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 Epidemiological Study of the COVID-2019 in Participating Organizations. (NCT05043142), a registered phase not stated study. The primary outcome is The Incidence of COVID-2019 Cases..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05043142 |
| Phase | Phase not stated |
| Condition | Covid19 |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 3632 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Yuria-Pharm |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned staff of participating organizations. The registry record lists an enrollment of 3632 and names seven organizations in the primary-outcome description. It does not report the characteristics of the staff, eligibility criteria, how participants were selected, or whether every eligible staff member took part. The intended population beyond these organizations is not reported in the registry record.
Intervention
This was a non-interventional study, not a treatment comparison. The listed intervention is an ELISA test for antibodies to COVID-2019. The study description also concerns prevention practices and prophylactics, but the registry record does not identify a single assigned prevention intervention or report how exposure to each practice was measured.
Comparator
There is no single randomized control group. The secondary-outcome descriptions refer to comparing staff with and without a COVID-2019 case and to examining different prevention practices, drug strategies, combinations, and comorbidities. Which groups were actually compared in an analysis, and how those comparisons were adjusted, are not reported in the registry record.
Primary question
The primary outcome concerns the incidence of COVID-2019 cases in participating organizations, expressed as cases per 1000 person. The study’s stated broader aim was to examine relationships between systematic use of prophylactics and the risks of COVID-2019 incidence and serious complications among staff. The registry record does not report the observed incidence, a comparison effect, or an estimate of association, so the primary question cannot be answered from the recorded results.
3. Trial Design
NCT05043142 is recorded as a completed, exhaustive, cross-sectional, non-interventional, multicenter retrospective epidemiological study. Its title and description concern COVID-2019 incidence and prevention methods among staff of participating organizations. The study start date is 2021-03-16, and the primary completion date is 2021-06-23. The registry record lists an enrollment of 3632.
The primary-outcome description names SI National Institute of Phthisiology and Pulmonology named after F.G. Yanovsky, Yuria-Pharm LLC, Infuzia PJSC, Institute Hyalual LLC, Medical Center M.T.K. LLC, InterChem SLC, and Diatom LLC. The record does not describe how the organizations or staff were selected, how complete the retrospective records were, or what criteria defined a COVID-2019 case.
The listed intervention is an ELISA test for antibodies to COVID-2019, classified as a diagnostic test. That listing does not make the study a randomized test of the assay or of a preventive treatment. No allocation method or like-for-like control comparison is reported. The registry record describes prevention practices and prophylactic drug strategies as subjects of interest, but does not provide a complete exposure definition or say which practices participants actually used.
The record lists 39 outcome measures and reports no analyses in its analysis count. Secondary outcomes include case severity, prevention methods among staff with and without a case, relationships between prevention methods and case occurrence, comorbidities and case occurrence, changes in comorbidity course, and prophylactic strategies and severe cases. These listed questions do not establish that corresponding analyses or results were reported. The registry record does not report a statistical analysis plan, a sample-size justification, interim analyses, or a detailed participant-flow account.
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 | Cross-sectional Study on COVID-19 |
|---|---|
| STARTED | 3632 |
| COMPLETED | 3443 |
| NOT COMPLETED | 189 |
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 One |
|---|---|---|
| Participants analysed | 3443 | |
| Age, Continuous | years | 40.62 (SD 11.954) |
| Sex: Female, Male: Female | Participants | 1978 |
| Sex: Female, Male: Male | Participants | 1465 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: Ukraine | participants | 3443 |
| Weight | kg | 75.97 (SD 16.374) |
| Height | cm | 171.11 (SD 9.140) |
| Number of people in the household | person | 2.88 (SD 1.250) |
| Blood group: I (Type O) | Participants | 935 |
| Blood group: II (Type A) | Participants | 1231 |
| Blood group: III (Type B) | Participants | 607 |
| Blood group: IV (Type AB) | Participants | 290 |
| Blood group: Not known | Participants | 380 |
| Presence of bad habits: Present | Participants | 973 |
| Presence of bad habits: Absent | Participants | 2470 |
| Tobacco smoking / use of other nicotine products | Participants | 875 |
| Alcohol consumption | Participants | 343 |
| Frequency of alcohol consumption: Almost everyday (more than 4 tomes a week) | Participants | 8 |
| Frequency of alcohol consumption: Rarely (less than 2 times a week) | Participants | 301 |
| Frequency of alcohol consumption: Often (more than 2 times a week) | Participants | 28 |
| Frequency of alcohol consumption: Everyday | Participants | 6 |
| Frequency of alcohol consumption: No | Participants | 3100 |
| Other bad habits | Participants | 12 |
| Physical activity: very active (intense physical activity 6-7 days a week) | Participants | 394 |
| Physical activity: slightly active (easy exercises 1-3 times a week) | Participants | 1357 |
| Physical activity: sedentary (easy / no exercise, sedentary work) | Participants | 431 |
| Physical activity: extremely active (intense physical activity everyday) | Participants | 107 |
| Physical activity: moderately active (training / sports 3-5 times a week) | Participants | 1154 |
6. Primary Endpoint
The registry lists the primary outcome as The Incidence of COVID-2019 Cases., measured over 1 visit from March 2021 till June 2021.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | COVID-2019 cases per 1000 person |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “The Incidence of COVID-2019 Cases.” Its stated unit is COVID-2019 cases per 1000 person, and its timeframe is “1 visit from March 2021 till June 2021.” The registry record describes the outcome as incidence in participating organizations by which study subjects are employed. It does not provide a numerical incidence result, a denominator definition, or details of the case-ascertainment procedure.
In general, an incidence measure is intended to describe the occurrence of new cases in a population over a defined period. Expressing a rate relative to a population or person-time denominator can make occurrence easier to compare across groups of different sizes or observation duration. The meaning of this particular rate depends on how “person” was defined, whether observation time varied, and how cases and the observation window were established. Those details are not reported in the registry record. The endpoint’s unit says “per 1000 person,” but the record does not clarify whether the denominator is people at risk, person-time, or another quantity.
An incidence endpoint is relevant to the stated epidemiological aim because the study concerns the occurrence of COVID-2019 cases among staff. It is not, by itself, evidence that a prevention method caused any difference in occurrence. For that interpretation, the exposure definitions, group comparability, outcome ascertainment, and analysis would also matter. The registry record does not report those results or methods in enough detail to assess them.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a study question, population setting, primary outcome, and several secondary questions, but it does not report numerical outcome results. In particular, no observed incidence estimate, comparison estimate, confidence interval, or p-value is included in the registry record recorded for this study. Therefore, the posted information does not establish the direction, size, or precision of any relationship between prevention practices and COVID-2019 cases.
The study is described as retrospective, cross-sectional, and non-interventional. Those design features matter when interpreting associations. In general, observational comparisons can reflect differences between people who used different prevention practices, rather than an effect caused by the practice itself. Factors related to both prevention behavior and case risk could influence an association. The record lists comorbidities among the questions of interest, but does not report whether these or other factors were measured or accounted for in analyses.
The secondary outcomes describe several possible comparisons: staff with and without a COVID-2019 case, severity, prevention methods, comorbidities, and strategies or combinations of prophylactic drugs. Listing a planned or intended outcome is not the same as reporting an estimate for it. The registry record does not show which comparisons were performed, how exposure groups were defined, or whether estimates were adjusted. Its analysis count is 0, so the recorded information does not document analyses in that registry field.
Precision cannot be evaluated without an estimate and its uncertainty interval. In general, a confidence interval conveys a range of values compatible with the data and the specified statistical procedure; a narrow interval indicates greater precision than a wide one, all else equal. No interval is reported in the registry record, so neither precision nor compatibility with different effect sizes can be assessed. The enrolled number alone cannot substitute for an outcome estimate or its uncertainty.
The record’s planning note describes sample-size illustrations based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For time-to-event settings, it specifies total events; for other settings, participants per arm. These are planning assumptions, not observed study results or observed power. The effect and resulting planning values are not reported in the registry information used for this interpretation. The note also does not establish that the study itself used these assumptions to set enrollment.
Accordingly, the most defensible interpretation is descriptive: the registry documents a completed epidemiological study with incidence and prevention-related questions, but does not provide results adequate to quantify those relationships. The sponsor’s own analysis is not reported in the registry record, so no sponsor result can be compared with a recalculation. The registry record’s completion status should not be mistaken for evidence that results were posted or that the stated questions were resolved.
9. Statistical Methods Explained
The registry describes an observational epidemiological study, rather than a randomized comparison. Statistical methods can still summarize rates and associations in such data, but the interpretation depends on the design, outcome definitions, exposure measurement, and analytic choices. The registry record does not report the detailed statistical methods used, so the explanations below are general and do not attribute a particular model or procedure to this study.
What does “cross-sectional” imply?
In general, a cross-sectional study characterizes people, exposures, or outcomes in a defined observation context. A retrospective study uses information about events or measurements that occurred before the study assessment or analysis. These labels do not, by themselves, establish when a prevention practice began relative to infection, how long participants were observed, or whether every outcome was captured. For this study, the stated timeframe is “1 visit from March 2021 till June 2021,” but the registry record does not explain the visit schedule or the observation window used for each person.
What is an incidence rate?
In general, incidence describes new cases arising in a population over a specified interval. A rate may use person-time to account for differing observation durations; a cumulative risk instead uses people at risk over a stated period. The distinction affects both the denominator and the interpretation. The primary outcome’s unit is “COVID-2019 cases per 1000 person,” but the denominator construction is not reported in the registry record. It is therefore not possible to determine from the record whether this is a person-time rate or another rate convention.
A rate estimate is usually interpreted alongside uncertainty. In general, a confidence interval expresses uncertainty under a statistical model and procedure, rather than guaranteeing that the true value lies within the interval. Its width is influenced by the amount of information and the variability of the data. No primary rate estimate or confidence interval is reported in the registry record. Thus, its magnitude and precision cannot be described.
Why can comparisons be difficult?
General observational comparisons may be affected by confounding: a characteristic related to both an exposure and an outcome can make their association differ from the causal effect of the exposure. For example, if groups using different prevention practices differ in health status, work circumstances, or other measured or unmeasured features, the raw case frequencies may not isolate the prevention practice’s contribution. The registry record mentions comorbidities as secondary questions but does not report a confounder set, adjustment method, or adjusted results.
Exposure measurement also matters. The study description refers to systematic use of prophylactics, and secondary outcomes refer to different strategies and drug combinations used at any time from March 2020. In general, a clear analysis needs definitions of the relevant practice, the exposure period, consistency of reporting, and how changes in practice are handled. Those details are not reported in the registry record. Retrospective measurement can also be affected by incomplete records or recall, but the record does not describe the data sources or their completeness.
What does over-dispersion mean?
In general, count outcomes are sometimes analyzed with models that assume a particular relationship between the average count and its variability. Over-dispersion means that the observed variability is greater than that assumed by a simpler model. If it is ignored, estimated uncertainty can be too small, making results appear more precise than they are. The choice of a count model, any assessment of over-dispersion, and any alternative variance method are not reported in the registry record. This is a general consideration, not a claim that over-dispersion was present in this study.
How should multiple outcomes be considered?
The registry lists 39 outcome measures, including the primary incidence outcome and secondary questions about severity, prevention practices, comorbidities, and prophylactic strategies. In general, examining many outcomes or comparisons can increase the chance of finding at least one apparently notable result by chance if each is tested separately. Multiplicity methods may control an error rate or define a hierarchy of questions, but they can affect interpretation and precision. The registry record does not report a multiplicity strategy, a prespecified testing hierarchy, or which outcomes were analyzed.
The record’s planning note describes illustrations using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It says time-to-event illustrations use total events and other illustrations use participants per arm, with the effect to detect expressed as a fraction of the observed effect. In general, such calculations depend on the assumed effect and design conditions. They are planning illustrations, not evidence of the study’s realized power. The registry record does not report a sample-size justification or the underlying effect and illustration values.
What can be concluded from the methods information?
The registry record supplies design labels and outcome descriptions, but not enough detail to reproduce or evaluate a statistical analysis. The model, denominator, missing-data handling, analysis populations, adjustment strategy, and treatment of repeated or clustered observations are not reported in the registry record. General statistical explanations cannot fill those reporting gaps, and no numerical conclusion should be inferred from the design description alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 39 outcome measures, including the primary incidence endpoint and multiple secondary questions. When many outcomes or comparisons are examined, some results can appear notable by chance. In general, a study may address this by prespecifying a hierarchy, adjusting for multiple testing, or treating secondary analyses as exploratory. The registry record does not report which approach, if any, was used. It also does not identify the set of comparisons actually analyzed; its analysis count is 0.
Missing-data methods are important because incomplete outcome, exposure, or covariate information can affect estimates. In general, assessment requires knowing which variables were incomplete, how much information was missing, why it was missing, and whether the analysis used complete cases, imputation, weighting, or another method. These details are not reported in the registry record. The record also does not report participant exclusions, loss to follow-up, or an analysis population definition.
Although enrollment is listed as 3632, that figure does not establish how many people contributed data to each outcome or analysis. The registry record does not report denominators for the primary outcome or secondary comparisons. It is also not reported in the registry record whether records from the participating organizations were linked or checked for duplicate entries. Without these details, the completeness and representativeness of each analysis cannot be assessed.
The record does not report interim analyses, a statistical analysis plan, or procedures for handling multiple comparisons and missing data. These absences limit assessment of whether the reported questions were prespecified and how analytic choices might influence estimates. No inference about the actual handling of missingness or multiplicity is warranted.
11. What the Result Does, and Does Not, Mean
The registry record identifies the study’s purpose: to examine COVID-2019 incidence and prevention practices among staff of participating organizations, including stated questions about serious complications, severity, comorbidities, and prophylactic strategies. It also records a completed status, an enrollment of 3632, and a primary outcome defined as incidence in cases per 1000 person. These are descriptions of the registered study, not numerical evidence of an association.
The recorded information does not report the primary incidence value or results for the secondary outcomes. It therefore does not show whether incidence differed across prevention practices, whether any association was large or small, or how precise an estimate might be. It also does not show whether any observed relationship remained after accounting for other characteristics. No conclusion about the direction or magnitude of a treatment or prevention effect can be drawn from the registry descriptions alone.
In general, observational data can identify patterns and generate hypotheses, but an association does not establish that an exposure caused an outcome. Differences in participant characteristics, exposure timing, outcome ascertainment, and incomplete records can affect comparisons. The registry record does not provide enough methodological or result detail to assess those issues for this study.
The listed ELISA antibody test is a diagnostic test, not a randomized preventive intervention. The study’s observational design and the absence of reported estimates mean the registry record cannot establish the effect of the test or of a prophylactic strategy. Nor does the completed status establish that all outcomes were analyzed or that the intended questions have a definitive answer. Interpretation should remain limited to the study’s stated scope and the information actually recorded.
12. Why This Trial Matters Statistically
This study is statistically relevant because it illustrates the distinction between a registered epidemiological question and a reported analysis. The record names incidence as the primary outcome and describes a broader set of questions about prevention practices, severity, comorbidities, and prophylactic strategies. Those questions require clear outcome and exposure definitions and denominators before estimates can be interpreted.
The setting also highlights a general challenge in observational research: groups defined by their prevention practices may differ in other ways that relate to case occurrence. Statistical adjustment can address measured differences under appropriate assumptions, but it cannot automatically remove bias from unmeasured factors or poorly measured exposures. The registry record does not report the adjustment methods or results needed to evaluate this issue.
A rate expressed per person requires a transparent definition of the denominator and observation period. Without that information, readers cannot determine exactly what population quantity the primary outcome represents or compare it confidently with estimates using a different denominator. The record gives a timeframe and unit but does not specify denominator construction.
Finally, the registry lists 39 outcome measures but does not report analyses or numerical results in the information recorded. This makes multiplicity, missing data, and selective availability of results important considerations for readers. In general, transparent reporting of estimates, uncertainty intervals, analysis populations, and methods is necessary to judge both the size and precision of findings. The record’s design and questions can be described, but its statistical conclusions cannot be evaluated without those results.
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 registry record does not report numerical results for the primary or secondary outcomes. This is the central limitation for statistical interpretation: no incidence estimate, association estimate, uncertainty interval, or p-value is available in the recorded information. The registry’s completed status does not substitute for results.
Important design and measurement details are also not reported. These include eligibility criteria, recruitment and selection procedures, case definitions, data sources, the denominator for the incidence rate, and the handling of the observation period. The record does not describe how prevention practices or drug combinations were measured, or how timing of exposure relative to infection was established. These gaps prevent assessment of potential misclassification and the comparability of exposure groups.
The study is described as retrospective, cross-sectional, and non-interventional. In general, this design can be vulnerable to confounding and temporal ambiguity when evaluating relationships between prevention practices and outcomes. The record does not report adjustment methods or enough information to determine whether measured factors were considered. Although comorbidities are listed among secondary questions, their definitions and analytic role are not described.
The enrollment figure does not show the denominator available for each outcome or whether the enrolled staff represent the organizations’ eligible populations. The registry record does not report missing-data extent or handling, participant exclusions, analysis populations, or data completeness. It also lists 39 outcome measures without reporting a multiplicity approach or which comparisons were performed. These limitations leave both risk of bias and precision difficult to assess.
Finally, the record does not report a statistical analysis plan, sample-size justification, or interim-analysis procedures. Its planning note describes illustrations, but those assumptions do not establish how enrollment was chosen or what analyses were conducted. The limitations arise from registry reporting gaps; they should not be taken as proof that particular procedures were or were not used outside the registry record.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Epidemiological Study of the COVID-2019 in Participating Organizations. — NCT05043142.
- Registry record last updated 2021-10-01; status last verified 2021-09.
- Results first posted 2021-10-01.
- 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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17. Record Summary
NCT05043142 is a completed, retrospective, cross-sectional, non-interventional, multicenter epidemiological study sponsored by Yuria-Pharm. The record lists an enrollment of 3632, a start date of 2021-03-16, and a primary completion date of 2021-06-23. It concerns COVID-2019 incidence and prevention practices among staff of participating organizations.
The primary outcome is incidence of COVID-2019 cases, with a stated unit of cases per 1000 person and a timeframe of “1 visit from March 2021 till June 2021.” An ELISA test for antibodies to COVID-2019 is listed as a diagnostic test. Secondary questions include severity, prevention practices, comorbidities, and prophylactic strategies. The registry lists 39 outcome measures and an analysis count of 0.
Numerical primary and secondary results, analysis methods, denominator details, missing-data procedures, and multiplicity methods are not reported in the registry record. The available record therefore describes the study and its questions but does not provide estimates with which to assess incidence or prevention-related associations.