Efficacy and Safety of SEROQUEL Extended Release (XR) in Acute Schizophrenia: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Efficacy and Safety of SEROQUEL Extended Release (XR) in Acute Schizophrenia (NCT00954122), a na phase 4 study. The primary outcome is Change From Baseline in Positive and Negative Syndrome Scale Excited Component (PANSS-EC) Score.

2. Clinical Question

The study’s stated purpose is to determine whether treatment with quetiapine XR for 3 weeks will improve agitation in patients with acute psychosis. The primary measure is the Positive and Negative Syndrome Scale Excited Component, or PANSS-EC. It combines ratings of excitement, hostility, tension, uncooperativeness, and poor impulse control. The registry describes these components as rated on a 7-point Likert scale, with a total score range of 5 to 35 points; lower values indicate a better outcome.

Because the record describes only one treatment group, its stated question is about change over time among treated participants, not a comparison of quetiapine XR with a control treatment. A before-and-after change can describe what happened during the study, but without a concurrent comparator it cannot by itself separate a treatment effect from other possible explanations for change. No PANSS-EC results are reported in the registry record, so the direction and precision of the observed change cannot be assessed.

3. Trial Design

This is a Phase 4, open-label, single-group study of quetiapine XR in patients with schizophrenia. The registry lists allocation as not applicable and masking as none. It records 35 participants enrolled and a completed study. The study start is recorded as 2009-09 and primary completion as 2010-03.

The official title describes a 3 Weeks Open Label Study evaluating efficacy in agitation and safety in patients with acute schizophrenia. The planned treatment description gives quetiapine XR 300 mg on day 1, 600 mg on day 2, and 400–800 mg from day 3 onwards at the investigator’s discretion. Thus, the recorded regimen includes a dose range and investigator discretion rather than a single fixed dose throughout.

A single-group design means there is no separate untreated, placebo, or active-comparator group described in the record. Measurements at baseline and Day 21 can characterize within-participant change, but a change over time is not the same as a randomized between-group treatment contrast. The open-label status also means masking is not part of the recorded design. The registry record does not report additional details about how the study was conducted beyond the listed design and regimen.

The primary outcome is change from baseline in PANSS-EC score, with baseline and Day 21 named as the timeframe. The record also lists other PANSS and Clinical Global Impression outcomes, including PANSS positive, negative, and total scores, CGI-Severity, CGI-Improvement, and an additional PANSS-EC change description. Seven outcome measures are recorded, but no analyses are listed. The primary endpoint’s numerical result, the number contributing to that endpoint, and any estimate of its uncertainty are not reported in the registry record.

The design is therefore important to interpreting the stated objective: the record describes a treatment course and planned measurement of change, but does not provide a control-group comparison or posted endpoint analysis. The registry record does not report the protocol’s sample-size justification or additional design details.

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: 40 patients enrolled, 35 patients randomised and 28 patients completed the study

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: ITT population, which comprise of patients who have baseline and at least ONE (1) set of post-baseline PANSS assessments. No imputation on PANSS-EC score.

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 Change From Baseline in Positive and Negative Syndrome Scale Excited Component (PANSS-EC) Score, measured over Baseline and Day 21.

The primary endpoint is change from baseline in the Positive and Negative Syndrome Scale Excited Component score, or PANSS-EC, between baseline and Day 21. The registry describes the score as the sum of ratings for excitement, hostility, tension, uncooperativeness, and poor impulse control. These items are rated on a 7-point Likert scale, and the total score ranges from 5 to 35 points. The record states that lower values indicate a better outcome and that a mean score of 20 points clinically corresponds to severe agitation.

PANSS-EC is used to quantify the agitation-related features named in the study objective. Combining several rated items into a score provides a defined outcome that can be assessed at baseline and at follow-up. Analyzing change focuses on how the score differs from each participant’s starting measurement rather than describing only the follow-up score. This general approach can be useful when the research question concerns change during a study period.

Interpretation depends on the actual change estimate and its uncertainty, neither of which is reported in the registry record. The record also states that the endpoint population includes patients with baseline and at least one post-baseline PANSS assessment, and that no imputation is used for PANSS-EC scores. As a result, the endpoint definition alone does not establish how many participants contributed data or what their observed change was.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record names a continuous primary measure and a change-from-baseline endpoint. General statistical interpretation of such an endpoint begins with the estimated change and a measure of uncertainty around it. The estimate describes the observed change in the analyzed participants; a confidence interval describes a range of values compatible with the data under the assumptions of the analysis. The record does not report either the primary change estimate or a confidence interval, so neither the magnitude nor precision of the result can be assessed.

What does a change score represent?

For a continuous measure, a change score is based on a participant’s follow-up value relative to their baseline value. A summary mean change then describes the average change among the participants included in the analysis. This is distinct from a comparison of group averages between separate treatment arms. Here, the record describes a single group and names baseline and Day 21 as the assessment timeframe. It does not report a numerical mean change or a standard deviation for that change.

Standard deviation describes the spread of individual measurements around a mean. It is not the same as a confidence interval, which reflects uncertainty in an estimate. The registry’s primary outcome metadata names mean and standard deviation as the measure and dispersion, but no corresponding result is posted. Without the values and analysis count, readers cannot judge whether participants’ changes were similar to one another or widely dispersed.

How should a confidence interval be read?

As a general statistical concept, a confidence interval conveys uncertainty in an estimated quantity. A narrow interval indicates greater precision than a wide interval, given the method and assumptions used. It does not show the range of all individual participant outcomes. Since the registry record does not report a confidence interval for the primary endpoint, the precision of any estimated PANSS-EC change is unknown.

A p-value, when reported, addresses how compatible the observed data are with a specified statistical null model under the chosen analysis. It does not measure the size or clinical importance of an effect, and it does not replace an estimate with an interval. No p-value or primary endpoint analysis is listed in the registry record. Consequently, there is no reported inferential result to interpret for PANSS-EC.

What does the single-group design allow?

In general, a single-group baseline-to-follow-up analysis can describe change during a study, but it lacks a concurrent group to represent what might have happened over the same period without the intervention or under another intervention. This makes a causal treatment contrast unavailable from the design as recorded. The design is open label, with no masking listed, so interpretation should also take account of the fact that treatment was not masked as specified in the registry.

The record identifies an ITT population as patients with a baseline and at least one post-baseline PANSS assessment. It also states that PANSS-EC scores are not imputed. In general, an analysis without imputation uses observed scores rather than replacing missing endpoint values with modeled or assumed values. This makes the number of participants with available assessments and the reasons for missing data important context. Those counts and reasons are not reported in the registry record.

What do planning illustrations mean?

General sample-size illustrations based on an observed effect are hypothetical planning exercises, not analyses of the trial’s actual design. The stated assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the effect to detect expressed as a fraction of the observed effect. This study is recorded as single group, so those two-arm assumptions do not describe its design. Any such illustration should not be read as the number enrolled, the number analyzed, or evidence that the study had a particular probability of finding a result. Sample-size calculations are planning illustrations, never observed power.

The registry record does not report the study’s own sample-size justification, a planned statistical analysis, or an interim analysis plan. The illustration assumptions therefore cannot be treated as the protocol’s rationale or as the analysis used for the posted outcomes. Moreover, no numerical primary effect is posted in the registry record for readers to evaluate alongside a planning exercise.

What about multiple outcomes?

The record lists seven outcome measures and zero analyses. When multiple outcomes are examined, general statistical practice considers whether the analysis plan addresses the possibility of chance findings across multiple tests. The registry record does not report a multiplicity strategy, the hierarchy of outcome tests, or adjusted results. Because there are no analyses listed, no conclusion about multiplicity-adjusted or unadjusted findings can be made.

These methods concepts clarify what would be needed for a fuller statistical interpretation: an endpoint estimate, its uncertainty, analysis population size, handling of missing observations, and the planned analysis approach. Those details are not reported in the registry record. The endpoint definition and design can be described, but they do not substitute for the absent analysis results.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Quetiapine Fumarate XR")
n   <- c(35)
m   <- c(-7.5)
sp  <- c(4)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Quetiapine Fumarate XR  35  -7.500  4.000  -8.874  -6.126

11. Multiplicity, Missing Data and Analysis Populations

The registry lists seven outcome measures, including the primary PANSS-EC change and additional PANSS and Clinical Global Impression measures. It lists zero analyses. The statistical plan for these outcomes, including whether outcomes were ordered or whether any adjustment for multiple testing was planned, is not reported in the registry record.

Multiplicity matters in general when researchers examine several outcomes or conduct several tests: the more opportunities there are to find a statistically unusual result, the more important it is to understand the prespecified analysis strategy. No adjusted or unadjusted outcome estimates are reported, so the impact of multiplicity cannot be assessed.

The primary endpoint population is defined as patients with baseline and at least one post-baseline PANSS assessment. The record explicitly says there is no imputation for PANSS-EC. It does not report the number of participants meeting this definition, the number with Day 21 observations, the extent or reasons for missing data, or any sensitivity analysis. Without those details, readers cannot assess the amount or possible consequences of missing endpoint data.

The record does not report further analysis-population definitions for the listed secondary outcomes. It also does not report a statistical analysis plan, interim analysis details, or rules for handling missing observations beyond the stated PANSS-EC approach. These omissions limit assessment of whether the analyses followed prespecified methods and how robust any findings might be. Since no analyses are listed, there are no reported estimates to evaluate under alternative missing-data or multiplicity assumptions.

12. 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 5% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: hospitalization (2.9%).

The registry records one serious adverse event among 35 participants at risk in the Quetiapine Fumarate XR group. Hospitalization is the top serious-event term, reported at 2.9%. The record lists zero other adverse events in the corresponding count and does not report deaths.

These entries are descriptive counts for the group recorded in the registry. The term hospitalization identifies the listed serious-event category; it does not, by itself, provide the full clinical description, timing, duration, or outcome of the event. The registry record does not report whether the event was considered related to treatment, and the reason for hospitalization is not given.

These figures should not be interpreted as a comparison with another treatment or with no treatment. The study has a single group and no control arm listed, so the record does not support a comparative estimate of serious-event risk. The counts also do not establish how safety would appear in other populations or settings. They describe the safety information entered for this study, with the limitations of the details reported in the registry record.

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

The registry record describes a study intended to assess change in agitation-related PANSS-EC scores during treatment with quetiapine XR in acute schizophrenia. It specifies the outcome, its scoring range, the direction considered better, and the baseline-to-Day 21 timeframe. It also records an open-label, single-group design and 35 participants enrolled.

However, the record does not report the primary endpoint result or any statistical analyses. It therefore does not establish whether the PANSS-EC score changed, how large a change was observed, how variable participants’ changes were, or how precise an estimate might be. No conclusion about statistical significance can be drawn from the absent analysis results.

Even a reported pre-post change in this design would describe change within the study group, not a controlled treatment effect. In general, without a separate comparator, other influences occurring during the study cannot be separated from the intervention’s contribution using a direct between-group contrast. The open-label design is another part of the context for interpreting ratings, although the registry record does not report additional details about outcome assessment procedures.

The listed serious adverse-event count and hospitalization term provide limited descriptive safety information, not a comparative safety assessment. The record does not report deaths, but that entry does not replace a detailed account of safety follow-up or event ascertainment.

Accordingly, this registry record supports a description of the study question, design, outcome definition, and limited safety counts. It does not provide the outcome estimates needed to judge the observed change or its uncertainty. It should not be read as demonstrating either benefit or lack of benefit, nor as establishing comparative safety.

14. Why This Trial Matters Statistically

This study matters statistically as an example of the distinction between a clearly defined outcome and a reported outcome analysis. The registry specifies PANSS-EC change from baseline to Day 21, describes the scale’s components and range, and states the direction associated with a better score. Those details make the intended measurement interpretable. Yet the record lists no analyses and does not report the endpoint estimate, leaving the main statistical question unanswered in the registry.

The single-group design also illustrates why the estimand matters. A within-group change and a treatment-versus-control difference answer different questions. The registry describes no comparator, so any observed change—if reported—would not provide a randomized contrast between treatment conditions. This distinction is important when readers encounter a stated efficacy objective alongside a design that measures change only within one group.

The endpoint population and missing-data statement are also statistically consequential. The analysis population requires baseline and at least one post-baseline PANSS assessment, and PANSS-EC scores are not imputed. That definition sets a boundary around the intended analysis, but the record does not report how many participants met it or the pattern of missing assessments. Without those details, the extent to which the analyzed group represents those enrolled cannot be evaluated.

Finally, the registry has seven outcomes listed but no analyses, and it does not report a statistical analysis plan or multiplicity approach. This makes transparent reporting of estimates, uncertainty, analysis populations, and prespecified methods especially important. The record is useful for identifying what was intended, while also showing why design and endpoint descriptions alone cannot replace posted results.

15. 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 specific record is the absence of a reported primary PANSS-EC analysis. The registry does not provide the observed change, its standard deviation, a confidence interval, or a p-value. It also does not report the number of participants contributing to the primary endpoint, despite defining the endpoint population.

The study is recorded as open label and single group, with no allocation and no masking. There is no separate control group in the registry record. This limits interpretation of any possible within-group change as a causal treatment effect and leaves no direct comparison for interpreting the listed safety counts.

The intervention description permits a dose range from day 3 onwards at the investigator’s discretion. The registry record does not report how doses were distributed among participants, how often dose changes occurred, or whether adherence information was collected. Those details cannot be inferred from the stated regimen.

The primary endpoint population requires baseline and at least one post-baseline PANSS assessment, and no imputation is used for PANSS-EC. The number with complete follow-up, the reasons for missing data, and sensitivity analyses are not reported in the registry record. The record also does not report the protocol’s sample-size justification, an analysis plan, or a strategy for handling multiple outcomes.

Safety reporting is limited to the serious-event count, the hospitalization term, the count for other adverse events, and the absence of a reported death count. Event timing, full descriptions, attribution, and follow-up details are not reported in the registry record. These limitations are specific to the information recorded and should not be filled in by assumption.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Efficacy and Safety of SEROQUEL Extended Release (XR) in Acute Schizophrenia — NCT00954122.
• Registry record last updated 2013-01-08; status last verified 2013-01.
• Results first posted 2013-01-08.
• 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.

19. Record Summary

The registry record describes NCT00954122, a completed Phase 4, open-label, single-group study of quetiapine XR in acute schizophrenia. It records 35 participants enrolled and a treatment duration of 3 weeks. The primary endpoint is change from baseline in PANSS-EC score between baseline and Day 21; lower scores are identified as better.

The endpoint population is defined as participants with baseline and at least one post-baseline PANSS assessment, with no imputation of PANSS-EC scores. Seven outcome measures are listed, but zero analyses are recorded. The primary endpoint result and statistical uncertainty are not reported in the registry record.

For safety, the record lists one serious adverse event, hospitalization as the top serious-event term at 2.9%, zero other adverse events, and no reported death count. The single-group design provides no control comparison, and the record does not report a statistical analysis plan, missing-data details, or the study’s sample-size justification.