Clinical Study to Evaluate the Efficacy of an Over-the-counter (OTC) Sunscreen Lip Balm: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Clinical Study to Evaluate the Efficacy of an Over-the-counter (OTC) Sunscreen Lip Balm (NCT05082376), a randomized na study. The primary outcome is Mean Change From Baseline in Corneometry Value at Each Post-treatment Timepoint.

2. Clinical Question

The clinical question is about an instrumental measure of skin hydration over a limited period after one application. Corneometry records capacitance, expressed in arbitrary units; a higher reading indicates more hydration. The study also lists the percentage of participants with improved corneometer measurement as a secondary outcome, but numerical findings for that measure are not reported in the registry record. The question is therefore narrower than whether repeated use, longer-term use, or other outcomes differ: the record concerns change in measured hydration during the stated post-treatment period.

3. Trial Design

The registry describes a completed randomized, parallel-group clinical study with no masking. It lists enrollment of 38 participants and the study condition as sunscreening agents. The study began on 2021-11-01, reached primary completion on 2021-11-11, and has a completed status. Its phase is listed as NA. The sponsor is HALEON.

Participants were assigned to a test arm or a control arm. In the test arm, one topical application of CLM Original was applied to the assigned test site using a fingercot, then spread evenly with light pressure. In the control arm, no treatment was applied to the assigned control site. The product description specifies 80 +/- 2 milligrams, equivalent in the record to 2.0 +/- 0.05 milligrams per centimeter squared. The record does not state the allocation ratio or the number of participants assigned to each arm.

The primary outcome was mean change from baseline in corneometry at each post-treatment timepoint: 2, 4, 6, and 8 hours. The record describes a baseline assessment before treatment and post-treatment assessments at those times. It also lists a secondary outcome concerning the percentage of participants with improved corneometer measurement. These descriptions establish the intended measurement schedule and outcome types, but numerical outcome results are not reported in the registry record.

The trial design offers a comparison between application of the balm and no treatment within the study’s specified setting and follow-up window. Because masking is listed as none, participants and study personnel were not masked according to the record. The registry does not report further details about allocation procedures, assessor masking, site selection, or the sample-size justification. Those details cannot be inferred from the randomized, parallel-group designation alone.

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: Two test sites on each participant's volar forearms (one site per arm) were randomized to treatment, either ChapStick Lip Moisturizer (CLM) Original (test product) or no treatment (control). Thirty-eight participants were enrolled. Two were lost to follow up during the conditioning phase, thus 36 eligible participants received study treatment.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Primary analysis population: all eligible participants who were randomized, received study treatment and provided at least one post-treatment efficacy assessment.

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: Safety Population: all randomized participants who received study treatment.

6. Primary Endpoint

The registry lists the primary outcome as Mean Change From Baseline in Corneometry Value at Each Post-treatment Timepoint, measured over Baseline (Pre-treatment), 2, 4, 6 and 8 hours post-treatment.

The primary endpoint is mean change from baseline in corneometry at each post-treatment timepoint. Corneometry uses a capacitance sensor to measure the dielectric constant of the stratum corneum, which the record describes as directly proportional to skin water content. Results are expressed in arbitrary units of skin hydration, with a higher value representing more hydrated skin.

At each assessment, the mean of 3 corneometer readings for a test site was calculated for each participant. Change from baseline was defined as the post-treatment value minus the baseline value. This change score focuses on how a participant’s measured value shifted from their own starting measurement, rather than comparing post-treatment readings without accounting for baseline.

Using an instrumental measure makes it possible to quantify change in hydration at the scheduled assessments. The record sets out measurements at 2, 4, 6, and 8 hours, so the endpoint concerns both the direction and pattern of measured change over time. The record does not specify a threshold for a meaningful change in arbitrary units. Nor does it report numerical outcome estimates, so the magnitude and precision of change at any timepoint cannot be assessed from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean change estimate represent?

For each participant and post-treatment assessment, the change score is the post-treatment corneometry value minus that participant’s baseline value. A positive change therefore represents a higher measured value than baseline, while a negative change represents a lower value. The study endpoint then summarizes those participant-level changes using a mean at each timepoint. A mean describes the average change in the analyzed group; it does not imply that every participant changed by that amount or in the same direction.

General statistical context: comparing change scores between arms asks whether the average movement from baseline differs between the groups. This is not the same estimand as a comparison of raw post-treatment values. Baseline adjustment can be handled in different ways, and the registry record does not report the specific statistical model used for the primary analysis. The subtraction used to define the change score is reported, but that alone does not reveal the full analysis method.

Why are there several timepoints?

The primary outcome is assessed at 2, 4, 6, and 8 hours after treatment. Each timepoint can provide a separate estimate of change, allowing the time pattern to be described rather than compressing the follow-up into a single value. Measurements from the same participant across time are generally related: a participant’s values at different assessments may share features. General statistical context: analyses of repeated measurements often account for this within-participant dependence. Treating every reading as unrelated can misstate uncertainty. The registry record does not report whether a repeated-measures model or another method was used.

Corneometry readings are recorded in arbitrary units. Their interpretation depends on the measurement definition: higher values indicate more hydration according to the registry description. The units do not themselves establish how large a difference would be important in practice. A threshold for meaningful change is not reported in the registry record, and no numerical endpoint estimates are reported for comparison.

What does standard deviation describe?

The primary endpoint specifies standard deviation as its dispersion measure. General statistical context: a standard deviation describes how spread out individual values are around their group mean. It is not the same as a confidence interval for the mean, and it does not directly state how precisely the mean has been estimated. A confidence interval, when reported, communicates a range of values compatible with the data and the analysis assumptions. No primary confidence intervals are reported in the registry record, so the precision of the mean changes and arm comparisons cannot be evaluated from this record.

Standard deviations also help readers understand whether a mean represents a fairly concentrated set of individual changes or a more variable set. Similar means can coexist with different degrees of individual variability. Conversely, variability does not show whether a comparison between means is statistically distinguishable without the relevant estimate and its uncertainty. The registry record identifies the planned dispersion statistic, but numerical outcome summaries are not reported.

What does randomization contribute?

General statistical context: random assignment is intended to make treatment groups comparable, on average, with respect to measured and unmeasured factors at the point of assignment. In a particular trial, chance imbalances can still occur, especially when group sizes are limited. Randomization does not by itself eliminate missing outcome data, measurement error, or bias introduced after assignment. The record identifies the study as randomized, but does not report the allocation sequence method, concealment procedures, or arm sizes.

The trial is also described as parallel-group and unmasked. General statistical context: in a parallel-group design, assigned groups are compared over the study period; masking, when used, can limit some expectations from influencing conduct or measurement. The registry says masking was none. It does not report whether outcome assessors were separately masked, so no conclusion about assessor masking should be drawn.

How should significance and sample-size illustrations be read?

The record’s planning assumptions specify a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It describes the effect for planning as a stated fraction of the observed effect. These assumptions are distinct from a report of the trial’s own design justification, which is not reported in the registry record. The registry also does not report the specific test or model used for the outcome analyses.

General statistical context: a significance level is a decision threshold used in a specified statistical testing procedure; it is not the probability that a particular result is true. A p-value, if reported, would describe how compatible the data are with a specified null model under the analysis assumptions. It would not measure the size or practical importance of an effect. No primary p-values are reported in the registry record.

Planning estimates of participants per arm for a target power are illustrations based on assumptions about an effect and variability. They are not observed power and do not describe the trial’s actual outcome. The registry’s sample-size assumptions refer to fractions of the observed effect, but numerical planning estimates are not reported in the registry record. No effect size should be inferred from the existence of those assumptions.

Why can over-dispersion matter?

General statistical context: over-dispersion means that observed variability is greater than a statistical model expects. When a model assumes less variability than the data contain, standard errors can be too small and uncertainty can be understated. This is relevant in some kinds of data, especially counts or clustered observations, but the registry describes the primary outcome as a continuous mean measure and does not report an over-dispersion assessment. It would therefore be inappropriate to claim that over-dispersion occurred in this study.

More broadly, the choice of statistical method should match the outcome, design, repeated measurements, and data completeness. The registry record gives the endpoint definition and analysis population but does not report enough detail to reconstruct the primary statistical procedure. Interpretations should remain within those limits.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome is recorded at 2, 4, 6, and 8 hours after treatment, and the record lists two outcome measures and four analyses. With multiple timepoint comparisons, the chance of at least one apparently unusual finding can increase if each comparison is interpreted separately without an appropriate plan. General statistical context: multiplicity procedures can control that risk, or an analysis plan can define a primary comparison and treat other estimates as supportive. The multiplicity approach is not reported in the registry record.

The record also does not report whether analyses were adjusted for baseline values beyond defining change as post-treatment minus baseline. It does not describe a method for missing outcome measurements, a rule for excluding observations, or a sensitivity analysis. These details matter because the primary analysis population requires at least one post-treatment efficacy assessment, while the number of participants contributing data at each timepoint is not reported.

The primary population is defined as all eligible randomized participants who received study treatment and contributed at least one post-treatment efficacy assessment. This definition identifies the intended set for primary analysis, but the registry does not report how many participants met it or whether all eligible participants were analyzed as defined. Enrollment was 38; the adverse-event listing has 36 participants at risk for each of its two categories. Those figures do not establish how many efficacy observations were missing, and the record does not reconcile them.

The record does not report imputation, last-observation methods, or other handling of missing efficacy values. It also does not report whether analysis populations differed for the primary and secondary outcomes. Those omissions limit assessment of how incomplete follow-up may affect the estimates, independently of whether the planned measurement schedule was followed.

11. 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.

The registry lists an all-study-participants safety group with 36 participants at risk for serious adverse events and 36 at risk for other adverse events. It reports 0 participants affected by serious adverse events, 0 affected by other adverse events, and 0 deaths. No serious adverse event terms are listed.

These figures describe what is recorded for the stated safety group; they do not establish that no adverse events of any kind occurred outside the categories shown. The registry record does not give further event detail, such as event types other than the listed serious-event terms, timing, severity definitions, or a fuller account of collection and reporting methods. The absence of listed serious-event terms should not be expanded into a claim about every possible safety outcome.

The safety denominators are not the same as the enrollment figure of 38, and the record does not explain the difference. They also do not identify the primary efficacy analysis population or the number with corneometry data at each timepoint. The safety summary should therefore be read separately from the efficacy endpoint. It reports the stated participant counts and event counts, not a comparison of event risk between arms or a complete account of all possible harms.

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

This study is designed to assess measured hydration after a single application of OTC sunscreen lip balm, using corneometry at scheduled timepoints through 8 hours. The registry record identifies the randomized parallel-group comparison, defines change from baseline, and describes the no-treatment control. Those details explain the question the study set out to address.

The record does not report numerical primary outcome results. It therefore does not show how much the mean corneometry value changed in either arm, whether the arms differed at any timepoint, or how uncertain any estimated difference was. The listed secondary outcome also has no numerical findings in the registry record. The study’s stated objective and the existence of a completed status cannot substitute for outcome estimates.

Even with numerical results, a measured change in arbitrary units would need to be interpreted in light of the endpoint’s meaning, its variability, and the precision of the estimate. A statistical difference would not automatically establish that a change was important in practical terms. The registry does not report a threshold for meaningful change. No conclusion about the size or importance of a hydration difference can be drawn from the available outcome reporting.

The study concerns one application and a defined short follow-up period. It does not, from the information in the registry record, answer questions about repeated use, longer-term effects, other products, or outcomes beyond the stated corneometry measures. The no-treatment control also means the described comparison is not an active-product comparison.

The safety listing reports no serious adverse events, no other adverse events, and no deaths among the stated at-risk counts. Those entries are limited to the registry’s reported categories and denominators; they do not replace a complete safety analysis. Overall, the record documents the design and planned measurement framework, but its missing numerical efficacy results prevent conclusions about the observed treatment contrast.

13. Why This Trial Matters Statistically

This study illustrates how an outcome definition shapes the question a trial can answer. The primary measure is not a general assessment of product performance: it is mean change in an instrumental hydration reading from baseline, calculated separately at multiple post-treatment times. Naming the measure, its units, the direction of interpretation, and the subtraction rule makes the intended estimand more transparent.

The timepoints also make the analysis more complex than a single endpoint comparison. Repeated observations from the same participant are related, and multiple time-specific comparisons require careful interpretation. Reporting the estimates with measures of uncertainty and explaining the analysis method would help readers judge both the trajectory and the precision of any differences. Those numerical results and methods are not reported in the registry record.

The randomized, parallel-group design and no-treatment control define a specific comparison. The absence of masking adds important context for how the study was conducted, while the record does not establish whether outcome assessors were masked. Distinguishing known design features from unreported details is an essential part of statistical reading.

The record also shows why safety denominators, enrollment, and efficacy populations should not be treated as interchangeable. The enrollment figure is 38, while the adverse-event group lists 36 participants at risk; the primary efficacy population has its own definition. Without a reconciliation or timepoint-specific analysis counts, readers cannot determine the extent of missing efficacy data.

Finally, this record demonstrates the difference between a study objective and evidence about an outcome. A clear protocol question can be described even when numerical results are absent, but the effect and its precision cannot be assessed without those results. That distinction is central to responsible interpretation of clinical-trial records.

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 principal limitation for interpreting efficacy is that numerical results for the primary and secondary outcomes are not reported in the registry record. There are no reported mean changes, between-arm estimates, confidence intervals, or p-values for the corneometry assessments. Consequently, the magnitude, direction, and precision of the measured effects cannot be evaluated.

The study is unmasked according to the registry. This is relevant context for trial conduct and may matter when decisions about treatment, measurement, or recording could be influenced by expectations. Corneometry is an instrumental measure, but the record does not describe assessor masking or other safeguards. No claim about the effect of unmasking on the results can be made from the available information.

The study addresses a single application and follows the stated outcome through 8 hours. The record does not establish whether findings extend to repeated applications or longer periods. It also does not report participant characteristics or detailed eligibility criteria, limiting assessment of which groups the study population represents. The phase is listed as NA.

The record does not report the statistical model, test procedure, multiplicity handling, missing-data methods, allocation ratio, arm sizes, or a sample-size justification. It defines the primary analysis population but gives no count for participants meeting that definition or contributing at each timepoint. Enrollment of 38 and safety denominators of 36 cannot be used to fill those gaps, and the registry does not explain their difference.

Finally, the no-treatment comparator answers a narrower question than a comparison with another active product. The posted safety counts are also limited to their reported categories and denominators. These limitations concern what can be learned from the registry record; they do not establish that any particular design or analysis choice changed the outcome.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Clinical Study to Evaluate the Efficacy of an Over-the-counter (OTC) Sunscreen Lip Balm — NCT05082376.
• Registry record last updated 2024-04-19; status last verified 2024-04.
• Results first posted 2024-04-19.
• 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.

18. Record Summary

The registry record describes a completed randomized, unmasked, parallel-group study sponsored by HALEON, with enrollment of 38. It evaluates one topical application of CLM Original against no treatment, with corneometry measurements planned at baseline and 2, 4, 6, and 8 hours after treatment. The primary endpoint is mean change from baseline in corneometry value, expressed in arbitrary units.

The primary analysis population is defined as eligible randomized participants who received study treatment and contributed at least one post-treatment efficacy assessment. A secondary outcome concerns the percentage of participants with improved corneometer measurement. Numerical results for these efficacy outcomes, the detailed statistical analysis method, and missing-data handling are not reported in the registry record.

The safety listing reports 36 participants at risk for serious adverse events and 36 at risk for other adverse events, with 0 affected in either category and 0 deaths. The record does not reconcile those safety counts with enrollment or report a numerical efficacy comparison.