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 Long-term Results After Intravitreal Bevacizumab Treatment Of Neovascular Age-related Macular Degeneration (NCT01027468), a na na study. The primary outcome is Vision.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01027468 |
| Phase | NA |
| Condition | Neovascular Age-related Macular Degeneration |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 160 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Medical University of Vienna |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns eyes with neovascular age-related macular degeneration. The brief summary describes treatment-naive eyes as group 1 and eyes with prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide as group 2. Eligibility details beyond this description are not reported in the registry record.
Intervention
The listed intervention is bevacizumab by intravitreal injection. The group 1 arm description specifies a bevacizumab intravitreal injection. The registry record does not report a detailed injection schedule or other protocol details.
Comparator
This is recorded as a single-group study with no randomized allocation. The brief summary describes a comparison between treatment-naive eyes and eyes with prior treatment. That is a comparison of groups with different treatment histories, not a like-for-like randomized control comparison.
Primary question
The primary outcome is best-corrected visual acuity converted to logMAR, assessed 3 years after the first intravitreal bevacizumab treatment. The study description also mentions central retinal thickness and systemic complications, but the registry record does not report numerical results for these outcomes.
The clinical question is therefore descriptive: what visual acuity was recorded at the specified follow-up, and how did the described groups compare? The record does not give the group-level visual acuity means or standard deviations, or an estimated contrast between groups. It consequently does not establish how visual acuity changed from before treatment, because a baseline value and a change analysis are not reported. Nor does it establish that any difference between the groups was caused by bevacizumab. The groups are distinguished by prior treatment history, and the record does not describe a randomized allocation that would make them exchangeable at study entry.
3. Trial Design
The registry identifies this study as a single-group intervention study with bevacizumab listed as a drug. Allocation is recorded as NA and masking as NONE. The record lists enrollment as 160 and names the Medical University of Vienna as sponsor. The condition is neovascular age-related macular degeneration, and the study status is completed.
The brief summary describes treatment-naive eyes as group 1 and eyes previously treated with photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide as group 2. It says that data from those groups were compared. This group comparison does not turn the design into a randomized controlled trial: the registry records a single-group model, and allocation is NA. The groups also differ in their stated treatment history, so their contrast should be read as observational rather than as a randomized estimate of treatment effect.
The enrollment field gives 160, while the brief summary says that 200 eyes with each subtype of neovascular age-related macular degeneration will be included. These statements do not align, and the registry record does not explain the difference or clarify whether the counts refer to people, eyes, planned enrollment, or analyzed observations. The number actually analyzed for the primary outcome is not reported in the registry record.
The recorded study start is 2009-08 and primary completion is 2009-11. The primary outcome timeframe is 3 years after the first intravitreal bevacizumab treatment. The registry record does not explain how the recorded primary-completion date relates to that follow-up timeframe. It also does not report recruitment details, follow-up completeness, or the timing and number of outcome assessments beyond the stated primary timeframe.
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: Inclusion criteria: * patients treated with bevacizumab due to wet age-related macular degeneration * follow-up of 3 years Exclusion criteria: \- patients with other macular diseases
Overall Study
| Stage | Group 1 |
|---|---|
| STARTED | 160 |
| COMPLETED | 160 |
| NOT COMPLETED | 0 |
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 | Group 1 |
|---|---|---|
| Participants analysed | 160 | |
| Age, Customized | years | 77.24 (SD 10.56) |
| Sex: Female, Male: Female | Participants | 102 |
| Sex: Female, Male: Male | Participants | 58 |
6. Primary Endpoint
The registry lists the primary outcome as Vision, measured over 3 years after first intravitreal bevacizumab treatment.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | logMAR |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is best-corrected visual acuity, converted to logMAR for statistical analysis. The registry gives the outcome title as Vision, the unit as logMAR, and the summary measure as a mean with standard deviation. The stated timeframe is 3 years after the first intravitreal bevacizumab treatment.
Visual acuity is a functional measure: it records how well a participant can see under the specified assessment conditions. In general, converting visual acuity to logMAR places measurements on a scale suitable for statistical analysis. It expresses visual acuity through the minimum angle of resolution, as the registry description notes. The registry says that acuity was to be measured using Snellen charts at 6m.
In general, a mean describes the central value of a set of measurements, while a standard deviation describes their spread around that mean. Reporting both can convey the average visual acuity and the variability among the measurements, but they do not by themselves show the range of individual outcomes or the precision of an estimated group difference.
The endpoint definition does not supply an observed mean, standard deviation, baseline measurement, or group contrast. Those results are not reported in the registry record. Central retinal thickness is also mentioned in the brief summary, with Stratus OCT and Cirrus SD-OCT named as measurement methods, but the primary endpoint specified in the registry is visual acuity rather than retinal thickness.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a clinically interpretable primary measure and a follow-up timeframe, but it does not report the numerical primary outcome. The mean logMAR visual acuity and its standard deviation at 3 years are not reported in the registry record. No estimated difference between group 1 and group 2, confidence interval, or test result is reported either. The record therefore cannot establish the direction or size of a group contrast, or how precisely such a contrast was estimated.
The design matters when reading the stated comparison. Group 1 is described as treatment-naive, whereas group 2 had prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide. An observed difference between these groups could reflect differences in treatment history or other differences between the groups, as well as any association with subsequent bevacizumab treatment. The registry does not report enough information to separate these possibilities. The comparison should not be interpreted as a randomized estimate of bevacizumab's effect.
In general, a confidence interval communicates the range of effect estimates compatible with the data and the analysis assumptions. A narrow interval indicates greater statistical precision than a wide interval, but precision does not by itself remove bias from a non-randomized comparison. No confidence interval is reported in the registry record, so the precision of the primary result cannot be evaluated.
The study description proposes measurement 3 years after the first injection, but the available record does not give the number of observations at that time or the completeness of follow-up. Without those details, it is not possible to assess whether the reported group means, if available elsewhere, would represent all enrolled participants or only those with measured outcomes. The recorded enrollment and the number of eyes described in the brief summary also differ, and the record does not reconcile them.
The registry lists 3 outcome measures and 0 analyses. This indicates that analysis results are not represented in the posted registry record; it does not permit reconstruction of the underlying findings. The intervention, outcome definitions, and safety counts alone are insufficient to conclude whether visual acuity improved, worsened, or remained stable, either overall or within a group. No clinical conclusion about efficacy should be drawn from the endpoint description in the absence of its results.
9. Statistical Methods Explained
The registry describes a continuous primary outcome summarized by a mean and standard deviation. Those choices describe the distribution of visual acuity measurements, but an outcome summary is not itself a treatment-effect analysis. The record reports no mean, standard deviation, between-group estimate, confidence interval, or test result for the primary endpoint.
What does the logMAR mean represent?
The endpoint is best-corrected visual acuity converted to logMAR, with MAR defined in the registry as minimum angle of resolution. In general, a transformation changes the scale on which data are represented so that statistical summaries and comparisons can be made in a useful way. The endpoint description identifies the transformed measure, but does not provide individual observations or group summaries. No direction or magnitude of a visual acuity difference can therefore be inferred from the scale name alone.
In general, a mean is useful for describing the center of a continuous distribution. A standard deviation describes how dispersed measurements are around the mean. It is not the same as a confidence interval: the standard deviation describes variation among observations, while a confidence interval describes uncertainty in an estimated quantity. The registry specifies standard deviation as the dispersion measure but does not report its value or a confidence interval for the primary outcome.
What would a group comparison mean?
The study summary describes a comparison of treatment-naive eyes with eyes that had received prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide. In general, a difference between group means describes an association between group membership and the measured outcome. It does not automatically identify a causal treatment effect. Here, the groups have different stated treatment histories and the record gives no randomized allocation. The registry itself notes that the arms are not a like-for-like control comparison. An adjustment strategy or other method for addressing group differences is not reported in the registry record.
The primary outcome is specified at 3 years after the first intravitreal bevacizumab treatment. The record does not state whether the analysis compared values at that time only, compared changes from baseline, or used another model. Those approaches answer different questions and can rely on different assumptions. Baseline visual acuity, repeated measurements, and a prespecified analysis model are not reported in the registry record.
What do the planning assumptions describe?
The registry describes a sample-size planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The illustration is described as targeting a stated fraction of the observed effect. These are planning assumptions, not evidence that the trial was designed or conducted using those settings. The registry does not report the trial's own sample-size justification, and the observed primary effect needed to interpret such an illustration is not reported in the registry record.
In general, a sample-size calculation estimates how many observations a future study would need under specified assumptions about the effect, variability, significance level, and desired power. Such an estimate is a planning illustration, not an observed result and not a measure of the probability that a completed study's conclusion is correct. The equal-allocation assumption in the illustration is distinct from the registered single-group model and the described comparison of eyes with different treatment histories. The assumptions should not be mistaken for the study's actual design.
For count outcomes, over-dispersion can matter when observed variability exceeds what a statistical model assumes. In general, ignoring over-dispersion can make uncertainty appear too small and tests too optimistic. This is a general consideration rather than a reported feature of this study: the primary endpoint is continuous, and the registry record does not report an over-dispersion assessment or a count-outcome model.
What can be inferred from the analysis record?
The registry lists 0 analyses. It does not report an analysis population, model specification, covariate adjustment, handling of repeated observations, missing-data method, or inferential result for visual acuity. It also does not report interim analyses or a full statistical analysis plan. These items cannot be reconstructed from the endpoint definition or from the safety counts. General statistical interpretation can explain what these methods would do, but cannot substitute for study-specific results.
Because the registry does not give an outcome estimate or its uncertainty, there is no basis in this record for describing statistical significance, precision, or the magnitude of an association. If an analysis elsewhere recalculates a contrast from summary statistics, that would be an unadjusted recalculation rather than a substitute for a sponsor analysis. The registry record contains no sponsor analysis result against which to compare such a recalculation.
10. Confidence Intervals for Each Arm
No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.
| Arm | Participants | Mean | Standard deviation | 95% CI for the mean |
|---|---|---|---|---|
| Group 1 | 160 | 0.160 | 0.210 | 0.127 to 0.193 |
R code and output
arm <- c("Group 1")
n <- c(160)
m <- c(0.16)
sp <- c(0.21)
sd <- sp # posted standard deviations
for (i in seq_along(n)) {
se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}
CARM Group 1 160 0.160 0.210 0.127 0.19311. Multiplicity, Missing Data and Analysis Populations
The registry lists 3 outcome measures, with Vision identified as the primary outcome and Systemic Complications After Treatment listed as a secondary outcome. The other outcome measures and their analysis details are not reported in the registry record. The number of analyses is listed as 0.
When a study evaluates multiple outcomes or performs multiple statistical tests, the chance of at least one apparently unusual result can increase. In general, a multiplicity strategy specifies which outcomes or comparisons are confirmatory and how inference will account for the set of tests. The registry record does not report a multiplicity plan, a hierarchy of secondary outcomes, or an adjustment method. It is therefore not possible to determine how any set of outcome comparisons was intended to be interpreted.
Missing-data handling is also not reported in the registry record. The record does not state how many participants or eyes had primary outcome measurements at follow-up, how incomplete follow-up was handled, or whether any imputation or sensitivity analysis was used. In general, missing outcome data can affect both the representativeness of a summary and the validity of a comparison, particularly when missingness differs between groups or relates to the outcome. No study-specific assessment of these issues is available in the registry record.
The analysis population is not reported in the registry record. It is not stated whether the endpoint summaries include all enrolled participants, all treated participants, or only those with outcome measurements. The record also does not report a statistical analysis plan or interim analyses. These omissions prevent assessment of whether the reported analyses, if any, followed prespecified methods.
12. 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 |
|---|---|---|---|
| Group 1 | 5 | 160 | 3.1% |
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 |
|---|---|
| Group 1 | 0 of 160 |
Most frequent serious adverse event terms
| Event term | Organ system | Group 1 |
|---|---|---|
| intraocular inflammation | Eye disorders | 5 of 160 |
Serious events with the highest arm-level rate: intraocular inflammation (3.1%).
The registry lists serious adverse events for group 1 with 160 at risk and 5 affected. It lists other adverse events with 160 at risk and 0 affected. In the serious adverse event terms, intraocular inflammation is listed at 3.1%. These are the safety figures recorded for this group; the registry does not provide enough detail to establish the timing, duration, severity distribution, or relationship of each event to treatment.
The 160 at-risk figures are registry counts, not evidence that all participants completed follow-up or contributed to the visual acuity endpoint. The record does not clarify the relationship between participants and eyes for these counts, or how adverse events were collected over the study period. The death count is not reported in the registry record.
In general, an adverse-event count describes what was recorded in a study population, while attributing an event to a treatment requires a separate assessment. A count alone does not establish causation, and a zero count for other adverse events does not prove that no such events could occur. The registry record does not report a control group suitable for a like-for-like safety comparison, nor does it give enough information to estimate comparative risk. The listed figures should be read as registry-reported observations rather than as a comprehensive measure of safety.
13. What the Result Does, and Does Not, Mean
The record documents a study of intravitreal bevacizumab in neovascular age-related macular degeneration and specifies visual acuity as the primary outcome at 3 years after the first treatment. It also describes a comparison between treatment-naive eyes and eyes with prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide. That information defines the intended clinical question and the broad design, but it does not provide the primary outcome findings.
The registry record does not report the mean logMAR visual acuity, its standard deviation, or a group contrast. It therefore does not show the magnitude or direction of a difference, the precision of an estimate, or whether any comparison met a statistical threshold. The safety record lists serious and other adverse-event counts, but those counts do not establish that bevacizumab caused or prevented the events.
In general, an observational comparison can identify an association but may not isolate the effect of an intervention. The prior-treatment group and the treatment-naive group differ by definition in treatment history. Without random allocation or a reported analysis that addresses relevant group differences, an observed contrast would not by itself establish what would have happened to the same eyes under a different treatment history.
The registry also does not report a baseline visual acuity result, a change-from-baseline analysis, the number of outcomes observed at follow-up, or the handling of missing observations. As a result, the record cannot establish whether visual acuity changed over time or how representative a follow-up summary would be. The enrollment field and the brief summary's stated eye counts are not reconciled, adding uncertainty about the planned and analyzed populations.
The appropriate reading is limited: the registry defines outcomes and records a study design, but does not provide the efficacy results needed to characterize visual acuity outcomes. It also does not support a conclusion that the intervention works or does not work. The absence of a result in the registry record is not evidence that the outcome was unchanged; it means that the outcome estimate is not reported there.
14. Why This Trial Matters Statistically
This study illustrates why a clear outcome definition is only part of the evidence needed to interpret a clinical trial. The registry names a functional endpoint, specifies its logMAR scale and summary measure, and gives a follow-up timeframe. Without the mean, standard deviation, group contrast, and uncertainty estimate, however, readers cannot assess the size, direction, or precision of the primary finding.
The design description also highlights the difference between a randomized comparison and a comparison based on prior treatment history. A single-group model with no randomized allocation can describe outcomes after treatment and can compare groups as observed, but it does not ensure that those groups are comparable at the start. This is important when a comparison is used to make causal claims: treatment history and other differences may influence the outcome independently of the intervention being evaluated.
The record further demonstrates why denominators and analysis populations matter. The enrollment field records 160, while the brief summary describes 200 eyes with each subtype. The registry does not explain how those statements relate or identify the number contributing to the primary endpoint. Clear accounting of participants, eyes, follow-up, and missing outcomes is necessary for judging how a result applies to the study population.
Finally, the registry distinguishes an endpoint description from a reported analysis: it lists 3 outcome measures and 0 analyses. A protocol-like description can establish what investigators planned to measure, but it cannot replace estimates and uncertainty. For biostatistical interpretation, the result, its precision, the population analyzed, and the method used all matter alongside the clinical question.
15. 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 primary limitation of the registry record is the absence of numerical results for the primary endpoint. It does not report the mean logMAR visual acuity, standard deviation, group-specific summaries, or an estimated comparison. It also does not report a confidence interval or test result. The magnitude and precision of any visual acuity finding therefore cannot be assessed from this record.
The comparison is not randomized. The brief summary contrasts treatment-naive eyes with eyes that had prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide, and the registry identifies a single-group model with allocation recorded as NA. This is not a like-for-like control comparison. The record does not describe adjustment for differences between groups, so a causal interpretation is not supported by the design information available.
The population counts are unclear. Enrollment is recorded as 160, while the brief summary says that 200 eyes with each subtype will be included. The registry does not reconcile those figures, clarify the unit of enrollment, or report how many participants or eyes contributed to each outcome. The analysis population and follow-up completeness are not reported in the registry record.
The recorded study dates also leave the timing unclear: the study start is 2009-08, primary completion is 2009-11, and the primary endpoint timeframe is 3 years after the first injection. The registry does not explain how these dates relate. Protocol details, baseline outcome values, missing-data handling, multiplicity procedures, and the statistical analysis plan are not reported in the registry record. These limitations constrain interpretation independently of the absence of outcome estimates.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Long-term Results After Intravitreal Bevacizumab Treatment Of Neovascular Age-related Macular Degeneration — NCT01027468.
- Registry record last updated 2019-04-24; status last verified 2019-04.
- Results first posted 2014-02-20.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
19. Record Summary
The registry describes a completed, single-group study of intravitreal bevacizumab for neovascular age-related macular degeneration, sponsored by the Medical University of Vienna. Enrollment is recorded as 160. The primary outcome is mean best-corrected visual acuity converted to logMAR, with standard deviation, at 3 years after the first injection.
The brief summary describes treatment-naive eyes and eyes with prior photodynamic therapy with verteporfin and intravitreal triamcinolone acetonide, while the registered design does not include randomized allocation. The summary says 200 eyes with each subtype will be included, a count the record does not reconcile with the enrollment field.
The registry lists 3 outcome measures and 0 analyses. Numerical results for the primary outcome, uncertainty estimates, and analysis details are not reported in the registry record. Serious adverse events are listed as 5 affected among 160 at risk; other adverse events are listed as 0 affected among 160 at risk. Intraocular inflammation is listed among serious terms at 3.1%.