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 Comparison of Lens Fit and Lens Power of a New Contact Lens to Two Marketed Contact Lenses in a Population of Soft Contact Lens Wearers (NCT01244529), a randomized na study. The primary outcome is Lens Centration Acceptance.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01244529 |
| Phase | NA |
| Condition | Myopia |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | Double |
| Enrollment | 41 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Johnson & Johnson Vision Care, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
Soft contact lens wearers with myopia were enrolled. The registry record lists enrollment of 41 participants. The primary-outcome population is described as participants who completed the study, were enrolled and randomized, and were assigned to a study arm; the number meeting all of those conditions is not reported in the registry record.
Intervention
The study evaluated galy A Plus, a new contact lens in the study description. The registry record also names galy A and seno A as study devices. The order of lenses and the base curves assigned to eyes varied across the listed sequences.
Comparator
The stated purpose was to compare the new lens with two marketed lenses. The registry names the lenses galy A Plus, galy A, and seno A; the record does not provide further product details. It describes different base curves for each eye in the sequence descriptions.
Primary question
After 15 minutes of contact lens wear, how many eyes were judged to have acceptable centration for each lens? The investigator classified centration as acceptable when centered or slightly decentered, and unacceptable when substantially decentered. The registry record does not report the category counts or a statistical comparison between lenses.
3. Trial Design
This was a randomized, double-masked, crossover study listed as completed. The registry record lists 41 enrolled participants and identifies myopia as the condition. The study began on 2010-09-01, with primary completion on 2010-11-01. The stated purpose was to evaluate the comparability of lens fit and lens power for a new contact lens and two marketed lenses.
The three named devices are galy A Plus, galy A, and seno A. The sequence descriptions show different orders of these lenses. They also describe different base curves assigned to the eyes for some lenses: 8.3 or 8.7 for galy A Plus and galy A, and 8.4 or 8.8 for seno A. The primary endpoint description says that results aggregate across base curves within each lens type, rather than stratifying the primary outcome by base curve.
In a crossover design, participants receive more than one study condition in an assigned sequence. Comparisons may therefore use observations from the same participants under different conditions, rather than treating every observation as independent. The registry record identifies the crossover model but does not report the timing or duration of each lens period, any washout procedures, or how the analysis handled sequence, period, or participant effects. Those details should not be inferred from the design label alone.
Randomization and double masking are stated in the record, but the method used to generate the random sequence, the allocation process, and who was masked are not reported in the registry record. The record lists the study status as completed; that status does not itself establish that outcome results were posted.
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 | All Arms, All Interventions |
|---|---|
| STARTED | 41 |
| COMPLETED | 41 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Analysis was on those completed subjects who were enrolled, randomized, and assigned to a study arm.
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: All enrolled subjects.
| Characteristic | Unit | All Subjects |
|---|---|---|
| Participants analysed | 41 | |
| Age, Continuous | years | 34.0 (SD 12.4) |
| Sex: Female, Male: Female | Participants | 21 |
| Sex: Female, Male: Male | Participants | 20 |
| Region of Enrollment: United Kingdom | participants | 41 |
6. Primary Endpoint
The registry lists the primary outcome as Lens Centration Acceptance, measured over after 15 minutes of contact lens wear.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | eyes |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is lens centration acceptance, measured as a count of eyes in each category for each lens. An investigator assessed the lens after 15 minutes of contact lens wear. Centered or slightly decentered lenses were classified as acceptable; substantially decentered lenses were classified as unacceptable. The description specifies that counts are aggregated across the different base curves within each lens type because the primary outcome was not stratified by base curve.
Centration is a fit characteristic: it describes the position of the lens on the eye according to the investigator’s assessment. A count by category can describe how often eyes met the study’s stated acceptance criterion. Comparing such counts across lenses could address whether acceptance patterns were similar or different, but interpretation depends on the actual counts and on a suitable statistical analysis. Neither the category counts nor a comparison is reported in the registry record, so the direction, size, and precision of any difference cannot be assessed.
The endpoint is measured in eyes, while the study enrolled participants. In general, observations from two eyes of the same participant may be related rather than independent. Statistical analysis should account for the design and the relationship between observations when appropriate; the registry record does not report how this was handled. The primary endpoint concerns centration acceptance, not the full range of lens-fit characteristics or lens power.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record defines a clinically interpretable endpoint: an investigator’s classification of lens centration as acceptable or unacceptable after 15 minutes of wear. However, it does not report the number of eyes in either category for any lens. It also reports no analyses. Consequently, there is no posted estimate of the frequency of acceptable centration, no comparison between lenses, and no measure of statistical uncertainty for this endpoint.
The trial’s stated aim includes comparability of lens fit and lens power. The primary endpoint addresses one aspect of fit, while the listed secondary outcome concerns new lens power fit match to control lenses. The registry record does not report numerical results for either outcome. It therefore does not establish whether observed outcomes were similar, different, or sufficiently precise to support a conclusion about comparability.
The crossover design and the eye-level measurement matter when interpreting any eventual comparison. A participant may contribute observations under more than one lens condition, and both eyes may contribute observations. These features can create dependence among measurements. A statistical analysis that ignores relevant dependence can misstate uncertainty. The registry record does not report an analysis method or enough results to assess whether such dependence was addressed.
The record lists 41 enrolled participants, but that enrollment number is not the number of analyzed eyes or necessarily the number included in the primary-outcome analysis. The analysis population is described as completed subjects who were enrolled, randomized, and assigned to a study arm. The number of participants or eyes in that population is not reported in the registry record. The distinction matters because incomplete follow-up or unavailable measurements can affect which observations contribute to an estimate.
No confidence intervals, p-values, or other inferential results are reported. A confidence interval, in general, describes the statistical uncertainty around an estimate under the assumptions of the analysis; without an estimate and its uncertainty, precision cannot be judged. No claim about superiority, equivalence, or non-inferiority can be drawn from the design description alone. Such conclusions require prespecified criteria and appropriate analyses, and those details are not reported in the registry record.
The record’s completed status indicates the study is listed as completed, not that its results are available. The posted information supports a description of the planned comparison and endpoint, but not a conclusion about the comparative performance of the lenses.
9. Statistical Methods Explained
The registry record identifies a randomized, double-masked crossover design and an eye-level categorical primary outcome. It does not report the statistical methods used to analyze that outcome. The concepts below explain what would generally matter for interpreting this type of study, not methods confirmed to have been used in this trial.
What does a categorical endpoint represent?
The primary outcome places each assessed eye into one of two categories: acceptable centration or unacceptable centration. The endpoint description defines the categories by the investigator’s assessment after 15 minutes of wear. A count in each category is descriptive: it tells how many recorded eyes fell into that category. To compare lenses statistically, an analysis would also need to define the comparison and account for how observations were collected.
Counts alone do not show how precise a comparison is. In general, an estimated difference can be accompanied by a confidence interval, which indicates a range of values compatible with the data and the statistical assumptions. A p-value, when reported, addresses how inconsistent the data are with a specified null hypothesis under an analysis model. Neither quantity is reported for the primary outcome in the registry record. Without the underlying counts and analysis, neither effect size nor uncertainty can be evaluated.
Why does the crossover structure matter?
In a crossover study, participants receive conditions in a sequence. Measurements from the same person can be correlated because they share participant characteristics. Where both eyes are assessed, observations from the two eyes of one participant may also be correlated. General statistical methods can account for these within-person relationships; treating related observations as independent can make uncertainty estimates unreliable.
Sequence and period can also matter in crossover designs. For example, measurements may vary across the order or timing of conditions for reasons unrelated to the lens being compared. This is a general design consideration, not a claim that such effects occurred in this study. The registry record does not report the period structure, a washout, or the model used to address sequence, period, or participant effects.
What is the role of base curves?
The sequence descriptions assign different base curves to eyes for the named lenses. The primary endpoint description says the counts combine the different base curves into a category by lens type, because the primary outcome was not stratified by base curve. This aggregate approach describes results by lens type rather than estimating separate primary-endpoint results for each base curve. The registry record does not report the counts needed to assess the aggregate results, nor does it report a base-curve-specific analysis.
What can sample-size planning show?
Sample-size calculations are planning tools. The registry record describes a planning illustration based on an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. Such an illustration is not the trial’s own design justification unless the record says so, and the design justification is not reported in the registry record. It also is not observed power. The record does not report a numerical sample-size justification or a statistical analysis plan, and the listed primary outcome has not been reduced to a single comparison in the posted results.
In general, a planning calculation depends on the outcome, target effect, variability or event rate, significance level, allocation, and analysis assumptions. A calculation based on an observed effect is especially dependent on that effect estimate and does not substitute for an analysis of the trial’s results. Any planning illustration should therefore be read as hypothetical rather than as evidence that a particular effect was detected or excluded.
What is not available for this analysis?
The registry record lists four outcome measures and one secondary outcome concerning new lens power fit match to control lenses. It reports zero analyses. The primary outcome counts, analysis estimates, uncertainty measures, and inferential results are not reported in the registry record. The statistical model, handling of correlated eyes, missing observations, sequence effects, and any multiplicity procedure are also not reported. These omissions prevent independent assessment of how the primary comparison was conducted or how precise its results might be.
10. Multiplicity, Missing Data and Analysis Populations
The record lists four outcome measures, identifies lens centration acceptance as the primary outcome, and names new lens power fit match to control lenses as a secondary outcome. It does not report an analysis plan specifying which comparisons were primary, how multiple outcomes or lens comparisons were handled, or whether any adjustment for multiple testing was planned. With multiple endpoints or comparisons, the chance of at least one apparently notable result can increase; statistical approaches to multiplicity can address that issue, but the registry record does not say whether any were used.
The primary outcome description specifies an aggregate by lens type across base curves, but the record does not report how the three lens conditions were compared statistically. It also does not report a multiplicity strategy for comparisons among those lenses. No claim about adjusted or unadjusted significance is possible because no analyses are posted.
The primary-outcome population is described as completed participants who were enrolled, randomized, and assigned to a study arm. The number of participants or eyes meeting that description is not reported in the registry record. The record does not report the number with missing or unusable measurements, reasons for missingness, or how missing observations were handled. It also does not describe whether any additional analysis populations were used. Enrollment of 41 participants should not be treated as the analyzed sample size.
These gaps limit assessment of both bias and precision. In general, missing outcome data can affect estimates if availability is related to the outcome or treatment condition, while multiplicity decisions affect how confirmatory claims should be interpreted. No specific missing-data method, population definition beyond the stated primary-outcome description, or multiplicity procedure should be assumed.
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 |
|---|---|---|---|
| All Arms, All Interventions | 0 | 41 | 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 |
|---|---|
| All Arms, All Interventions | 0 of 41 |
The registry record presents adverse-event figures for all arms and all interventions combined. It lists 41 at risk for serious adverse events and 0 affected; for other adverse events, it also lists 41 at risk and 0 affected. These are aggregate registry figures, not a comparison of adverse events by individual lens.
The record does not list a term among the top serious adverse events. The death count is null, so deaths are not reported in the registry record; null should not be read as a reported count of zero. The record does not provide event descriptions or arm-specific safety counts.
These figures should be read as the adverse-event information posted in the registry, not as proof that no events occurred outside what was recorded or reported. The figures do not establish comparative safety between lenses, and they do not provide an estimate of risk beyond the stated at-risk group. The aggregate format also prevents attributing an event count to a particular study device.
12. What the Result Does, and Does Not, Mean
The registry record describes a randomized, double-masked crossover comparison of galy A Plus, galy A, and seno A in soft contact lens wearers with myopia. It specifies lens centration acceptance as the primary outcome and defines the investigator’s acceptable and unacceptable categories after 15 minutes of wear. It also describes an intention to evaluate lens power fit match.
What the posted record does not show is the number of eyes in each primary-outcome category, the results for the secondary outcome, or statistical comparisons. It contains no reported analyses, estimates, confidence intervals, or p-values. As a result, the comparative magnitude and precision of outcomes cannot be judged. The record does not support a conclusion that the lenses had equivalent, superior, or inferior results.
The design information is not a substitute for results. Randomization, masking, and crossover structure describe features of the study, but conclusions depend on the observed data and appropriate analyses. In general, equivalence or non-inferiority requires a prespecified margin and an analysis designed to address that question. Those criteria and analyses are not reported in the registry record.
The enrollment figure of 41 refers to participants enrolled, not necessarily the number contributing to the primary analysis. The endpoint is recorded for eyes, and the reported population is limited to completed subjects who were enrolled, randomized, and assigned to a study arm. The analyzed number of participants and eyes is not reported. This distinction affects the information available to estimate outcomes and their uncertainty.
The safety entries are aggregate counts across all arms and interventions, while the death count is not reported. They do not provide a lens-by-lens safety comparison. Overall, the registry record establishes the study question, design features, and outcome definitions, but it does not contain the numerical outcome evidence needed to answer whether the lenses differed or how precisely any comparison was estimated.
13. Why This Trial Matters Statistically
This study illustrates a common statistical distinction between a well-defined research question and an answer supported by posted results. The registry record identifies a randomized, double-masked crossover comparison and defines a primary outcome in concrete terms. Yet without the category counts and analysis, readers cannot estimate the observed pattern of centration acceptance or its uncertainty.
The design also highlights why the unit of observation matters. Participants were enrolled, but the primary outcome is measured in eyes. In a crossover study, a participant may contribute measurements under multiple lens conditions, and two eyes from one participant may not provide independent information. Appropriate analysis needs to reflect those relationships. The registry record does not report whether or how the analysis did so.
Aggregation across base curves is another important interpretive choice stated in the endpoint description. The primary outcome was to be reported by lens type, combining base curves rather than stratifying by them. That defines the scope of the planned primary summary, but without the resulting counts it is not possible to assess the aggregate pattern or whether it conceals variation across base curves.
Finally, the record lists several outcome measures but no analyses. This underscores why readers need both outcome definitions and a transparent analysis plan, including how multiple comparisons and incomplete observations are addressed. Design labels and enrollment totals cannot replace effect estimates, precision measures, and clear reporting of the analysis population. For this record, the statistical question is identifiable, but the evidence needed to resolve it is not reported.
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 main limitation for interpreting this trial is that the registry record does not report primary or secondary outcome results. It gives no category counts for lens centration acceptance and no numerical result for new lens power fit match to control lenses. It also reports zero analyses. The comparative effect and its precision therefore cannot be evaluated.
The primary endpoint is described as an eye-level measure, while the study enrolled participants. The number of eyes assessed and the number of participants included in the primary analysis are not reported. The record does not describe how dependence between eyes or repeated measurements within participants was handled. Because the design is crossover, details about periods, sequence effects, and any washout are also not reported.
The endpoint is aggregated across base curves by lens type. No base-curve-specific primary results are reported, and the record does not provide the information needed to determine whether results varied by base curve. The registry record also does not provide a detailed statistical analysis plan, a multiplicity procedure, or a method for handling missing data. The number of participants with missing outcomes and reasons for missingness are not reported.
The registry lists 41 enrolled participants, but that figure does not establish the number analyzed. The primary-outcome population is described as completed subjects who were enrolled, randomized, and assigned to a study arm, without a reported count for that population. Finally, the adverse-event figures are combined across arms and interventions, limiting lens-specific safety interpretation. These reporting limitations prevent a detailed assessment of comparative effectiveness or safety from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Comparison of Lens Fit and Lens Power of a New Contact Lens to Two Marketed Contact Lenses in a Population of Soft Contact Lens Wearers — NCT01244529.
- Registry record last updated 2018-06-19; status last verified 2017-08.
- Results first posted 2012-01-24.
- 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 record describes NCT01244529, a completed randomized, double-masked crossover study sponsored by Johnson & Johnson Vision Care, Inc. It lists 41 enrolled participants with myopia and names three devices: galy A Plus, galy A, and seno A. The stated purpose was to evaluate comparability of lens fit and lens power between a new lens and two marketed lenses.
The primary outcome is the number of eyes classified as having acceptable or unacceptable lens centration after 15 minutes of wear. The record also lists new lens power fit match to control lenses as a secondary outcome. It describes aggregate primary reporting by lens type across base curves.
Numerical outcome results and statistical analyses are not reported in the registry record. Aggregate adverse-event entries list 0 affected for serious and other adverse events among 41 at risk; deaths are not reported. The record does not provide the analyzed number of participants or eyes, analysis methods, missing-data handling, or multiplicity procedures.