An Efficacy, Safety And Tolerability Study of Flexibly Dosed Paliperidone Extended-Release (ER) in Participants With Schizophrenia: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for An Efficacy, Safety And Tolerability Study of Flexibly Dosed Paliperidone Extended-Release (ER) in Participants With Schizophrenia (NCT00757705), a na phase 4 study. The primary outcome is Change From Baseline in Positive and Negative Syndrome Scale (PANSS) Total Score at Week 24.

2. Clinical Question

The study focus was maintained efficacy, tolerability, and safety after transition to paliperidone ER among participants whose prior treatment with other oral atypical antipsychotic medication had been unsuccessful. Because there is only one treatment group, any change over time is a within-group observation. It cannot by itself distinguish a treatment-associated change from other influences, such as the course of symptoms, expectations in an open-label study, or changes in care during follow-up. Those considerations do not negate the descriptive value of the study, but they define what the design can address.

3. Trial Design

This was a Phase 4, open-label, prospective, single-group study sponsored by Johnson & Johnson Taiwan Ltd. The registry lists 299 participants enrolled and the study status as completed. The recorded study dates are 2008-03 for start and 2009-05 for primary completion. The intervention was paliperidone extended-release (ER), described as flexibly dosed. No allocation was applicable, and the record lists no masking.

The official title describes a transition to paliperidone ER in participants with schizophrenia who had previously been unsuccessfully treated with other oral antipsychotics. The brief summary further describes the prior medication as other oral atypical antipsychotic medication. The record therefore concerns a selected group with a history of unsuccessful treatment, rather than an unselected population with schizophrenia. Details about the specific prior drugs, the criteria for unsuccessful treatment, and the number of participants transitioning from each drug are not reported in the registry record.

With a single group and no masking, outcomes were assessed while participants and study personnel knew that paliperidone ER was being given. A prospective design can define the order in which treatment and follow-up assessments occur, but it does not create a concurrent control group. Accordingly, comparisons between baseline and later measurements describe change within the enrolled group; they do not have the same interpretation as a randomized comparison between treatments.

The primary time point was Week 24, with the primary outcome defined as change from baseline in PANSS total score. Secondary outcomes included PANSS Marder subscales, the proportion meeting a PANSS improvement threshold, functioning measures, clinical global impression, health-related quality of life, treatment satisfaction, and sleep-related scores. Numerical results for these outcomes are not reported in the registry record. Dose details, follow-up procedures beyond the listed outcome timeframes, and the study's protocol-specific statistical plan 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.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Intent-to-treat (ITT) population included all participants who received at least 1 dose of study drug and had at least one post-baseline assessment. Missing data was imputed using last observation carried forward (LOCF). Here, 'n' signifies those participants who were evaluable for this outcome measure at specified 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 Change From Baseline in Positive and Negative Syndrome Scale (PANSS) Total Score at Week 24, measured over Baseline, Week 24.

The primary endpoint was change from baseline in PANSS total score at Week 24. PANSS is a 30-item measure of neuropsychiatric symptoms associated with schizophrenia. Each item is scored from 1 (absent) to 7 (extreme), and the total score ranges from 30 to 210. Higher total scores indicate greater symptom severity. The scale also reports positive, negative, and general psychopathology subscales.

A change score expresses how a participant's score at follow-up differs from the baseline score. In general, repeated measurement of symptom severity can describe whether scores shifted over the follow-up period and how variable those shifts were. Because higher PANSS scores indicate greater severity, a lower follow-up score relative to baseline would correspond to a direction of change toward fewer or less severe symptoms on this scale. That describes the scale's direction, not a finding from this study: the registry record does not report the primary change estimate or its standard deviation.

PANSS is used to quantify symptom severity in a structured way, rather than relying only on an unstructured impression. A total score combines information across the instrument's items, while subscales retain information about symptom domains. A total score can be useful for an overall summary, but it does not show which individual symptoms changed, whether every participant changed in the same direction, or how participants experienced the change. Those interpretations require results and supporting information not reported in the registry record.

The outcome was assessed from baseline to Week 24. The record describes an intent-to-treat population that included participants who received at least 1 dose and had at least one post-baseline assessment, with missing data imputed using last observation carried forward. The number evaluable for this endpoint and the numerical result are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The record gives enough information to explain the endpoint and some aspects of the analysis population, but it does not report the numerical primary result or a complete statistical analysis plan. The general explanations below describe how these methods are usually interpreted; they do not imply additional methods were used in this study.

What does a mean change represent?

The primary outcome is continuous: it is a numerical score that can take a range of values. The registry identifies the summary measure as a mean and the dispersion measure as a standard deviation. In general, a mean change summarizes the average within-participant difference between follow-up and baseline. The standard deviation describes how spread out individual changes are around that average. A mean alone does not show whether changes were similar across participants or whether a smaller group had especially large changes in either direction.

The registry record does not report the mean change or its standard deviation. It therefore does not allow readers to judge either the average change or the spread of participant-level changes. It also does not report a confidence interval for the primary endpoint. In general, a confidence interval gives a range of values compatible with the data and analysis under the method's assumptions. Its width conveys precision: a narrower interval indicates greater precision than a wider one. Without an interval or the underlying result, precision cannot be assessed.

How should a single-group baseline comparison be read?

In a single-group study, baseline and follow-up scores are measurements from participants receiving the study intervention, not outcomes from separate treatment and control groups. A change over time can describe what happened in the observed group. It cannot, on its own, estimate the difference that would have occurred under an alternative treatment or no study treatment. General influences such as natural symptom fluctuation, concurrent care, and expectations may also affect follow-up measurements. A control group can help address some of these questions, but this study is not recorded as having one.

The open-label designation means that masking was absent. As a general methodological point, awareness of treatment can affect subjective reporting or assessment. PANSS uses a structured scale, but structured measurement does not by itself eliminate the possibility that expectations influence ratings. The registry does not report procedures that would allow readers to evaluate this issue further.

What is last observation carried forward?

The population description says missing data were imputed using last observation carried forward (LOCF). In general, LOCF substitutes a participant's most recent available observation for a later missing measurement. This creates a value for an analysis time point when a later score is unavailable, but it relies on an assumption that the carried-forward value is a reasonable representation of what would have been observed. If a participant's underlying condition would have changed after the last recorded assessment, LOCF may not represent that unobserved trajectory. The direction and size of any resulting bias depend on the circumstances and cannot be determined from the method name alone.

The registry's primary-outcome population description says participants had received at least 1 dose and had at least one post-baseline assessment. Thus, the label intent-to-treat in the record is operationalized with those conditions rather than including all enrolled participants irrespective of post-baseline data. The number of participants meeting this definition for the primary endpoint is not reported in the registry record. Further detail about the timing or amount of missing data is not reported in the registry record.

What can be inferred from the safety counts?

Safety counts describe the numbers recorded in the registry, not a comparison of risk between treatment groups. Because this is a single-group study, there is no concurrent comparator for estimating relative differences. Counts also need context, including how events were defined, how long participants were observed, and whether events were judged related to treatment. Those details are not fully reported in the registry record. The figures should therefore be read as descriptive summaries of events in the recorded group.

What about significance testing and planning?

The registry does not report a primary-outcome test statistic, p-value, confidence interval, or complete statistical plan. There are no analysis entries in the registry record. General statistical planning illustrations, when based on an assumed effect and a chosen significance level, describe sample sizes under those assumptions; they are not observed power and do not establish what the study found. The record's planning assumptions refer to a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a fraction of the observed effect. Those are planning conventions, not evidence that this single-group trial made a randomized two-arm comparison. Any calculation requiring an observed effect cannot resolve the absent primary result.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists the primary PANSS total-score change and a range of secondary outcomes. These include PANSS Marder subscale changes, a threshold-based PANSS improvement outcome, Personal and Social Performance, Global Assessment of Functioning, Clinical Global Impression-Severity, Short-Form 36, treatment satisfaction, and sleep quality and daytime drowsiness. Considering multiple outcomes creates a general statistical issue: when many hypotheses are tested, the chance of at least one apparently unusual result can increase if no adjustment or interpretation strategy is specified. Whether and how to address that issue depends on the analysis plan and the purpose assigned to each outcome.

Multiplicity procedures, any hierarchy among outcomes, and any distinction between confirmatory and exploratory analyses are not reported in the registry record. The record lists nine outcome measures and no analysis entries. It does not report enough information to determine which outcomes were formally tested, whether any testing adjustment was used, or how missing results should be interpreted. In particular, the list of outcomes alone does not establish that each was analyzed or that each was intended to support a separate confirmatory claim.

The primary-outcome population description specifies participants who received at least 1 dose and had at least one post-baseline assessment. Missing data were imputed using LOCF. This is the available description of the primary analysis population and missing-data approach. The number included in the primary calculation, the amount and timing of missingness, and any sensitivity analyses are not reported in the registry record. Details of analysis populations for secondary outcomes are not reported in the registry record.

In general, sensitivity analyses examine whether conclusions depend on assumptions such as how missing values are handled. Their presence or absence cannot be inferred from a stated imputation method. Likewise, the absence of a reported multiplicity plan does not establish that no such plan existed outside the registry; it means the registry record does not describe one. With no numerical outcome results or analysis entries, neither multiplicity handling nor the robustness of the results can be evaluated.

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 2% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: cellulitis (0.3%), fall (0.3%), blood electrolytes abnormal (0.3%), hepatic neoplasm malignant (0.3%), haemorrhage intracranial (0.3%).

The registry lists 299 participants at risk in the paliperidone ER group. It records 11 participants with serious adverse events and 180 with other adverse events. These are descriptive counts for the single study group, not estimates of excess risk compared with a control group. Because there is no concurrent comparator, the counts cannot establish whether the event frequency differed from what would have occurred under another treatment or without the study intervention.

The listed serious-event terms are cellulitis, fall, blood electrolytes abnormal, hepatic neoplasm malignant, haemorrhage intracranial, and pregnancy. Each is listed as 0.3%. These term-level percentages should be read as registry summaries; the record does not provide enough detail to determine the full clinical circumstances, timing, or treatment attribution for each event. The presence of an event during a study does not by itself establish that the intervention caused it.

The death count is not reported in the registry record. Definitions of serious and other adverse events, follow-up duration for safety, and details of how events were assessed are not reported in the registry record. The counts are useful for describing what the record lists, but they do not support comparative safety conclusions or a complete account of individual participants' experiences.

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

The study record defines a question about symptom-score change after transition to flexibly dosed paliperidone ER in participants with schizophrenia previously unsuccessfully treated with other oral atypical antipsychotic medication. It also documents a completed, prospective, open-label, single-group study with 299 participants enrolled. These design and population details help readers understand the setting in which the outcomes were intended to be assessed.

What the registry does not provide is the numerical primary result. The mean change in PANSS total score at Week 24, its standard deviation, and the number contributing to that estimate are not reported in the registry record. Consequently, the record does not show whether the average score rose or fell, how large any change was, or how precisely it was estimated. The endpoint description and study completion status cannot substitute for those results.

Even if a within-group change were available, the single-group design would limit its interpretation. A change from baseline would describe the observed participants over time, but without a concurrent control it would not isolate the effect attributable to paliperidone ER. The open-label design also means treatment was not masked. These are limits on causal interpretation, not proof that any particular source of bias affected the findings.

The listed secondary outcomes and adverse-event counts add context about the domains recorded, but numerical secondary results are not reported in the registry record. The safety counts should not be interpreted as comparisons, and the absence of a reported death count does not establish that there were no deaths. The record also does not describe enough analytic detail to assess multiplicity, sensitivity to missing-data assumptions, or the precision of estimates.

In short, the registry supports a description of the study's aims, design, outcome definitions, and selected safety counts. It does not support a conclusion about the size or certainty of the primary symptom change, or a causal comparison with another treatment. Those questions require outcome estimates and supporting analysis information that are not reported in the registry record.

13. Why This Trial Matters Statistically

This study is statistically informative as an example of how a clinical question and a numerical outcome are not the same thing. The registry defines an outcome, a measurement scale, a follow-up time, and an analysis population. Those details explain what was intended to be measured. But without the numerical result and its variability, readers cannot judge the observed magnitude or precision. Clear endpoint definitions are valuable, yet they do not replace reported estimates.

The design also illustrates the distinction between describing change and estimating a treatment contrast. A single-group study can track a cohort over time and report its trajectory. It does not provide the concurrent comparison needed to separate treatment-associated change from other influences as reliably as a randomized comparison can. That distinction is especially important when a study's central question concerns maintained efficacy, because a within-group observation and a comparative effect answer different statistical questions.

The primary endpoint uses a structured symptom scale, while the secondary outcomes cover functioning, global assessment, quality of life, treatment satisfaction, and sleep. These measures represent different outcome domains and should not be treated as interchangeable. A result on one scale would not, on its own, summarize all aspects of participants' experience. In this record, numerical results for those outcomes are not reported in the registry record.

Finally, the stated LOCF approach illustrates that missing-data methods carry assumptions. A method can be named without enough information to judge how much missing data occurred or whether conclusions were robust to alternative assumptions. Reporting participant counts, estimates, uncertainty, and analysis choices is important for making a result interpretable. Here, the missing primary estimate is the main statistical constraint: the design can be described, but the primary outcome's direction, magnitude, and precision cannot be assessed.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The most direct limitation of the registry record is that it does not report the numerical primary endpoint result. Although the endpoint is defined as change from baseline in PANSS total score at Week 24, the mean change, standard deviation, and number evaluable are not reported in the registry record. Without these, the primary outcome cannot be quantitatively interpreted. Confidence intervals, p-values, and other inferential results are also not reported in the registry record.

The study is recorded as single-group, open-label, and without allocation. There is no concurrent control group, so the design does not support a randomized treatment contrast. Any baseline-to-follow-up comparison would be vulnerable to influences that change over time independently of the study intervention. Open-label assessment is another interpretive consideration for outcomes involving symptom ratings. The record does not report further procedures that would clarify how these issues were addressed.

The population is limited to participants with schizophrenia previously unsuccessfully treated with other oral atypical antipsychotic medication. The number enrolled is recorded, but the number included in the primary analysis is not reported in the registry record. Information about prior treatment histories, eligibility details, dose exposure, and participant characteristics is not reported in the registry record. These omissions limit assessment of how broadly the study population can be understood.

The primary population description includes only participants who received at least 1 dose and had at least one post-baseline assessment, and it states that missing values were imputed using LOCF. The amount and pattern of missing data, the number of values imputed, and sensitivity analyses are not reported in the registry record. Statistical methods for secondary outcomes, multiplicity handling, and any analysis adjustments are also not reported in the registry record.

Safety information is limited to recorded counts and selected serious-event terms. Comparative safety cannot be assessed in a single-group study, and event definitions, attribution, and the death count are not reported in the registry record. Together, these limitations mean the record describes the study structure more fully than its outcome evidence.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: An Efficacy, Safety And Tolerability Study of Flexibly Dosed Paliperidone Extended-Release (ER) in Participants With Schizophrenia — NCT00757705.
• Registry record last updated 2014-02-06; status last verified 2014-02.
• Results first posted 2014-02-06.
• 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

NCT00757705 is a completed Phase 4, prospective, open-label, single-group study of flexibly dosed paliperidone extended-release in participants with schizophrenia previously unsuccessfully treated with other oral atypical antipsychotic medication. Johnson & Johnson Taiwan Ltd is listed as sponsor. The record lists 299 participants enrolled, a study start of 2008-03, and primary completion in 2009-05.

The primary outcome was change from baseline in PANSS total score at Week 24. The registry describes an analysis population requiring at least 1 dose and at least one post-baseline assessment, with missing data imputed using LOCF. The numerical primary result and the number evaluable are not reported in the registry record. Secondary outcomes span symptoms, functioning, global assessment, quality of life, satisfaction, and sleep, but their numerical results are not reported in the registry record.

The safety record lists 11 participants with serious adverse events and 180 with other adverse events among 299 at risk. The death count is not reported in the registry record. The single-group, open-label design supports descriptive interpretation of outcomes within the enrolled group but does not provide a concurrent treatment comparison.