Effectiveness of BNT162b2 Formulations Using State Vaccine Registry and Insurance Claims Data: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effectiveness of BNT162b2 Formulations Using State Vaccine Registry and Insurance Claims Data (NCT06199934), a registered phase not stated study. The primary outcome is Number of Participants COVID-19 Diagnosis.

2. Clinical Question

3. Trial Design

NCT06199934 is listed as a completed study sponsored by Pfizer. Its title describes an assessment of BNT162b2 formulations using state vaccine registry and insurance claims data. The brief summary says the study relied on existing data from different health data sources and did not enroll participants. The registry lists a start date of 2023-09-11 and a primary completion date of 2024-07-31.

The comparison is between BNT162b2 recipients and eligible people who did not receive BNT162b2. The record explicitly indicates that this is not a randomized comparison; allocation is not stated, and the arms are not a like-for-like control comparison. This matters because group differences may reflect characteristics related to vaccination or data capture, in addition to any association with the intervention. The registry record does not describe adjustment methods that would address such differences.

The primary outcome is the number of participants with a COVID-19 diagnosis. Its timeframe runs from FDA authorization or approval of BNT162b2 through the end of follow-up, with a maximum of 6 months. The record also lists secondary outcomes covering outpatient, inpatient, and emergency department encounters; COVID-19 critical illness; non-COVID-19 respiratory infection; negative control outcomes; hospitalization costs; and length of stay.

The registry lists enrollment of 19853610, while the summary describes use of existing data rather than recruitment. The record does not explain the enrollment figure's relationship to the analysis populations. It lists 16 outcome measures and 0 analyses. Thus, the design and intended measures are described, but comparative results and details of the statistical analysis are not reported in the registry record.

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: A total of 19853610 participants were enrolled this study.

Overall Study

Analysis population for the primary outcome, as defined in the registry: Analysis population included all eligible participants whose data were retrieved and observed in this study.

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: Analysis population included all eligible participants whose data were retrieved and observed in this study.

6. Primary Endpoint

The registry lists the primary outcome as Number of Participants COVID-19 Diagnosis, measured over From date of FDA authorization/approval of BNT162b2 until end of follow-up (maximum of 6 months).

The primary endpoint is the number of participants diagnosed with COVID-19. It is a count of people with the outcome, rather than a measure of diagnosis severity, duration, or the total number of episodes. The stated population comprises eligible participants whose data were retrieved and observed in the study. Follow-up begins at FDA authorization or approval of BNT162b2 and continues until the end of follow-up, for a maximum of 6 months.

Counting participants with a diagnosis can provide a straightforward way to describe how often the outcome was observed in the study population. In a comparison, however, counts alone do not establish whether groups differed in risk: interpretation also depends on the relevant group sizes, follow-up, and the analysis used. The registry record does not report group-specific endpoint counts, comparative estimates, confidence intervals, or statistical tests. It therefore does not permit an assessment of the size or precision of a difference in this endpoint.

The registry also does not explain the diagnostic criteria, how diagnoses were identified across data sources, or whether and how repeat diagnoses were handled. Those details would help readers assess what the count represents and whether outcome ascertainment was comparable between groups. The endpoint is relevant to the study's stated interest in COVID-19 outcomes, but its definition and the absent comparative results limit what can be concluded from the record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a study using existing health data rather than participant recruitment. Its title refers to state vaccine registry and insurance claims data, and its summary refers more generally to different health data sources. The record does not name the specific sources or describe how records were linked. It also does not report the statistical analysis methods used to estimate comparative outcomes.

What does a count measure?

The primary endpoint is the number of participants diagnosed with COVID-19. A count records how many people met the outcome definition; it does not, on its own, express the chance of an outcome in a group. For a meaningful group comparison, the number of people observed and the time during which outcomes could be captured are also relevant. The registry record does not report the group-specific counts or denominators needed to interpret the primary endpoint comparatively.

The listed secondary measures span healthcare encounters, illness, costs, and length of stay. These outcomes do not all represent the same kind of quantity. For example, a count of participants with an encounter differs conceptually from total hospitalization costs or average length of stay. The record lists these measures but does not provide their analysis specifications or results.

Why does the comparison design matter?

The listed groups are BNT162b2 recipients and eligible people who did not receive it. The record states that allocation is not stated and that the comparison is not randomized or like-for-like. In general, random assignment can help balance characteristics between groups, while a nonrandomized comparison may reflect differences in who enters each group. Statistical adjustment can sometimes account for measured differences, but it cannot automatically resolve unmeasured differences. The registry record does not report whether adjustment was used or which factors were considered.

How should uncertainty be read?

In general, a confidence interval expresses a range of values compatible with the observed data under a specified statistical model. A narrow interval indicates greater statistical precision than a wide one, while neither width nor location alone addresses all sources of bias. No confidence interval or effect estimate for the primary endpoint is reported in the registry record, so its precision cannot be evaluated.

In general, over-dispersion occurs when observed variability exceeds what a statistical model assumes. It can make standard errors too small if the model does not account for that extra variability. The record gives no dispersion estimate or analysis model for the primary outcome, so it is not possible to say whether over-dispersion was assessed or relevant to the reported analysis.

What do the planning assumptions represent?

The record describes a sample-size planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It describes planning for stated fractions of the observed effect. Such calculations are planning illustrations, not observed power and not evidence that an effect was detected. The registry record does not report the resulting sample-size values or the study's own sample-size justification. It also does not establish that the planning illustration was used to design the study.

The record lists 0 analyses and gives no comparative outcome estimates. Therefore, there are no posted statistical results to interpret or recalculate. The statistical methods that were actually applied, including model choice, covariate handling, uncertainty estimation, and any sensitivity analyses, are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 16 outcome measures, including a primary measure and secondary outcomes involving healthcare encounters, illness, negative controls, costs, and length of stay. Considering multiple outcomes can raise a multiplicity question: when many statistical tests are conducted, the chance of at least one apparently unusual result can increase. In general, a prespecified testing strategy or adjustment can help readers interpret multiple comparisons. The registry record does not report a multiplicity plan, whether any adjustment was used, or analysis results for the listed outcomes.

Missing-data handling is also not reported in the registry record. The summary says that existing data from different health sources were used, but it does not describe missing values, incomplete records, loss of follow-up, or how these issues were handled. It is therefore not possible to assess whether missingness could have affected the observed groups or outcomes.

The primary population is described as eligible participants whose data were retrieved and observed. The record does not give analysis-specific population counts, explain exclusions, or state how eligibility was operationalized across sources. Although enrollment is listed as 19853610, the relationship between that registry field and the populations used for individual outcomes is not explained. It should not be interpreted as an outcome-specific denominator.

The registry record also does not report whether analyses were conducted in subgroups or whether any interim analyses occurred. These details, along with multiplicity procedures and missing-data methods, are not reported in the registry record. Because the record lists 0 analyses and does not post outcome estimates, these omissions prevent evaluation of the statistical handling of the outcomes and analysis populations.

11. What the Result Does, and Does Not, Mean

The record establishes that the study was designed to examine BNT162b2 formulations using existing health data, with a primary measure counting participants diagnosed with COVID-19 during follow-up. It also describes a comparison between vaccine recipients and eligible people who did not receive BNT162b2, and lists additional clinical and healthcare-use outcomes.

What the record does not establish is the size or direction of any association. It does not report primary or secondary outcome estimates, group-specific counts, confidence intervals, or tests. The listed enrollment and outcome definitions cannot replace those results. The absence of reported estimates means the registry record does not answer whether the groups differed or how precisely any difference was estimated.

Nor does the record establish that there was no effect. A missing result is not evidence of a null result. Likewise, the listed secondary outcomes do not demonstrate findings, and the zero values in the adverse-event group listing do not establish that no adverse events occurred. They describe entries in the registry record, not a complete clinical safety assessment.

Even if comparative estimates were available, the nonrandomized design would require careful interpretation. The record cautions that the comparison arms are not like-for-like and does not report adjustment methods. In general, differences between groups in characteristics, care seeking, or data capture can affect observational comparisons. The record does not provide enough information to assess how these issues were handled.

The appropriate conclusion is therefore limited: the registry documents a completed study, its intended data-based comparison, and its outcome measures, but does not report the results needed to quantify effectiveness or precision. It also does not provide enough methodological detail to assess all potential sources of bias.

12. Why This Trial Matters Statistically

This study illustrates the distinction between a clearly stated research question and a result that can be evaluated. The registry identifies a primary COVID-19 diagnosis measure, a comparison based on vaccination status, and a broad set of additional outcomes. Yet the record lists 0 analyses and does not report outcome estimates. Without those estimates, readers cannot assess the size, direction, or precision of the association under study.

It also highlights why design information is central to interpretation. The data-based comparison is explicitly not randomized, and the record cautions that the groups are not like-for-like. In general, observational studies can address questions using existing data, but their comparisons may be affected by group differences and by the way outcomes are captured. Clear reporting of eligibility, data sources, adjustment, and sensitivity analyses helps readers judge those concerns. The registry record does not report these details.

The many listed outcomes further make analysis transparency important. In general, when a study examines multiple endpoints, readers need to know which analyses were planned and how results were interpreted across outcomes. The record does not report a multiplicity strategy or comparative results for the outcomes.

Finally, the registry's enrollment field should be read in the context of the summary, which says participants were not recruited and existing data were used. The record does not explain how the enrollment figure relates to the populations contributing to each analysis. That distinction reinforces why outcome-specific denominators and methods matter more than a single registry enrollment entry when evaluating findings.

13. 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 principal limitation for interpreting the registry record is that it does not report comparative outcome results. There are no group-specific counts, effect estimates, confidence intervals, or statistical tests for the primary endpoint. The record lists 0 analyses, so readers cannot assess either the magnitude or precision of the intended comparison.

The design is nonrandomized, and the record says the arms are not a like-for-like control comparison. Allocation is not stated. The registry record does not report methods for addressing differences between vaccinated and unvaccinated groups, so potential confounding cannot be evaluated from the information recorded.

The title refers to state vaccine registry and insurance claims data, while the summary describes different health data sources. Specific sources, record-linkage procedures, diagnostic criteria, and outcome validation are not reported in the registry record. Nor does it explain how differences in data capture across groups or sources were assessed.

Although follow-up is described as starting at FDA authorization or approval of BNT162b2 and continuing for a maximum of 6 months, the record does not describe group-specific observation time, incomplete follow-up, or missing-data handling. The listed enrollment of 19853610 is not connected to outcome-specific denominators, and no such denominators are reported.

The registry lists 16 outcome measures but does not report a multiplicity strategy or analyses. The record also does not explain whether the listed zero adverse-event counts reflect complete safety ascertainment. These limitations mean the registry record alone cannot support a quantitative assessment of effectiveness, precision, or safety.

14. Related Tutorials

15. Related Statistical Calculators

16. Sources

• ClinicalTrials.gov: Effectiveness of BNT162b2 Formulations Using State Vaccine Registry and Insurance Claims Data — NCT06199934.
• Registry record last updated 2025-09-10; status last verified 2025-08.
• Results first posted 2025-09-10.
• 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.

17. Record Summary

NCT06199934 is a completed Pfizer-sponsored study titled “Effectiveness of BNT162b2 Formulations Using State Vaccine Registry and Insurance Claims Data.” The registry lists a start date of 2023-09-11, a primary completion date of 2024-07-31, and enrollment of 19853610. The summary describes use of existing data rather than participant recruitment.

The primary outcome counts participants diagnosed with COVID-19 from FDA authorization or approval through the end of follow-up, for a maximum of 6 months. The listed comparison is between BNT162b2 recipients and eligible people who did not receive it. The record cautions that this is not a randomized, like-for-like comparison.

Sixteen outcome measures are listed, but the registry record reports 0 analyses and provides no comparative outcome estimates or confidence intervals. The statistical analysis methods, missing-data handling, and relationship between the enrollment field and outcome-specific analysis populations are not reported in the registry record.