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 Increasing Use of the Vaccine Against Herpes Zoster/Shingles at NYULMC and Bellevue Hospital (NCT01483378), a non-randomized na study. The primary outcome is Answers to Survey Questions.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01483378 |
| Phase | NA |
| Condition | Herpes Zoster |
| Allocation | Non-Randomized |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 170 |
| Arms in the primary outcome | n/a |
| Lead sponsor | NYU Langone Health |
| Results posted | Yes |
2. Clinical Question
Population
Patients enrolled in a study of herpes zoster vaccination at NYULMC and Bellevue Hospital. The study description focuses on eligible patients screened in a General Eye Clinic at a major urban public hospital. The registry does not report further participant characteristics or the number eligible for vaccination.
Intervention
The study aimed to increase vaccination by having ophthalmologists screen patients for eligibility and a nurse administer the vaccine in the General Eye Clinic. The registry lists “Choosing to receive the vaccine” as the intervention; it does not describe a randomized assignment to a vaccination strategy.
Comparator
Patients who chose to receive the vaccine were compared with patients who declined it. These groups arose from patients’ choices rather than random allocation, so they are not like-for-like control groups. Differences in survey answers may reflect differences between the groups that were present before vaccination.
Primary question
The study’s stated purpose was to determine whether screening and on-site nurse administration would increase vaccination among eligible patients. The registered primary outcome, however, is survey answers compared between patients who accepted and declined vaccination. The registry record does not report the survey results or a numerical estimate of any change in vaccination rate.
The central statistical distinction is between the service goal and the outcome recorded for analysis. A change in vaccination rate would address whether the clinic approach was followed by greater uptake. The registered outcome instead describes survey responses among patients grouped according to their vaccination choice. Such a comparison can describe how respondents differed, but without random assignment it cannot isolate the effect of screening or vaccine availability from patients’ own preferences and other differences.
The study therefore raises a practical question about implementing vaccination in an eye clinic and a separate descriptive question about the characteristics, eligibility, and attitudes of those who accepted or declined. The registry gives the intended setting and comparison but does not report numerical answers to either question.
3. Trial Design
The registry identifies this as a completed, nonrandomized study with no masking and a single-group model. It lists an enrollment of 170. The study title names NYULMC and Bellevue Hospital, and the sponsor is NYU Langone Health. The phase is listed as NA. The recorded start is 2012-01, with primary completion in 2012-02.
The study description says ophthalmologists screened patients for eligibility and a nurse administered vaccine in the General Eye Clinic. The intervention is recorded as “Choosing to receive the vaccine.” One group is described as eligible patients who chose vaccination; the other consists of patients who declined. This means group membership was determined by patient choice, not random assignment. Although the registry calls the overall model single-group, the primary outcome description compares survey results across these two choice-based groups.
That design can document what happened in the clinic and describe differences between people who accepted and declined. It does not create a randomized control group. A contrast between the groups may be affected by baseline characteristics, eligibility, attitudes, or other factors related to the decision to vaccinate. The registry does not report an adjustment strategy to address such differences.
The timeframe attached to the primary outcome is January 9, 2012 to February 12, 2012. The outcome description says all enrolled patients completed a survey covering baseline characteristics, vaccine eligibility, and attitudes toward vaccination. It does not state how participants were identified beyond the screening context, or report additional details about recruitment, consent, clinic workflow, or follow-up.
The registry lists one outcome measure and zero analyses. It does not report a protocol, a detailed statistical analysis plan, a sample-size justification, or interim analyses. The planning assumptions associated with planning illustrations describe an illustrative calculation rather than the original design; they should not be taken as evidence that the study was planned as a randomized, equally allocated two-arm trial.
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 | Patients Who Received the Herpes Zoster Vaccine | Patients Who Declined the Herpes Zoster Vaccine |
|---|---|---|
| STARTED | 100 | 66 |
| COMPLETED | 100 | 66 |
| NOT COMPLETED | 0 | 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.
Population: 170 patients were enrolled in the study, however 2 met FDA contraindications for herpes zoster vaccination and 2 already received the vaccine, so only 166 were included in the analysis.
| Characteristic | Unit | Survey Participants |
|---|---|---|
| Participants analysed | 166 | |
| Age Continuous: Age | years | 68 (SD 15) |
| Sex: Female, Male: Female | Participants | 94 |
| Sex: Female, Male: Male | Participants | 72 |
| Region of Enrollment: United States | participants | 166 |
6. Primary Endpoint
The registry lists the primary outcome as Answers to Survey Questions, measured over January 9, 2012 to February 12, 2012.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | Percentage of responders |
| Endpoint classification | Binary Endpoint |
The registered primary outcome is “Answers to Survey Questions,” expressed as the percentage of responders, with a 95% confidence interval listed as the measure of dispersion. The survey is described as covering baseline characteristics, eligibility for the herpes zoster vaccine, and attitudes toward vaccination. Its results were intended to be compared between patients who accepted vaccination and those who declined.
Survey measures can help characterize the people who made each choice and describe their reported views. In a clinic implementation study, information about eligibility and attitudes may help explain how patients engaged with the vaccination offer. But the endpoint as registered is not itself a direct estimate of the effect of the clinic approach on vaccination uptake. Nor does the outcome title identify specific survey questions, response categories, or a single prespecified survey item.
The registry does not report numerical response percentages, confidence limits, or the actual survey findings. It also does not clarify whether each survey question was treated as a separate outcome, how a “responder” was defined for every item, or how incomplete responses were handled. Although the outcome description says all enrolled patients completed a survey, item-level completeness and the analysis population are not reported in the registry record.
A percentage communicates the share of respondents with a particular answer, while a confidence interval conveys uncertainty around an estimate. These are general statistical interpretations; without posted values, neither the direction nor the precision of any survey finding can be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a clinic-based effort to promote herpes zoster vaccination and a comparison of survey responses among patients who accepted or declined vaccination. It does not post numerical survey results. Consequently, the record does not establish which group reported more favorable attitudes, how many respondents were eligible, or what proportion chose vaccination. No effect estimate or confidence interval for the primary outcome is reported.
The registered purpose was to determine whether vaccination rate would increase when ophthalmologists screened patients for eligibility and a nurse administered the vaccine in the General Eye Clinic. That is an implementation question about the clinic process. The registered primary outcome is instead a comparison of survey answers by vaccination choice. Without a reported vaccination-rate estimate or a before-and-after comparison, the record does not quantify whether uptake increased.
The design further limits interpretation of any comparison between acceptors and decliners. Patients selected their own group by choosing whether to receive the vaccine. Such groups can differ in attitudes, baseline characteristics, eligibility, or other factors. Therefore, even if group-specific survey percentages were available, the contrast would be descriptive and would not by itself show that the vaccination process caused differences in responses or choices.
The outcome description states that all enrolled patients completed a survey. That statement does not provide response counts for individual questions, confirm that every item was complete, or identify the population used for each calculation. The registry lists zero analyses, and no results for the primary endpoint are presented. Thus, neither statistical significance nor the size and precision of any group difference can be evaluated from the record.
The adverse-event fields list zero serious events among 100 at risk in the vaccinated group, and 11 other events among 100 at risk. For patients who declined, the fields list zero at risk and zero affected for both categories. These entries describe the registry’s reported counts; they should not be interpreted as a complete comparative safety assessment. Deaths are not reported in the registry record, and the meaning or ascertainment of the other-event category is not detailed.
Planning calculations based on fractions of an observed effect are planning illustrations, not observed power. The registry record does not provide the observed effect or the endpoint results needed to judge those calculations as a reflection of the study’s findings. The planning assumptions also specify equal allocation, whereas the actual comparison is based on patient choice and is not randomized.
Overall, the record supports a description of the intended clinical workflow, survey topics, and nonrandomized comparison. It does not support a numerical conclusion about the magnitude of vaccination uptake, the relationship between survey responses and vaccine choice, or the precision of those relationships. Any such conclusion would require results not reported in the registry record.
9. Statistical Methods Explained
The primary outcome is expressed as a percentage of responders, and the registry lists a 95% confidence interval. These are standard ways to report a binary response: each person’s answer is classified into a response category, and the percentage describes the share in a category. The registry does not specify the response categories or provide the percentages, so the endpoint’s numerical results cannot be reconstructed from the record.
What does a confidence interval convey?
In general, a confidence interval describes the statistical uncertainty around an estimate under the assumptions of the method used. A narrower interval indicates greater precision, while a wider interval indicates less precision. It is not a guarantee that the interval contains the true value, nor does it correct for bias in how participants were selected or grouped. Here, the record names a 95% confidence interval but does not post its limits or state the calculation method.
For a comparison of survey responses, an analysis might report a percentage within each group and a contrast between groups. These are distinct quantities: group percentages describe each group, while a contrast describes their separation. The registry does not provide the specific survey items, estimates, contrasts, or inferential tests. It also lists zero analyses, so no particular model or test can be attributed to the study based on the registry record.
Why does nonrandom allocation matter?
Random allocation is a design method intended to balance measured and unmeasured characteristics between comparison groups, on average. This study did not use random allocation. Patients who accepted vaccination and patients who declined may have differed before the clinic offer, including in attitudes or other baseline characteristics. A descriptive difference between their survey answers may therefore reflect selection into groups rather than an effect of the vaccination workflow.
Statistical adjustment can sometimes account for measured differences, but it cannot automatically remove unmeasured confounding, and it depends on details of the analysis. The registry record does not report an adjustment plan or an adjusted analysis. It would therefore be inappropriate to present the choice-based comparison as a randomized treatment effect.
How should the planning assumptions be read?
The planning assumptions describe an illustration using a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect set as a stated fraction of the observed effect. These are assumptions for planning calculations, not evidence about how the original study was designed or analyzed. In particular, equal allocation is an illustrative assumption and does not change the fact that the study groups were formed by patient choice.
For general context, a sample-size calculation estimates how many participants per arm might be needed under specified assumptions to achieve a target probability of detecting an effect. Such calculations depend on the effect size, variability, significance level, allocation, and statistical method. They are not observed power, and a planning illustration does not show whether an analysis actually detected an effect. The record does not report the outcome estimates needed to judge the observed effect or its precision.
The assumptions also mention a normal approximation. In general, an approximation is a simplified way to obtain an estimate or planning calculation; its suitability depends on the data and design. The record does not provide enough outcome detail to assess that suitability for the survey responses. If responses were sparse or unevenly distributed, the properties of an approximation could differ from those expected under its assumptions. No claim about such data patterns can be made because the response counts are not reported.
What can be concluded from the analysis record?
The registry identifies a percentage-based primary outcome and a confidence-interval format, but it does not give an analysis population, a definition of each responder denominator, a test, a model, or numerical results. It also does not report whether comparisons were adjusted, whether assumptions were checked, or how multiple survey items were handled. These details matter because they determine exactly what each estimate represents and how uncertainty should be interpreted.
General statistical interpretation should keep three questions separate: what was measured, how groups were formed, and how uncertainty was quantified. Here, the measurement is survey answers; groups were defined by acceptance or declination; and a 95% confidence interval was specified as the dispersion measure. The record does not include the numerical results needed to assess the size, direction, or precision of a comparison. The design and reporting information therefore allow a cautious description of the study’s structure, but not a quantitative conclusion about its primary outcome.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome title refers broadly to “Answers to Survey Questions,” and the description lists several survey topics: baseline characteristics, vaccine eligibility, and attitudes toward vaccination. The registry lists one outcome measure but does not identify the individual questions, designate a single primary survey item, or explain how the question-level results were organized. It also does not report a multiplicity strategy.
Multiplicity is a general statistical concern that arises when many outcomes or comparisons are assessed. The more tests performed, the greater the chance that at least one result may appear notable by chance, unless the analysis accounts for the number and structure of the tests. This does not establish that multiple testing occurred in this study; the registry record does not provide enough detail to determine that. It also does not report an adjustment method or a hierarchy for interpreting survey results.
The outcome description says all enrolled patients completed a survey. However, completion of a survey does not establish that every question was answered or that every respondent was included in every analysis. Item-level missingness, exclusions, and the handling of incomplete answers are not reported in the registry record. The record does not define the responder denominator for each percentage.
The analysis population is also not described beyond the enrolled patients and the comparison of those who accepted or declined vaccination. There is no reported accounting of eligibility, exclusions, or participants included in each outcome calculation. Although enrollment is listed as 170, the record does not state the group-specific analysis denominators for the primary endpoint. These omissions limit the ability to assess representativeness, missing-data bias, or whether the survey comparison applies to all enrolled patients.
The registry lists zero analyses and does not report a detailed statistical plan. As a result, it is not possible to determine which comparisons were prespecified, whether any were exploratory, or how missing responses and multiple survey questions were treated.
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 |
|---|---|---|---|
| Subjects Who Received the Herpes Zoster Vaccine | 0 | 100 | 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 |
|---|---|
| Subjects Who Received the Herpes Zoster Vaccine | 11 of 100 |
| Subjects Who Declined the Herpes Zoster Vaccine | 0 of 0 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Subjects Who Received the Herpes Zoster Vaccine | Subjects Who Declined the Herpes Zoster Vaccine |
|---|---|---|---|
| Injection Site Reaction | Skin and subcutaneous tissue disorders | 11 of 100 | 0 of 0 |
The registry’s serious-adverse-event entries list 100 at risk and 0 affected for subjects who received the herpes zoster vaccine. For other adverse events, it lists 100 at risk and 11 affected in that group. For subjects who declined vaccination, the record lists 0 at risk and 0 affected for both event categories. Death counts are not reported in the registry record.
These figures should be read as registry entries, not as a full safety comparison. The record does not explain why the declined group has zero at risk, specify the observation period for adverse events, define the other-event category, or describe how events were collected and attributed. It also does not report the clinical details or severity of the 11 other events.
The serious-event count is distinct from the other-event count, and the entries should not be combined into a new total. The zero serious-event entry does not establish that no events occurred outside the registry’s stated category or observation process. Likewise, the comparison cannot be interpreted as evidence of a difference in risk because the groups were not randomized and the registry does not give comparable at-risk denominators for the declined group.
In general, adverse-event counts require context about definitions, follow-up, completeness, and exposure. The registry record does not report those details sufficiently to make a broader safety assessment.
12. What the Result Does, and Does Not, Mean
The registry documents a completed, nonrandomized study intended to increase herpes zoster vaccination through eligibility screening and nurse administration in a General Eye Clinic. It describes a survey of baseline characteristics, eligibility, and attitudes, with responses compared between people who chose vaccination and those who declined. This provides a clear outline of the clinical setting and the intended descriptive comparison.
The record does not report the survey percentages, confidence-interval limits, or analyses. It therefore does not show the direction or magnitude of any difference in survey responses. The stated purpose concerns increasing vaccination rate, but the registry does not provide a numerical estimate of vaccination uptake or a comparison that quantifies an increase. No conclusion about the size or precision of an uptake change can be drawn from the posted results.
Even if response differences were reported, the comparison would remain nonrandomized. Patients’ decisions determined their group, so differences between those who accepted and declined could reflect factors other than the clinic workflow. A survey comparison can describe associations among the observed groups, but it does not by itself demonstrate that screening, administration by a nurse, or vaccination caused those differences.
The record’s adverse-event entries provide limited counts, with no serious events listed among 100 at risk in the vaccinated group and 11 other events among 100 at risk. For the declined group, the corresponding entries list zero at risk and zero affected. These figures do not supply a complete or balanced safety comparison, and deaths are not reported.
In short, the study record describes an implementation approach and a patient-choice comparison, but it does not provide the numerical primary-outcome results needed to judge the survey findings or quantify a change in vaccination. The distinction between an intended service goal and the registered survey endpoint is essential to interpreting what the record can establish.
13. Why This Trial Matters Statistically
This study is statistically useful as an example of the difference between an implementation goal and a registered outcome. The stated aim was to increase vaccination through screening and on-site administration. The registered primary measure is survey answers compared across people who accepted and declined. These questions are related, but they are not interchangeable: a survey comparison does not itself quantify a change in vaccination rate.
The design also illustrates why group formation matters. When patients choose whether to receive an intervention, the resulting groups may differ in ways that affect both their survey responses and their decisions. A comparison can still be informative descriptively, but its interpretation should not be confused with a causal estimate from randomized assignment. Recognizing that distinction is important when translating clinic experience into evidence about an intervention.
Reporting details are equally important. The registry identifies a percentage outcome and a confidence-interval format, but does not post the estimates, interval limits, question-level definitions, or analysis populations. Without those elements, readers cannot assess magnitude, precision, missingness, or the handling of multiple survey questions. A clearly stated outcome type is not a substitute for numerical results and methods.
The record’s planning assumptions also show why planning calculations must be kept separate from observed findings. A planning illustration depends on its assumptions and is not observed power or evidence that an effect was found. Here, the actual registry entry does not report primary-outcome results that would allow a reader to evaluate an observed effect.
These features make the study a useful case for careful statistical reading: distinguish intention from measurement, description from causal inference, and planning from analysis. Those distinctions help prevent a plausible clinical workflow from being mistaken for a demonstrated numerical effect.
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 interpreting the primary outcome is that the registry record does not report its numerical results. It names survey answers as the outcome and specifies a confidence-interval format, but gives no percentages, interval limits, or analysis results. The size, direction, and precision of any observed comparison therefore cannot be assessed.
The study is nonrandomized, and patients were grouped according to whether they chose vaccination. This allows selection differences between acceptors and decliners. The record does not report an adjusted comparison or describe methods to address confounding, so the group contrast cannot be interpreted as an isolated effect of the vaccination workflow.
The registered outcome is broad. Although the survey topics are described, the registry does not list specific questions, response options, or a definition of the responder denominator for each percentage. It does not explain how many question-level comparisons were made or whether a multiplicity strategy was used. The record says all enrolled patients completed a survey, but item-level completeness and handling of missing answers are not reported.
The implementation aim and the primary endpoint are not identical. The stated purpose is to determine whether vaccination rate would increase, while the listed outcome compares survey answers by vaccination choice. The registry does not report a numerical uptake result or an explicit comparison over time. This limits assessment of the stated service goal.
Finally, the adverse-event entries lack key context, including event definitions, observation period, collection procedures, and a comparable at-risk group for patients who declined. Deaths are not reported in the registry record. These specific reporting gaps constrain safety interpretation as well as interpretation of the survey outcome.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Increasing Use of the Vaccine Against Herpes Zoster/Shingles at NYULMC and Bellevue Hospital — NCT01483378.
- Registry record last updated 2013-08-09; status last verified 2013-08.
- Results first posted 2013-08-09.
- 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 a completed, nonrandomized study sponsored by NYU Langone Health, with an enrollment of 170. Its title names NYULMC and Bellevue Hospital. The study aimed to increase herpes zoster vaccination by screening patients for eligibility and having a nurse administer the vaccine in a General Eye Clinic.
The registered primary outcome is survey answers, expressed as a percentage of responders with a 95% confidence interval. The survey covered baseline characteristics, vaccine eligibility, and attitudes, and results were intended to be compared between patients who accepted and declined vaccination. The recorded outcome timeframe is January 9, 2012 to February 12, 2012.
The registry lists zero analyses and does not report numerical survey results. The comparison is based on patient choice rather than random assignment. Serious-adverse-event entries list 0 affected among 100 at risk in the vaccinated group; other-event entries list 11 affected among 100 at risk. The declined group has zero listed at risk and zero affected in both categories. Deaths are not reported in the registry record.