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 Salsalate as an Adjunctive Treatment for Patients With Schizophrenia (NCT01578486), a na phase 4 study. The primary outcome is PANSS Total Score.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01578486 |
| Phase | Phase 4 |
| Condition | Schizophrenia, Schizoaffective Disorder |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 17 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University of Massachusetts, Worcester |
| Results posted | Yes |
2. Clinical Question
Population
The registry lists schizophrenia and schizoaffective disorder as conditions. Its brief summary describes a study in schizophrenia subjects and says a total of 15 subjects would be enrolled. The registry enrollment is 17.
Intervention
Salsalate was used as an adjunctive treatment. The brief summary describes a 12-week study at 3 g/day, and the arm description calls it open-label.
Comparator
There was a single group and no like-for-like control group. Allocation is listed as not applicable, and masking as none.
Primary question
The primary outcome was PANSS Total Score, measured at baseline and 12 weeks. The registry record does not report the score values or the estimated change.
The clinical question is whether PANSS Total Score changed between baseline and 12 weeks among participants receiving adjunctive salsalate. Because the design has one open-label group, it does not directly compare the change under salsalate with change under a control condition. A before-and-after pattern, if reported, would describe the enrolled participants over time; by itself, it would not establish that salsalate caused that pattern.
The registry record also names cognitive functioning and metabolic parameters in its brief summary, and lists Hs-CRP, TNF-alpha, and IL-6 as secondary outcomes. The record identifies eight outcome measures, but it does not provide numerical results for the primary endpoint. It therefore does not establish the direction, magnitude, or precision of the primary outcome change.
3. Trial Design
This was a Phase 4, completed, single-group study sponsored by University of Massachusetts, Worcester. The registry lists a study start of 2011-06 and primary completion of 2015-07. Enrollment is listed as 17. Separately, the brief summary describes a 12-week study and states that a total of 15 subjects would be enrolled. The registry record does not explain the difference between the listed enrollment and the enrollment described in the summary.
The intervention was salsalate as an adjunctive treatment, with the brief summary specifying 3 g/day. The arm description identifies the study as open-label. Masking is listed as none, and allocation as not applicable. With a single group, there is no concurrent control arm in the registry design, so the study is not a randomized comparison.
The primary outcome was PANSS Total Score, with a stated timeframe of baseline and 12 weeks. The registry describes the planned summary measure as a mean with standard deviation. The brief summary also names psychopathology, cognitive functioning, and metabolic parameters as areas of interest. Hs-CRP, TNF-alpha, and IL-6 are listed among the secondary outcomes.
The registry record does not report the recruitment details beyond identifying clinicians at the Freedom Trail Clinic or Massachusetts General Hospital as potential sources of subjects. It does not report a detailed protocol, the number of participants assessed or completing follow-up, or reasons for withdrawal. Those omissions limit the ability to reconstruct participant flow and evaluate how the enrolled group relates to the population described in the study summary.
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: A total of 17 subjects consented and were screened, 4 of which were screen fails. The remaining 13 received the study medication.
Overall Study
| Stage | Salsalate |
|---|---|
| STARTED | 13 |
| COMPLETED | 8 |
| NOT COMPLETED | 5 |
Reasons for not completing this period:
| Reason | Salsalate |
|---|---|
| Physician Decision | 3 |
| Withdrawal by Subject | 2 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Salsalate |
|---|---|---|
| Participants analysed | 8 | |
| Age, Continuous | years | 42.8 (SD 9.8) |
| Sex: Female, Male: Female | Participants | 2 |
| Sex: Female, Male: Male | Participants | 6 |
6. Primary Endpoint
The registry lists the primary outcome as PANSS Total Score, measured over Baseline and 12 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is PANSS Total Score, a continuous score intended to measure positive and negative symptoms of schizophrenia. The registry description says the score combines all subscales of the Positive and Negative Syndrome Scale and has a range of 30-210; higher scores correspond with worse outcomes. The planned reporting measure is the mean and standard deviation, with assessment at baseline and 12 weeks.
As a general statistical explanation, a continuous score can preserve gradations across participants rather than reducing the outcome to a simple yes-or-no category. A mean describes the group’s average score, while a standard deviation describes how spread out individual scores are around that average. Looking at the same measure at baseline and follow-up can describe whether the group’s average score changed over time.
The registry record does not report baseline or 12-week means, standard deviations, a change estimate, or its uncertainty. It is therefore not possible to assess the observed size or precision of any PANSS change from the registry record. The endpoint’s interpretation is also limited by the single-group, open-label design: a change over time would not, on its own, separate an intervention effect from other explanations for change.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies PANSS Total Score as the primary outcome, with measurement at baseline and 12 weeks. It does not report the numerical outcome results. In particular, no baseline mean, follow-up mean, mean change, standard deviation, confidence interval, or significance test result is reported in the registry record. The direction and size of the primary outcome pattern therefore cannot be described, and its precision cannot be judged.
The design matters for interpretation. This was a single-group, open-label study, with allocation listed as not applicable and masking listed as none. There is no concurrent control group against which to compare a change in PANSS Total Score. As a general statistical point, measurements taken before and after an intervention can describe the group’s change over time, but they do not by themselves distinguish an intervention effect from other influences that may also change over time. Open-label assessment may also leave outcome measurement more susceptible to expectations, depending on how the measure was administered; the registry record does not describe the assessment procedures.
The registry lists enrollment as 17, while the brief summary says that 15 subjects would be enrolled. These are different statements in the record, and the record does not explain the distinction. It also does not report the number with primary outcome measurements at each time point, the number completing follow-up, or a participant-flow account. Without those details, the completeness of the primary outcome data cannot be assessed.
The record lists eight outcome measures and zero analyses. It does not provide outcome estimates for PANSS or the listed secondary outcomes. It also does not report the analysis population, the approach to missing observations, or an adjustment for examining multiple outcomes. As a result, neither a comprehensive efficacy interpretation nor a comparison across outcomes is possible from the posted registry information.
The safety record lists eight participants at risk for serious adverse events and zero affected by serious adverse events in the salsalate group. It lists eight at risk and seven affected for other adverse events. These are descriptive figures; the registry does not provide event terms for serious events, and the deaths field is not reported in the registry record. The safety counts do not compensate for the absence of primary outcome results and do not permit a controlled comparison.
9. Statistical Methods Explained
The following concepts are general statistical explanations. The registry record gives the design and the intended primary outcome summary, but does not report the numerical primary outcome analysis.
What does a mean and standard deviation convey?
For a continuous outcome such as PANSS Total Score, the mean is the arithmetic average across the participants included in an analysis. The standard deviation describes the variability of individual scores around that mean. These summaries answer different questions: the mean describes the group’s central level, while the standard deviation describes how similar or different participants’ scores are from one another.
For measurements at baseline and follow-up, separate means describe the group at each time point. A change estimate would describe the difference between those measurements according to the analysis method used. In a repeated-measures setting, the variability of individual changes is not necessarily recoverable from the two time-specific standard deviations alone. The registry record states the intended summary as mean and standard deviation, but does not report the numerical summaries or explain whether the main analysis used individual paired changes.
What would a confidence interval add?
As a general explanation, a confidence interval gives a range of values compatible with an estimate under a specified statistical procedure and its assumptions. It communicates uncertainty around an estimated effect, rather than only indicating whether a significance threshold was crossed. A narrow interval indicates greater precision than a wide interval, though precision does not establish that an estimate is free of bias. No confidence interval for the PANSS outcome is reported in the registry record, so the precision of any change cannot be evaluated.
Why does the single-group design affect the analysis?
In a single-group before-and-after study, the observed change is a within-group pattern over time. General statistical interpretation distinguishes this pattern from a comparison of changes between intervention and control groups. Without a concurrent control group, time-related influences and other changes during follow-up cannot be separated from the intervention using the design alone. Statistical adjustment can address measured factors in some settings, but it cannot create the missing randomized control comparison, and the registry record does not report an adjusted analysis.
The study is described as open-label and masking as none. In general, knowledge of treatment assignment can affect participant reports, clinical interactions, or outcome assessment. The PANSS description identifies what the score measures, but the registry record does not describe who assessed it or how assessment was conducted. No conclusion about the presence or size of any assessment influence can be drawn from the record.
What does the record say about statistical planning?
The registry record does not report the trial’s own sample-size justification or a statistical analysis plan. It does include general assumptions for planning illustrations: two-sided significance level 0.05, equal allocation between two arms, and a normal approximation, with the target effect expressed as a stated fraction of the observed effect. Those assumptions describe planning illustrations, not the design of this single-group study. The registry does not identify a randomized two-arm design, and the stated planning assumptions should not be read as evidence that the trial had two arms.
General sample-size calculations estimate how many participants a hypothetical study might need under specified assumptions about the effect, variability, allocation, and statistical procedure. Such a calculation is a planning exercise. It is not an observed outcome and does not show that a completed study had a particular probability of detecting an effect. No sample-size justification for this trial is reported in the registry record.
How should multiple outcomes be considered?
When a study assesses several outcomes, testing each can increase the chance of obtaining at least one apparently notable result by chance. General statistical approaches can define one primary outcome in advance, adjust for multiple tests, or frame secondary analyses as exploratory. The registry identifies a primary endpoint, lists secondary outcomes, and reports eight outcome measures. It does not report whether multiplicity was addressed or how the outcomes were prioritized in analysis. Consequently, the registry record does not support an assessment of the statistical plan for multiple testing.
The record lists zero analyses and does not give estimates, standard errors, confidence intervals, or test results for the primary outcome. The statistical methods actually used to analyze the primary endpoint are therefore not reported in the registry record. It would be inappropriate to infer an analysis method from the stated mean-and-standard-deviation summary alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies PANSS Total Score as the primary outcome and lists Hs-CRP, TNF-alpha, and IL-6 as secondary outcomes. It also reports eight outcome measures. A primary endpoint can help distinguish the central study question from additional outcomes, but it does not by itself establish how analyses were prioritized or how the interpretation of multiple tests was handled.
As a general statistical point, evaluating multiple outcomes or multiple analyses can make chance findings more likely if each is assessed separately. Researchers may use a prespecified testing hierarchy or another multiplicity approach, but the registry record does not report whether any such approach was planned or used. The record reports zero analyses, and numerical results for the primary and secondary outcomes are not reported in the registry record.
The registry record does not describe missing-data methods, the number of participants with PANSS measurements at baseline or 12 weeks, or the analysis population. It does not report whether participants who discontinued treatment or missed assessments were included in an analysis, or how any incomplete measurements were handled. The listed enrollment of 17 and the brief-summary statement that 15 subjects would be enrolled do not resolve those questions; the record does not explain their relationship.
As a general statistical issue, missing outcomes can affect both the number of observations contributing to an estimate and its interpretation, particularly if the likelihood of missingness is related to participants’ outcomes or experiences. Without participant flow and a stated analysis approach, the extent and consequences of missing primary outcome data cannot be assessed.
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 |
|---|---|---|---|
| Salsalate | 0 | 8 | 0.0% |
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 |
|---|---|
| Salsalate | 7 of 8 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Salsalate |
|---|---|---|
| Headache | General disorders | 2 of 8 |
| Stomach/Abdominal discomfort | Gastrointestinal disorders | 1 of 8 |
| Nausea/Vomiting | General disorders | 1 of 8 |
| Lightheadedness | General disorders | 1 of 8 |
| Weakness | General disorders | 1 of 8 |
| Bloody urine | General disorders | 1 of 8 |
The registry lists eight participants at risk for serious adverse events in the salsalate group and zero affected by serious adverse events. For other adverse events, it lists eight at risk and seven affected. These figures describe the recorded counts in the group; the registry record does not give further detail about the timing, severity, duration, or individual event histories.
No serious adverse-event terms are listed. That means the registry record supplies no serious-event descriptions; it should not be used to infer event details that are not recorded. The deaths field is not reported in the registry record.
These are descriptive safety figures from a single-group study. As a general statistical point, counts in a group do not establish how those outcomes compare with what would have occurred under a different treatment or no study intervention. The record does not provide a control group or a comparative safety estimate. The figures should therefore be read as reported observations in this study group, not as a controlled estimate of risk.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a completed, open-label, single-group study evaluated adjunctive salsalate and identified PANSS Total Score at baseline and 12 weeks as the primary outcome. It also reports enrollment of 17, while the brief summary describes a plan to enroll 15 subjects. The record does not explain that difference.
Most importantly for interpreting the primary question, numerical PANSS results are not reported in the registry record. There is no reported baseline or follow-up mean, change estimate, or measure of uncertainty. The record therefore does not show whether scores increased, decreased, or remained similar, and it does not show how precisely any change was estimated.
Even if a before-and-after result were available, the single-group, open-label design would limit causal interpretation. As a general statistical point, a change observed over time in one group does not isolate the effect of an intervention from other possible influences. There is no concurrent control group in the registry design to provide a direct comparison.
The safety counts describe participants recorded as affected by serious and other adverse events, but they are not a controlled comparison. The registry record also does not report the analysis population, missing-data handling, or multiplicity approach. These gaps limit assessment of how complete and robust any outcome analysis might be.
Accordingly, the registry record supports a description of the study design, intended endpoint, and recorded safety counts. It does not support a conclusion about the direction or magnitude of change in the primary outcome, the precision of an effect estimate, or a causal treatment effect.
13. Why This Trial Matters Statistically
This trial is statistically instructive because it combines a continuous primary outcome measured over time with a single-group, open-label design. PANSS Total Score is described as a mean and standard deviation at baseline and 12 weeks. That setup makes clear why a reported change estimate and its uncertainty would be important: time-specific averages alone describe the group at each time, while an estimate of change directly addresses the stated before-and-after question.
The design also illustrates the distinction between observing change and estimating a comparative effect. In general, a control group can help distinguish changes associated with an intervention from changes that might occur over time for other reasons. This registry record describes no control group, so any within-group pattern would have a narrower interpretation than a randomized comparison.
Reporting completeness is another statistical issue highlighted by the record. It names a primary endpoint and several secondary outcomes, but reports zero analyses and no numerical outcome results. It does not report missing-data procedures, analysis populations, or multiplicity handling. These details matter because they help readers understand which observations and comparisons support an estimate and how uncertainty was addressed.
The record also contains different enrollment statements: a listed enrollment of 17 and a brief-summary plan for 15 subjects. Since the relationship between these figures is not explained, participant flow cannot be reconstructed from the record alone. This illustrates why clear reporting of planned enrollment, actual enrollment, follow-up, and analyzed participants is valuable for interpreting clinical trial results.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The most consequential limitation for statistical interpretation is that numerical results for the primary PANSS outcome are not reported in the registry record. Although the endpoint and its timeframe are specified, the record gives no means, standard deviations, change estimate, or uncertainty interval. The primary outcome’s direction, magnitude, and precision therefore cannot be assessed.
The single-group, open-label design has no concurrent control comparison. As a general limitation, a before-and-after pattern cannot by itself distinguish an intervention effect from other influences operating over the study period. The registry record does not report procedures that might further clarify outcome assessment or reduce the potential influence of open-label knowledge.
The record lists enrollment as 17, while the brief summary says a total of 15 subjects would be enrolled. It does not explain the relationship between those figures. It also does not report participant flow, numbers completing follow-up, or the number contributing data to the primary endpoint at each time point.
Additional limitations are that the analysis population, statistical methods, missing-data procedures, sample-size justification, and multiplicity approach are not reported in the registry record. The record lists eight outcome measures and zero analyses, but gives no numerical outcome results for the primary endpoint or the listed secondary outcomes. These omissions prevent evaluation of the analyses and of the completeness of the reported evidence.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Salsalate as an Adjunctive Treatment for Patients With Schizophrenia — NCT01578486.
- Registry record last updated 2018-05-08; status last verified 2018-04.
- Results first posted 2018-05-08.
- 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.
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18. Record Summary
The registry describes a completed Phase 4, single-group, open-label study sponsored by University of Massachusetts, Worcester. The intervention was adjunctive salsalate; the brief summary specifies 3 g/day over 12 weeks. Schizophrenia and schizoaffective disorder are listed as conditions. The primary outcome was PANSS Total Score at baseline and 12 weeks, with a planned summary as mean and standard deviation.
Enrollment is listed as 17, while the brief summary states that 15 subjects would be enrolled; the registry record does not explain the difference. It lists eight outcome measures and zero analyses. Numerical results for PANSS and the secondary outcomes are not reported in the registry record.
For safety, the record lists eight participants at risk and zero affected by serious adverse events, and eight at risk and seven affected by other adverse events. No serious-event terms are listed, and deaths are not reported in the registry record. The single-group design does not provide a control comparison.