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 Effects of Intranasal Oxytocin on Satiety Signaling in People With Schizophrenia (NCT01614093), a randomized phase 4 study. The primary outcome is Food Consumption After Intervention.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01614093 |
| Phase | Phase 4 |
| Condition | Schizophrenia |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | Quadruple |
| Enrollment | 24 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Maryland, Baltimore |
| Results posted | Yes |
2. Clinical Question
Population
People with schizophrenia. The registry lists an enrollment of 24. The safety entries report 16 participants at risk in each treatment group; the record does not explain how those entries relate to enrollment.
Intervention
A single intranasal dose of oxytocin, listed as 24IU.
Comparator
Intranasal saline placebo, also listed as 24IU. Participants were to receive oxytocin and placebo in random order.
Primary question
Does food consumption after the intervention differ between the oxytocin and placebo conditions, as an indicator of satiety signaling? The registry hypothesis is that greater satiety would be indicated by less consumption at the test meal 90 minutes after the preload.
The study was designed to compare treatment conditions within participants rather than to compare separate groups assigned to only one treatment. That structure can make each participant’s response under one condition informative about their response under the other. It also means that the interpretation depends on how the treatment sequence and repeated observations were handled in the analysis.
The registry describes a single-dose pilot paradigm. Its summary says that a signal of increased satiety might motivate follow-up studies concerning weight gain and overeating in people with schizophrenia. That is a statement of the rationale for the research, not evidence that the intervention changed food intake or that any downstream outcome was tested. Results for the primary endpoint are not reported in the registry record, so the clinical question cannot be answered from the posted results.
3. Trial Design
This is a Phase 4, randomized, quadruple-masked, crossover study sponsored by the University of Maryland, Baltimore. The registry lists schizophrenia as the condition and an enrollment of 24. The study began in 2012-06, had a primary completion date of 2014-01, and is marked completed.
The two interventions were intranasal oxytocin and intranasal saline placebo. Each participant was to receive oxytocin 24IU and saline 24IU in random order. The arm descriptions state that results would be reported by treatment and that the sample was too small for order effects. The registry does not describe the procedures used to generate or conceal the random sequence, or specify which roles were covered by quadruple masking.
In general, a crossover design compares treatment conditions within the same participant. This can account for stable differences between participants, but it also makes the sequence of treatments and the timing of measurements relevant. Potential period, sequence, or carryover effects depend on the trial procedures and analysis. The registry record does not report a statistical plan addressing those issues. The arm descriptions’ statement about the sample being too small for order effects is a limitation acknowledged in the record, not evidence that order effects were assessed or absent.
The design description gives the planned comparison and the primary endpoint, but the registry record does not report participant flow, treatment-period details, endpoint summaries, or an analysis of treatment differences. Consequently, completion status should not be read as confirmation that the stated hypothesis was supported. It indicates the study’s recorded status, while the outcome results needed to assess the comparison are not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: 17 participants were randomized, 16 participants participated in the trial. All data is available for only 16 participants
Overall Study
| Stage | Oxytocin/ Placebo |
|---|---|
| STARTED | 17 |
| COMPLETED | 16 |
| NOT COMPLETED | 1 |
Reasons for not completing this period:
| Reason | Oxytocin/ Placebo |
|---|---|
| Withdrawal by Subject | 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 | Oxytocin vs Placebo |
|---|---|---|
| Participants analysed | 16 | |
| Age, Continuous | years | 32 (18 to 64) |
| Sex: Female, Male: Female | Participants | 8 |
| Sex: Female, Male: Male | Participants | 8 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 7 |
| Race (NIH/OMB): White | Participants | 7 |
| Race (NIH/OMB): More than one race | Participants | 2 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | Participants | 16 |
6. Primary Endpoint
The registry lists the primary outcome as Food Consumption After Intervention, measured over 90 minutes.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | Grams |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is food consumption after intervention, measured in grams at 90 minutes. The registry describes the measure as a mean with standard deviation and identifies the test meal consumed after a preload. Its stated hypothesis is that greater satiety signaling would be reflected in less test-meal consumption.
Food consumed is a behavioral measure: it records intake rather than relying only on a participant’s report of fullness. The study summary also refers to behavioral and self-reported satiety signaling, but the registry identifies food consumption as the primary outcome. The endpoint is therefore intended to operationalize satiety through the amount eaten at the test meal. It does not directly measure later eating, long-term weight change, or prevention or treatment of weight gain.
For a continuous endpoint, a mean describes the average amount consumed, while a standard deviation describes variation among the measurements. In a crossover trial, the treatment comparison ideally reflects how intake differs for the same participants under the oxytocin and placebo conditions. The registry record does not report the means, standard deviations, participant-level paired differences, or an estimated treatment contrast. It also does not report endpoint results in grams. The direction and precision of any observed difference therefore cannot be evaluated from the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies a clear primary question: whether food consumption at the test meal differs after intranasal oxytocin compared with intranasal saline placebo. The design is randomized and crossover, with treatment order randomized and results intended to be reported by treatment. These details describe how the comparison was planned, but they do not establish what the comparison found.
No primary-endpoint values are reported in the registry record. There are no posted group means or standard deviations for food consumption, no treatment-effect estimate, and no confidence interval or p-value. The record lists zero analyses. Without those results, it is not possible to determine the direction or size of the observed difference, or how precisely it was estimated. The stated hypothesis that greater satiety would mean less food consumption remains a hypothesis in the registry description.
In general, an estimated treatment difference addresses the size and direction of a contrast, while a confidence interval describes the range of values compatible with the data under the analysis assumptions. A p-value, when reported, addresses compatibility with a specified null hypothesis; it does not measure the probability that the hypothesis is true or establish clinical importance. Those concepts cannot be applied to this trial’s endpoint without posted estimates and analysis results.
The registry summary frames the experiment as a single-dose pilot that could inform follow-up research if increased satiety were observed. The record does not report evidence of such an increase. Nor does it report longer-term outcomes related to overeating or weight gain. It would therefore be inappropriate to infer a sustained effect or a preventive or therapeutic effect from the trial description.
The safety entries are separate from the missing efficacy results. They report no serious adverse events and no deaths in either treatment group, with other adverse events recorded in both groups. Those descriptive counts do not substitute for the primary endpoint analysis, and the registry record does not provide enough detail to interpret event timing, severity, or attribution. Overall, the posted record documents the trial’s question and design, but not the results required to judge the treatment comparison.
9. Statistical Methods Explained
The record describes a randomized crossover comparison. Randomization assigns treatment order by chance; crossover means that participants receive both treatment conditions rather than remaining in only one. In general, comparing each participant with themself can reduce the influence of characteristics that remain stable across conditions. It does not remove the need to consider changes over time, treatment sequence, or possible carryover from an earlier condition.
Why can a crossover comparison be useful?
For a continuous outcome such as food consumption in grams, the key information in a crossover analysis is commonly the within-participant contrast between treatment conditions. In general, a paired analysis uses the relationship between a participant’s measurements, not just two separate treatment averages. This can improve precision when measurements from the same participant are related. Whether that approach was used in this study is not reported in the registry record. The record also does not provide the paired measurements or a treatment-effect estimate from which the analysis could be checked.
What does masking contribute?
The trial is labeled quadruple-masked. In general, masking can limit changes in behavior or assessment that arise when participants or study personnel know which treatment is being given. The registry does not identify the roles included in that label or describe how masking was maintained. The label alone does not establish that masking was successful, and no assessment of masking is reported in the registry record.
How should a mean and standard deviation be read?
The primary endpoint is specified as a mean with standard deviation. In general, the mean expresses the average measured food consumption, while the standard deviation describes how dispersed individual measurements are around that average. The standard deviation is not the same as the uncertainty around the estimated mean or treatment difference. A confidence interval is generally used to convey uncertainty in an estimate. The registry record does not report endpoint means, standard deviations, or confidence intervals, so none can be interpreted for this trial.
Why does over-dispersion matter?
Over-dispersion is a general concern when observed variability is greater than a statistical model assumes. If a model understates variability, standard errors can be too small and confidence intervals too narrow. The primary endpoint is described as a continuous measure, but the registry record does not report a model, diagnostic checks, or an over-dispersion assessment. There is no basis in the record to say that over-dispersion was present or that a particular adjustment was used.
What do the planning assumptions mean?
The registry describes a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. It says the effect to detect is a stated fraction of the observed effect, and that sample-size results are participants per arm for 80% power except for time-to-event calculations. These are planning assumptions, not a report of observed power. The record does not provide a trial-specific sample-size justification, and the planning description does not replace the missing endpoint analysis. No planning estimate can establish that the trial had adequate precision for its actual treatment effect.
In general, power is a design-stage probability of detecting a specified effect under stated assumptions. It is not a measure of whether the observed result is reliable after the study has been completed. Sample-size illustrations based on an observed effect are especially dependent on the estimate used and should be understood as planning scenarios. They do not supply a treatment estimate, confidence interval, or p-value for the trial.
The registry reports zero analyses and does not provide an analysis plan. The statistical method used for the primary endpoint, any adjustment for treatment sequence or period, and any handling of missing observations are not reported in the registry record. As a result, a reader cannot assess model assumptions, reproduce the analysis, or determine whether the analysis matched the crossover design.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies food consumption after intervention as the primary endpoint and lists one outcome measure. It does not report an analysis plan or a multiplicity procedure. Multiplicity generally arises when several outcomes, time points, or statistical comparisons are tested; without a prespecified analysis plan, it is not possible to determine which comparisons were intended to be confirmatory or whether any adjustment was planned. The registry record does not report additional efficacy analyses.
Missing-data handling is also not reported in the registry record. The record does not state how many participants contributed endpoint measurements, whether any measurements were missing, why data might have been missing, or how missing observations were treated. In a crossover study, missing measurements in one treatment condition can affect the within-participant comparison. Whether the analysis used complete pairs, another approach, or any sensitivity analysis is not reported.
The analysis population is not specified. The registry record does not say whether the primary analysis was based on all randomized participants, participants who received both conditions, or another defined group. It also does not describe exclusions after randomization or adherence to assigned treatment order. The enrollment entry and safety at-risk entries are not reconciled in the record.
These omissions limit assessment of the robustness and reproducibility of the primary comparison. They do not establish that missing data or multiplicity altered the result; the relevant methods and endpoint results are not reported in the registry record.
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 |
|---|---|---|---|
| Oxytocin | 0 | 16 | 0.0% |
| Placebo | 0 | 16 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Oxytocin | 0 of 16 |
| Placebo | 0 of 16 |
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 |
|---|---|
| Oxytocin | 2 of 16 |
| Placebo | 4 of 16 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Oxytocin | Placebo |
|---|---|---|---|
| Sedation | General disorders | 1 of 16 | 2 of 16 |
| Loss of Appetite | General disorders | 1 of 16 | 1 of 16 |
| Bruisng Easily | General disorders | 0 of 16 | 1 of 16 |
| Constipation | Gastrointestinal disorders | 0 of 16 | 1 of 16 |
| Dizziness | General disorders | 1 of 16 | 0 of 16 |
| Enuresis | General disorders | 0 of 16 | 1 of 16 |
| Malise | General disorders | 0 of 16 | 1 of 16 |
| Hyersalavation | General disorders | 0 of 16 | 1 of 16 |
| Stiffness | Musculoskeletal and connective tissue disorders | 0 of 16 | 1 of 16 |
The registry reports serious adverse events for the Oxytocin group and the Placebo group. In each group, 16 participants were listed as at risk, and 0 had a serious adverse event. Deaths were also recorded as 0 in each group. For other adverse events, 2 were recorded in the Oxytocin group and 4 in the Placebo group.
These are descriptive registry counts. The record does not report the event terms, timing, severity beyond the serious-versus-other categorization, or whether events were judged related to treatment. It also does not explain why the at-risk entries are 16 in each treatment group while the listed enrollment is 24. Because this is a crossover design, the registry entries should not be treated as evidence that the treatment groups represent separate sets of participants.
The absence of reported serious events in these entries does not establish that no adverse events occurred beyond those recorded, nor does the difference in other-event counts establish a treatment effect on safety. The registry record does not provide an inferential safety analysis or further event-level detail.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, quadruple-masked crossover study was completed to examine food consumption after intranasal oxytocin versus saline placebo in people with schizophrenia. It specifies a single-dose comparison, random treatment order, and a primary endpoint of test-meal consumption in grams 90 minutes after the preload. These details define the question and the intended outcome.
The record does not establish whether oxytocin changed food consumption. Endpoint summaries and treatment-effect analyses are not reported in the registry record. Without an estimate and its uncertainty, neither the direction of any observed contrast nor its precision can be assessed. The stated expectation of less consumption with greater satiety is not a result.
Even if a short-term change in meal consumption had been reported, it would address the measured behavior at the specified assessment, not by itself demonstrate longer-term changes in eating or weight. The registry summary discusses possible follow-up research on prevention or treatment of weight gain and overeating, but those outcomes are not reported as results of this trial.
Similarly, the safety counts are limited descriptive information. They do not establish comparative safety, explain the nature of other adverse events, or resolve how many participants contributed to each safety entry. The appropriate reading is therefore narrow: the registry describes a completed pilot comparison and reports limited adverse-event counts, but does not provide the primary outcome results needed to evaluate its satiety hypothesis.
13. Why This Trial Matters Statistically
This trial illustrates why design information and results need to be read separately. Randomization, masking, and a crossover structure describe safeguards and the intended comparison. They do not reveal the size, direction, or precision of an outcome difference. For those judgments, readers need endpoint estimates and an account of the analysis; neither is reported in the registry record.
The crossover design also makes the analysis method important. In general, within-participant comparisons can account for stable differences between participants, but the treatment sequence and period may matter. The registry’s arm descriptions explicitly say the sample was too small for order effects. Without an analysis plan or results, the impact of order cannot be evaluated, and no conclusion about its presence or absence is justified.
The record further distinguishes a biologically motivated hypothesis from an observed finding. Food consumption was selected as a behavioral indicator of satiety, and lower consumption was the hypothesized direction. A stated rationale helps explain why an endpoint was chosen; it does not establish that the endpoint changed. That distinction is essential when registry records contain design descriptions but no posted outcome analysis.
Finally, the planning assumptions are not equivalent to evidence about the completed study’s precision. Sample-size planning illustrations are conditional on assumptions and do not constitute observed power. Without the endpoint estimate and uncertainty, statistical interpretation remains limited, regardless of the trial’s completed status.
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 consequential limitation of the available record is that it does not report the primary endpoint results or any statistical analyses. Means, standard deviations, treatment contrasts, confidence intervals, p-values, and the analysis method are not reported in the registry record. The central research question therefore cannot be answered from the posted results.
The record gives limited detail about the crossover procedures. It states that participants received treatments in random order, but does not describe the sequence-generation or allocation-concealment methods, period structure, washout procedures, or analysis of period and sequence effects. The arm descriptions say the sample was too small for order effects, which limits what can be learned about those effects in this study.
Enrollment is listed as 24, while safety entries list 16 at risk in each treatment group. The record does not explain the relationship between these figures or report participant flow, endpoint availability, or reasons for any missing observations. The analysis population and missing-data approach are not reported in the registry record.
The registry describes the study as a single-dose pilot and focuses on food consumption at 90 minutes. The endpoint does not, by itself, provide evidence about sustained eating behavior or longer-term weight outcomes. The limited adverse-event information also lacks event-level detail and an inferential comparison. These limitations concern what can be established from the registry record; they do not show that an unreported problem occurred.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Effects of Intranasal Oxytocin on Satiety Signaling in People With Schizophrenia — NCT01614093.
- Registry record last updated 2019-08-28; status last verified 2019-08.
- Results first posted 2017-09-21.
- 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
NCT01614093 is a completed Phase 4 randomized, quadruple-masked crossover study sponsored by the University of Maryland, Baltimore. It enrolled 24 people with schizophrenia and compared intranasal oxytocin 24IU with intranasal saline placebo 24IU in random order. The listed primary endpoint was food consumption in grams at 90 minutes after the preload.
The registry record reports no primary endpoint results and lists zero analyses. It does not report the statistical method, analysis population, or missing-data handling. Safety entries list 0 serious adverse events and 0 deaths in each group, with other adverse events recorded as 2 for Oxytocin and 4 for Placebo. The record does not provide additional detail explaining those events or reconciling the safety entries with enrollment.