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 V2 Receptor Effects on Fluid Regulation and Performance (NCT02084797), a randomized na study. The primary outcome is Sweat Sodium Concentration Obtained After the Steady-state Portion of the Trial.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02084797 |
| Phase | NA |
| Condition | Electrolyte Imbalance, Hyponatremia, Hypernatremia |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | Double |
| Enrollment | 10 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Oakland University |
| Results posted | Yes |
2. Clinical Question
Population
Participants undertaking exercise in a study of fluid regulation and performance. The registry record reports an enrollment of 10 and lists electrolyte imbalance, hyponatremia and hypernatremia among the conditions. It does not provide a fuller description of participant characteristics or the analysis population.
Intervention
Manipulation of the vasopressin 2 receptor (V2R) using an antagonist or agonist. The arm description specifies a 30mg Tolvaptan tablet and a 0.2mg DDAVP tablet, each ingested 2 hours before exercise.
Comparator
Placebo, with each participant described as receiving all interventions. The registry record does not give numerical outcome comparisons between placebo, the V2R agonist and the V2R antagonist.
Primary question
Does changing V2R activity during exercise alter sweat sodium concentration, as measured after the steady-state portion of the trial? The stated hypothesis proposes that sweat sodium changes would parallel urine sodium changes under antagonist, agonist and placebo conditions.
The study asks whether arginine vasopressin acting through the V2 receptor is involved in regulating sweat water content and sodium concentration during exercise. The primary focus is sweat sodium concentration; the stated rationale connects it to fluid conservation and to sodium regulation in the kidney. The registry also describes secondary aims concerning running performance and core temperature, as well as secondary outcomes involving urine, blood and saliva sodium concentrations.
These are questions about acute responses under different intervention conditions, not evidence that any intervention improves health or performance. Because the registry record does not report primary or secondary numerical results, it cannot establish the direction or size of any observed differences. It also does not report enough detail to determine how the stated comparisons were analyzed or how precisely they were estimated.
3. Trial Design
The registry identifies this as a completed, randomized, double-masked crossover study, with an enrollment of 10. In a crossover design, participants receive more than one intervention condition, so comparisons can be made within the same participants. This general feature can account for stable differences between individuals, but it does not by itself establish that the intervention sequence, timing or analysis was appropriate. The record states that all study participants received all interventions.
The intervention description names a V2R antagonist, a V2R agonist and placebo. It specifies a 30mg Tolvaptan tablet for the antagonist condition and a 0.2mg DDAVP tablet for the agonist condition, each taken 2 hours before exercise. The registry describes the primary outcome timeframe as 4 study trials (4 weeks). It does not report the order in which conditions were administered, the interval between conditions, or whether a washout period was used. Those design details should not be inferred from the crossover label.
Randomized and double-masked are the registry’s design classifications. The record does not identify who was masked, how masking was maintained, or how the intervention order was randomized. It lists the study phase as NA and the status as completed. The study start is recorded as 2011-06 and primary completion as 2011-10. Oakland University is listed as the sponsor.
The registry describes secondary aims related to running performance and core temperature. It also names secondary outcomes for urine sodium concentration after the steady-state portion of the trial, blood sodium concentration and saliva sodium concentration. No participant-flow details, protocol deviations, adherence information or analysis population are 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: Participants received all three interventions in randomized fashion.
Overall Study
| Stage | 1/Placebo, V2R Agonist, V2R Antagonist |
|---|---|
| STARTED | 10 |
| COMPLETED | 10 |
| NOT COMPLETED | 0 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | 1/Placebo, V2R Agonist, V2R Antagonist |
|---|---|---|
| Participants analysed | 10 | |
| Age, Continuous | years | 35.5 (SD 13.1) |
| Sex: Female, Male: Female | Participants | 2 |
| Sex: Female, Male: Male | Participants | 8 |
| Region of Enrollment: United States | participants | 10 |
| years of running experience | years | 8.8 (SD 8.7) |
| BMI | kg/m2 | 22.5 (SD 3.3) |
| VO2 Peak | ml/kg/minute | 58.7 (SD 6.2) |
| Peak treadmill running speed | mph | 11.0 (SD 1.4) |
6. Primary Endpoint
The registry lists the primary outcome as Sweat Sodium Concentration Obtained After the Steady-state Portion of the Trial, measured over 4 study trials (4 weeks).
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mEq/L |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is sweat sodium concentration obtained after the steady-state portion of the trial, measured in mEq/L. The registry specifies a mean as the summary measure and standard deviation as the dispersion measure. Its timeframe is 4 study trials (4 weeks). The record’s description proposes that changes in sweat sodium concentration would parallel changes in urine sodium concentration across antagonist, agonist and placebo conditions if the stated primary hypothesis were true.
Sweat sodium concentration is used to assess whether V2R manipulation is associated with differences in sodium concentration in sweat during exercise. The endpoint therefore addresses a physiological response, rather than directly measuring running performance or a clinical event. In general, the mean describes the central level of a continuous measurement, while the standard deviation describes how spread out individual measurements are around that mean. Neither summary alone gives the uncertainty in a treatment comparison.
The registry record does not report a numerical mean, standard deviation, treatment contrast or confidence interval for this endpoint. It also does not state whether the analysis used a change score, a within-participant contrast or another approach. Accordingly, the endpoint and its rationale can be described, but the size, direction and precision of any comparison cannot be assessed from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the study question and design, but not the numerical result needed to answer the primary question. Although the study is marked completed and the primary endpoint is identified, no numerical values for sweat sodium concentration are reported. The record therefore does not show whether sweat sodium concentration differed among the V2R antagonist, V2R agonist and placebo conditions, or how large any such differences may have been.
The absence of a posted estimate also means precision cannot be judged. A confidence interval would ordinarily describe a range of values compatible with the data and the specified analysis, while reflecting sampling uncertainty. No confidence interval for the primary comparison is reported in the registry record. A p-value or other test result for that comparison is also not reported. Without these statistics, it is not possible to assess whether the data are consistent with a small difference, a larger difference, or no clear difference under a particular analysis.
The enrollment of 10 is relevant context for the scale of the study, but enrollment alone is not evidence about the observed effect or its precision. It does not reveal how many participants contributed usable primary-outcome measurements, whether all completed all intervention conditions, or whether missing observations affected the analysis. These details are not reported in the registry record. The crossover design may permit within-participant comparisons, but the record does not provide the analysis or the results needed to evaluate those comparisons.
The registered hypothesis links sweat sodium changes with urine sodium changes and proposes a role for V2R activity in sweat regulation. The record names urine sodium concentration after the steady-state portion as a secondary outcome, but supplies no numerical results for it or for the primary endpoint. Consequently, the proposed relationship cannot be assessed from the posted results. Nor can results for blood or saliva sodium, running performance or core temperature be interpreted from the information reported.
There are no analyses listed in the record, despite the listing of 10 outcome measures. This does not establish that no analyses were conducted; it means numerical analyses are not available in the registry record. Any claim about the direction, magnitude, statistical significance or practical importance of a treatment effect would go beyond what the posted results document. The defensible interpretation is limited to the registered question, the stated design and the absence of reportable numerical endpoint results.
9. Statistical Methods Explained
The registry identifies the primary endpoint as a continuous measurement summarized by a mean and standard deviation. General statistical explanation: a continuous outcome can take values across a measurement scale, rather than belonging only to a set of categories. The mean describes the average level in the analyzed observations. The standard deviation describes the variability among those observations. These are descriptive summaries; by themselves, they do not quantify the uncertainty in a comparison between intervention conditions.
For a treatment comparison, analysts commonly estimate a contrast between conditions and report an uncertainty measure such as a confidence interval. General statistical explanation: a confidence interval represents the range of effect values compatible with the observed data under the model and method used. Its width depends on factors such as the variability of the outcome, the amount of usable information and the analysis structure. A confidence interval is not reported for the primary endpoint in the registry record, and the record does not state the model or comparison estimator used.
The crossover designation matters to statistical interpretation. General statistical explanation: in a crossover study, each participant may contribute measurements under more than one condition. A within-participant analysis can account for the fact that measurements from the same person are related, and can focus on differences within people rather than treating all measurements as independent. Appropriate analysis may also need to account for treatment sequence, period effects or carryover, depending on the actual design and data. The registry record does not report the intervention sequence, washout arrangements, or statistical handling of period or carryover effects, so no particular crossover analysis should be assumed.
Randomization is intended to reduce systematic differences in how treatment conditions are assigned. Masking can reduce the influence of expectations or knowledge of condition on participant behavior, care or measurement. These are general purposes of the design features; the record does not explain how randomization was implemented or identify which parties were masked. The presence of the labels “randomized” and “double” therefore describes the registered design, but does not supply operational details or demonstrate how well those procedures were carried out.
The statistical planning assumptions state a two-sided significance level of 0.05, equal allocation between two arms and a normal approximation. They describe a planning illustration based on an effect that is a stated fraction of the observed effect. General statistical explanation: a significance level is a prespecified threshold used in a particular hypothesis-testing framework. A two-sided test considers departures in either direction. Equal allocation is an assumption about how information is distributed across the two groups in a planning calculation, while a normal approximation uses a normal distribution to approximate the behavior of an estimator or test statistic.
These planning assumptions do not establish the trial’s original design rationale or its actual analysis plan. The registry record does not report a sample-size justification, target power, or how any planning calculations were adapted to the crossover structure. Planning illustrations are not observed power and should not be read as an estimate of the probability that this completed study detected an effect. In particular, a calculation based on a fraction of an observed effect is a hypothetical planning exercise, not an additional result from the trial.
Dispersion is another consideration. General statistical explanation: over-dispersion occurs when variability is greater than assumed by a statistical model. If a model understates variability, standard errors can be too small and intervals too narrow. The primary endpoint is continuous and described with a mean and standard deviation; the registry does not report an over-dispersion assessment or a model for the endpoint. The relevant issue is not whether a particular adjustment was necessary, but that the analysis details are not reported and cannot be evaluated.
Because the primary results are not reported, no recalculated estimate can be checked against a sponsor analysis. There is no posted mean, dispersion estimate, contrast or uncertainty measure from which to perform an unadjusted recalculation. The registry record also does not report a sponsor analysis that could take precedence over a recalculated result. The statistical interpretation must therefore remain descriptive of the design and reporting status, rather than a numerical assessment of treatment effects.
10. Multiplicity, Missing Data and Analysis Populations
The record lists 10 outcome measures and identifies a primary endpoint alongside secondary outcomes for urine sodium concentration after the steady-state portion of the trial, blood sodium concentration and saliva sodium concentration. The study summary also describes secondary aims concerning running performance and core temperature. Having multiple outcomes can create multiple opportunities to identify apparently notable findings. General statistical explanation: multiplicity refers to the increased chance of at least one misleading positive result when many hypotheses are tested, particularly if no adjustment or prespecified hierarchy is used.
The registry record does not report a multiplicity strategy, an outcome hierarchy beyond identifying the primary endpoint, or a statistical analysis plan. It does not report numerical analyses for the listed outcomes. There is therefore no basis to determine whether multiplicity was addressed, which comparisons were formally tested, or whether any reported results were selected from a larger set of analyses.
The record reports no analysis entries. This is distinct from establishing that the study generated no data or that investigators performed no analyses; it means such analyses are not documented in the registry record. The handling of missing outcome measurements, withdrawals, protocol deviations and incomplete intervention periods is also not reported. The number enrolled does not establish how many participants contributed to each endpoint or comparison.
Analysis-population definitions are not reported in the registry record. It is therefore unclear whether a stated analysis, if available elsewhere, would include all randomized participants, only those completing all intervention conditions, or another population. No imputation method or sensitivity analysis for missing data is reported. These omissions prevent assessment of whether missingness or analysis choices could have influenced any estimated effect.
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 |
|---|---|---|---|
| 1/Placebo, V2R Agonist, V2R Antagonist | 0 | 10 | 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 |
|---|---|
| 1/Placebo, V2R Agonist, V2R Antagonist | 0 of 10 |
The safety entry groups the conditions under “1/Placebo, V2R Agonist, V2R Antagonist” and lists 10 participants at risk for serious adverse events and 0 affected. It also lists 10 at risk for other adverse events and 0 affected. These are the registry’s posted counts for the combined group label. The record does not give separate counts for placebo, agonist and antagonist conditions, so the figures should not be interpreted as condition-specific safety estimates.
The death entry is null. A null entry is not a count of zero; death information is not reported in the registry record. The record lists no top serious adverse-event terms, which means no terms are available in that field to characterize the events. The zero affected counts are registry entries, not proof that no event of any kind occurred or that every possible event was captured. The record does not describe the safety collection period, event definitions, severity categories or completeness of reporting.
These figures describe what is recorded, not a comparative safety analysis. With no condition-specific counts or numerical efficacy results, they cannot establish whether risk differs by intervention or support a broader conclusion about safety.
12. What the Result Does, and Does Not, Mean
The registry record documents a completed randomized, double-masked crossover study that examined V2R manipulation during exercise. It specifies an enrollment of 10, describes antagonist, agonist and placebo conditions, and identifies sweat sodium concentration after the steady-state portion of the trial as the primary endpoint. It also states a hypothesis about how sweat sodium might relate to urine sodium under the different conditions.
Those details define what the study set out to examine; they do not reveal what the measurements showed. Numerical primary results, effect estimates and confidence intervals are not reported in the registry record. As a result, the record cannot establish the direction or size of a difference in sweat sodium concentration, whether any comparison was statistically distinguishable from no difference, or how precisely an effect was estimated. It also cannot establish whether the registered hypothesis was supported.
The registry names secondary outcomes involving urine, blood and saliva sodium and describes secondary aims involving performance and core temperature. Their numerical results are not reported. Thus, no conclusions about these outcomes, or about relationships between them, can be drawn from the record. The serious and other adverse-event counts are recorded for a combined intervention-group label and do not provide condition-specific comparisons.
This absence of posted results should not be confused with evidence that the interventions had no effect. It is a limitation of what the registry record documents. Conversely, the registered hypothesis and biological rationale are not evidence that an effect occurred. A conclusion about the observed data would require numerical outcome results and enough methodological detail to understand the comparisons and analysis.
The appropriate reading is therefore narrow: the study’s question, endpoint, design classification and selected safety counts are documented, while the primary treatment-effect evidence is not. No medical or performance recommendation follows from these registry entries.
13. Why This Trial Matters Statistically
This study is statistically notable because its crossover structure raises questions about how repeated measurements within the same participant should be compared. General statistical explanation: repeated measurements from one person are usually related, so an analysis that treats them as unrelated observations can misrepresent uncertainty. A crossover comparison can use within-participant information, but the interpretation depends on the intervention sequence, timing, possible period effects and the model used. The registry record does not report those details.
The study also connects a primary physiological endpoint with several secondary measures. Sweat sodium concentration is the primary endpoint, while urine sodium concentration, blood sodium concentration and saliva sodium concentration are listed secondary outcomes. Running performance and core temperature are described as secondary aims. Considering several outcomes can make transparent reporting and a clearly specified analysis plan important, but the registry record does not report a multiplicity approach or numerical analyses.
Its main statistical lesson is about the distinction between a registered question and evidence that answers it. A completed status, a defined endpoint and a plausible hypothesis do not substitute for estimates and uncertainty. Without numerical primary results, readers cannot assess the magnitude, direction or precision of the effect. Enrollment of 10 describes study scale but does not, on its own, establish adequacy or inadequacy for a particular comparison.
The record also illustrates why safety counts need their structure preserved. Counts are attached to a combined group label rather than separate intervention conditions, and the death field is null. Those entries should not be transformed into comparative claims. Clear reporting of condition-specific results, analysis populations, missing data and the crossover analysis would be needed for a fuller statistical assessment.
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 that numerical results for the primary endpoint are not reported in the registry record. The record identifies sweat sodium concentration as the primary measure but does not give a mean, standard deviation, treatment contrast, confidence interval or test result. Therefore, the primary question cannot be answered from the posted results.
Several design details needed to interpret a crossover comparison are also absent. The registry does not report the intervention sequence, the interval between conditions, use of a washout period, handling of period effects or assessment of carryover. It identifies the study as randomized and double-masked, but does not describe the randomization procedure or state who was masked. These omissions limit assessment of both conduct and analysis without demonstrating that the design was flawed.
The record does not describe participant characteristics, participant flow, adherence, withdrawals, protocol deviations or the number with evaluable measurements for each endpoint. It does not identify an analysis population or explain how missing data were handled. The enrollment of 10 cannot answer those questions.
The outcome listing includes 10 measures, but no numerical analyses are listed. A multiplicity plan and a detailed statistical analysis plan are not reported. The record also does not report a sample-size justification. These gaps make it impossible to assess whether planned comparisons, missingness, or the number of outcomes influenced the interpretation.
Safety reporting is limited to counts under a combined intervention-group label, with no condition-specific counts. The death field is null, and no serious-event terms are listed. The registry does not describe the period or methods used to collect adverse events. These are limits on interpretation of the registry record, not proof that the study had particular unreported results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: V2 Receptor Effects on Fluid Regulation and Performance — NCT02084797.
- Registry record last updated 2016-05-12; status last verified 2016-04.
- Results first posted 2016-05-12.
- 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
NCT02084797 is a completed randomized, double-masked crossover study sponsored by Oakland University. The registry lists an enrollment of 10, a study start of 2011-06 and primary completion of 2011-10. The intervention conditions are described as V2R antagonist, V2R agonist and placebo; the arm description says all study participants received all interventions.
The primary endpoint is sweat sodium concentration after the steady-state portion of the trial, summarized as a mean with standard deviation and measured across 4 study trials (4 weeks). The stated hypothesis concerns changes in sweat sodium concentration under the different V2R conditions and their relationship to urine sodium concentration.
The record lists secondary sodium outcomes in urine, blood and saliva, and secondary aims involving running performance and core temperature. It does not report numerical primary or secondary outcome analyses. Safety counts list 0 affected for serious adverse events and 0 affected for other adverse events among 10 at risk in the combined group; death information is null. The design and endpoint are documented, but the treatment-effect results and key analysis details are not reported in the registry record.