Oxytocin and CBSST for People With Schizophrenia: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Oxytocin and CBSST for People With Schizophrenia (NCT01752712), a randomized na study. The primary outcome is Birchwood Social Function Scale (BSFS) Total Score.

2. Clinical Question

The question concerns the additional contribution of oxytocin when both groups receive CBSST, rather than a comparison of CBSST with no psychosocial intervention. The registry description frames social function as an important area of impairment and describes CBSST as an approach intended to address beliefs and skills associated with social engagement. It presents oxytocin as a possible adjunct, with proposed social-affiliation mechanisms described as hypotheses rather than established trial findings.

The primary outcome was scheduled across treatment weeks 0, 12, and 24, plus follow-up week 36. Those repeated assessments describe the intended measurement schedule; they do not establish that every participant contributed a score at every time point. The record defines the primary analysis population separately at each time point as participants with a completed BSFS assessment. No treatment-effect estimates, uncertainty intervals, or primary-outcome test results are reported in the registry record, so the comparative question remains unanswered by the posted numerical results.

3. Trial Design

The registry describes a randomized, triple-masked, parallel-group trial, recorded as completed. Enrollment is listed as 83. The sponsor is the University of Maryland, Baltimore. The recorded phase is NA. The study start is listed as 2014-01 and primary completion as 2016-08.

The two intervention groups received CBSST alongside nasal spray. One group received oxytocin and the other placebo. The oxytocin description specifies 80 IU/day intranasally, divided into morning and evening doses of 40 IU. The placebo spray was described as matched in appearance and similarly administered in morning and evening doses. Both groups therefore shared the CBSST component; the comparison addresses the addition of oxytocin versus placebo within that treatment context.

Randomization indicates that assignment was intended to be determined by chance, while parallel-group design means participants were assigned to one group rather than crossing between treatments. The registry labels masking as triple but does not identify which roles were masked or explain how masking was maintained. Further details of sequence generation, allocation concealment, treatment adherence, or the statistical plan are not reported in the registry record.

The primary outcome was the Birchwood Social Function Scale total score. Assessments were scheduled at treatment weeks 0, 12, and 24, and follow-up week 36. The record also lists five secondary outcomes: total scores on the Defeatist Performance Attitudes Scale, Asocial Belief Scale, Schedule for Assessment of Negative Symptoms, and Brief Psychiatric Rating Scale, plus the Brief Psychiatric Rating Scale Psychosis Score. It lists six outcome measures overall, but no numerical analysis results are reported for these outcomes.

Enrollment is a registry-level study figure and should not be treated as the number analyzed at every time point. For the primary outcome, the stated analysis population required a completed assessment at the relevant time point. The record does not give the number contributing data at each assessment or explain losses to follow-up.

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: 83 participants signed a consent form for the study. 4 of these subjects were deemed ineligible before starting any study procedures, and 17 participants were withdrawn from the study prior to randomization for various reasons. Therefore, 62 subjects were randomized to a study treatment group (31 CBSST+oxytocin, 31 CBSST+placebo).

Overall Study

Analysis population for the primary outcome, as defined in the registry: Only participants who were enrolled in the study and had completed a BSFS assessment were analyzed at each study time point.

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.

6. Primary Endpoint

The registry lists the primary outcome as Birchwood Social Function Scale (BSFS) Total Score, measured over Treatment weeks 0, 12, and 24, plus follow-up week 36.

The primary endpoint is the total score on the Birchwood Social Function Scale (BSFS), a continuous measure reported in units on a scale. Its purpose in this study is to assess social function, the outcome targeted by the comparison of CBSST plus oxytocin with CBSST plus placebo. The registry describes the score as the sum of seven sections covering social engagement withdrawal, interpersonal communication and relationships, prosocial activities, recreation, independence in performance, independence in competence, and occupation or employment.

The possible section scores differ in range. The record states that the total can reach 247 and that the minimum depends on employment status: it is 0 for participants who are unemployed and 7 for those with employment. The registry explicitly says that a lower total score indicates a lower social function rating. This direction is important when interpreting a reported score or change; it would not be appropriate to assign a clinical interpretation to a numerical difference without the relevant results and context.

Assessments were scheduled for treatment weeks 0, 12, and 24, plus follow-up week 36. Repeated measurement allows the outcome to be assessed over treatment and at follow-up, but the registry record does not report the results at those times. It also does not specify a single primary time-point contrast or an analysis combining measurements over time. The outcome description says that only enrolled participants with a completed BSFS assessment were analyzed at each time point.

Social function is used because the registry frames social engagement and related functioning as important difficulties in schizophrenia and schizoaffective disorder. The endpoint is a rating scale outcome, not a direct count of social interactions or a measure of a single symptom.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods are only partly described in the registry record. It identifies randomization, triple masking, a parallel-group design, a continuous primary outcome, and a time schedule for measurement. It does not report the primary analysis model, treatment contrast, handling of repeated assessments, covariate adjustment, missing-data procedure, or test statistic. Those details are not reported in the registry record and should not be inferred from the design labels alone.

What does a continuous outcome mean?

General explanation: a continuous outcome can take a range of numerical values rather than representing only a category or event. A mean summarizes the average value in a group, while a standard deviation describes how spread out individual measurements are around that average. The registry describes the BSFS total as a mean-type continuous measure and names standard deviation as its dispersion measure. It does not publish the group means or standard deviations for the primary outcome.

For a comparison between randomized groups, an effect estimate would ordinarily express the contrast in the outcome between groups, potentially at a specified assessment or across assessments. A confidence interval would describe the range of effect values compatible with the data and the analysis assumptions. It conveys precision, not the probability that a particular treatment effect is true. These are general statistical explanations; no treatment-effect estimate or confidence interval for the BSFS is reported in the registry record.

How should the repeated assessment schedule be understood?

General explanation: repeated measurements on the same participants are related rather than independent. An analysis that uses measurements across time should account for that relationship; otherwise, uncertainty may be represented incorrectly. A longitudinal model can estimate change over time and differences between groups over time, but the particular model and contrast must be specified. The registry lists treatment weeks 0, 12, and 24 and follow-up week 36, but does not report a longitudinal model, a selected time-point contrast, or an overall treatment-by-time test.

The presence of measurements at several times also raises questions about which comparison is primary. A result at one assessment is not interchangeable with a result that summarizes the full trajectory. The record does not explain whether the intended emphasis was a particular week, change from baseline, or a pattern across all assessments. The registry skip information says that the primary outcome has several categories or time points and was not reduced to one comparison. Consequently, no single primary numerical comparison should be reconstructed from the schedule.

Why do uncertainty and variation matter?

General explanation: an observed difference is an estimate, and its precision depends in part on the amount and variability of the data. A narrow confidence interval indicates greater precision than a wide interval, although interpretation also depends on the scale and relevance of the effect. A p-value, if reported, addresses compatibility of the data with a specified null hypothesis under the analysis assumptions; it does not quantify the size or clinical importance of an effect. Neither p-values nor confidence intervals for the primary outcome are reported in this registry record.

Standard deviations are useful for understanding the variation of individual scores, but they are not themselves uncertainty intervals for a group difference. To assess the comparison, readers would need the group summaries, analysis population, effect estimate, and its uncertainty. These primary-outcome statistics are not reported in the registry record.

What do the planning assumptions mean?

The record describes a sample-size planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. It says that the effect to detect is expressed as a stated fraction of the observed effect. Such a calculation is a planning illustration, not observed power and not evidence that the trial had a particular probability of detecting an effect. The actual sample-size illustration values and the observed effect are not included in the registry record for this analysis.

General explanation: a planning calculation estimates how much information a future design may require under its assumptions. It is sensitive to the assumed effect, outcome variability, allocation, significance criterion, and analysis method. A planning value based on an observed effect can be especially dependent on that estimate. It should not be interpreted as a retrospective measure of whether the completed study succeeded, and it does not replace the observed treatment-effect estimate with its confidence interval.

The planning assumptions do not establish the trial's original design rationale. The registry record does not report the protocol's sample-size justification, whether there were interim analyses, or the complete statistical analysis plan. Those details should not be inferred from a planning illustration.

What does over-dispersion mean in general?

General explanation: over-dispersion occurs when observed variability exceeds what a statistical model assumes. It can make standard errors too small if the model does not account for the extra variability, leading to misleadingly precise inference. The BSFS is described as a continuous score with standard deviation, and the registry record does not identify an over-dispersion issue or a model that would require this adjustment. This concept therefore provides general context, not a claim about the trial's data.

Because no numerical outcome analyses are reported, recalculated comparisons from posted summary statistics are not available. There is no basis in the registry record for independently checking an effect estimate or its uncertainty. The sponsor's own analysis cannot be compared with a recalculation from absent summaries.

10. Multiplicity, Missing Data and Analysis Populations

The primary outcome is measured at several scheduled time points, and the registry lists multiple secondary outcomes. This creates potential multiplicity: testing or emphasizing several outcomes or time points can increase the chance of a seemingly notable result arising by chance. General explanation: statistical plans commonly address multiplicity by defining a primary contrast in advance, adjusting inference, or treating additional comparisons as exploratory. The registry record does not report a multiplicity procedure, a hierarchy of outcomes, or which assessment time point would serve as the primary contrast.

The registry's skip information notes that the primary outcome has several categories or time points and was not reduced to one comparison. No numerical primary comparison is therefore presented in the information available for this analysis. The record does not state whether analyses were performed for each time point, combined across time, or adjusted for multiple comparisons. The number of analyses is listed as 0, but the meaning of that registry entry is not explained; it should not be used to invent an analysis plan or to conclude that no analyses took place.

For missing data, the record says that only participants enrolled in the study and completing a BSFS assessment were analyzed at each time point. This describes an assessment-specific analysis population, but does not explain how missing scores were handled, whether any imputation was used, or whether analyses included all randomized participants. The number assessed at each time point and reasons for missing assessments are not reported in the registry record.

Consequently, the degree to which missingness or multiplicity could affect the primary inference cannot be evaluated from the registry record. These gaps are relevant when reading any eventual results, but do not by themselves establish the direction or size of bias.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: hospitalization (3.2%).

The registry reports serious adverse events separately by treatment group. For CBSST plus oxytocin, 31 participants were listed as at risk and 1 as affected by a serious adverse event. For CBSST plus placebo, 31 were listed as at risk and 0 as affected. The registry also lists 3 and 5 participants, respectively, as affected by other adverse events, with 31 at risk in each group.

These are registry counts, not a complete account of event timing, duration, severity beyond the serious-event classification, or relationship to treatment. The record does not report whether an individual could experience more than one event, nor does it provide event-level descriptions for all adverse events. The death entries are null, so deaths are not reported in the registry record; a null entry should not be interpreted as evidence that no deaths occurred.

Hospitalization is listed as the top serious adverse event term at 3.2%. The registry entry does not specify an arm-specific value for that term in the registry record. The percentage should therefore be read as the posted term-level figure, not as a treatment-group rate or a basis for comparing groups. The adverse-event counts should not be treated as evidence of a treatment effect or used to draw conclusions about safety beyond what the registry record reports.

12. What the Result Does, and Does Not, Mean

The trial addresses a specific comparative question: whether adding oxytocin to CBSST is associated with a different BSFS social-function score than adding placebo to CBSST. It does not compare CBSST with no training, and it does not isolate the effect of CBSST itself. Both groups are described as receiving CBSST, while the nasal spray differs.

The registry record is useful for identifying the study population, randomized parallel-group design, intervention descriptions, primary outcome, assessment schedule, and selected adverse-event counts. It also makes clear that the primary outcome was intended to be assessed at treatment weeks 0, 12, and 24, plus follow-up week 36. These design details explain what the study set out to examine, but they are not results.

The record does not report numerical BSFS results, treatment-effect estimates, confidence intervals, or primary-outcome tests. It therefore does not show whether scores differed between groups, how large any difference was, or how precisely it was estimated. The absence of posted numerical results is not evidence of no difference, equivalence, or lack of effect. Those conclusions require results and an analysis designed to support them.

The outcome is a rating scale for social function, with lower total scores indicating a lower social function rating. Without the actual score distributions and comparative analysis, neither the direction nor the practical importance of an effect can be determined. The registry also does not provide a threshold for a clinically important difference or explain how change over multiple time points was to be summarized.

Likewise, the adverse-event entries provide counts and a serious-event term, not a complete benefit-risk assessment. The entries do not resolve event attribution, missing safety information, or the relationship between the overall enrollment figure and the listed at-risk denominators. The findings should be interpreted only within the study's described population and intervention context. No conclusion about clinical care follows from the registry information alone.

13. Why This Trial Matters Statistically

This trial is statistically informative as an example of why a clearly stated clinical question and a numerical result are separate parts of evidence. The registry specifies a randomized comparison, a common CBSST component, an oxytocin-versus-placebo contrast, and a social-function endpoint. These features clarify the intended estimand in broad terms: the comparative association of the added nasal spray within the CBSST setting.

At the same time, a repeated outcome schedule creates analytic choices. A comparison at one treatment week can answer a different question from a comparison across the full pattern of scores through follow-up. The registry lists several assessment times but does not report the selected contrast or model. Statistical interpretation depends on those decisions, as well as on the participants contributing data at each time point.

The record also illustrates the importance of reporting effect estimates and uncertainty rather than only design information. Group means, variability, a treatment contrast, and a confidence interval would help readers judge the size and precision of the primary comparison. Without those results, enrollment and masking labels cannot establish what the observed data show.

Multiplicity and missingness matter in a study with repeated assessments and several listed secondary outcomes. A prespecified analysis plan can clarify which comparisons carry primary inferential weight and how incomplete outcome data are handled. Those details are not reported in the registry record. Their absence prevents a full appraisal of the intended inferential framework, but does not justify assuming that a particular method was or was not used.

The statistical value of this registry record is therefore primarily in describing the planned comparison and its limitations as a source of outcome evidence. It identifies what was measured and when, while leaving the magnitude and precision of the primary result unreported.

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 principal limitation for interpreting this trial from the registry record is the absence of numerical results for the primary BSFS outcome. Group summaries, treatment effects, confidence intervals, and test results are not reported. The record also does not provide numerical results for the secondary outcomes listed. Thus, the comparative social-function finding cannot be assessed from the information available.

The primary outcome has repeated scheduled assessments, but the record does not identify a single primary time-point contrast or specify whether a longitudinal model was used. It does not describe multiplicity control despite the several outcome measures and assessment times. These omissions make it difficult to understand how inferential emphasis was intended to be assigned.

The analysis population is defined as participants enrolled and completing a BSFS assessment at each time point. The record does not provide the number with completed scores at each assessment, reasons for missingness, or a method for handling missing data. It also does not state whether the primary analysis followed an intention-to-treat principle or another approach. These details are not reported in the registry record.

Although masking is recorded as triple, the masked roles and procedures are not described. The allocation-generation and concealment methods are also not reported. The registry does not provide information on adherence or treatment exposure beyond the arm descriptions. These are limits on appraisal of implementation, not evidence that the procedures were inadequate.

For safety, the record gives adverse-event counts, but does not provide event-level detail, attribution, timing, or an explanation of the null death entries. The at-risk denominators are reported as 31 for each group, while overall enrollment is 83; the record does not explain the relationship between those figures. They should not be reconciled by assumption.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Oxytocin and CBSST for People With Schizophrenia — NCT01752712.
• Registry record last updated 2019-09-25; status last verified 2017-11.
• Results first posted 2017-10-31.
• 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.

18. Record Summary

NCT01752712 is a completed randomized, triple-masked, parallel-group study sponsored by the University of Maryland, Baltimore. The registry lists enrollment of 83 and records the phase as NA. It compares CBSST plus intranasal oxytocin with CBSST plus placebo in people with schizophrenia or schizoaffective disorder.

The primary endpoint is the BSFS total score, scheduled for assessment at treatment weeks 0, 12, and 24, plus follow-up week 36. The registry defines the score as a measure of social function, with lower scores indicating a lower social function rating. Five secondary outcomes are listed alongside the primary outcome.

The registry reports adverse-event counts, but does not report numerical primary-outcome analyses, effect estimates, or uncertainty intervals. Details of the statistical analysis plan, multiplicity handling, and missing-data methods are not reported in the registry record. The posted information describes the study question and design but does not establish the comparative primary-outcome result.