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 SYSTANE Ultra Lubricant Eye Drops (NCT00702377), a randomized na study. The primary outcome is Tear Break-up Time.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00702377 |
| Phase | NA |
| Condition | Dry Eye |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 109 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Alcon Research |
| Results posted | Yes |
2. Clinical Question
Population
The registry describes participants as dry eye patients. It records 109 participants enrolled overall, but does not report further details about eligibility, age, sex, baseline tear break-up time, or the number assigned to each group in the primary outcome results. The characteristics of the people represented by the outcome data therefore cannot be assessed from the registry record.
Intervention
The intervention was SYSTANE Ultra Lubricant Eye Drops. The registry lists SYSTANE Ultra as an artificial tear and identifies tear break-up time as the primary outcome measure. Details such as the dosing schedule and the way the drops were used are not reported in the registry record.
Comparator
The comparator was OPTIVE Lubricant Eye Drops, also described in the registry as an artificial tear. The record does not report details about dosing or whether use was otherwise standardized between groups. Both groups are described as part of a randomized, parallel-group trial.
Primary question
The primary question was how tear break-up time, measured in seconds, was evaluated in participants assigned to SYSTANE Ultra or OPTIVE. Measurements were scheduled for Day 0, Day 7, Day 14, Day 28, and Day 42. The registry record gives the outcome definition and measurement schedule, but does not report the group results or a statistical comparison. It is therefore not possible to establish from this record how the measured outcome differed between groups.
3. Trial Design
This was a randomized, quadruple-masked, parallel-group trial of SYSTANE Ultra Lubricant Eye Drops and OPTIVE Lubricant Eye Drops in dry eye patients. The registry lists the study phase as NA and records an enrollment of 109. Randomization indicates that assignment to the treatment groups was intended to be determined by chance; the precise allocation procedure and the number assigned to each group for the primary outcome are not reported in the registry record. A parallel-group design means that participants were assigned to a group and the groups were compared over the study period, rather than participants crossing between treatments.
The registry labels masking as quadruple. That label indicates masking of several participant and study roles, but the record does not identify which roles were masked or explain how masking was implemented. The study is marked completed. Its recorded start was 2008-06 and its primary completion was 2008-09. The registry identifies Alcon Research as the sponsor.
The stated purpose was to evaluate the safety and efficacy of two artificial tears in dry eye patients. The primary outcome was tear break-up time, with measurements scheduled at Day 0, Day 7, Day 14, Day 28, and Day 42. The record also lists three outcome measures overall, but the registry information available for interpretation does not provide a full account of the other measures. Detailed eligibility criteria, treatment instructions, adherence procedures, follow-up procedures, and the protocol’s statistical plan are not reported in the registry record. The design features describe how the trial was organized; they do not by themselves establish the size, direction, or precision of any treatment difference.
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: Randomized, double-masked, parallel design
Overall Study
| Stage | SYSTANE Ultra | OPTIVE Lubricant Eye Drops |
|---|---|---|
| STARTED | 53 | 56 |
| COMPLETED | 52 | 53 |
| NOT COMPLETED | 1 | 3 |
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 | SYSTANE Ultra | OPTIVE Lubricant Eye Drops | Total |
|---|---|---|---|---|
| Participants analysed | 53 | 56 | 109 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 34 | 43 | 77 |
| Age, Categorical: >=65 years | Participants | 19 | 13 | 32 |
| Sex: Female, Male: Female | Participants | 39 | 41 | 80 |
| Sex: Female, Male: Male | Participants | 14 | 15 | 29 |
6. Primary Endpoint
The registry lists the primary outcome as Tear Break-up Time, measured over Day 0, Day 7, Day 14, Day 28, and Day 42.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | seconds |
| Endpoint classification | Continuous Endpoint |
Tear break-up time is the interval between a blink and the development of a dry spot in the tear film, measured in seconds. The registry describes the dry spot as visible after fluorescein staining when viewed under a slit-lamp. It notes that a value less than 10 seconds is abnormal. The planned assessment times were Day 0, Day 7, Day 14, Day 28, and Day 42.
This measure is used to characterize how long the tear film remains without a visible dry spot after a blink. In general, a continuous measurement can retain more detail than a simple classification because it records the measured duration rather than only whether a threshold is crossed. The registry specifies the mean as the summary parameter and standard deviation as the measure of dispersion. The mean describes the average measurement in a group; the standard deviation describes how spread out individual measurements are around that average.
The endpoint definition and schedule do not supply the observed measurements. The registry record does not report group means, standard deviations, changes from baseline, confidence intervals, or a comparison between SYSTANE Ultra and OPTIVE at any scheduled assessment. Consequently, the outcome’s clinical definition can be described, but the recorded information does not establish the direction or magnitude of an observed difference.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies tear break-up time as the primary outcome and specifies repeated assessment at Day 0, Day 7, Day 14, Day 28, and Day 42. It does not post the outcome values for either group. No group means or standard deviations are reported, and no estimated treatment difference, confidence interval, or p-value is available in the registry record. The primary outcome therefore cannot be interpreted as showing a difference in either direction on the basis of the registry information.
The record lists 109 enrolled participants, but this overall enrollment figure does not tell the reader how many participants contributed outcome data at each assessment. Group-specific primary-outcome denominators and the amount of missing outcome data are not reported in the registry record. It is also not possible to determine whether the scheduled assessments were completed by all participants or whether any analysis adjusted for baseline measurements or other factors.
The safety information is distinct from the primary outcome information. The registry lists zero serious adverse events among 53 participants at risk in the SYSTANE Ultra group and zero among 56 at risk in the OPTIVE group. For other adverse events, it lists 3 affected among 53 at risk in the SYSTANE Ultra group and 0 among 56 at risk in the OPTIVE group. These are descriptive counts. The registry does not provide a statistical comparison, event descriptions for the other adverse events, or enough context to establish whether the events were caused by treatment. Deaths are not reported in the registry record.
The absence of posted primary outcome results is not evidence that the groups had the same measured outcome. It also does not show that either group had a particular improvement or worsening. Without estimates and their uncertainty, the size and precision of any difference cannot be evaluated. The registry lists three outcome measures but does not provide a complete set of posted results for the primary measure in the information recorded for this trial.
Randomization and masking are relevant design features because they can reduce some sources of bias when implemented effectively. However, those design labels cannot substitute for the missing outcome data, an account of the analysis, or information about missing measurements. The registry record does not report the allocation method, the detailed masking procedures, the analysis populations, or a statistical analysis plan. Thus the available information supports a description of the intended comparison and the limited adverse-event counts, but not a conclusion about the comparative primary outcome.
9. Statistical Methods Explained
The primary outcome is continuous: tear break-up time is recorded in seconds, and the registry specifies the mean and standard deviation. In general, a mean is a measure of the central value of observations, while a standard deviation describes their spread. These summaries can help readers understand both the typical measurement and how much individual measurements vary. They do not, on their own, describe the uncertainty in a comparison between groups. For that, a treatment-effect estimate and an uncertainty measure, such as a confidence interval, would ordinarily be useful. Neither is reported for the primary outcome in the registry record.
What does repeated measurement mean?
The outcome was scheduled at Day 0, Day 7, Day 14, Day 28, and Day 42. These observations are repeated measurements on participants across follow-up, rather than separate groups of participants at each time. In general, measurements from the same participant may be related to each other. Statistical methods for repeated measurements can account for that relationship, but the particular method used in this trial is not reported in the registry record. It is not possible to tell whether the primary comparison was made at a particular assessment, across all scheduled assessments, or using a model that included the repeated observations.
The outcome description includes the threshold that less than 10 seconds is abnormal, but the registry specifies the mean of a continuous measure as the primary summary. A threshold and a continuous summary answer different questions. In general, using the continuous value retains information about the measured duration, while classifying results by a threshold describes how many measurements fall on one side or the other. The registry record does not report a threshold-based primary analysis or the number of participants with values on either side of the threshold.
How should uncertainty be assessed?
A confidence interval is a statistical range used to express uncertainty around an estimate. In general, a narrower interval indicates greater precision than a wider interval, while the position of the interval describes which values remain compatible with the data and method. A p-value, when reported, summarizes how compatible the data are with a specified null hypothesis under an analysis model. These statistics are not interchangeable with the observed effect itself. The registry record does not report a confidence interval, p-value, or treatment-effect estimate for tear break-up time, so neither the magnitude nor the precision of a primary-outcome comparison can be assessed.
The registry records zero statistical analyses. That means the registry entry does not include a posted analysis of the primary outcome. It does not explain whether analyses were conducted elsewhere, which model would have been used, what assumptions were checked, or whether the analysis followed a prespecified plan. The statistical plan and the justification for the planned enrollment are not reported in the registry record. Consequently, readers cannot evaluate whether the analysis accounted for baseline values, repeated measurements, departures from model assumptions, or other design features.
Why can variability matter?
In general, greater variability in a continuous outcome makes it harder to distinguish a group difference from random variation, all else being equal. A standard deviation is one way to describe that variability. Some continuous outcomes may also have variability greater than a simple model assumes, a property often described as over-dispersion in settings where the model specifies a variance. When over-dispersion is relevant, an analysis that ignores it may understate uncertainty. Whether this issue applied to the trial’s outcome, or whether it was assessed, is not reported in the registry record. There are no posted outcome distributions or model diagnostics with which to evaluate it.
The planning assumptions associated with sample-size illustrations describe hypothetical planning, not the observed trial result. In general, such illustrations depend on assumptions about the effect to detect, significance level, allocation, and statistical model. The record’s stated assumptions use a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect framed as a fraction of the observed effect. The planning illustrations are not evidence of observed power and do not replace the trial’s actual estimates. The registry does not report the trial’s own sample-size justification or the design assumptions used when enrollment was planned. Since the primary outcome results are not reported, a reader also cannot use the posted record to assess an observed primary effect.
Finally, statistical interpretation depends on more than a model label. It requires clarity about who was included, how measurements were handled, what comparison was prespecified, and how uncertainty was estimated. These details are not reported in the registry record. The design information and outcome definition are useful for understanding what was intended to be measured, but they are insufficient to reconstruct or verify an inferential analysis.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome was scheduled for assessment at Day 0, Day 7, Day 14, Day 28, and Day 42. Evaluating an outcome at multiple times can raise a multiplicity question: in general, making several statistical comparisons can increase the chance of finding an apparently notable result by chance if the analysis does not account for the number and structure of the comparisons. A prespecified approach may identify a primary time point, combine repeated observations in a model, or otherwise address multiple comparisons. The registry record does not report which approach, if any, was planned or used. It does not identify a single primary assessment time beyond listing the scheduled time points.
The registry lists three outcome measures in total, but the statistical plan and any multiplicity adjustment are not reported in the registry record. No primary-outcome analysis is posted, so there are no reported comparisons to assess for multiplicity. The record does not report interim analyses or stopping rules; their presence or absence cannot be determined from the available registry information.
Missing data are also important for a repeated-measure outcome. The registry record does not report the number of participants with tear break-up time measurements at each assessment, reasons for missing observations, or methods used to handle missing data. It does not describe whether the analysis included all randomized participants, participants who completed follow-up, or another analysis population. Those analysis-population details are not reported in the registry record. Without them, the relationship between overall enrollment and the observations contributing to any analysis cannot be evaluated.
In general, missingness can affect interpretation when the availability of measurements is related to participant characteristics or outcomes. Different assumptions and methods can lead to different estimates, so reporting the extent of missingness and the analysis approach matters. The registry information does not allow a reader to judge the impact of missing measurements or to compare alternative assumptions.
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 |
|---|---|---|---|
| SYSTANE Ultra | 0 | 53 | 0.0% |
| OPTIVE Lubricant Eye Drops | 0 | 56 | 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 |
|---|---|
| SYSTANE Ultra | 3 of 53 |
| OPTIVE Lubricant Eye Drops | 0 of 56 |
Most frequent non-serious adverse event terms
| Event term | Organ system | SYSTANE Ultra | OPTIVE Lubricant Eye Drops |
|---|---|---|---|
| Urinary Tract Infection | Infections and infestations | 3 of 53 | 0 of 56 |
The registry lists serious adverse events separately from other adverse events. For SYSTANE Ultra, it records 0 serious events among 53 participants at risk and 3 participants affected by other adverse events among 53 at risk. For OPTIVE Lubricant Eye Drops, it records 0 serious events among 56 participants at risk and 0 participants affected by other adverse events among 56 at risk. These are the counts in the registry record; they are not a statistical comparison between groups.
A count of zero observed serious events does not establish that the possibility of such events is zero. In general, event counts from a trial describe what was recorded among participants followed, and their interpretation depends on the size of the groups, follow-up, event definitions, and completeness of reporting. The registry does not provide event descriptions for the three other adverse events, their timing, severity, or an assessment of whether they were related to treatment. It also does not report a statistical analysis of these counts. Deaths are not reported in the registry record.
The at-risk counts for these safety entries are not a substitute for the number of participants with primary outcome measurements. They should be read as the denominators attached to the registry’s adverse-event counts. These data alone do not establish a causal relationship or support a broader safety conclusion.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, quadruple-masked, parallel-group comparison of SYSTANE Ultra Lubricant Eye Drops and OPTIVE Lubricant Eye Drops was conducted in dry eye patients. It specifies tear break-up time, measured in seconds, as the primary outcome and gives the scheduled assessment times. It also reports limited adverse-event counts. These details describe the trial’s intended comparison and some recorded safety information.
The record does not report the primary outcome values or an inferential comparison. It therefore cannot establish whether the mean tear break-up time differed between groups, which group had the larger mean, or how precise any difference might have been. The lack of posted results should not be interpreted as no difference, as evidence of equivalence, or as evidence that either treatment improved the outcome. Those interpretations require outcome estimates and an appropriate analysis.
In general, an estimated treatment difference addresses the size and direction of a comparison, while its uncertainty indicates how precisely that difference is estimated. A conclusion about whether a result is compatible with a range of effects requires those estimates and the analysis context. Neither the primary effect estimate nor its uncertainty is reported in the registry record. The listed sample-size assumptions are planning illustrations, not observed power and not a replacement for the trial’s outcome results.
The adverse-event counts also have a limited scope. The registry records no serious adverse events in either group and records other adverse events in the SYSTANE Ultra group but none in the OPTIVE group. Without event descriptions, follow-up context, and an analysis, those counts do not establish that treatment caused or prevented events. The deaths field is not reported in the registry record.
Accordingly, the registry supports a description of the study design, endpoint definition, assessment schedule, and reported event counts, but not a conclusion about comparative efficacy or a comprehensive safety profile. The distinction is important: a completed trial record can describe planned methods and selected outcomes without providing enough results to answer the trial’s primary comparative question.
13. Why This Trial Matters Statistically
This trial is statistically informative as an example of the difference between a clearly identified endpoint and an interpretable treatment-effect result. The registry names tear break-up time, defines how it is measured, specifies the summary as a mean with standard deviation, and lists repeated assessment times. That information helps readers understand what investigators intended to measure. It does not by itself show what was observed or how the treatments compared.
Repeated measurements make analysis choices important. In general, an analysis must account for the fact that measurements taken from the same participant can be related. It also needs to make clear how the scheduled time points contribute to the primary question and how missing observations are handled. The registry record does not report the model, the analysis population, or the missing-data approach. Readers therefore cannot evaluate those choices or reproduce a primary analysis from the posted information.
The record also illustrates why event counts and outcome estimates answer different questions. The adverse-event counts describe events recorded in the groups, whereas the primary outcome would require group measurements and a comparison to describe the treatment effect. The limited event counts cannot fill the gap left by the missing tear break-up time results. Neither the design labels nor the completed status provide the missing estimates.
For clinical research readers, a registry entry is most useful when it connects the planned outcome to posted results, analysis details, and uncertainty estimates. In this case, the study’s primary question is identifiable, but the registry record does not report the results needed to assess its answer. That makes it a useful reminder to distinguish what a trial was designed to evaluate from what its publicly recorded results allow readers to conclude.
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 central limitation for interpretation is that the registry record does not report primary outcome results. There are no posted group means or standard deviations for tear break-up time, no treatment-effect estimate, and no confidence interval or p-value. The registry lists three outcome measures overall, but the primary comparative result cannot be assessed from the recorded information.
The outcome schedule includes Day 0, Day 7, Day 14, Day 28, and Day 42, but the record does not report measurements at these times, the number of participants assessed at each time, or how observations were combined in an analysis. The protocol’s statistical plan, the primary analysis time point, the method for repeated measurements, and any handling of baseline values are not reported in the registry record. The registry also does not describe missing-data procedures or the analysis populations.
The record gives an overall enrollment of 109 but does not report the number randomized to each group for primary outcome analysis or the number completing follow-up. It does not provide detailed participant characteristics, eligibility criteria, treatment instructions, adherence information, or allocation procedures. These omissions limit assessment of how the enrolled participants relate to the population of interest and how the design was implemented.
Safety reporting is limited to counts. Descriptions and timing for the other adverse events are not reported, and the record does not provide a causal assessment or a statistical comparison. Deaths are not reported in the registry record. The registry’s quadruple-masking label is not accompanied by a description of which roles were masked or how masking was maintained. These limitations do not establish that the study lacked such procedures; they indicate that the registry entry does not report them.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Evaluation of SYSTANE Ultra Lubricant Eye Drops — NCT00702377.
- Registry record last updated 2012-02-02; status last verified 2012-01.
- Results first posted 2010-02-10.
- 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
The registry describes a completed, randomized, quadruple-masked, parallel-group trial sponsored by Alcon Research. It enrolled 109 dry eye patients and compared SYSTANE Ultra Lubricant Eye Drops with OPTIVE Lubricant Eye Drops. The recorded start was 2008-06 and primary completion was 2008-09.
Tear break-up time, measured in seconds, was the primary outcome, scheduled for Day 0, Day 7, Day 14, Day 28, and Day 42. The registry record does not report primary outcome results or a statistical comparison. It records zero serious adverse events in each group and other adverse events affecting 3 participants in the SYSTANE Ultra group and 0 in the OPTIVE group. The event details and deaths are not reported in the registry record.