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 Histamine Glutamate Antagonism in Stroke (NCT02142712), a randomized phase 2 study. The primary outcome is Modified Rankin Score.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02142712 |
| Phase | Phase 2 |
| Condition | Acute Cerebrovascular Accident, Cerebral Edema |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 3 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Florida |
| Results posted | Yes |
2. Clinical Question
Population
The record concerns acute ischemic stroke and lists acute cerebrovascular accident and cerebral edema as conditions. It does not report detailed eligibility criteria or participant characteristics. The investigators’ stated hypothesis focused on treatment initiation in the first six hours, but the registry record does not establish whether every participant met a particular treatment-window criterion.
Intervention
The listed drugs are diphenhydramine, dextromethorphan, famotidine, and pantoprazole, described alongside current standard of care. The record characterizes diphenhydramine and dextromethorphan as the pathway-modulating treatments of interest, while famotidine and pantoprazole are described in the context of stress ulcer prophylaxis. It does not report outcome data by intervention.
Comparator
The study summary frames the research question as comparing neuroprotective strategies with standard of care. The arm descriptions specify that the listed drugs are given along with current standard of care. The precise allocation and comparison structure among the listed treatments is not reported in the registry record, so a particular pairwise comparison cannot be identified from the available information.
Primary question
The primary outcome is the modified Rankin Scale, assessed at 8 days and 3 months from baseline. The investigators sought to examine whether glutaminergic or histaminergic antagonism could affect short- and long-term disability after acute ischemic stroke. The registry record says follow-up data were not collected because participants did not return; it therefore provides no observed answer about differences in disability.
3. Trial Design
NCT02142712, titled “Histamine Glutamate Antagonism in Stroke,” is recorded as a phase 2, randomized, parallel-design study with no masking. The sponsor is the University of Florida. The registry lists enrollment of 3 and gives both the study start and primary completion as 2014-12; its status is completed. The record does not give more detail about how randomization was performed, how treatment assignments were concealed, or how the study was operationally organized.
The interventions listed are diphenhydramine, pantoprazole, famotidine, and dextromethorphan. Diphenhydramine is described as 12.5 mg BID intravenously or 25 mg BID orally for 4 days, alongside current standard of care. Dextromethorphan is described as 60 mg QID orally for 2 days, for a total of 4 doses, with tube administration if oral administration is not possible. Famotidine is described as 40 mg intravenously BID for 4 days, with a maximum dose of 80 mg/day, for stress ulcer prophylaxis alongside current standard of care. Pantoprazole is described as 40mg intravenously q daily for stress ulcer prophylaxis alongside current standard of care.
The registry record does not explain the exact allocation structure across these interventions or identify a complete set of comparator arms. It also does not report the actual time from stroke onset to treatment for participants. The summary states that the investigators hypothesized a benefit from treatment initiation in the first six hours; that statement describes the research hypothesis, not an observed treatment exposure or result.
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 | Famotidine | Pantoprazole | Diphenhydramine | Dextromethorphan |
|---|---|---|---|---|
| STARTED | 1 | 1 | 1 | 0 |
| COMPLETED | 0 | 0 | 0 | 0 |
| NOT COMPLETED | 1 | 1 | 1 | 0 |
Reasons for not completing this period:
| Reason | Famotidine | Pantoprazole | Diphenhydramine | Dextromethorphan |
|---|---|---|---|---|
| Lost to Follow-up | 1 | 1 | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: The data was not collected since the participants did not come back for follow-ups.
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 | Famotidine | Pantoprazole | Diphenhydramine | Total |
|---|---|---|---|---|---|
| Participants analysed | 1 | 1 | 1 | 3 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | 1 | 0 | 2 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 1 | 1 |
| Sex: Female, Male: Female | Participants | 1 | 0 | 0 | 1 |
| Sex: Female, Male: Male | Participants | 0 | 1 | 1 | 2 |
| Region of Enrollment: United States | participants | 1 | 1 | 1 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Modified Rankin Score, measured over 8 days and 3 months from the baseline.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the modified Rankin Scale (m-RS), a measure of disability and dependence in daily activities after stroke. The record describes an ordinal scale ranging from 0, no symptoms, through 6, dead. Its intermediate categories distinguish increasing limitations, from symptoms without significant disability to severe disability requiring constant nursing care and attention.
This scale is used in stroke research because it captures functional status across a range of outcomes rather than focusing on a single symptom or physiological measurement. As an ordinal outcome, its categories have a natural order, but the distances between neighboring categories should not automatically be treated as equal. Statistical methods should respect that structure when comparing groups.
The listed assessment times are 8 days and 3 months from baseline. Those time points would permit examination of disability at an early follow-up and a later follow-up, but the registry record says the data were not collected because participants did not return for follow-ups. It therefore reports neither the distribution of scores nor an estimated contrast between study groups. A planned outcome definition is not itself evidence of a measured treatment effect.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record does not report observed modified Rankin Scale results. It states that the data were not collected because participants did not return for follow-ups. Without outcome observations, there is no reported group distribution, treatment-effect estimate, confidence interval, or significance test for the primary endpoint. The record also lists 0 analyses. As a result, the available information cannot establish whether disability differed among the interventions or relative to standard care.
The enrollment field reports 3, but that figure cannot substitute for the missing endpoint data. It does not show which participants completed a particular assessment, how participants were assigned, or whether any participant contributed a usable primary outcome. Those details are not reported in the registry record. Nor can a treatment effect be inferred from the investigators’ hypothesis about early treatment or from the fact that the study is marked completed.
The scale’s ordered categories matter to interpretation. A comparison could be expressed in different ways, such as comparing the full distribution across categories or using a chosen summary. Each approach answers a somewhat different question. The registry record does not identify a primary analysis method or give a prespecified contrast, and it does not reduce the outcome’s categories or time points to one comparison. Accordingly, there is no basis in the posted results for choosing among these interpretations.
For safety, the record lists zero serious adverse events and zero other adverse events among the participants reported at risk in each of the Famotidine, Pantoprazole, and Diphenhydramine groups. These sparse counts describe the entries in the registry, not a precise estimate of safety. The corresponding death values are not reported in the registry record. A dextromethorphan adverse-event group is not listed in the available safety entries, so its absence cannot be interpreted as a zero count.
The sample-size material describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It is not a report of observed power, and those assumptions should not be mistaken for the trial’s own design rationale. No observed effect estimates or resulting planning values are reported in the registry record, so a numerical planning conclusion cannot be interpreted from the available information.
Overall, the record documents a study question, intervention descriptions, and an intended disability endpoint, but not an efficacy analysis. The absence of endpoint observations is different from evidence that treatments had equal outcomes. It leaves the treatment comparison unresolved in the registry record.
9. Statistical Methods Explained
Randomization is a design method intended to make treatment groups comparable, on average, with respect to both measured and unmeasured baseline characteristics. It supports causal interpretation when assignment, follow-up, and analysis are appropriately carried out. The registry identifies this study as randomized, but does not report the randomization sequence method, allocation concealment, or the allocation structure among the listed treatments. Those omissions prevent a detailed assessment of how assignment was implemented.
What does the parallel design mean?
In a parallel design, participants are assigned to a treatment group and followed within that group rather than crossing through multiple treatments in sequence. This is a general description of the design type, not a report of specific procedures. Here, the registry also identifies the study as unmasked. In general, lack of masking can affect behavior, care, outcome assessment, or reporting, depending on how outcomes are collected. The record does not describe who assessed the modified Rankin Scale or what procedures were used to limit assessment bias.
How should the primary outcome be analyzed?
The modified Rankin Scale is ordinal: its categories are ordered, but the gap between adjacent categories is not necessarily constant. In general, an ordinal analysis can compare the distribution across all categories, while other approaches may summarize the outcome or define a particular threshold. These choices carry different assumptions and produce different estimands—the precise treatment contrast being targeted. The registry record does not report which approach was planned or used. It also identifies assessment at 8 days and 3 months from baseline, without specifying a primary time point for a single comparison.
A confidence interval, in general, describes the range of effect estimates compatible with the data and the assumptions of a statistical method. Its width reflects precision as well as the amount and variability of information in the data. A p-value, in general, measures how surprising data at least as incompatible with a null hypothesis would be under that hypothesis and the model assumptions. Neither quantity is reported for the primary endpoint. With no collected follow-up data, there is no reported estimate or interval to interpret.
What do the planning assumptions represent?
The record’s sample-size description labels its calculations as a planning illustration based on the observed effect. It specifies a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the intended effect to detect is described as a stated fraction of the observed effect. For time-to-event tables, the description says totals would refer to events; other planning values would refer to participants per arm. These are general calculation conventions, not observed trial findings.
Such an illustration asks how much information a future comparison might require under selected assumptions. It does not show that the study had that amount of information, and it is not “observed power.” Observed power is not a substitute for estimating an effect and its uncertainty. The registry record does not report the observed effect, the selected fractions, or numerical planning results. It also does not report a sample-size justification for the trial’s own design. The illustration should therefore not be read as proof that the trial was adequately or inadequately sized.
Why does over-dispersion matter?
In general, over-dispersion occurs when variability in observed data exceeds what a statistical model assumes. If a model understates variability, its uncertainty estimates may be too small and its tests may appear more decisive than warranted. Methods that allow for extra variation can improve uncertainty estimates when the data and outcome call for them. The registry record does not report an over-dispersion assessment or a fitted model; this general issue cannot be tied to an analysis of this study’s primary outcome.
The record reports 0 analyses and does not provide a statistical analysis plan. Therefore, it is not possible to determine from the registry how missing outcomes, multiple outcomes, repeated assessment times, or the ordinal scale were handled analytically. A sound methods interpretation distinguishes the registered design and outcome definitions from procedures and results that are not reported.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 5 outcome measures and describes the modified Rankin Scale as the primary outcome, with assessments at 8 days and 3 months from baseline. It does not report a statistical analysis plan explaining how those time points were to be handled, or how the other outcomes relate to the primary outcome. The record also indicates that the primary outcome has several categories or time points and was not reduced to one comparison.
Multiplicity is the issue that arises when several outcomes, time points, groups, or statistical tests are examined. In general, conducting more tests can increase the chance of finding an apparently unusual result by chance. Prespecifying a primary contrast and a strategy for secondary comparisons can clarify which findings are confirmatory and how uncertainty should be interpreted. The registry record does not report a multiplicity adjustment, hierarchy, or other strategy. Because no outcome analyses are listed, there are no reported tests to evaluate for multiplicity.
Missing data are central to this record: it explicitly states that primary outcome data were not collected because participants did not return for follow-ups. It does not report how many assessments were missing at each time point, reasons beyond the stated non-return, or any imputation or sensitivity-analysis method. In general, missingness can affect validity when the chance of an outcome being observed is related to participants’ health or outcome values. Without follow-up observations or a documented analysis, the direction and size of any resulting bias cannot be assessed.
The record does not report the analysis population, such as whether all randomized participants were intended for an intention-to-treat analysis, or whether another population was defined. It also does not report exclusions or adherence-based analyses. These are not details that can be inferred from the randomized design alone.
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 |
|---|---|---|---|
| Famotidine | 0 | 1 | 0.0% |
| Pantoprazole | 0 | 1 | 0.0% |
| Diphenhydramine | 0 | 1 | 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 |
|---|---|
| Famotidine | 0 of 1 |
| Pantoprazole | 0 of 1 |
| Diphenhydramine | 0 of 1 |
The registry’s safety entries list Famotidine, Pantoprazole, and Diphenhydramine. For each listed group, serious adverse events are reported as 0 among 1 at risk, and other adverse events are reported as 0 among 1 at risk. These are the recorded counts; they should not be expanded into a general claim about safety or interpreted as precise estimates of event risk.
The record does not report death counts for these groups. It also does not list a dextromethorphan group in the adverse-event entries, so a missing group entry should not be read as a reported zero. No serious adverse event terms are listed. The registry does not describe the event-collection period, definitions, severity grading, or whether events were assessed systematically.
In general, adverse-event counts are interpreted in relation to how many participants were observed, the duration and completeness of safety follow-up, and the rules used to collect events. Small or incomplete safety records can fail to capture uncommon harms. Here, the recorded counts are limited and the primary follow-up problem is documented. They therefore provide only a narrow description of what the registry reports, not evidence that no adverse events could occur.
12. What the Result Does, and Does Not, Mean
This record identifies a clinical question: whether glutaminergic or histaminergic pathway modulation, alongside standard care, might influence disability after acute ischemic stroke. It records a randomized, parallel, unmasked phase 2 study and specifies the modified Rankin Scale at 8 days and 3 months from baseline as the primary outcome. These details explain the intended comparison and outcome, but they do not constitute an estimate of treatment effect.
The key result for interpretation is that the primary outcome data were not collected because participants did not return for follow-ups. No primary-outcome distribution, group contrast, confidence interval, or statistical test is reported. The registry’s enrollment field and completion status do not fill that gap. Without outcome data, there is no basis to say whether disability was better, worse, or similar across interventions.
The safety entries report no events in the listed groups at risk, but the reported information is limited, death counts are not reported, and the dextromethorphan group is absent from those entries. These registry entries should be kept separate from the unanswered efficacy question. Sparse adverse-event entries cannot establish that an intervention is safe, just as missing disability data cannot establish a lack of effect.
The record also does not specify a statistical analysis plan, the exact comparison structure, or the analysis population. Consequently, it is not possible to assess how the researchers intended to handle the scale’s ordered categories, multiple assessment times, or missing outcomes. General statistical principles can explain why these details matter, but they cannot supply the absent trial-specific methods or results.
The appropriate conclusion is limited: the registry documents the study design and intended outcome, while its record does not contain the follow-up outcome data needed to answer the primary question. This is an absence of an interpretable treatment-effect estimate, not evidence for equivalence or for no effect.
13. Why This Trial Matters Statistically
This trial is statistically notable because it illustrates the distinction between a registered research question and an answer supported by outcome data. A randomized design can help make comparisons fair, but randomization alone cannot yield a treatment-effect estimate. The intended outcome must be collected, analyzed, and reported with enough detail to assess both the magnitude and uncertainty of the comparison. In this record, the primary follow-up outcome was not collected.
The planned endpoint also has meaningful statistical structure. The modified Rankin Scale is ordinal, with categories spanning no symptoms through death. Treating such an outcome as a simple continuous measurement may require assumptions about spacing between categories; alternatives can retain the ordered-category structure. The record does not identify which method was planned, leaving the intended estimand unclear even apart from the missing outcome data.
The listed assessment times raise a related issue: an early assessment and a later assessment could tell different parts of the clinical story, and a study needs a clear approach to interpreting multiple time points. The registry does not report how those assessments were to be prioritized or analyzed. With 5 outcome measures listed and 0 analyses reported, the record does not permit assessment of multiplicity or the selectivity of reported findings.
Finally, the entry highlights why missing-data reporting matters. A reason for absent follow-up is recorded, but the extent and handling of missingness are not. Without this information, readers cannot evaluate representativeness, potential bias, or precision. These limitations are important statistical features of the registry record, not a judgment about the biological plausibility of the hypothesis.
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 most direct limitation is the absence of primary outcome data. The registry says participants did not return for follow-ups, and no modified Rankin Scale results are reported. There is therefore no estimate with which to compare the listed treatments, and no uncertainty measure to show how precise such an estimate might have been.
The record’s enrollment field reports 3, but it does not describe the number of participants assigned to each intervention, the number assessed at either time point, or which participants contributed to safety reporting. The adverse-event entries give counts for Famotidine, Pantoprazole, and Diphenhydramine, but do not list a dextromethorphan group. Death counts are not reported. The available safety information is consequently incomplete for interpreting events across all listed interventions.
Although the design is described as randomized and parallel, the registry does not provide the allocation structure, specific comparator assignments, randomization procedures, or masking procedures beyond “none.” It does not report participant characteristics, detailed eligibility criteria, adherence, protocol deviations, or actual treatment timing. The stated first-six-hours hypothesis should not be mistaken for documentation that this timing was achieved.
The registry does not report the statistical analysis plan, analysis population, method for the ordinal endpoint, treatment contrast, missing-data strategy, or multiplicity approach. It gives no detailed accounting of the other outcome measures. These omissions limit assessment of both internal validity and the intended interpretation. The completed status records the study’s administrative status; it does not resolve the missing results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Histamine Glutamate Antagonism in Stroke — NCT02142712.
- Registry record last updated 2015-12-15; status last verified 2015-11.
- Results first posted 2015-12-15.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT02142712 is a completed, randomized, parallel, unmasked phase 2 study sponsored by the University of Florida. The registry lists enrollment of 3 and study start and primary completion in 2014-12. Interventions listed are diphenhydramine, dextromethorphan, famotidine, and pantoprazole, used alongside current standard of care as described in the record.
The primary outcome is the modified Rankin Scale at 8 days and 3 months from baseline. The registry states that outcome data were not collected because participants did not return for follow-ups, and it lists 0 analyses. No treatment-effect estimates are reported. Safety entries give event counts for Famotidine, Pantoprazole, and Diphenhydramine; death values are not reported, and dextromethorphan is not listed in those entries. The record therefore describes the study question and intended outcome but does not provide results that answer the primary comparison.