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 Evaluation of Two Daily Disposable Contact Lenses. (NCT01300065), a randomized na study. The primary outcome is Percentage of Eyes With > Grade 2 Slit Lamp Findings.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01300065 |
| Phase | NA |
| Condition | Myopia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 441 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Bausch & Lomb Incorporated |
| Results posted | Yes |
2. Clinical Question
Population
Participants with myopia who used technology devices for an average of 4 hours per day over a week's time, on at least 4 days each week. The study enrolled 441 participants. The registry record does not provide further eligibility details or a more specific description of the study population.
Intervention
An experimental SofLens daily disposable contact lens packaged in an investigational storage solution. The study evaluated product performance, with comfort among the stated interests.
Comparator
A marketed SofLens daily disposable contact lens packaged with 0.5% poloxamine in buffered saline solution.
Primary question
At 2 weeks, what proportion of assessed eyes in each arm had any slit-lamp abnormality graded above 2? Findings assessed included epithelial edema, epithelial microcysts, corneal staining, limbal and bulbar injections, upper lid tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates. The registry record posts arm values of 0.0 but states that a two-arm comparison was not estimable for this count outcome. It therefore does not establish a comparative effect for the primary endpoint.
The objective described in the registry record also refers to comfort during technology-device use. The primary endpoint reported in the results, however, is based on slit-lamp findings, not a comfort rating. A secondary outcome is named as the Initial Lens Performance Survey, but its results are not reported in the registry record. The central statistical question is consequently narrower than the study's overall stated objective: it concerns the occurrence of higher-grade eye findings at the reported assessment time, and the posted information does not give an inferential estimate comparing the lens groups.
3. Trial Design
The registry record describes a randomized, double-masked, parallel-group study of two daily disposable contact lenses. The listed phase is not applicable. The study status is completed, and the recorded enrollment is 441. The start and primary completion are recorded as 2011-01 and 2011-03, respectively. The sponsor is Bausch & Lomb Incorporated.
Participants were assigned to the experimental SofLens product or the marketed SofLens product. The experimental product was packaged in an investigational storage solution; the comparator was packaged with 0.5% poloxamine in buffered saline solution. Randomization is intended to balance, on average, participant characteristics that could affect outcomes, while masking is intended to reduce the influence of expectations on care, assessments, or reporting. These are general purposes of the design features; the registry record does not describe how randomization was generated, how assignments were concealed, or which people were masked.
The parallel design means the listed arms represent separate groups rather than a crossover comparison. The registry record does not report the allocation ratio or the detailed sequence of study procedures. Its primary endpoint is assessed at 2 weeks, but the record does not describe other visit timing or follow-up beyond the information attached to the listed outcomes. It also does not report a sample-size justification or a detailed protocol for handling both eyes when eye-level assessments are made.
The arm entries list 219 participants for the experimental product and 217 for the marketed product. For the primary outcome, the registry record separately says that 438 eyes in the test group and 434 eyes in the control group were assessed. These are different units: the arm entries refer to participants, while the primary outcome is expressed in eyes. The record does not explain the relationship between participant counts and assessed-eye counts, or whether all randomized participants contributed to the primary assessment.
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 | Experimental- Soflens | Marketed - Soflens |
|---|---|---|
| STARTED | 221 | 220 |
| COMPLETED | 215 | 217 |
| NOT COMPLETED | 6 | 3 |
Analysis population for the primary outcome, as defined in the registry: There were 438 eyes in the test group and 434 eyes in the control group that were assessed for this outcome measure.
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: Eligible, dispensed participants were summarized.
| Characteristic | Unit | Experimental- Soflens | Marketed - Soflens | Total |
|---|---|---|---|---|
| Participants analysed | 215 | 216 | 431 | |
| Age, Continuous | years | 27.1 (15 to 40) | 26.6 (15 to 50) | 26.8 (15 to 40) |
| Sex: Female, Male: Female | Participants | 140 | 153 | 293 |
| Sex: Female, Male: Male | Participants | 75 | 63 | 138 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Eyes With > Grade 2 Slit Lamp Findings, measured over 2 weeks.
| Element | Registry entry |
|---|---|
| Result type | Count Of Units |
| Measure of spread | not applicable |
| Unit | eyes |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “Percentage of Eyes With > Grade 2 Slit Lamp Findings.” It concerns whether an assessed eye had any listed slit-lamp abnormality with a severity grade above 2 at 2 weeks. The scale runs from 0, meaning no finding, to 4, meaning a severe finding. The assessed abnormalities include epithelial edema, epithelial microcysts, corneal staining, limbal and bulbar injections, upper lid tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates. The endpoint counts an eye if any of the abnormalities meets the stated grade threshold.
A threshold-based endpoint can focus attention on findings above a specified severity level rather than treating every grade as equivalent. As a general statistical point, turning several graded observations into a single yes-or-no outcome may make the result easier to interpret, but it also discards detail about which finding occurred and its precise grade. The registry record does not report separate results for the individual abnormalities or the full distribution of grades.
The outcome is defined at the eye level, and the registry record reports assessed-eye counts for each group. The posted arm values are 0.0 in both arms. However, the record also identifies the two-arm comparison as not estimable for this count outcome. It therefore does not support an interpretation of the arm values as a quantified comparative effect, nor does it provide an uncertainty interval for that effect.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome has arm values of 0.0 for the experimental SofLens and the marketed SofLens groups. The registry record identifies the endpoint as a count-type outcome and explicitly indicates that a two-arm comparison was not estimable. These details should be read together: the arm entries alone do not provide an estimated treatment contrast, its uncertainty, or a test of the difference between groups.
The endpoint concerns eyes with any slit-lamp finding above grade 2 at 2 weeks. The registry record says that 438 eyes in the test group and 434 eyes in the control group were assessed. The analysis entries list 219 participants in the experimental arm and 217 in the marketed arm. Since the outcome unit is eyes and the group entries are participants, the denominators should not be treated as interchangeable. The record does not explain how eye-level observations were related to participant-level assignment or how the eye counts were used in analysis.
No confidence interval, p-value, effect estimate, or analysis method for a between-group comparison is reported in the registry record. As a general statistical explanation, an estimate describes the observed contrast, while a confidence interval conveys the range of values reasonably compatible with the data under the analysis assumptions. A p-value addresses compatibility with a specified null model; it is not a measure of the size or clinical importance of an effect. Since these inferential quantities are not reported and the registry marks the comparison as not estimable, the posted results do not permit conclusions about the precision or statistical significance of a difference between products.
The primary endpoint is only one part of the study objective. The brief summary emphasizes comfort during technology-device use, while the posted primary outcome is a slit-lamp finding. The Initial Lens Performance Survey is listed as a secondary outcome, but its result is not reported in the registry record. The record lists 2 outcome measures and 0 analyses. It does not give results for the comfort objective in the information available for this interpretation.
Zero-valued arm entries should not be expanded into a claim about every participant, every eye, or every possible adverse effect. They describe the values posted for this endpoint, in the context of a comparison that the registry says could not be estimated. Nor do these entries address outcomes not reported, different follow-up times, or other populations. The appropriate statistical reading is therefore limited: the registry record posts zero values for the primary outcome in both arms, but does not report an estimable comparative result or the inferential details needed to quantify how precisely the groups were compared.
9. Statistical Methods Explained
The design is randomized, double-masked, and parallel-group. In general, random assignment helps make groups comparable with respect to measured and unmeasured characteristics on average, although it does not guarantee exact balance in any particular trial. Masking can limit bias from knowledge of assignment. The registry record does not report the randomization procedure, the concealment mechanism, who was masked, or whether masking was assessed. These omissions prevent a detailed evaluation of how those design safeguards were implemented.
What does the endpoint count?
The primary outcome defines an eye as meeting the endpoint if any assessed slit-lamp finding is graded above 2. The underlying grades run from 0 to 4. This creates a binary status for each eye: meeting the threshold or not meeting it. The title describes a percentage, and the unit is eyes, while the endpoint's parameter is identified as a count of units. The registry record does not give a more detailed derivation of the posted 0.0 arm values, so the comparison cannot be reconstructed from the entry alone.
In general, a percentage for a binary outcome is interpreted relative to a denominator: the number of eyes meeting the criterion divided by the number of eyes assessed. A comparison may then be expressed using a difference, ratio, or other effect measure. Those are general approaches, not estimates reported for this trial. No such comparative effect or uncertainty interval appears in the registry record, and the record specifically marks the two-arm comparison as not estimable.
Why does the unit of analysis matter?
The primary outcome is measured in eyes, but lens assignment occurs through participant groups. As a general statistical point, when both eyes from one participant contribute, the two observations may be more alike than observations from different participants. Treating correlated eyes as if they were fully independent can make uncertainty estimates too small. Analyses can account for this structure using methods suited to clustered or paired observations, depending on the design and data. The registry record does not say whether both eyes contributed for each participant, or how any within-participant dependence was handled. It therefore does not allow assessment of this issue for the posted endpoint.
The record gives 438 assessed eyes in the test group and 434 in the control group, and separately lists arm entries of 219 and 217 participants. These counts should remain distinct. A statistical analysis must use the appropriate unit and account for the relationship between eyes and participants; simply comparing the raw numbers without knowing the analysis approach would not establish a valid treatment contrast.
What can inferential statistics add?
In general, an effect estimate gives a numerical description of a contrast between groups. A confidence interval expresses uncertainty around that estimate under the chosen model and assumptions. A hypothesis test can assess how compatible the observed data are with a null hypothesis, but its p-value does not tell readers the probability that the null hypothesis is true and does not by itself convey practical importance. These concepts are relevant to interpreting a randomized comparison, but the registry record does not report an effect estimate, confidence interval, p-value, or inferential model for the primary endpoint.
The record lists 0 analyses and notes that a two-arm comparison was not estimable for this count-type endpoint. That status matters: it signals that an inferential comparison is not available in the posted record. The arm-level entries do not substitute for a contrast with uncertainty, and a reader should not infer a test result from the matching values alone.
How should planning calculations be read?
As a general matter, sample-size calculations describe the number of participants needed under specified assumptions about the outcome, effect to detect, significance level, power, allocation, and analysis. They are planning illustrations, not observed power and not evidence that a trial did or did not detect an effect. The registry record's stated illustration assumptions use a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. For time-to-event outcomes, the stated convention is to report total events; for other outcomes, it is participants per arm. These assumptions do not replace a trial's prospective design justification, which is not reported in the registry record.
For a count outcome, the distribution and frequency of observations can influence the suitability of a statistical model. As a general explanation, over-dispersion occurs when variability exceeds what a simple model assumes; ignoring it can lead to misleading uncertainty estimates. The registry record does not report a model, a dispersion estimate, or an adjustment for this issue. Because no comparative analysis is posted for the primary endpoint, readers cannot determine which method was used or whether its assumptions were assessed.
The key methodological distinction is between describing the entries and drawing an inferential conclusion. The registry records the study design, eye-level outcome definition, assessment counts, and arm-level values. It does not report enough analysis detail to establish how those observations were converted into a comparison or how uncertainty was quantified. Interpretation should therefore remain descriptive and bounded by the registry's explicit statement that the two-arm comparison was not estimable.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists 2 outcome measures, including the primary slit-lamp endpoint and the secondary Initial Lens Performance Survey. It lists 0 analyses. The secondary outcome is named, but its results are not reported in the registry record. The record does not identify additional analyses or explain whether outcomes were tested in a prespecified order.
As a general statistical point, testing multiple outcomes or multiple versions of an outcome can increase the chance of finding an apparently notable result by chance. Researchers may address this through a prespecified hierarchy, adjustment procedures, or careful interpretation of exploratory findings. The registry record does not report whether any multiplicity plan was used, so no claim can be made about adjustment or control of the overall error rate.
The record also does not describe missing-data handling, exclusions from the primary analysis, or the analysis population. It does not say whether the primary analysis followed randomized assignment, included all randomized participants, or used another population definition. The enrollment and arm entries do not establish which participants contributed to each analysis. The eye-assessment counts are reported, but the record does not explain missing assessments or the relationship between assessed eyes and participants.
These omissions matter because missing outcomes and selective analysis can affect the interpretation of a group comparison. In general, an analysis restricted to observations with recorded outcomes may be biased if missingness is related to the outcome or group. The registry record does not provide enough information to evaluate that possibility or to determine whether the posted primary values reflect all intended observations.
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 |
|---|---|---|---|
| Experimental- Soflens | 0 | 221 | 0.0% |
| Marketed - Soflens | 0 | 220 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Experimental- Soflens | 0 of 221 |
| Marketed - Soflens | 0 of 220 |
The registry safety entries report no serious adverse events for either group: the experimental SofLens group has 0 serious events among 221 at risk, and the marketed SofLens group has 0 among 220 at risk. The entries also report 0 other adverse events among 221 at risk in the experimental group and 0 among 220 at risk in the marketed group. These safety denominators differ from the participant counts listed for the primary arm entries and should be kept distinct.
These figures describe the events recorded in the registry for the stated groups. They do not provide event rates computed here, and they do not establish that no safety events of any kind occurred outside the categories or reporting period represented. The death values are not reported in the registry record. No serious adverse-event terms are listed.
As a general statistical point, an observed count of zero does not prove that the underlying event risk is zero. The precision of a safety estimate depends on the number at risk, the follow-up period, event definitions, and completeness of reporting. The registry record does not provide sufficient detail about safety surveillance or follow-up to assess those aspects fully. These entries should therefore be read as registry-reported counts, not as a complete safety characterization or a comparative safety analysis.
12. What the Result Does, and Does Not, Mean
The record documents a randomized, double-masked comparison of an experimental and a marketed daily disposable SofLens lens, with the primary outcome focused on eyes with slit-lamp findings above grade 2 at 2 weeks. It posts arm values of 0.0 for that outcome and reports the numbers of eyes assessed in each group. It also explicitly states that a two-arm comparison was not estimable.
That combination supports a limited descriptive statement about what the registry reports, but not a quantified conclusion about a difference between products. There is no reported treatment contrast, confidence interval, p-value, or model for the primary endpoint. Without an estimable comparison and a measure of uncertainty, the size and precision of any between-group effect cannot be established from the registry record.
The study's stated objective includes comfort during use of technology devices, but the primary endpoint reported is a slit-lamp measure. The Initial Lens Performance Survey is listed as a secondary outcome, and its results are not reported in the registry record. Accordingly, the posted primary outcome does not answer every aspect of the stated objective. Nor does it describe performance beyond the specified eye findings and assessment time.
The registry record also does not provide the analysis population, missing-data approach, method for handling eye-level observations, or detailed statistical plan. Those omissions restrict evaluation of how the results were derived and how robust a comparison might be. The safety entries report zero serious and other adverse events in each group among the stated at-risk counts, but deaths are not reported and the record does not provide a full safety analysis.
As a general principle, a non-estimable comparison is not evidence of equivalence, and matching arm-level values do not by themselves demonstrate that groups are equivalent. Equivalence or noninferiority requires a prespecified framework, a suitable margin, and an analysis that addresses uncertainty. None of those details are reported for this endpoint. The registry result should therefore be read as an incomplete comparative record: it identifies the endpoint and group values, but does not support a definitive comparative interpretation.
13. Why This Trial Matters Statistically
This trial illustrates why the outcome unit and the randomized unit both matter in clinical statistics. Participants were assigned to lens groups, while the primary outcome is defined for eyes. The record gives participant counts for the arms and separate assessed-eye counts. Those quantities answer different questions and cannot be substituted for one another. A sound analysis must make clear how eye observations relate to participant assignment and how any dependence between eyes is handled.
It also demonstrates the difference between arm-level descriptions and comparative inference. Matching posted values may look straightforward, but a treatment comparison requires a defined effect measure and, for interpretation, information about uncertainty. The registry record marks the comparison as not estimable and does not provide a confidence interval, p-value, or analysis method. That limitation is more informative than treating the arm entries as if they were a complete statistical result.
The endpoint combines several types of slit-lamp findings into a threshold outcome. This can make the target clinically interpretable as a higher-grade finding, while leaving unanswered which specific abnormality occurred or how grades were distributed. The registry record does not report these details separately. This shows how endpoint construction determines which aspects of a study's observations can be understood from its results.
Finally, the stated study objective includes comfort, while the primary outcome reported is an eye examination finding. The named secondary survey could address a different dimension of product performance, but its result is not reported in the registry record. Comparing the stated objective with the available outcome results is important when deciding what a trial's posted statistics do and do not address. The record is useful for identifying design and outcome definitions, but its limited analysis reporting constrains the conclusions that can be drawn.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The registry record does not report a numerical comparison for the primary endpoint, and it explicitly identifies the two-arm comparison as not estimable. Although arm-level values are posted as 0.0, there is no effect estimate or uncertainty interval to show how precisely the groups were compared. This is the central limitation for interpreting the primary result.
The unit of the endpoint is eyes, while the study groups are described in participants. The record reports 438 assessed eyes in the test group and 434 in the control group, alongside participant arm entries of 219 and 217. It does not explain whether both eyes were assessed for each participant, how missing eye assessments were handled, or whether statistical methods accounted for dependence between eyes from the same participant.
Other important analysis details are not reported in the registry record, including the randomization procedure, allocation concealment, who was masked, analysis population, missing-data method, and statistical model. The record does not give a sample-size justification or explain how the planned enrollment related to the primary endpoint. It lists the Initial Lens Performance Survey as a secondary outcome but does not report its result. The available information therefore does not allow a full assessment of outcome reporting or analysis choices.
Follow-up for the primary endpoint is stated as 2 weeks, and the registry record does not describe longer-term outcome assessment. It does not report separate results for the individual slit-lamp abnormalities or the full grade distribution. Safety reporting is also limited: event counts are listed, but deaths are not reported and details of surveillance and follow-up are absent. These limitations narrow the interpretation to the outcomes and counts recorded, rather than a complete account of product performance or safety.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Evaluation of Two Daily Disposable Contact Lenses. — NCT01300065.
- Registry record last updated 2020-10-06; status last verified 2020-09.
- Results first posted 2020-10-06.
- 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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Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes a completed, randomized, double-masked, parallel-group study of two daily disposable SofLens contact lenses in participants with myopia. Recorded enrollment is 441. The experimental lens was packaged in an investigational storage solution; the marketed comparator was packaged with 0.5% poloxamine in buffered saline solution.
The primary outcome is the percentage of eyes with any slit-lamp finding above grade 2 at 2 weeks. The posted arm values are 0.0, with 438 eyes assessed in the test group and 434 in the control group. The registry states that a two-arm comparison was not estimable. It lists the Initial Lens Performance Survey as a secondary outcome, but its result is not reported in the registry record.
The registry lists 0 analyses and does not report an inferential estimate, uncertainty interval, analysis population, or missing-data method. Safety entries report zero serious and other adverse events in each group for the stated at-risk counts; deaths are not reported. Overall, the record supplies design and endpoint descriptions but does not provide an estimable comparative result for the primary outcome.