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 Internet Surveys and Their Impact on Adherence for Rosacea (NCT03048058), a randomized phase 4 study. The primary outcome is Adherence (% of Prescribed Doses That Were Actually Taken by the Subject).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03048058 |
| Phase | Phase 4 |
| Condition | Rosacea |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 20 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Wake Forest University Health Sciences |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned adults aged 18 years and older with persistent erythema associated with active rosacea. The brief summary describes a six-month prospective study and an enrollment of 20. The registry record does not report further eligibility details or a fuller description of the enrolled participants.
Intervention
Participants in the survey group received brimonidine topical gel 0.33% and weekly internet surveys. The surveys asked about medication use and included treatment tips and reminders about rosacea triggers. The registry also describes questions about current erythema.
Comparator
The comparison group received brimonidine topical gel 0.33% with standard-of-care follow-up and no weekly survey. The registry describes surveys at the 3 month and 6 month visits for this group.
Primary question
The primary question was whether adherence to topical brimonidine, measured as the percentage of prescribed doses actually taken and assessed using MEMS caps, differed between the survey and standard-of-care groups at 6 months. The posted results give a median value for each group, but the registry record does not report a formal between-group test or a confidence interval for the difference.
3. Trial Design
The registry describes a randomized, single-masked, parallel-group phase 4 trial. Its brief summary characterizes the study as investigator-blinded, prospective, and lasting 6 months. Enrollment was 20, with 10 participants listed in each arm. The registry status is completed. The start date is 2016-05-05, and primary completion is recorded as 2017-06.
Both groups received brimonidine topical gel 0.33%, with instructions to apply it once daily per the package insert described in the brief summary. The intended contrast was the added weekly internet survey and reminders, rather than brimonidine versus no brimonidine. In the survey group, weekly questions asked how often medication had been used and included treatment tips and reminders about rosacea triggers. The standard-of-care group did not receive weekly surveys; surveys were described at the 3 month and 6 month visits.
The registry says the study involved subjects with persistent erythema associated with active rosacea and an age requirement of 18 years and older. It does not report further eligibility criteria, recruitment procedures, the randomization method, allocation concealment, or the identity of the person or people masked. The brief summary calls the study investigator-blinded, while the design record labels masking as single; more detail about how masking was implemented is not reported in the registry record.
The primary outcome was adherence at 6 months. Secondary outcomes listed include lesion count, clinician erythema assessment, patient severity assessment, and several quality-of-life measures. The registry does not report a detailed schedule for every secondary assessment or a fuller protocol for how those outcomes were measured.
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 | Brimonidine Topical Gel 0.33% & Survey | Brimonidine Topical Gel 0.33% & SOC |
|---|---|---|
| STARTED | 10 | 10 |
| COMPLETED | 6 | 6 |
| NOT COMPLETED | 4 | 4 |
Reasons for not completing this period:
| Reason | Brimonidine Topical Gel 0.33% & Survey | Brimonidine Topical Gel 0.33% & SOC |
|---|---|---|
| Lost to Follow-up | 4 | 0 |
| Withdrawal by Subject | 0 | 4 |
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: 20 subjects of both genders aged 18 years and older with the diagnosis of persistent erythema associated with mild to moderate rosacea as defined by an Investigator Global Assessment rating between 2 and 5.
| Characteristic | Unit | Brimonidine Topical Gel 0.33% & Survey | Brimonidine Topical Gel 0.33% & SOC | Total |
|---|---|---|---|---|
| Participants analysed | 10 | 10 | 20 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 10 | 8 | 18 |
| Age, Categorical: >=65 years | Participants | 0 | 2 | 2 |
| Sex: Female, Male: Female | Participants | 6 | 6 | 12 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 10 | 10 | 20 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | Participants | 10 | 10 | 20 |
6. Primary Endpoint
The registry lists the primary outcome as Adherence (% of Prescribed Doses That Were Actually Taken by the Subject), measured over 6 months.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Standard Deviation |
| Unit | percentage of medication use |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint concerns adherence to topical brimonidine over the study period. The registry defines the result as the percentage of prescribed doses that were actually taken by the subject, with assessment using MEMS caps, and identifies the time frame as 6 months. This endpoint addresses medication-taking behavior rather than a clinical measure of rosacea severity or quality of life.
Adherence is relevant to interpreting a treatment study because the amount of medication used can differ from the amount prescribed. In general, a measure of use can help characterize whether participants followed a dosing routine; it does not by itself establish whether a medication changes symptoms or other clinical outcomes. The registry does not describe the cap-monitoring procedures, how readings were translated into the adherence measure, or how missing monitoring data were handled.
The primary result is labelled as a median, with standard deviation listed as its dispersion measure. The reported median values are 8.2 for the survey group and 6.9 for the standard-of-care group. The unit is described as percentage of medication use, but the registry record does not provide more detail about the scale or the distribution of individual adherence measurements. A median describes the central position of ordered observations; it does not give the full distribution. Standard deviation describes spread in relation to the mean, so pairing it with a median does not fully characterize uncertainty around the median.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome values are 8.2 for brimonidine with weekly surveys and 6.9 for brimonidine with standard-of-care follow-up. The registry identifies these as median adherence values at 6 months and lists standard deviations of 5.3 and 4.2, respectively. The groups each have 10 participants listed. These are descriptive summaries of the two arms; the registry record does not report a formal statistical test of the between-group contrast, a confidence interval, or a p-value.
The numerical ordering of the two medians places the survey arm higher than the standard-of-care arm. That ordering alone does not establish that the groups differ beyond what could arise from sampling variability. With small groups, estimates can be sensitive to individual observations, and a median does not reveal how much the groups' participant-level values overlap. The record does not include individual measurements or a distributional summary sufficient to assess that overlap.
The reported spread values should be interpreted cautiously. The outcome is described using a median, while the dispersion is described as standard deviation. A standard deviation is conventionally read in relation to a mean and may not convey the uncertainty or shape of a distribution when paired with a median. Neither the median nor the standard deviation is a substitute for an interval estimate of the between-group effect. No such interval is reported.
The intervention contrast also combines several elements: weekly reporting about medication use, treatment tips, and reminders about rosacea triggers. The registry does not isolate the effect of asking participants to complete surveys from the effect of the accompanying reminders or tips. The design therefore addresses the survey-and-reminder package as described, rather than identifying the contribution of each component separately.
Other listed outcomes include lesion count, clinician erythema assessment, patient severity assessment, and quality-of-life measures. The registry record lists six secondary outcomes but does not provide their results in the posted data described for this trial. It lists zero analyses. That absence means the registry does not provide a basis for interpreting those outcomes statistically; it does not establish that no analyses were ever conducted outside the record.
The safety figures report zero serious adverse events, zero other adverse events, and zero deaths in each group, with 10 participants at risk in each. These counts describe what is recorded, not proof that an event could not occur or that the groups have identical safety profiles. The registry record does not provide event-level details or a longer-term safety assessment.
9. Statistical Methods Explained
The trial is recorded as randomized and parallel-group. In a randomized trial, assignment is intended to create comparison groups without systematically choosing who receives each study condition. Random assignment can reduce bias from known and unknown participant characteristics on average, but it does not guarantee that groups will be alike, especially in a small study. The registry gives the allocation label but does not report the sequence-generation procedure, allocation concealment, or additional details needed to assess those steps.
What does the arm comparison estimate?
Both groups received brimonidine topical gel 0.33%. The intended comparison is therefore between the described survey-and-reminder approach and standard-of-care follow-up without weekly surveys, not between active medication and no medication. Because the survey arm also received treatment tips and reminders, the contrast reflects that combined package as described in the registry. It cannot separate the influence of survey completion from the influence of the reminders or tips.
The posted primary values are arm-level summaries: medians of 8.2 and 6.9, with standard deviations of 5.3 and 4.2. A median is the middle value after observations are ordered, or a central value when the number of observations is even. It is often used when a distribution may be skewed or affected by unusually high or low observations. A mean, by contrast, uses every value in the arithmetic average and can be pulled by extreme observations.
Standard deviation describes how dispersed values are around their mean. It is not a confidence interval and does not directly quantify the precision of a median or the difference between medians. Reporting a median alongside a standard deviation may leave the distribution difficult to assess. The registry does not report an interquartile range, a distribution plot description, participant-level data, or another measure that would clarify the spread around the median.
Why does uncertainty matter?
A point estimate is a summary calculated from the study participants. It is not necessarily the exact value that would be observed in a broader population or in another trial. A confidence interval is a general statistical tool for expressing the precision of an estimate under a specified method. It communicates a range of values compatible with the data and method; it does not guarantee that the true value lies in the interval. The registry record does not report a confidence interval for either arm's median or for a between-group effect.
A hypothesis test is another general tool. It evaluates how compatible the observed data are with a specified statistical null model, given the test's assumptions. A p-value is not the probability that the null hypothesis is true, nor does it measure the size or clinical importance of an effect. No p-value or formal between-group test is reported in the registry record, so the arm summaries should not be described as statistically significant or statistically non-significant.
For a comparison of two groups, an analysis could focus on a difference between means, a difference between medians, or another measure suited to the outcome distribution. Those choices answer different statistical questions and can require different assumptions. The registry identifies the primary parameter as a median but does not report the method used for a between-group comparison. No recalculated comparison is posted, and the reported summaries alone do not determine a unique inferential result.
How should the design be considered?
Single masking is recorded, and the brief summary describes the study as investigator-blinded. Masking can reduce the influence of expectations on assessment or study conduct when the relevant people are unaware of assignments. The registry does not identify who was masked, whether participants knew their group, or how masking was maintained. Since participants in one arm received weekly surveys and those in the other did not, the study procedures themselves differed in a way that may have made group assignment apparent to participants.
In general, over-dispersion means that observed variability is greater than a statistical model expects. If a model assumes too little variability, standard errors can be too small and uncertainty can appear narrower than warranted. The registry does not report a model for the primary outcome or indicate whether over-dispersion was assessed. This concept is relevant when evaluating count or repeated-measure outcomes, but it should not be taken as evidence that a particular model was used in this trial.
The record lists 10 participants per arm for the primary result. That is a small basis for estimating a distribution or identifying modest differences reliably. Small samples do not automatically invalidate a result, but they can leave estimates imprecise and make model assumptions harder to check. The registry does not report a sample-size justification or the statistical plan. Any sample-size planning illustration associated with the posted material should be understood as a hypothetical planning exercise, not as observed power or as evidence about the trial's original design.
The record marks the study completed and lists the primary endpoint at 6 months. It does not report interim analyses, stopping rules, a prespecified analysis population, or the handling of missing outcome data. Those details matter because decisions about which measurements to include and how to handle unavailable observations can affect an estimate. Their absence prevents a full reconstruction of the statistical analysis from the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies adherence as the primary endpoint and lists six secondary outcomes: lesion count, clinician erythema assessment, a general survey of the impact of rosacea on everyday activities, patient severity assessment, quality of life with rosacea, and the Dermatology Life Quality Index. It does not report a multiplicity strategy, such as a hierarchy of tests or an adjustment for considering several outcomes. When many outcomes are examined, the chance of at least one apparently notable result can increase; methods that address multiplicity can help control that risk. This is a general statistical consideration, not evidence that any particular adjustment was or was not applied outside the registry record.
The registry lists zero analyses. The primary arm summaries are posted, but no formal test or interval estimate is reported. The record does not provide results for the listed secondary outcomes in the registry record reported for this trial. It also does not specify whether the endpoint analyses were prespecified in a protocol or statistical analysis plan, or how any deviations were handled.
Missing-data methods and analysis populations are not reported in the registry record. It is therefore not possible to tell from the record whether all randomized participants contributed to the primary summary, whether any monitoring data were unavailable, or how unavailable measurements would have been treated. The arm listings each show 10 participants, but those listings alone do not establish that every participant had a complete primary measurement. The record also does not describe an intention-to-treat, per-protocol, or other analysis population.
These omissions limit assessment of both the reliability of the estimates and the chance of selective reporting. They do not show that data were missing or that analyses were changed; those matters are simply not reported in the registry record.
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 |
|---|---|---|---|
| Brimonidine Topical Gel 0.33% & Survey | 0 | 10 | 0.0% |
| Brimonidine Topical Gel 0.33% & SOC | 0 | 10 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Brimonidine Topical Gel 0.33% & Survey | 0 of 10 |
| Brimonidine Topical Gel 0.33% & SOC | 0 of 10 |
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 |
|---|---|
| Brimonidine Topical Gel 0.33% & Survey | 0 of 10 |
| Brimonidine Topical Gel 0.33% & SOC | 0 of 10 |
For the survey group, the registry lists 10 participants at risk for serious adverse events and 0 serious events; it also lists 10 at risk for other adverse events and 0 other events, with 0 deaths. For the standard-of-care group, the corresponding figures are 10 at risk, 0 serious events, 10 at risk, 0 other events, and 0 deaths. No serious adverse-event terms are listed.
These are recorded counts over the period covered by the trial record. A count of zero means that no events of that category are reported for the listed group; it does not establish that risk is absent. With 10 participants listed per arm, the record provides limited information about uncommon events, and it does not report detailed event descriptions, severity grading, timing, attribution, or follow-up beyond the study period.
The absence of reported events should not be read as a statistical demonstration that the groups have equivalent safety. The registry record does not provide a comparative safety analysis or an interval estimate for event rates. These figures are best read as descriptive reporting from this study, rather than as a precise estimate of safety in a wider population.
12. What the Result Does, and Does Not, Mean
The primary results describe adherence values in two groups receiving the same topical medication but different follow-up procedures. The survey group has a reported median of 8.2, and the standard-of-care group has a reported median of 6.9. The registry identifies the outcome as percentage of prescribed doses actually taken, assessed using MEMS caps at 6 months. The result is therefore a measure of medication use as defined by the record, not a direct measure of rosacea improvement.
The results do not establish whether the numerical ordering between the medians represents a reliable difference. The record contains no formal comparison, confidence interval, or p-value, and each arm has 10 participants listed. There is also no participant-level distribution from which to assess variation, overlap, or sensitivity to individual observations. No conclusion about statistical significance can be drawn from the reported arm summaries alone.
The results also do not isolate the effect of survey completion from the accompanying treatment tips and trigger reminders. Nor do they show whether any adherence pattern was associated with lesion count, clinician-assessed erythema, patient severity, or quality of life. Those outcomes are listed as secondary measures, but their results are not reported in the registry entries for this trial.
In general, adherence and clinical outcomes answer different questions. An adherence summary concerns medication use; clinical outcomes concern symptoms, signs, or quality of life. A study can describe one without establishing the other. The registry record does not provide enough information to assess the relationship between adherence and clinical outcomes in this study.
The findings are specific to the trial as registered: adults with persistent erythema associated with active rosacea, brimonidine topical gel 0.33%, the survey-and-reminder approach described, and the 6-month endpoint. The registry does not report enough detail about participant characteristics or analysis methods to support broader generalization. The posted figures should be treated as descriptive evidence from a small randomized study, with substantial uncertainty about the comparative estimate.
13. Why This Trial Matters Statistically
This trial addresses a statistical question about measurement and behavior as well as treatment: can a structured schedule of internet surveys and reminders be compared with standard-of-care follow-up when both groups are prescribed the same topical medication? That distinction matters. The arm contrast is not medication versus no medication; it is an added communication and monitoring package versus follow-up without weekly surveys.
The trial also illustrates why an endpoint definition needs to be read closely. The primary endpoint is adherence, specified as the percentage of prescribed doses actually taken and assessed with MEMS caps. It is different from a symptom score or a quality-of-life measure. Treating these outcomes as interchangeable would blur the question the primary analysis was intended to address.
Statistically, the registry offers arm-level medians and standard deviations, but no formal comparison or uncertainty interval. This makes it possible to describe the reported values while leaving the precision of the group contrast unresolved. The distinction between a descriptive estimate and an inferential conclusion is central to responsible interpretation, particularly with 10 participants listed in each arm.
The study is also a useful example of how trial records can leave important analysis details unavailable. The record does not report a statistical plan, missing-data procedures, analysis populations, or a multiplicity strategy for the secondary outcomes. Those omissions do not imply misconduct or flawed analyses, but they restrict what can be independently evaluated from the registry record. Clear reporting of those elements would help readers understand how outcome definitions, uncertainty, and multiple comparisons were handled.
Finally, the safety counts show why zero events must be interpreted in context. They record no serious or other adverse events in either arm, but the small groups and limited detail do not establish that no risk exists. The value of this record is in defining the study question and documenting its posted results, while also showing the limits of what those summaries alone can support.
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 posted primary summaries are based on 10 participants listed in each arm. This limits the amount of information available about the distribution of adherence and the precision of a between-group estimate. The registry does not report a confidence interval, formal test, or participant-level values, so the uncertainty around the numerical ordering of the medians cannot be evaluated directly.
The endpoint summary pairs medians with standard deviations. Because standard deviation describes spread around a mean, this pairing does not fully explain the shape or variability of the adherence data around the reported medians. The record does not report an interquartile range or another distributional summary. It also does not give enough detail about MEMS cap procedures to assess exactly how device readings were converted into the adherence measure.
The groups differ in more than survey completion: the survey arm received treatment tips and reminders about rosacea triggers. The study contrast therefore cannot attribute any difference to one component alone. Masking is recorded as single, and the brief summary calls the study investigator-blinded, but the registry does not specify who was masked or how masking was maintained.
Analysis details are also limited. A statistical plan, missing-data procedures, analysis populations, multiplicity methods, and interim analyses are not reported in the registry record. Although six secondary outcomes are listed, their results are not included in the registry record for this trial. The record does not provide enough information to evaluate whether all planned outcomes were reported or how any unavailable measurements were handled.
The registry describes the population and intervention only at a broad level. Additional eligibility criteria and participant characteristics are not reported, limiting assessment of how well the findings might apply beyond this study. The safety record includes zero reported events in each arm but lacks event-level detail and does not establish the absence of risk.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Internet Surveys and Their Impact on Adherence for Rosacea — NCT03048058.
- Registry record last updated 2018-10-10; status last verified 2018-09.
- Results first posted 2018-08-13.
- 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
NCT03048058 is a completed randomized, single-masked, parallel-group phase 4 study sponsored by Wake Forest University Health Sciences. The registry describes a prospective, investigator-blinded study of adults aged 18 years and older with persistent erythema associated with active rosacea. Enrollment is 20, and the primary completion date is 2017-06.
Both groups received brimonidine topical gel 0.33%. One group also received weekly internet surveys, treatment tips, and reminders; the standard-of-care group did not receive weekly surveys and had surveys at the 3 month and 6 month visits. The primary outcome was adherence at 6 months, defined as the percentage of prescribed doses actually taken and assessed using MEMS caps.
The registry reports median adherence values of 8.2 for the survey group and 6.9 for the standard-of-care group, with standard deviations of 5.3 and 4.2. It does not report a formal comparison, confidence interval, or p-value. Six secondary outcomes are listed, while their results are not reported in the registry entries for this trial. The registry records zero serious adverse events, zero other adverse events, and zero deaths in each group.