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 Zinc and/or Probiotic Supplementation of Rotavirus and Oral Polio Virus Vaccines (NCT01616693), a randomized phase 4 study. The primary outcome is Number/Percentage of Subjects With Immune Response to Rotavirus Vaccine.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01616693 |
| Phase | Phase 4 |
| Condition | Immunity to Oral Rotavirus Vaccine, Immunity to Oral Polio Vaccine, Shedding of Oral Rotavirus Vaccine |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 620 |
| Arms in the primary outcome | n/a |
| Lead sponsor | PATH |
| Results posted | Yes |
2. Clinical Question
Population
Infants enrolled at 5 weeks of age and living in urban Vellore, India. The registry record describes the study population but does not report further eligibility details in the record.
Intervention
Daily zinc and probiotic supplements, given alongside rotavirus vaccine and trivalent oral polio vaccine. The probiotic is identified as Lactobacillus rhamnosus GG, and the zinc dose is 5 mg daily.
Comparator
The four groups received zinc and probiotic, zinc alone, probiotic alone, or placebo. All groups also received rotavirus vaccine and trivalent oral polio vaccine.
Primary question
Did supplementation change the number or percentage of participants meeting the registry’s definition of an immune response to rotavirus vaccine? The primary outcome results needed to answer this are not reported in the registry record.
The primary endpoint concerns an antibody response after rotavirus vaccination. The registry defines response using serum anti-rotavirus VP6 IgA: either antibody detection at a concentration of 20 U/ml or more in an individual who was previously seronegative, or a fourfold rise between baseline and 14 weeks of age. The study also assessed immune response to trivalent oral polio vaccine, rotavirus shedding in stool after each vaccine dose, and serious adverse events.
The intervention question has several parts. Comparing the zinc-and-probiotic group with placebo would address the combined supplement strategy. The zinc-alone and probiotic-alone groups permit examination of each supplement against the group receiving neither supplement. Comparisons across all four groups could also explore whether the combination’s observed response differs from the responses in the single-supplement groups. The registry record does not report the planned contrasts or the results of any such comparisons.
Accordingly, the central statistical question is not answerable from the posted primary outcome information. The record specifies the outcome and the randomized groups, but does not give group-level response counts, percentages, effect estimates, confidence intervals, or p-values. The safety counts can be described separately; they do not establish the effect of supplementation on vaccine immune response.
3. Trial Design
This was a phase 4, randomized, quadruple-masked, parallel-group study with an enrollment of 620. Infants were enrolled at 5 weeks of age in urban Vellore, India. The registry lists four supplement groups: zinc and probiotic, zinc alone, probiotic alone, and placebo. Each group also received rotavirus vaccine and trivalent oral polio vaccine.
The supplement regimen was daily for six weeks. The study description says that a single daily dose of the test product began one week before the first study dose of rotavirus and polio vaccines and continued through one week after the second study dose. Rotavirus vaccine doses were given at 6 and 10 weeks of age. The primary immune-response measurement used blood collected when the first rotavirus vaccine dose was given and again four weeks after the second dose, at 14 weeks of age.
Random allocation is intended to make comparison groups similar, on average, with respect to both measured and unmeasured characteristics at the start of a trial. Masking is intended to reduce the chance that knowledge of group assignment influences participant care, outcome assessment, or other trial processes. The registry identifies quadruple masking but does not report which roles were masked or how masking was maintained.
The parallel-group structure means participants were assigned to one supplement group rather than crossing between groups. The four combinations of supplement and placebo could support comparisons of the individual supplements and their combination, but the planned statistical model and the exact comparison strategy are not reported in the registry record. The record also does not describe the randomization procedure, allocation concealment, stratification, or the sample-size justification.
The study status is completed. Its start is listed as 2012-07 and its primary completion as 2013-07. These dates describe the registry record, not the timing of any particular participant’s follow-up. The enrollment figure alone does not show how many participants contributed data to each outcome or analysis; those analysis-specific numbers 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.
Evaluated for Safety
| Stage | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| STARTED | 155 | 155 | 155 | 155 |
| COMPLETED | 154 | 155 | 154 | 155 |
| NOT COMPLETED | 1 | 0 | 1 | 0 |
Reasons for not completing this period:
| Reason | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| Physician Decision | 1 | 0 | 1 | 0 |
Received Both Vaccines
| Stage | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| STARTED | 154 | 155 | 154 | 155 |
| COMPLETED | 141 | 145 | 142 | 136 |
| NOT COMPLETED | 13 | 10 | 12 | 19 |
Reasons for not completing this period:
| Reason | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| Adverse Event | 2 | 0 | 0 | 0 |
| Withdrawal by Subject | 7 | 7 | 8 | 15 |
| Lost to Follow-up | 4 | 3 | 4 | 4 |
Blood Analyzed for Immunogenicity
| Stage | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| STARTED | 141 | 145 | 142 | 136 |
| COMPLETED | 137 | 143 | 136 | 135 |
| NOT COMPLETED | 4 | 2 | 6 | 1 |
Reasons for not completing this period:
| Reason | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|
| Protocol Violation | 4 | 2 | 6 | 1 |
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 | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo | Total |
|---|---|---|---|---|---|---|
| Participants analysed | 155 | 155 | 155 | 155 | 620 | |
| Age, Continuous | weeks | 5.1 (SD .3) | 5.1 (SD .3) | 5.1 (SD .3) | 5.2 (SD .3) | 5.1 (SD .3) |
| Sex: Female, Male: Female | Participants | 75 | 87 | 80 | 84 | 326 |
| Sex: Female, Male: Male | Participants | 80 | 68 | 75 | 71 | 294 |
| Region of Enrollment: India | participants | 155 | 155 | 155 | 155 | 620 |
| Religion: Hindu | Participants | 99 | 96 | 116 | 104 | 415 |
| Religion: Christian | Participants | 5 | 10 | 5 | 6 | 26 |
| Religion: Muslim | Participants | 51 | 49 | 34 | 45 | 179 |
| Type of house: Permanent (pucca) | Participants | 85 | 92 | 93 | 90 | 360 |
| Type of house: Mixed | Participants | 59 | 47 | 52 | 54 | 212 |
| Type of house: Temporary | Participants | 11 | 16 | 10 | 11 | 48 |
6. Primary Endpoint
The registry lists the primary outcome as Number/Percentage of Subjects With Immune Response to Rotavirus Vaccine, measured over from first dose of rotavirus vaccine to 4 weeks after last dose of vaccine.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number or percentage of participants with an immune response to rotavirus vaccine. The registry defines response by serum anti-rotavirus VP6 IgA antibodies. A participant qualified through seroconversion, defined as detection at a concentration of 20 U/ml or more in someone who was previously seronegative, or through a fourfold rise in antibody level between baseline and 14 weeks of age.
Blood was collected at the first rotavirus vaccine dose, when the infant was 6 weeks old, and four weeks after the second dose, at 14 weeks. This makes the endpoint a binary classification for each participant: the person meets the response definition or does not. The count and percentage can then describe the observed frequency of response in a group, while a comparison between groups estimates how those observed frequencies differ.
In general, an antibody endpoint is used as a measurable indicator of immune response. It is not itself a direct measure of every aspect of protection or of clinical illness. The registry’s threshold and rise criteria specify how this particular endpoint was classified; they should not be confused with evidence about other outcomes.
The endpoint description is detailed, but the primary response counts and percentages by group are not reported in the registry record. Nor are an effect estimate, confidence interval, or test result for the primary comparison. Thus, the endpoint can be explained, but its comparative results cannot be interpreted from the posted information.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the trial’s question, allocation structure, endpoint definition, and some safety information. It does not provide the primary immune-response results. In particular, it gives no number or percentage of participants meeting the rotavirus response definition in any of the four supplement groups. There is therefore no posted primary estimate to describe as favoring one group, and no basis in the record for quantifying the size or precision of a between-group difference.
For a binary outcome, a group’s response count and denominator describe how many participants met the endpoint among those evaluated. A comparison may be expressed as a difference in proportions, a ratio of proportions, or another effect measure, depending on the analysis plan. These measures answer related but distinct questions. The registry record does not report which measure was used for the primary comparison, and no primary outcome estimate is available to interpret.
A confidence interval, if reported, would indicate the range of estimates compatible with the data under the specified statistical model and its assumptions. A narrow interval generally indicates more precision than a wide interval, but precision does not establish that a result is important in clinical terms. The registry record does not report a primary confidence interval. It also does not report a primary p-value, so there is no inferential test result to characterize.
The four supplement groups are useful for distinguishing the combined regimen from zinc alone, probiotic alone, and placebo. However, the existence of these groups does not establish that every pairwise comparison was planned or tested. The prespecified comparisons, model, and approach to interpreting the combined intervention are not reported in the registry record. Without those details and the outcome data, it is not possible to distinguish planned analyses from exploratory comparisons.
The record lists secondary outcomes for immune response to trivalent oral polio vaccine, rotavirus shedding after dose 1 and dose 2, and serious adverse events. Their presence shows that the study assessed outcomes beyond the primary rotavirus immune-response endpoint. The outcome values and statistical estimates for these secondary outcomes are not reported in the registry record, apart from the serious adverse-event counts and terms described separately. Those safety figures do not substitute for the missing immune-response result.
Planning illustrations based on an observed effect can help show how a hypothetical future study’s required enrollment would change under different assumed target effects. They are not observed power and do not establish the probability that this completed trial detected an effect. The registry’s sample-size justification and the underlying primary effect estimate are not reported in the registry record. Any planning illustration should therefore be read as a conditional design calculation, not as a result of this trial.
The most defensible interpretation is limited: this was a randomized comparison of four supplement regimens given alongside the same oral vaccines, and the registry defines a binary antibody endpoint for rotavirus response. The posted information does not show whether the groups differed on that endpoint, how large any difference was, or how precisely it was estimated. No conclusion about the primary immune response can be drawn from the registry record alone.
9. Statistical Methods Explained
Statistical methods explain how observations are converted into estimates and how uncertainty is assessed. The registry record describes a randomized parallel-group trial and a binary primary endpoint, but does not report the primary analysis method or results. The concepts below are general explanations, not a description of an unreported protocol.
What does a binary endpoint mean?
A binary endpoint assigns each participant to one of two categories. For this study, the categories are meeting or not meeting the defined immune-response criteria. The response count is interpreted alongside the number of participants assessed. A count without its denominator does not describe the response frequency, and a percentage without a clearly specified analysis population can be difficult to interpret.
For a randomized trial, group-level response frequencies can be compared to estimate an intervention contrast. A difference in proportions describes the absolute separation between groups. A ratio describes the relative frequency. These are not interchangeable summaries, and each needs a confidence interval to communicate statistical uncertainty. The registry record does not report which contrast or statistical model was used for the primary endpoint.
What does randomization contribute?
Randomization assigns participants to groups using a chance-based process. In general, this helps balance baseline characteristics across groups in expectation, including characteristics that are not measured. It does not guarantee identical groups in a particular trial. Descriptions of baseline characteristics can help readers assess the enrolled groups, but the registry record does not report those characteristics in the information summarized for this trial.
Randomization supports causal comparisons when allocation is implemented as intended and the analysis is appropriate to the assignment process. It does not by itself prevent missing outcomes, non-adherence, measurement error, or selective reporting. The record identifies the trial as randomized but does not describe the random sequence method, concealment procedure, adherence, or the handling of participants after randomization.
How should a confidence interval be read?
In general, a confidence interval conveys the uncertainty around an estimated effect under a specified analysis and assumptions. It indicates which effect values are reasonably compatible with the observed data according to that method. It should be read in relation to the effect measure and the range of values that would matter for the scientific question. It does not provide a probability that a particular fixed effect is true, nor does a confidence interval alone establish clinical importance.
No confidence interval for the primary immune-response comparison is reported in the registry record. Consequently, the precision of that comparison cannot be assessed. Even if a test result were available, a p-value alone would not communicate the magnitude or precision of the effect; it would need to be considered together with the estimate, interval, endpoint definition, and analysis plan.
What are the planning illustrations for?
In general, a sample-size calculation specifies an effect the study aims to detect, a significance level, an allocation scheme, and assumptions about the statistical distribution. A planning illustration can then show the number of participants needed under those assumptions. Such a calculation is conditional: changing the target effect or assumptions changes the required sample size. It does not describe the trial’s observed result.
The planning assumptions described for this study use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The illustrations define the target effect as a stated fraction of the observed effect. Those calculations are planning illustrations, not observed power. The registry record does not report the trial’s own sample-size justification, and the primary results needed to assess the observed effect are not reported. The numerical sample-size outputs are not reported in the registry record.
When a planning illustration is based on an observed effect, interpretation also depends on how that observed effect was estimated. In general, an effect estimated in a completed trial can be uncertain, and planning around a single estimate does not remove that uncertainty. A smaller target effect will generally require more information to estimate with similar precision, but no new enrollment figure can be inferred without the relevant calculation inputs and output.
Why do multiple outcomes and comparisons matter?
Multiplicity arises when several outcomes, comparisons, or analyses are examined. In general, conducting many statistical tests can increase the chance that at least one result appears unusual by chance. A study may address this through prespecified primary comparisons, adjustment procedures, or a clearly hierarchical testing plan. Which approach is appropriate depends on the scientific aims and analysis plan.
The record lists six outcome measures and six analyses, alongside the primary endpoint and secondary outcomes. It does not report how the analyses map to outcomes, how many comparisons were planned, whether any multiplicity adjustment was applied, or how results were prioritized. Without that information and the underlying estimates, the statistical meaning of any unreported comparisons cannot be assessed.
These methods concepts clarify what would be needed to interpret the trial’s primary result: group response counts and denominators, a defined contrast, an effect estimate, an uncertainty interval, and a description of the analysis population and multiplicity strategy. The registry record specifies the endpoint but does not report those primary analysis details or results. The statistical interpretation must therefore remain limited to the design and outcome definition that are recorded.
10. Multiplicity, Missing Data and Analysis Populations
Multiplicity, missing outcome data, and analysis populations affect how a trial estimate should be understood. The record identifies a primary rotavirus immune-response endpoint and several secondary outcomes: immune response to trivalent oral polio vaccine, shedding after each of two rotavirus vaccine doses, and serious adverse events. It does not report how many statistical comparisons were planned, whether tests were adjusted for multiple comparisons, or whether any hierarchy was used to prioritize outcomes.
In general, evaluating several outcomes or contrasts creates more opportunities for chance findings. Prespecifying a primary comparison and a multiplicity strategy can help readers distinguish confirmatory analyses from exploratory ones. The registry record does not report the planned comparison strategy or the statistical plan, so the status of individual analyses cannot be determined.
The registry reports enrollment and separate denominators for the serious adverse-event groups, but does not report the number assessed for the primary endpoint in each group, the extent of missing primary outcome data, or reasons for missingness. It also does not describe imputation, exclusions, or sensitivity analyses. These details are important because conclusions can depend on whether outcome availability differed by group or was related to participants’ underlying response.
The analysis population is likewise not reported in the registry record. The record does not say whether the primary analysis included all randomized participants, those who received the intended regimen, or another defined subset. These are general categories of analysis population; no particular approach should be attributed to this trial without documentation. The missing information limits assessment of attrition, possible selection effects, and how closely the analysis reflects the randomized comparison.
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 |
|---|---|---|---|
| Zinc and Probiotic | 5 | 154 | 3.2% |
| Zinc Alone | 3 | 155 | 1.9% |
| Probiotic Alone | 2 | 154 | 1.3% |
| Placebo | 4 | 155 | 2.6% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Zinc and Probiotic | 0 of 154 |
| Zinc Alone | 0 of 155 |
| Probiotic Alone | 0 of 154 |
| Placebo | 0 of 155 |
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 |
|---|---|
| Zinc and Probiotic | 149 of 154 |
| Zinc Alone | 152 of 155 |
| Probiotic Alone | 148 of 154 |
| Placebo | 146 of 155 |
Most frequent serious adverse event terms
| Event term | Organ system | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|---|
| Pneumonia | Respiratory, thoracic and mediastinal disorders | 3 of 154 | 2 of 155 | 1 of 154 | 3 of 155 |
| Bronchiolitis | Respiratory, thoracic and mediastinal disorders | 2 of 154 | 0 of 155 | 1 of 154 | 1 of 155 |
| Meningitis | Nervous system disorders | 0 of 154 | 1 of 155 | 1 of 154 | 1 of 155 |
| Acute febrile illness | General disorders | 1 of 154 | 0 of 155 | 0 of 154 | 0 of 155 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Zinc and Probiotic | Zinc Alone | Probiotic Alone | Placebo |
|---|---|---|---|---|---|
| Cold/runny nose | Respiratory, thoracic and mediastinal disorders | 143 of 154 | 148 of 155 | 140 of 154 | 144 of 155 |
| Cough | Respiratory, thoracic and mediastinal disorders | 130 of 154 | 134 of 155 | 128 of 154 | 130 of 155 |
| Fever | General disorders | 112 of 154 | 117 of 155 | 108 of 154 | 100 of 155 |
| Diarrhea | Gastrointestinal disorders | 38 of 154 | 47 of 155 | 44 of 154 | 31 of 155 |
| Any other illness | General disorders | 31 of 154 | 34 of 155 | 37 of 154 | 26 of 155 |
| Vomiting | Gastrointestinal disorders | 29 of 154 | 29 of 155 | 32 of 154 | 33 of 155 |
Serious events with the highest arm-level rate: pneumonia (1.9%), bronchiolitis (1.3%), meningitis (0.6%), acute febrile illness (0.6%).
The registry reports serious adverse-event counts by supplement group. The Zinc and Probiotic group had 5 participants recorded with a serious adverse event among 154 at risk; Zinc Alone had 3 among 155; Probiotic Alone had 2 among 154; and Placebo had 4 among 155. The recorded number of deaths was 0 in each group.
These are descriptive counts. They do not, by themselves, establish whether the groups differ statistically or whether an event was caused by a supplement or a vaccine. The registry record does not report a comparative safety estimate, confidence interval, or test result. It also does not describe the criteria used to determine whether an event was related to an intervention.
The most frequently listed serious adverse-event terms are Pneumonia at 1.9%, Bronchiolitis at 1.3%, Meningitis at 0.6%, and Acute febrile illness at 0.6%. The registry record does not specify the group-specific denominators or comparison underlying these term percentages in the information reported. They should not be interpreted as intervention-specific risks.
Serious adverse events are not the same as all adverse events. The posted figures do not establish the frequency of non-serious events, the timing or duration of events, or the overall tolerability of each regimen. They also do not resolve whether uncommon harms could have been missed. The safety information is therefore best read as a limited descriptive account of recorded serious events, not as a complete comparative safety analysis.
12. What the Result Does, and Does Not, Mean
The trial’s design addresses a specific research question: whether adding zinc, a probiotic, or both alongside oral rotavirus and polio vaccines changes measured immune responses in infants. The record identifies four supplement groups and defines a rotavirus antibody endpoint. It also records serious adverse-event counts. These details describe what the study set out to assess, but they are not a substitute for its comparative outcome results.
The registry record does not report primary response counts, percentages, estimates, confidence intervals, or p-values. Therefore, it does not show whether any supplement group had a higher or lower observed immune-response frequency than another, nor how large or precise such a difference might be. The listed secondary outcomes are also not reported with results in the registry record, apart from the serious adverse-event summaries.
In general, an antibody response is an immunologic measure. It should not automatically be treated as a direct measure of clinical outcomes, and the registry endpoint description does not establish effects on illness, hospitalization, or other health outcomes. Such outcomes are not reported as results in the record. No claim about the clinical value of a supplement regimen follows from the endpoint definition alone.
The serious adverse-event counts can be described by group, but they do not identify the cause of events or provide a complete account of safety. The record does not report comparative statistical analyses of those counts. The zero deaths recorded in each group is a descriptive observation and does not establish the absence of other serious events or risk.
As a result, the meaning of the posted information is primarily methodological: it documents a randomized, masked comparison and a prespecified-looking antibody definition, while leaving the primary efficacy comparison unavailable in the registry record. The data needed to evaluate effect size, statistical uncertainty, missing outcomes, and multiplicity are not reported. Readers should distinguish this absence of results from evidence that the groups were the same; an unreported comparison cannot establish either similarity or difference.
13. Why This Trial Matters Statistically
Statistically, the study is notable for comparing four supplement combinations while keeping the oral vaccine regimen common to all groups. This structure can, in principle, help separate questions about zinc, probiotic, and their combination. Such separation depends on the planned contrasts and analysis, which are not reported in the registry record.
The primary endpoint is defined at the participant level using a specified antibody criterion and a baseline-to-follow-up comparison. A clear binary definition is important because it determines who is counted as a responder. The registry also specifies the timing of blood collection in relation to the two rotavirus vaccine doses. This makes the intended measurement window interpretable, even though the group-level outcome results are not available in the record.
The trial also illustrates why design details and outcome evidence must be kept distinct. Randomization and masking can strengthen a comparison’s design, but they do not reveal the result. Enrollment of 620 describes the overall study size; without outcome denominators and estimates by group, it does not show the precision achieved for the primary endpoint. Likewise, a planning illustration cannot replace an observed effect estimate.
Finally, reporting of secondary outcomes and serious adverse events raises useful questions about outcome prioritization and multiplicity. Knowing the planned analysis strategy would help clarify how to interpret multiple comparisons, and knowing the analysis populations would help assess missing-data risks. These details are not reported in the registry record. The trial is therefore statistically informative as a design and measurement example, but its primary comparative finding cannot be evaluated from the posted results.
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 interpretation is that the primary immune-response results are not reported in the registry record. Without group-level counts and denominators, effect estimates, or confidence intervals, the primary question cannot be answered and precision cannot be assessed. The record’s detailed endpoint definition does not remedy the absence of the outcome values.
The registry record does not report the sample-size justification, the primary statistical model, the planned contrasts, or the handling of multiple comparisons. It also does not describe the randomization procedure, allocation concealment, which roles were masked, or how masking was maintained. These omissions limit assessment of how the design was implemented and how the analysis relates to the research question.
Analysis-specific participant numbers and missing-data information are not reported for the primary outcome. The record does not state the analysis population, describe exclusions, or explain how missing measurements were handled. It is therefore not possible to assess whether the outcome analyses retained the benefits of randomization or whether incomplete follow-up could affect interpretation.
The study population is described as infants 5 weeks old living in urban Vellore, India. The record does not provide further information about participant characteristics or other settings. Any application to populations beyond the described group would require evidence and context not reported in this registry record.
The safety information is also limited: serious adverse-event counts and selected event terms are reported, but a comparative analysis, causal assessment, and fuller account of non-serious events are not. The registry’s completed status does not fill these reporting gaps. These limitations are specific to the information recorded and do not establish that the analyses or details were absent from other study documents.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Zinc and/or Probiotic Supplementation of Rotavirus and Oral Polio Virus Vaccines — NCT01616693.
- Registry record last updated 2018-12-26; status last verified 2018-12.
- Results first posted 2018-11-30.
- 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
NCT01616693 is a completed phase 4 randomized, quadruple-masked, parallel-group trial with an enrollment of 620. It studied zinc and/or probiotic supplementation alongside rotavirus vaccine and trivalent oral polio vaccine in infants enrolled at 5 weeks of age in urban Vellore, India. The four groups received zinc and probiotic, zinc alone, probiotic alone, or placebo.
The primary outcome was the number or percentage of participants meeting a defined rotavirus antibody-response criterion, assessed using blood collected at baseline and at 14 weeks of age. The registry record does not report the primary outcome results or comparative estimates. It reports serious adverse-event counts of 5, 3, 2, and 4 across the four groups, respectively, with 0 deaths in each group. The record does not provide the analysis details needed to evaluate the primary comparison, missing data, or multiplicity.