. Interpreting a test requires knowing the hypothesis, analysis, estimate and assumptions. The registry record reports no primary test statistic or p-value, and its statistical plan is not reported in the registry record.

Effect estimates and uncertainty intervals are especially important for a continuous safety endpoint because they convey the observed magnitude and its precision. The absence of these results prevents a quantitative interpretation. It does not justify substituting an assumed effect, a planning calculation or the study's completion status for an outcome analysis.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Thermofield Temperature Controlled Radiofrequency ")
n   <- c(20)
m   <- c(6.21)
sp  <- c(0.478)
sd  <- sp * sqrt(n)      # standard errors converted to SDs
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Thermofield Temperature Controlled Radiofrequency   20  6.210  2.138  5.210  7.210

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists 20 outcome measures, including the primary temperature endpoint and secondary outcome labels that repeatedly refer to the number of participants who attended the session. It reports zero analyses. Numerical results for the listed outcomes, the number of participants contributing to each, and explanations for any outcomes not analyzed are not reported in the registry record.

When a study assesses multiple outcomes or makes multiple statistical comparisons, the chance of at least one apparently unusual result can increase. General statistical practice may address this multiplicity by defining a primary outcome in advance, limiting confirmatory tests, or adjusting interpretation or inference. The registry record names a primary endpoint, but a multiplicity strategy or statistical analysis plan is not reported in the registry record. It is therefore not possible to assess how the various outcomes were prioritized or how multiple comparisons were handled.

Missing data can affect both the estimate and the population to which results apply. General methods include describing who was assessed, why measurements were unavailable, and how the analysis handled missing observations. The registry record does not report participant flow, missing outcome counts, reasons for missingness, imputation, or sensitivity analyses. It also does not define an analysis population for the primary endpoint.

The stated enrollment is 20, but the number enrolled is not necessarily the number with complete week 1 temperature measurements or the number included in an analysis. The registry record does not report those counts. It also does not report interim analyses, stopping rules or the statistical plan. These omissions limit assessment of selection, missingness, multiplicity and analytic decisions; they do not by themselves establish that any particular problem occurred.

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.

Most frequent non-serious adverse event terms

The registry record reports zero serious adverse events among 20 participants at risk. It also reports 3 other adverse events among 20 participants at risk. These are counts as recorded, not estimates of comparative risk or proof that an event was caused by or unrelated to the device.

The serious-event count and the other-event count are separate categories in the record. Zero reported serious adverse events should be interpreted narrowly as the count entered in this registry record. It does not mean that all possible symptoms or changes were absent, and it does not provide detail about monitoring or event collection. The registry lists zero deaths.

For the 3 other adverse events, the record does not provide event descriptions, severity, timing, duration, treatment, or investigator assessment of relatedness. It also does not report whether participants could have more than one event, so the count should not be treated as a count of distinct participants. Although 20 participants are listed at risk for the other-event category, the registry does not give an event-level account.

These data are descriptive and should be read alongside the limited outcome reporting. The record does not report a statistical comparison of adverse events between heated and unheated legs, nor a comparison group of separate participants. The counts alone cannot establish a causal relationship, quantify uncertainty, or support a broader safety conclusion.

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

The registry record establishes that a completed, single-group study enrolled 20 participants and was designed to examine a radiofrequency heating device in healthy subjects with intact skin on their lower legs. It describes one heated leg and one unheated leg per participant, a week 1 primary skin-temperature endpoint, and a schedule of weekly treatment for 4 weeks with later re-evaluation. It also records zero serious adverse events, 3 other adverse events, and zero deaths.

It does not report the primary endpoint estimate, its standard error, a confidence interval, a test result or an analysis comparing the legs. Thus the record does not quantify the skin-temperature change or its uncertainty. The absence of a reported result is not equivalent to a finding of no change, just as the presence of a study description is not evidence that a particular change occurred.

The outcome is a temperature measure intended to inform a safety assessment during and after dermal application for generating elevated temperatures. It is not itself a direct measure of clinical benefit. The registry does not report results demonstrating improvement in chronic pain, soft tissue injuries, wound healing or blood flow. Those labels appear among the recorded conditions, while the study summary describes healthy participants.

The adverse-event counts are also limited in scope. The zero serious adverse events and 3 other adverse events are registry counts, but the record lacks descriptions and timing for the other events and does not provide a comparison-based analysis. These entries should not be treated as proof of either the presence or absence of a causal safety effect.

Overall, the record supports a description of the study's intended design and a few safety counts, but it does not provide the quantitative endpoint findings needed to judge the magnitude, precision or statistical interpretation of the primary outcome. No conclusion about treatment efficacy or an individual participant's care follows from these registry entries.

14. Why This Trial Matters Statistically

This study raises a useful statistical distinction between a design description and an interpretable result. The record describes a self-control arrangement, with one heated leg and one unheated leg, but a design description alone cannot show whether the observed measurements differed or how precisely any difference was estimated. For a within-participant study, the handling of paired measurements matters because observations from the same person are related.

The primary endpoint is also a continuous safety measure rather than a clinical benefit outcome. Its interpretation depends on reporting the mean change and its uncertainty, as well as making clear how the change was calculated and when it was measured. The registry names the week 1 measure and identifies standard error as its dispersion statistic, but reports no numerical estimate. That gap illustrates why endpoint registration and endpoint results serve different purposes.

The record also shows why status and enrollment counts should not be confused with analytic completeness. The study is marked COMPLETED and reports enrollment of 20, yet it reports zero analyses and does not state how many participants contributed primary endpoint data. Without that information, readers cannot connect the intended design to a completed statistical analysis.

Finally, the safety counts are most useful when their scope is clear. The registry reports zero serious adverse events and 3 other adverse events, but does not describe the latter events. Counts without context can be repeated accurately, but they do not answer questions about event type, timing, attribution or comparative risk.

Statistically, the central lesson is that conclusions require more than a registered question and a completed status. Transparent estimates, uncertainty measures, participant accounting and a description of the analysis are needed to judge what the data show. Those details are not reported in the registry record.

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 is that the registry record does not report a numerical result for the primary endpoint. It names a mean temperature change on the leg with the device at week 1 and identifies standard error as the dispersion measure, but supplies neither value. The record also reports zero analyses. Consequently, the primary finding and its precision cannot be evaluated.

The study summary describes a within-participant control arrangement, but no comparison result for the heated and unheated legs is reported. The registry does not describe leg allocation, the baseline calculation, or whether a paired analysis was used. These details matter for understanding what contrast the endpoint represents and how the measurements were analyzed.

The listed enrollment is 20, while the record does not report participant flow or the number with primary endpoint data. Missing observations, exclusions from analysis, and the analysis population are not described. The completed status does not resolve these uncertainties.

The population is described as healthy participants with intact skin on their lower legs. Accordingly, the record does not establish that the results apply to people with the listed conditions of chronic pain, soft tissue injuries, wound healing or blood flow. In addition, the primary endpoint timeframe is week 1, while the summary describes treatment for 4 weeks and re-evaluation 4 weeks after the final treatment. Results at those other times are not reported in the registry record.

The safety record reports event counts but does not detail the 3 other adverse events. No event descriptions, timing, severity or relatedness assessment are reported. The sample-size justification, statistical analysis plan, multiplicity approach and missing-data methods are also not reported in the registry record. These limitations concern what can be interpreted from the registered information; they do not establish what procedures may have been used outside the record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Radiofrequency Hyperthermia Safety Study — NCT05399771.
• Registry record last updated 2024-05-03; status last verified 2024-05.
• Results first posted 2024-05-03.
• 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, single-group safety study of a temperature-controlled radiofrequency heating device. It lists enrollment of 20 and describes healthy participants with intact skin on their lower legs serving as their own control, with one leg heated and the other unheated. Weekly treatment for 4 weeks and re-evaluation 4 weeks after the last treatment are described.

The primary endpoint is mean temperature change on the leg with the device at week 1, expressed in degrees, with standard error specified as the dispersion measure. The endpoint result and any statistical analyses are not reported in the registry record. The record lists 20 outcome measures and zero analyses.

Safety entries report zero serious adverse events among 20 at risk, 3 other adverse events among 20 at risk, and zero deaths. Details of the other adverse events are not reported in the registry record. The record does not provide the primary estimate, its uncertainty, a leg-to-leg comparison, participant flow or the analysis plan.