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 Best Event Schizophrenia Trial--A Randomized Double-Blind Trial of Aripiprazole and Risperidone in Schizophrenia (NCT00712270), a randomized phase 4 study. The primary outcome is Pre and Post Treatment PET and MRI Imaging.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00712270 |
| Phase | Phase 4 |
| Condition | Schizophrenia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 21 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Kettering Health Network |
| Results posted | Yes |
2. Clinical Question
Population
People with schizophrenia were eligible for a study focused on treatment response and neuroimaging, neuropsychological, and pharmacogenomic markers. The registry record lists enrollment of 21, but gives no detailed eligibility criteria or participant characteristics. Only 7 subjects completed the study, according to the primary outcome description.
Intervention
One study arm received aripiprazole for 16 weeks after screening and baseline procedures. Repeat baseline procedures were planned after treatment, followed by referral to community care. Details such as dose and permitted changes are not reported in the registry record.
Comparator
A second arm received risperidone for 16 weeks, with baseline procedures repeated afterward and referral to community care. The record also describes a Standard of Care arm involving screening and baseline procedures followed by referral to community care. The number assigned to each arm is not reported in the registry record.
Primary question
The listed primary outcome was pre- and post-treatment PET and MRI imaging, assessed at baseline and 16 weeks. The broader study aim was to investigate whether markers could help predict differential response to antipsychotic drugs. The record says data for the imaging objective are unavailable, so it does not provide an answer about imaging changes or differences between arms.
3. Trial Design
This was a phase 4, randomized, parallel-group study with quadruple masking. The registry lists aripiprazole and risperidone as drug interventions and describes a third Standard of Care arm consisting of screening and baseline procedures followed by referral to community care. The two drug arms were described as receiving 16 weeks of treatment before repeat procedures and referral to community care.
The registry lists enrollment of 21 and a terminated status. The primary outcome description says the study was terminated in 2009, that only 7 subjects completed it, and that randomization is not known. Thus, although the design record identifies the study as randomized, the available description does not establish which participants were randomized, how allocation was implemented, or how many participants were assigned to each arm. Those details are not reported in the registry record.
The study began in 2005-04, and its primary completion date is listed as 2008-12. The registry does not give a termination date in the information available. It identifies the sponsor as Kettering Health Network. No detailed description of the masking procedures, treatment doses, follow-up after the planned 16-week period, or reasons for termination is reported in the registry record.
The design sought to examine imaging alongside a broader interest in neuropsychological and pharmacogenomic markers of treatment response. The record lists one secondary outcome concerning pretreatment and posttreatment psychiatric rating scales, including PANSS and CGI. It does not provide the planned measurement schedule or analysis details for those scales. The number of listed outcome measures is 3, but no outcome analyses are recorded.
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 | Entire Study Population |
|---|---|
| STARTED | 21 |
| COMPLETED | 7 |
| NOT COMPLETED | 14 |
Reasons for not completing this period:
| Reason | Entire Study Population |
|---|---|
| Withdrawal by Subject | 11 |
| Screen Failure | 3 |
Analysis population for the primary outcome, as defined in the registry: Study was terminated back in 2009 with limited data available. Randomization is not known. Only 7 subjects completed study. Data for this objective is not available.
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.
Population: The study was pre-maturely terminated and limited data is available for reporting, since none of the study team members currently work in the organization, and are not able to be contacted. No baseline data are available.
| Characteristic | Unit | Standard of Care | Drug: Aripiprazole | Risperidone | Total |
|---|---|---|---|---|---|
| Participants analysed | 0 | 0 | 0 | 0 | |
| Age, Categorical: <=18 years | — | — | — | — | |
| Age, Categorical: Between 18 and 65 years | — | — | — | — | |
| Age, Categorical: >=65 years | — | — | — | — | |
| Sex: Female, Male: Female | — | — | — | — | |
| Sex: Female, Male: Male | — | — | — | — |
6. Primary Endpoint
The registry lists the primary outcome as Pre and Post Treatment PET and MRI Imaging, measured over At baseline and 16 weeks.
| 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 outcome is titled “Pre and Post Treatment PET and MRI Imaging,” with measurement at baseline and 16 weeks. PET and MRI are imaging approaches that can generate measures of brain structure or function. In general, collecting imaging before and after treatment can be used to describe within-person change over time, while comparing groups can assess whether observed changes differ by assigned intervention. The specific imaging measures and the exact contrast intended for this study are not reported in the registry record.
The study’s broader stated aim was to evaluate markers of differential treatment response. Imaging could therefore be considered alongside the study’s interest in neuropsychological and pharmacogenomic markers. However, the registry does not specify a particular marker, a threshold for response, or a statistical definition of differential response. The endpoint’s unit, summary measure, and dispersion are also not reported in the registry record.
Most importantly, the primary outcome description states that the study was terminated, that only 7 subjects completed it, and that data for this objective are unavailable. Consequently, there are no posted imaging estimates with which to describe change, precision, or differences between the drug arms or the community-care arm. The endpoint identifies what the study intended to assess, but it does not provide an observed imaging result.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized, quadruple-masked comparison involving aripiprazole, risperidone, and referral to community care. It lists 21 participants enrolled, while the primary outcome description reports that only 7 subjects completed the study. The number assigned to each arm and the allocation details are not reported in the registry record. The stated primary outcome is PET and MRI imaging at baseline and 16 weeks, but the record says data for that objective are unavailable.
As a result, there is no posted primary-outcome estimate, measure of uncertainty, or statistical test to interpret. The record contains no arm-level imaging results, no estimate of change over time, and no reported comparison among the study arms. It is therefore not possible to describe the direction or size of an imaging effect, or how precisely such an effect was estimated. The absence of a posted result is not evidence that the groups had the same outcome.
The registry lists 3 outcome measures and 0 analyses. A secondary outcome concerns pretreatment and posttreatment psychiatric rating scales, including PANSS and CGI, but no results for those measures are included in the record. The broader aims mention neuropsychological and pharmacogenomic markers, but specific results for those topics are not reported in the registry record. The available information therefore does not permit an assessment of whether any marker predicted or distinguished treatment response.
The safety record lists the entire study population as the group at risk. It records 0 serious adverse events, 14 other adverse events, and 0 deaths among 21 participants at risk. These are overall counts, not arm-specific comparisons. The record does not identify the event types, their timing, severity, or relationship to treatment. They should not be interpreted as evidence that one intervention was safer or less safe than another.
In general, a trial’s design can define a comparison that would be informative if outcome data were available. Interpretation still depends on observed outcomes, their uncertainty, the analysis population, and the extent of missing data. Here, the registry’s design information and overall safety counts do not replace the absent primary imaging results. No conclusion about comparative efficacy or treatment response can be drawn from the posted outcome information.
9. Statistical Methods Explained
The registry identifies this as a randomized, parallel-group study with quadruple masking. Those design labels describe the planned structure, but the record does not give enough detail to reconstruct the allocation process or the analysis. The primary outcome description specifically says randomization is not known. The available information also does not report which people were masked, how masking was maintained, or whether the treatment groups remained comparable after enrollment.
What would a baseline-to-follow-up comparison estimate?
In general, repeated measurements can be analyzed by describing change within each participant or by comparing follow-up outcomes between groups while accounting for baseline measurements. These approaches answer related but not identical questions. A within-group change does not by itself establish that the change was caused by the assigned intervention; a between-group contrast is usually needed to assess whether outcomes differed between assigned groups. The specific analysis intended for PET and MRI is not reported in the registry record.
The registry gives baseline and 16 weeks as the imaging timeframe, but does not name the imaging variables, define a primary summary measure, state a direction of benefit, or identify a model. It also provides no estimates, confidence intervals, or p-values for the imaging outcome. A confidence interval is, in general, a range of values compatible with the data and the assumptions of a statistical procedure; its width communicates precision. Without an estimate and interval, the precision of any treatment contrast cannot be assessed.
How should the stated group design be understood?
A parallel-group design assigns participants to groups that are followed over the same study period rather than switching each participant between interventions. Random allocation, when implemented as intended, can help balance measured and unmeasured characteristics across groups on average. This general benefit does not establish that allocation occurred as planned in this particular study. The record’s statement that randomization is not known, along with the lack of group-specific enrollment counts, prevents confirmation of the actual allocation pattern.
Masking is generally intended to reduce the influence of expectations or knowledge of assignment on care, measurement, and assessment. The registry’s quadruple-masking label does not identify the masked roles or the procedures used. Those details are not reported in the registry record. Accordingly, the label alone is not enough to judge how masking worked in practice or whether it was maintained.
What can the planning illustrations tell readers?
Planning illustrations use assumptions to show how a hypothetical study might be sized to detect an effect under a specified statistical framework. The stated assumptions for these illustrations are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They use the observed effect as a reference and consider stated proportions of that effect. These are planning assumptions, not a record of the trial’s original design justification, and they are not observed power.
The record does not report the trial’s own sample-size justification, an effect size used in its original planning, or the basis for selecting enrollment of 21. The primary imaging data are unavailable, so an observed imaging effect is not available to evaluate. Any planning illustration based on an observed effect should therefore be read only as a hypothetical calculation under its stated assumptions, not as evidence about the reliability of this trial’s findings or as a description of the original protocol.
What role would uncertainty and model choice play?
In general, statistical methods should match the outcome’s scale, distribution, and study design. Imaging outcomes may require choices about which regions or measures to analyze, how repeated observations are handled, and how missing scans are treated. The registry does not identify those choices. It also does not report whether any model was fitted, whether assumptions were checked, or whether adjusted and unadjusted results were planned.
Over-dispersion is a general issue in count data: observed variability can exceed what a simple model assumes, potentially making standard errors too small if the model is not suited to the data. It is not possible to determine whether over-dispersion is relevant to this trial’s primary imaging endpoint, and the record reports no model or diagnostic assessment. No model-specific inference can be reconstructed from the information available.
Because no outcome analyses are recorded, there is no sponsor analysis to compare with a recalculation from summary statistics. The record also contains no posted summary statistics for the primary outcome from which an independent recalculation could be made. Statistical interpretation must therefore remain descriptive: the design and intended endpoint are documented, but the primary outcome analysis is not available.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 3 outcome measures and 0 analyses. It names PET and MRI imaging as the primary outcome and lists a secondary outcome involving pretreatment and posttreatment psychiatric rating scales, including PANSS and CGI. The broader study aim also refers to neuropsychological and pharmacogenomic markers. The record does not give a complete list of planned hypotheses, outcomes, time points, or analysis contrasts.
When a study examines multiple outcomes or comparisons, the chance of at least one apparently notable finding can increase. In general, multiplicity procedures can help address that issue by controlling the interpretation of a set of tests. Whether such procedures were planned or used in this trial is not reported in the registry record. Since no analyses are recorded and no primary outcome data are available, there are no reported tests to evaluate for multiplicity.
The primary outcome description says only 7 subjects completed the study and that data for the imaging objective are unavailable. It does not explain the reasons for noncompletion, indicate which participants had usable imaging, or describe any missing-data method. The number included in an analysis, the handling of incomplete follow-up, and any assumptions about missingness are not reported in the registry record.
In general, an analysis population may include everyone randomized, everyone who began treatment, or only participants with measurements available, depending on the stated estimand and analysis plan. The registry does not define an analysis population for this study. With group allocation and outcome availability unclear, it is not possible to determine which participants contributed to any outcome analysis or how missing observations might affect interpretation.
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 |
|---|---|---|---|
| Entire Study Population | 0 | 21 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Entire Study Population | 0 of 21 |
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 |
|---|---|
| Entire Study Population | 14 of 21 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Entire Study Population |
|---|---|---|
| Dry mouth | General disorders | 8 of 21 |
| Daytime sleepiness | Nervous system disorders | 7 of 21 |
| Lightheadedness | Cardiac disorders | 7 of 21 |
| Insomnia | Nervous system disorders | 6 of 21 |
| Akinesia | Nervous system disorders | 4 of 21 |
| Constipation | Gastrointestinal disorders | 4 of 21 |
| Sialorrhea | General disorders | 3 of 21 |
| Headache | Nervous system disorders | 2 of 21 |
| Upper respiratory infection | Respiratory, thoracic and mediastinal disorders | 2 of 21 |
| Sinus congestion | Respiratory, thoracic and mediastinal disorders | 2 of 21 |
The registry lists the entire study population as the group at risk, with 21 participants at risk for both serious and other adverse events. It records 0 serious adverse events, 14 other adverse events, and 0 deaths. These are overall study counts; the record does not provide counts separately for aripiprazole, risperidone, or Standard of Care.
The categories should be kept distinct. The serious adverse event count is not the same as the count of all adverse events. The 14 other adverse events are not described by event type, number of people affected, severity, timing, or relationship to an intervention. The registry also does not state whether events could be counted more than once for a participant. These details are not reported in the registry record.
Because the safety information is pooled across the study population, it cannot establish whether event counts differed between groups. A count of 0 serious adverse events does not show that an intervention has no serious risks, particularly when the study was small and terminated. In general, safety comparisons require clearly defined event categories, group-specific denominators, and an account of how events were collected. The posted counts are descriptive and do not support a comparative safety conclusion.
12. What the Result Does, and Does Not, Mean
The registry documents a randomized, quadruple-masked, parallel-group study of aripiprazole, risperidone, and referral to community care for people with schizophrenia. It records enrollment of 21 and describes a primary imaging assessment at baseline and 16 weeks. The primary outcome narrative reports termination, only 7 subjects completing the study, and no available data for the imaging objective. Thus, the record establishes the intended comparison and endpoint, but does not provide a primary outcome result.
This distinction matters: an outcome that was planned is not an outcome that has been demonstrated. Without posted imaging estimates or arm-specific results, there is no basis for describing a treatment difference, a lack of difference, or the precision of either. The absence of results is not a finding of equivalence. The record also gives no reported results for the secondary psychiatric rating-scale outcome or for the broader marker aims.
The overall safety counts are limited to 0 serious adverse events, 14 other adverse events, and 0 deaths among 21 participants at risk. They do not identify treatment assignment or event details, so they cannot support a comparison of safety between interventions. They also should not be interpreted as establishing the absence of risk.
In general, a trial can be important for its question and design even when its registry record does not contain analyzable results. But a design description cannot substitute for outcome estimates, and incomplete follow-up can limit the information available. Here, participant allocation, outcome availability, missing-data handling, and the planned analysis are not sufficiently described to resolve those limitations. The posted information supports a description of the study and the limits of its reported data, not a conclusion about comparative treatment response.
13. Why This Trial Matters Statistically
This study is statistically notable because its stated scientific aim extended beyond comparing drugs: it sought to evaluate neuroimaging, neuropsychological, and pharmacogenomic markers of differential treatment response. Such a question requires more than a comparison of average outcomes. In general, assessing whether a marker distinguishes response requires a clearly defined marker, a response outcome, and an analysis that evaluates how the marker relates to differences between treatments. Those details and results are not reported in the registry record.
The record also illustrates the difference between a registered design and an interpretable result. It describes randomization and quadruple masking, but the primary outcome narrative says randomization is not known. It records enrollment of 21, while reporting only 7 subjects completed the study and that imaging data are unavailable. Without group-specific counts or an outcome analysis, the design labels cannot establish what comparisons were actually made or how precise they would be.
For clinical research, transparent reporting of participant flow, arm allocation, endpoint definitions, analysis populations, and uncertainty is important for judging how much a study can contribute. The registry record does not report those details for the primary outcome. It lists 0 analyses, so there are no posted estimates to interpret or independently check.
The safety record offers only pooled counts, which also underscores why denominators and group-level reporting matter. Overall counts can describe what was recorded across the study, but cannot answer whether event patterns differed by intervention. The trial therefore highlights a general statistical principle: a clinically relevant research question and a structured design do not, by themselves, provide evidence about an outcome. The results and their uncertainty are essential to that 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.
Several limitations are specific to the information recorded for this trial. The study is marked terminated, and its primary outcome description says only 7 subjects completed it. The reason for termination, the timing of participant withdrawals, and the reasons for noncompletion are not reported in the registry record. The record lists enrollment of 21 but does not show how many participants were assigned to each arm or how many contributed usable data to any outcome.
Although the design is identified as randomized, the primary outcome description says randomization is not known. The allocation sequence, concealment procedures, and actual group assignments are not reported in the registry record. The record also labels masking as quadruple but does not identify the masked roles or describe how masking was maintained.
The primary outcome is broadly described as PET and MRI imaging at baseline and 16 weeks. Specific imaging measures, units, summary statistics, and analysis contrasts are not reported. The description states that data for the objective are unavailable. No results are posted for the secondary psychiatric rating-scale outcome, and the record lists 0 analyses.
Missing-data methods, analysis populations, multiplicity procedures, protocol deviations, treatment doses, and detailed eligibility criteria are not reported in the registry record. The safety counts are pooled across the study population and lack event descriptions and arm-level breakdowns. These limitations prevent an assessment of comparative outcome estimates, their precision, and whether the observed safety events differed by intervention.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Best Event Schizophrenia Trial--A Randomized Double-Blind Trial of Aripiprazole and Risperidone in Schizophrenia — NCT00712270.
- Registry record last updated 2020-07-28; status last verified 2018-11.
- Results first posted 2018-12-14.
- 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
This phase 4 study was a randomized, quadruple-masked, parallel-group trial in schizophrenia, sponsored by Kettering Health Network. It compared 16 weeks of aripiprazole or risperidone with a Standard of Care arm involving screening, baseline procedures, and referral to community care. The registry lists enrollment of 21, a start date of 2005-04, primary completion in 2008-12, and terminated status.
The primary outcome was pre- and post-treatment PET and MRI imaging at baseline and 16 weeks. The record says the study was terminated, only 7 subjects completed it, randomization is not known, and data for the imaging objective are unavailable. It lists a secondary psychiatric rating-scale outcome including PANSS and CGI, 3 outcome measures, and 0 analyses.
For the entire study population, the safety record lists 0 serious adverse events, 14 other adverse events, and 0 deaths among 21 participants at risk. These counts are not separated by intervention. The registry record does not provide outcome estimates or analyses that support a comparative conclusion.