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 Performance of DAILIES TOTAL1 Daily Disposable Contact Lenses in Habitual Soft Lens Wearers Who Report Substantial Digital Device Use (NCT06308666), a na na study. The primary outcome is Subjective Rating of Comfort After 8 Hours or More of Digital Device Use.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT06308666 |
| Phase | NA |
| Condition | Myopia |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 41 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Waterloo |
| Results posted | Yes |
2. Clinical Question
Population
Habitual soft lens wearers with myopia who identified themselves as substantial digital device users, defined in the study description as at least eight hours of device use per day.
Intervention
Refitting participants with delefilcon A contact lenses, described as daily disposable lenses, and evaluating lens performance.
Comparator
No separate comparator group is listed. The registry describes a single-group study without a randomized comparison.
Primary question
What overall comfort score did participants report after at least eight hours of digital device use at the Day 14+2 assessment?
The study focuses on participants’ subjective experience while wearing the study lenses during substantial digital device use. Comfort is the named primary outcome; the brief description also refers to dryness and vision as symptoms of interest. The registry record does not report the observed primary comfort score, its full range, or numerical results for the other outcomes.
Because there is no separate control group, the record cannot establish a comparative effect against another lens or against continued use of participants’ habitual lenses. Its design instead describes performance evaluation within a refitted group. The target population is narrow: habitual soft lens wearers who report at least eight hours of digital device use per day. The registry record does not report additional eligibility details that would clarify how participants were selected or how broadly the findings might apply.
3. Trial Design
This is a completed, single-group study registered as NCT06308666. The sponsor is the University of Waterloo. The registry lists 41 participants enrolled, the condition as myopia, and the intervention as delefilcon A contact lenses. The arm is named Refit, and its description says participants were refitted and dispensed the lenses before lens performance was evaluated.
The study is not described as randomized, and no comparator arm is listed. Masking is recorded as none. The registry lists the phase as NA and the allocation as NA. These entries do not establish any additional design details beyond the single-group structure recorded. The study began on 2024-03-18, reached primary completion on 2024-10-23, and is marked completed.
The primary endpoint is a subjective overall comfort rating after at least eight hours of digital device use, assessed at Day 14+2. The description specifies a scale from 0, worst, to 100, best, and identifies the summary measure as the median with the full range. Three participants discontinued before the study could be completed. The registry record does not report the number contributing data to the primary endpoint or explain how missing endpoint observations were handled.
The record lists three outcome measures and zero analyses. It does not report a statistical analysis plan, sample-size justification, interim analyses, or an explanation for the enrollment target. The endpoint definition is available, but the observed score and a numerical analysis of the outcome are not reported in the registry record. Consequently, the design can be described, but the primary result cannot be interpreted from the registered outcome information.
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: Out of the 41 participants that were enrolled, 35 met the inclusion critieria, and 35 were dispensed with the study treatment.
Overall Study
| Stage | Refit |
|---|---|
| STARTED | 35 |
| COMPLETED | 32 |
| NOT COMPLETED | 3 |
Reasons for not completing this period:
| Reason | Refit |
|---|---|
| Withdrawal by Subject | 1 |
| Protocol Violation | 2 |
Analysis population for the primary outcome, as defined in the registry: 3 people discontinued before the study could be completed.
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 | Refit |
|---|---|---|
| Participants analysed | 35 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 35 |
| Age, Categorical: >=65 years | Participants | 0 |
| Age, Continuous | years | 25.5 (SD 6.3) |
| Sex: Female, Male: Female | Participants | 29 |
| Sex: Female, Male: Male | Participants | 6 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: Canada | participants | 35 |
6. Primary Endpoint
The registry lists the primary outcome as Subjective Rating of Comfort After 8 Hours or More of Digital Device Use, measured over Day 14+2.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Full Range |
| Unit | score on a scale |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is participants’ subjective overall comfort rating after at least eight hours of digital device use. It is assessed at Day 14+2 on a scale running from 0, worst, to 100, best. The registry specifies the median and full range as the intended way to summarize the score. The observed median and range are not reported in the registry record.
Comfort is relevant to the study question because the stated aim is to evaluate lens performance in habitual soft lens wearers who report substantial digital device use. A participant rating directly captures the wearer’s reported experience rather than an objective measurement of lens performance. Such ratings can represent an outcome of interest in their own right, but they are subjective: responses can reflect individual expectations, experiences, interpretation of the scale, and the circumstances of assessment. The record does not describe any procedures intended to reduce or measure those influences.
As a general statistical point, a median describes the middle of a distribution and is less affected by unusually high or low values than a mean. The full range gives the lowest and highest observed scores, but does not show how scores are distributed between those endpoints. Neither summary indicates how uncertain the median is. A confidence interval or another measure of precision could help characterize uncertainty, but one is not reported in the registry record.
The endpoint definition also specifies the period of digital device use preceding the rating. The registry does not report whether device use was objectively verified, how the rating was collected, or whether participants had complete data at the assessment.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The study question concerns comfort ratings among a defined group of habitual soft lens wearers using digital devices for at least eight hours per day. The registry describes a refit with delefilcon A lenses and a primary assessment at Day 14+2. However, the observed comfort score is not reported in the registry record. Without the median and range, there is no numerical primary outcome to describe, and the direction or magnitude of the participants’ ratings cannot be assessed.
The registry identifies the intended summary as the median with the full range on a 0-to-100 scale. This communicates how the endpoint was defined and how it was intended to be summarized; it does not supply the result. No confidence interval, standard error, test statistic, or p-value for the primary endpoint is reported. Thus, the precision of any estimated comfort level and the compatibility of the data with different possible values cannot be evaluated from the registered results.
The study has no separate comparator arm. Even if a numerical score were available, a single-group result would describe the ratings recorded for participants in this refit group. It would not, by itself, distinguish changes associated with the study lenses from changes over time, expectations, assessment conditions, or other influences. This is a general limitation of interpreting an uncontrolled group, not evidence that any particular influence occurred in this study.
The record reports 41 enrolled participants and notes that 3 discontinued before the study could be completed. It does not state how many participants contributed the primary endpoint or how the discontinued participants’ data were handled. That missing information limits assessment of how representative the recorded outcome might be of everyone enrolled. The record lists three outcome measures but does not provide their numerical results in the information recorded; the other outcomes therefore cannot add quantitative context to the primary measure.
The safety record lists 0 serious adverse events, 0 other adverse events, and 0 deaths among 35 participants at risk in the Refit group. These counts describe the posted safety data and should be read with the stated at-risk group size. They do not supply evidence about events outside the recorded group or establish that no event could occur in other settings.
Overall, the registry record supports a description of the study question, design, and endpoint, but not a conclusion about the observed comfort outcome. The missing numerical endpoint result is central: without it, neither the level of reported comfort nor its variability can be characterized.
9. Statistical Methods Explained
What does the endpoint summary mean?
The registry specifies a median and full range for the primary comfort score. As a general statistical explanation, the median is the central value after observations are ordered. It can be useful when a distribution is skewed or includes unusually high or low ratings, because extreme observations have less influence on the median than on the mean. The range identifies the minimum and maximum recorded values. It gives a sense of the spread from end to end, but it does not reveal whether most participants’ ratings were close together or concentrated near one part of the scale.
The outcome scale runs from 0, worst, to 100, best. A score is an individual rating; a median and range summarize a set of ratings. Neither summary alone gives an interval expressing uncertainty about the population value. A confidence interval is a statistical range intended to convey the precision of an estimate under specified assumptions. No confidence interval for the primary score is reported in the registry record, and the actual median and range are also not reported.
What can a single-group study establish?
The design lists one refit group and no separate comparator. As a general statistical explanation, observations from a single group can describe outcomes in that group, but they do not provide a concurrent control for separating the intervention from other possible influences. An uncontrolled before-and-after comparison would require both baseline and follow-up measurements, and the registry record does not describe a primary baseline comparison. Even when repeated measurements exist, changes over time do not automatically identify a treatment effect because time, expectations, and measurement circumstances may also affect responses.
The record also lists masking as none. This describes the masking entry in the registry; it does not establish what participants or study personnel were told beyond that entry. For a subjective rating, lack of masking can matter in general because expectations may influence reported experience. The registry does not report whether expectations were assessed or how rating procedures were standardized.
How should statistical significance and precision be considered?
A p-value, when reported, summarizes how compatible data are with a specified statistical model and null hypothesis. It is not a measure of the size or importance of an effect, and it does not establish causation. No p-value or inferential test for the primary endpoint is reported in the registry record. In the absence of a comparator and a reported analysis, a significance test should not be inferred from the endpoint definition alone.
Precision is also distinct from the observed score. A confidence interval can show the range of effect or parameter values reasonably compatible with the data under a chosen method. The width depends on factors including the amount of information in the data and their variability. The registry record does not report a confidence interval or enough endpoint statistics to assess precision independently. The full range, if reported, would describe the observed extremes, not uncertainty in the median.
How do planning calculations relate to this study?
The record describes sample-size assumptions for a planning illustration: a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of an observed effect. Those assumptions describe a hypothetical two-arm planning framework, whereas the registered study is single-group and has no randomized comparison. Any sample-size illustration based on those assumptions is a planning exercise, not a description of the actual design or an observed study result. Sample-size calculations are not observed power, and they cannot replace an estimate of the outcome or its uncertainty.
The registry record does not report a sample-size justification for the trial itself, an effect size chosen in advance, or an analysis plan linking a target number of participants to the primary endpoint. The enrollment of 41 is recorded, but enrollment alone does not reveal whether the study had adequate precision for a particular question. That would require a stated target, suitable assumptions, and outcome variability information, none of which is reported as the trial’s own rationale.
What does the analysis record contain?
The record lists three outcome measures and zero analyses. The primary endpoint’s type and summary format are specified, but no numerical result or inferential analysis is reported. General statistical descriptions can explain what a median, range, or confidence interval means; they cannot recover missing study results. The safest interpretation is therefore limited to the registered design and outcome definition, with no claim about the observed level of comfort or a comparative effect.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and identifies subjective comfort after at least eight hours of digital device use as the primary endpoint. The other outcome definitions and their numerical findings are not reported in the registry record. No analysis results are listed. A multiplicity strategy, such as a stated hierarchy among outcomes or an adjustment for testing several outcomes, is not reported in the registry record.
As a general statistical point, assessing several outcomes or conducting several tests can increase the chance of at least one apparently unusual result if each is interpreted independently. Prespecifying a primary outcome and an analysis approach can help readers distinguish confirmatory questions from additional analyses. The registry identifies a primary outcome, but does not report how the three outcomes were to be analyzed together or whether any multiplicity procedure was planned.
The record notes that 3 participants discontinued before the study could be completed. It does not explain reasons for discontinuation, whether their earlier observations were retained, or how missing outcome data were addressed. It also does not report the number of participants with a usable primary endpoint measurement. Missing-data methods can affect the interpretation of an estimate, particularly if participants with missing outcomes differ from those with recorded outcomes. The registry record does not provide enough information to assess that possibility.
An analysis population, such as all enrolled participants or only those completing a specified assessment, is not described in the registry record. Nor is an intention-to-treat approach or another population definition reported. These omissions prevent evaluation of which participants contributed to any planned estimate. Because no numerical primary result or analysis is posted, the effect of missing data and any outcome multiplicity cannot be quantified from 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 |
|---|---|---|---|
| Refit | 0 | 35 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Refit | 0 of 35 |
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 |
|---|---|
| Refit | 0 of 35 |
The safety entry for the Refit group reports 35 participants at risk, 0 serious adverse events, 0 other adverse events, and 0 deaths. No serious adverse event terms are listed. These are the registry’s recorded counts for the stated group and at-risk population.
As a general statistical point, a count of zero means that no events of that category were recorded among the specified participants in the reported data. It does not establish that the underlying risk is zero, and it does not describe events that may not have been captured or reported. The number at risk is the relevant denominator for reading the safety entry; it is distinct from the enrollment figure of 41 and from the 3 participants reported to have discontinued before completion. The registry does not explain the relationship between those counts.
The absence of reported events should not be confused with a complete account of tolerability or with evidence about all possible adverse effects. The registry record does not provide event definitions, collection procedures, follow-up details for participants who discontinued, or a narrative safety analysis. The listed counts can be stated as recorded, but their broader interpretation is limited by the information available in the registry record.
12. What the Result Does, and Does Not, Mean
This study addresses a specific descriptive question: comfort ratings among habitual soft lens wearers who report at least eight hours of digital device use per day after refitting with delefilcon A contact lenses. Its primary endpoint is clearly described as a subjective score at Day 14+2 on a scale from 0, worst, to 100, best. The registry record does not report the observed median or full range, so it does not establish what comfort ratings participants actually gave.
The single-group structure also shapes what the study could show. A set of ratings from the refit group could describe that group’s experience at the assessment. Without a comparator, it could not by itself show how those ratings differ from ratings under another lens or from an alternative condition. This does not make the descriptive question meaningless; it means that conclusions must be confined to the observed group and the information actually reported.
The record reports enrollment of 41 and 3 discontinuations before completion. Because the number contributing the endpoint and the handling of missing observations are not reported, the relationship between the enrolled group and the endpoint summary cannot be assessed. The registry lists safety counts for 35 participants at risk, with 0 serious adverse events, 0 other adverse events, and 0 deaths. Those counts should be interpreted as recorded data, not as proof that risk is absent.
The primary result, uncertainty interval, and numerical results for the other listed outcomes are not reported in the registry record. Therefore, no conclusion about the level, variability, or comparative effect of comfort can be drawn from the posted outcome information. The study record is informative about its purpose, population, intervention, and planned endpoint format, but it does not provide the numerical evidence needed to characterize the outcome.
13. Why This Trial Matters Statistically
The statistical importance of this record lies partly in the distinction between a defined endpoint and a reported result. The registry specifies what was to be rated, when the rating was to be made, the scale anchors, and the summary format. Those details help identify the question the study was designed to address. They are not a substitute for the observed median and range, which are not reported in the registry record.
The single-group design also makes the estimand—the quantity the study aims to describe—important to interpret. Here, the registered question is about subjective performance ratings in a refitted group of habitual soft lens wearers who report substantial digital device use. Without a comparison group, a descriptive account of that group should not be read as a causal comparison between lens options. This distinction is useful for clinical researchers because a clear population and endpoint do not, on their own, create a controlled treatment contrast.
Missing information about endpoint completion and analysis populations matters as well. The record notes 3 discontinuations, yet does not state how many participants posted the primary rating or how missing measurements were handled. That leaves uncertainty about whose responses would contribute to an estimate, even before considering precision or generalizability.
Finally, the safety counts illustrate the need to retain denominators and scope when describing zero events. The posted counts refer to 35 participants at risk in the Refit group. Reading those counts carefully avoids turning a finite set of reported observations into a broader claim about risk. Together, these features make the record a useful example of how trial design, outcome reporting, missingness, and the limits of inference need to be considered alongside an endpoint definition.
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 most direct limitation for interpretation is that the primary endpoint’s observed median and full range are not reported in the registry record. The endpoint can be described, but the actual comfort ratings, their spread, and the precision of any summary cannot be assessed. Numerical results for the other listed outcomes are also not reported.
The study is single-group, with no separate comparator listed, and masking is recorded as none. Thus, any descriptive ratings would not provide a randomized comparison. Because the endpoint is subjective, the lack of masking is relevant as a possible source of influence in general, but the record does not establish that expectations altered responses in this study.
The registry reports 41 enrolled participants and 3 who discontinued before completion. It does not report the number contributing the primary endpoint, reasons for discontinuation, missing-data handling, or analysis population. These omissions leave the completeness of outcome follow-up and the role of missing observations unclear. The safety entry uses 35 participants at risk; the relationship between that number and the enrollment and discontinuation counts is not explained.
Other study details that could affect interpretation are not reported in the registry record, including eligibility criteria beyond the described population, the method of collecting comfort ratings, verification of reported device-use duration, and a trial-specific statistical analysis plan. The record lists three outcome measures and zero analyses, and it does not report a sample-size justification or interim-analysis plan. These are reporting limitations; the registry information does not support assumptions about what procedures may or may not have occurred outside the recorded details.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Performance of DAILIES TOTAL1 Daily Disposable Contact Lenses in Habitual Soft Lens Wearers Who Report Substantial Digital Device Use — NCT06308666.
- Registry record last updated 2025-10-31; status last verified 2024-12.
- Results first posted 2025-10-31.
- 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
NCT06308666 is a completed, single-group study sponsored by the University of Waterloo. It enrolled 41 habitual soft lens wearers with myopia who reported substantial digital device use and evaluated delefilcon A contact lenses after refitting. The study began on 2024-03-18 and reached primary completion on 2024-10-23.
The primary endpoint was a subjective overall comfort rating after at least eight hours of digital device use at Day 14+2, on a scale from 0, worst, to 100, best. The intended summary was the median and full range, but the observed result is not reported in the registry record. Three participants discontinued before completion. The safety record lists 35 participants at risk, 0 serious adverse events, 0 other adverse events, and 0 deaths. No separate comparator is listed, and the registry reports zero analyses.