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 Study of A New Contact Lens Cleaning and Disinfecting Solution (NCT01318577), a randomized na study. The primary outcome is Percentage of Eyes With > Grade 2 Slit Lamp Findings.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01318577 |
| Phase | NA |
| Condition | Vision Disorders |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 444 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Bausch & Lomb Incorporated |
| Results posted | Yes |
2. Clinical Question
The central question is whether the investigational hydrogen peroxide cleaning and disinfecting solution and Clear Care Solution differ in the reported occurrence of slit lamp findings graded above 2 after approximately three months of use. Both solutions are described as hydrogen peroxide systems for cleaning, protein removal, disinfecting, and storing contact lenses.
Population
Contact lens wearers with dispensed eyes having nonmissing slit lamp scores. The registry reports 442 such eyes in the investigational group and 438 in the Clear Care group. The study enrolled 444 participants.
Intervention
The investigational cleaning and disinfecting solution, described as a hydrogen peroxide system for cleaning, protein removal, disinfecting, and storing contact lenses.
Comparator
Clear Care Solution, also described as a hydrogen peroxide system for cleaning, protein removal, disinfecting, and storing contact lenses.
Primary question
What occurrence of eye findings graded above 2 was recorded for each solution at 3 months, and how precisely can any difference between groups be estimated?
The outcome description lists several examination findings, including epithelial edema, epithelial microcysts, corneal staining, limbal and bulbar injections, upper lid tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates. Each finding was graded for severity on a scale from 0, meaning no finding, to 4, meaning severe finding. The recorded outcome concerns any finding above grade 2 across those abnormalities.
The registry lists outcome values of 4.0 for the investigational group and 0.0 for the Clear Care group. Although the outcome title refers to a percentage, the posted results identify the measure as a count of units. No comparative effect estimate or uncertainty interval is reported, so the values alone do not establish the magnitude or precision of a between-group difference.
3. Trial Design
This was a randomized, double-masked, parallel-group trial. Participants were assigned to the investigational solution or Clear Care Solution, with each group using its assigned product. In a parallel design, participants remain in their assigned groups rather than switching between treatments. Random allocation is intended, in general, to make treatment groups comparable at the start with respect to both measured and unmeasured characteristics. Double masking generally means that two categories of people involved in the trial are kept unaware of assignment, but the registry record does not specify who was masked or how masking was maintained.
The recorded enrollment was 444. The posted arm sizes are 221.0 for the investigational solution and 218.0 for Clear Care Solution. The primary outcome population is described in terms of eyes with nonmissing scores: 442 eyes in the investigational group and 438 in the Clear Care group. These are different units of description—participants in the arm listings and eyes in the outcome population—and should not be treated as interchangeable denominators.
The study objective was to evaluate safety and efficacy when contact lens wearers used the assigned solution to clean and disinfect their lenses for approximately three months. The primary outcome timeframe is listed as 3 months. The registry gives a start date of 2010-11, a primary completion date of 2011-04, and a completed status. It identifies the sponsor as Bausch & Lomb Incorporated and lists the condition as Vision Disorders.
The phase is recorded as NA, and both interventions are classified as devices. The registry record does not report the randomization method, allocation concealment procedures, masking details, site structure, eligibility criteria, or a sample-size justification. It also does not describe whether participants were followed for the same duration within the approximate three-month period.
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 | Investigational Solution | Clear Care Solution |
|---|---|---|
| STARTED | 224 | 220 |
| COMPLETED | 211 | 212 |
| NOT COMPLETED | 13 | 8 |
Analysis population for the primary outcome, as defined in the registry: There were 442 dispensed eyes with nonmissing scores in the investigational group and 438 dispensed eyes with nonmissing scores in the Clear Care group.
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: Demographics are reported for all eligible, dispensed subjects; 222 in the investigational group and 218 in the Clear Care group.
| Characteristic | Unit | Investigational Solution | Clear Care Solution | Total |
|---|---|---|---|---|
| Participants analysed | 222 | 218 | 440 | |
| Age, Continuous | years | 35.4 (18 to 68) | 35.3 (18 to 63) | 35.4 (18 to 68) |
| Sex: Female, Male: Female | Participants | 160 | 163 | 323 |
| Sex: Female, Male: Male | Participants | 62 | 55 | 117 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Eyes With > Grade 2 Slit Lamp Findings, measured over 3 months.
| 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 outcome concerns the percentage of eyes with any slit lamp finding graded above 2 at 3 months. Slit lamp examinations assess visible eye findings; the registry lists epithelial edema, epithelial microcysts, corneal staining, limbal and bulbar injections, upper lid tarsal conjunctival abnormalities, corneal neovascularization, and corneal infiltrates. Severity was scored from 0, no finding, to 4, severe finding. The outcome description indicates that the threshold applies to any listed abnormality, rather than to a single finding alone.
A threshold-based outcome can make a clinical examination scale easier to interpret by distinguishing findings that cross a defined severity cutoff from those that do not. In general, however, reducing a graded scale to a threshold also loses information about the exact grade and which specific finding occurred. The registry record does not report separate results for the individual abnormalities or the distribution of severity grades.
There is an important reporting ambiguity. The outcome title calls the measure a percentage, while the results are designated as counts of units and the arm values are 4.0 and 0.0. The record does not clarify whether those values are percentages or counts, nor does it provide a percentage estimate with a denominator. It reports 442 eyes with nonmissing scores in the investigational group and 438 in the Clear Care group, but does not reconcile those eye counts with the values' count-of-units label. Consequently, the outcome can be described from the registry, but a percentage or comparative effect should not be reconstructed from the posted values.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome values are 4.0 for the investigational solution and 0.0 for Clear Care Solution. These are the values recorded for the two arms; the registry does not report a statistical comparison between them. The outcome title refers to the percentage of eyes with findings above grade 2, but the measure is identified in the results as a count of units. Since the record does not resolve that difference in labeling, the values should be read as posted rather than converted into percentages or another effect measure.
The registry records outcome scores for 442 eyes in the investigational group and 438 eyes in the Clear Care group. These eye counts describe the population with nonmissing scores; they are not the arm sizes listed in the outcome results, which are 221.0 and 218.0. The record does not explain the relation between the participant and eye denominators or specify how missing scores were handled. In particular, it does not report why some eyes lacked nonmissing scores or whether any analysis accounted for paired eyes from the same participant.
No two-arm estimate, confidence interval, hypothesis test, or p-value is reported. As a result, the registry does not quantify the estimated difference or its statistical uncertainty. A confidence interval, in general, describes a range of values compatible with an estimate under the assumptions of the analysis; without an estimate and interval, the precision of a group comparison cannot be assessed from these results. The record also gives no analysis method for the endpoint, so the assumptions behind any potential comparison cannot be evaluated.
The registry lists one primary outcome measure and no posted secondary outcomes. That listing describes what is present in the record, not necessarily every outcome assessed in the trial. The record does not report an analysis population definition, a prespecified statistical plan, or a multiplicity strategy. It is therefore not possible to determine from the registry whether the posted arm values represent a prespecified analysis or how any decisions about multiple outcomes or analyses were managed.
The safety record reports zero serious adverse events among 224 participants at risk in the investigational group and zero among 220 at risk in the Clear Care group. These counts are separate from the primary eye finding outcome. The record does not report deaths as a numeric result, and it does not provide detailed safety-analysis methods or event timing. Neither the primary outcome entries nor the serious adverse event entries alone provide a complete assessment of the comparative safety and efficacy objectives.
The most defensible interpretation is therefore descriptive: the registry records the stated arm values, eye-score populations, and serious adverse event counts, but it does not supply the comparative statistical analysis needed to quantify a treatment-group difference or its precision.
9. Statistical Methods Explained
The registry identifies the study as randomized, double-masked, and parallel-group. Those design features describe how assignment and observation were intended to be organized, but they do not tell readers which statistical procedures were applied to the outcome. The record lists zero analyses. It does not report a statistical model, an effect estimate, an uncertainty interval, a hypothesis test, or a p-value for the primary outcome.
What does random allocation contribute?
In general, random allocation uses chance to assign participants to groups. If implemented as planned, it can reduce systematic differences between groups at baseline, including differences that are not measured. It does not guarantee that the groups will be identical, and it does not by itself address missing observations, measurement error, or the choice of statistical analysis. The registry does not describe the sequence-generation procedure, allocation concealment, or checks of baseline comparability, so those implementation details cannot be evaluated from the record.
What does double masking mean?
In general, masking can reduce the risk that knowledge of assigned treatment influences participant behavior, care, outcome assessment, or reporting. The term double-masked indicates that two categories of people were intended to be unaware of assignment. The record does not identify those categories or explain how masking was maintained. It also does not report whether masking was assessed or whether any departures from masking occurred.
How should the endpoint values be read?
The listed outcome is eye-based and uses a threshold across several slit lamp abnormalities. A count outcome records how many units meet a definition; a percentage expresses a count relative to a denominator. The registry title uses percentage language, whereas the result is designated as a count of units. This mismatch matters because an absolute count and a percentage answer different questions, especially when denominators vary. The eye populations are reported, but the record does not identify a percentage result or explain how the values 4.0 and 0.0 relate to those populations. No conversion is warranted without that clarification.
In general, analysis of eye-level outcomes may need to account for the fact that two eyes can belong to one participant. Outcomes from the same person may be correlated, so treating every eye as independent can understate uncertainty if that correlation is ignored. The registry does not say whether both eyes were included for every participant in the analysis or whether any method addressed within-participant dependence. This is a general statistical consideration, not a claim about the analysis used in this trial.
What can an uncertainty interval tell a reader?
In general, a confidence interval pairs an estimated effect with a range that reflects sampling uncertainty under the analysis assumptions. A narrow interval indicates greater precision than a wide interval, while an interval that includes values representing no difference can indicate that the data are compatible with a range of possible effects. These interpretations depend on the analysis and the interval's construction. No interval is reported for this outcome, so neither the range of plausible differences nor the precision of an estimated comparison is available.
For counts, general methods may use a probability model suited to the way events arise. If count variation is greater than a chosen model expects, over-dispersion can make standard errors too small unless the method accommodates that extra variation. This is a general issue; the registry does not provide enough information about the endpoint values or the analysis to establish whether over-dispersion was relevant or handled.
What does the record say about planning and power?
The registry record does not report a sample-size justification or the assumptions used to choose enrollment. A planning calculation based on an observed effect is not the same as the trial's original design justification, and it is not observed power. In general, power is a design-stage probability tied to a specified effect, variability, significance level, and analysis. It does not measure the probability that a result is true after the data have been observed. No trial-specific power calculation or design assumptions are reported in the registry record.
The exact statistical plan is not reported in the registry record. This includes the model or test for the primary endpoint, whether adjustment for covariates was planned, the handling of incomplete scores, and the treatment of multiple outcomes or analyses. Without those details and a posted comparative estimate, readers can describe the arm values but cannot independently assess how an inferential result would have been produced.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists one primary outcome measure and no posted secondary outcomes. This does not establish that the study assessed only one outcome or carried out only one analysis. The record reports zero analyses and does not give a statistical analysis plan, so it is not possible to determine which endpoints or subgroup comparisons were prespecified, whether interim analyses occurred, or whether any multiplicity adjustment was used. Those details are not reported in the registry record.
Multiplicity arises, in general, when several hypotheses or outcomes are tested: the chance of a false-positive finding across the set can be higher than for a single test. Methods such as prespecifying a primary endpoint or adjusting inference can address that issue, but the appropriate approach depends on the study plan. No such approach is described for this trial. The single listed primary outcome should therefore not be taken as evidence that multiplicity was absent.
The endpoint population description states that 442 investigational-group eyes and 438 Clear Care-group eyes had nonmissing scores. The record does not report why scores were missing, whether missingness differed by group, or how incomplete eye-level data were handled. It does not identify an intention-to-treat, per-protocol, or other analysis population. The arm sizes are given separately as 221.0 and 218.0, and the registry does not explain how participants without scored eyes were addressed in the outcome analysis.
In general, missing-data methods rely on assumptions about why observations are absent. When those assumptions are not stated, readers cannot judge whether a complete-case analysis or another approach might introduce bias. The registry record does not report sensitivity analyses or imputation procedures. The available denominator information is useful for describing recorded scores, but it does not resolve the missing-data mechanism or its possible influence on the comparison.
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 |
|---|---|---|---|
| Investigational Solution | 0 | 224 | 0.0% |
| Clear Care Solution | 0 | 220 | 0.0% |
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 |
|---|---|
| Investigational Solution | 0 of 224 |
| Clear Care Solution | 0 of 220 |
The serious adverse event entries report zero affected participants in each group: 0 of 224 at risk in the investigational group and 0 of 220 at risk in the Clear Care group. These are the posted serious adverse event counts and the corresponding numbers listed as at risk. The registry also records zero other adverse events in those groups, but it does not provide further event-level detail in the information reported.
A zero count means that no serious adverse event was recorded in the relevant group in this registry entry. In general, it does not establish that the underlying risk is zero; uncommon events may not occur in a study of limited size or duration. A comparative safety assessment also depends on follow-up, event definitions, completeness of reporting, and a statistical analysis. The registry does not report a comparative safety estimate or uncertainty interval.
Deaths are not reported as numeric results in the registry record. That absence should not be read as a reported zero. The record also does not describe serious-event definitions, collection procedures, timing, or adjudication. These figures therefore provide a limited count-based safety description, rather than a complete account of all safety evidence or a quantified comparison between solutions.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized, double-masked, parallel-group study compared an investigational contact lens cleaning and disinfecting solution with Clear Care Solution, with a primary outcome focused on slit lamp findings above grade 2 at 3 months. It records arm values of 4.0 and 0.0, respectively, and identifies eye populations with nonmissing scores. It also records zero serious adverse events in each group among the stated numbers at risk.
Those entries do not provide a complete statistical answer to the comparative question. The outcome title calls the measure a percentage, but the result is labeled as a count of units. The registry does not explain the mismatch or report a percentage estimate. It also does not provide a between-group effect estimate, confidence interval, p-value, or analysis method. The difference in the posted arm values therefore cannot be translated into a quantified treatment effect or a statement about statistical uncertainty.
In general, a result from one trial is interpreted in light of its design, measurement, follow-up, missing data, and analysis. Here, details about eligibility criteria, masking procedures, outcome analysis, missing-score handling, and the statistical plan are not reported in the registry record. The approximate three-month use period and listed 3-month outcome timeframe describe the intended observation period, but the record does not give further detail on exposure or follow-up.
The safety entries likewise have a limited scope. Zero recorded serious adverse events in both groups does not by itself quantify how similar the groups were in risk, and deaths are not reported numerically. The record does not provide enough detail to assess the completeness or timing of safety surveillance.
Accordingly, these registry results support a careful description of what was recorded, not a conclusion that either solution is more effective or safer. The posted figures do not settle the comparative question, and the missing inferential and methodological information limits how precisely the results can be interpreted.
13. Why This Trial Matters Statistically
This trial illustrates why endpoint labels, measurement units, and denominators need to align. The primary outcome title describes a percentage of eyes, while the posted results are identified as counts of units. Because the record does not resolve that distinction, readers cannot confidently interpret the arm values as proportions or compare them using the eye counts. Clear reporting of the numerator, denominator, and outcome scale is essential for a reproducible interpretation.
It also highlights the distinction between participant-level and eye-level information. The arm listings give participant counts, while the primary outcome population is described using eyes with nonmissing scores. In general, multiple observations from one participant may be statistically dependent. A suitable analysis may need to account for that dependence, and a transparent report should state the unit of analysis and the method used. The registry does not report those methods.
Finally, the entry demonstrates that trial design labels do not replace analysis reporting. Randomization and masking are important design features, but they do not reveal the effect estimate, its uncertainty, or the handling of incomplete observations. With no posted comparative analysis, the observed arm values remain descriptive and cannot show how precisely a group difference is estimated. The serious adverse event counts are also descriptive, with no comparative safety estimate or numeric death result.
For clinical researchers and biostatisticians, the record is a useful reminder that an interpretable result requires more than an outcome name and arm values. The endpoint definition, analysis population, statistical method, uncertainty estimate, missing-data approach, and multiplicity strategy all help readers determine what a result means. When those details are absent or the measurement label is ambiguous, the appropriate conclusion is limited to what the registry explicitly 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 most immediate limitation is the inconsistency between the primary outcome title, which refers to a percentage, and the posted result classification as a count of units. The registry gives arm values of 4.0 and 0.0 but does not explain their scale or provide percentages. Although it reports 442 eyes with nonmissing investigational-group scores and 438 with nonmissing Clear Care scores, it does not reconcile those denominators with the outcome values.
The record gives no two-arm statistical estimate, confidence interval, p-value, or endpoint analysis method. It also does not state whether the analysis unit was the eye or participant, or whether any analysis accounted for dependence between eyes of the same participant. The participant arm sizes and eye-score populations are reported separately, without a description of how they map to one another.
Information needed to assess missing data is not reported: reasons for missing scores, the missingness pattern, the analysis population, and any imputation or sensitivity analyses are absent. The registry also does not report eligibility criteria, details of randomization or masking, a sample-size justification, or a statistical analysis plan. Although the outcome timeframe is 3 months and use is described as approximately three months, further detail about follow-up is not provided.
For safety, serious adverse event counts are available, but event definitions, timing, collection methods, and a comparative analysis are not reported. Deaths are not given as a numeric result. These limitations restrict interpretation of both the primary outcome and the safety record; they do not establish that unreported procedures or analyses were not performed.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study of A New Contact Lens Cleaning and Disinfecting Solution — NCT01318577.
- Registry record last updated 2020-10-08; status last verified 2020-10.
- Results first posted 2020-10-08.
- 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
NCT01318577 is a completed, randomized, double-masked, parallel-group study sponsored by Bausch & Lomb Incorporated. It enrolled 444 participants and compared an investigational hydrogen peroxide cleaning and disinfecting solution with Clear Care Solution over approximately three months. The primary outcome was the percentage of eyes with any slit lamp finding above grade 2 at 3 months, based on several listed eye abnormalities graded from 0 to 4.
The registry reports outcome values of 4.0 for the investigational group and 0.0 for Clear Care, while classifying the results as counts of units despite the percentage wording in the outcome title. It lists 442 eyes and 438 eyes with nonmissing scores, respectively, but does not provide a comparative estimate or statistical analysis. Serious adverse event counts are zero in both groups; deaths are not reported numerically. The registry record does not report the endpoint analysis method, missing-data approach, multiplicity strategy, or sample-size justification.