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 An Early Safety and Efficacy Study of Ascites Management: Standard Paracentesis or Early Intervention With Pleurx Catheters in Patients With Malignant Ascites (NCT01077063), a randomized na study. The primary outcome is Safety of Pleurx Catheter or Paracentesis.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01077063 |
| Phase | NA |
| Condition | Malignant Ascites |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 7 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins |
| Results posted | Yes |
2. Clinical Question
Population
People with malignant ascites were eligible for the study. The registry’s condition is malignant ascites, and its brief description identifies the intended population as patients with this condition. Further eligibility criteria and participant characteristics are not reported in the registry record.
Intervention
The intervention was a Pleurx catheter, described as a catheter drainage system that the subject uses himself or herself. The study assessed early intervention with the catheter in a controlled prospective setting. The registry does not give further details about catheter placement, drainage schedules, or accompanying care.
Comparator
The comparison was standard therapeutic paracentesis, described in the registry as a cutting and draining procedure for malignant ascites. The study was randomized and used a parallel-group model, with no masking. The registry does not provide further details about the procedure schedule or other care received in either arm.
Primary question
The primary question concerned safety: whether the Pleurx catheter procedure or paracentesis was associated with unacceptable toxicities, defined as life-threatening complications related to the procedure. The specified examples were peritonitis, perforation, or death related to the procedure. The registry records a primary outcome measure for events over 3 years, but does not report an analyzable comparison of that outcome between the groups.
3. Trial Design
This was a randomized, parallel-group study comparing paracentesis with a Pleurx catheter in people with malignant ascites. The registry lists the study as open label, meaning masking was not used. It gives the phase as NA. The listed enrollment is 7, and the study status is terminated. The registry identifies the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins as sponsor.
The study’s brief description says its purpose was to assess the safety of Pleurx catheters and standard therapeutic paracentesis in a controlled prospective setting. The intervention descriptions distinguish a cutting and draining procedure from a catheter drainage system used by the subject. The record does not report the randomization method, allocation concealment, detailed treatment schedules, or rules for changing or stopping assigned treatment. Those design details therefore cannot be assessed from the registry record.
The listed start is 2010-02, and the primary completion is 2013-08. The primary endpoint timeframe is 3 years. These registry dates and the stated endpoint timeframe describe the planned or recorded study timeline; they do not establish how long each participant was followed. Participant-level follow-up durations and the reasons for termination are not reported in the registry record.
The registry lists one primary outcome measure but no analysis records. It also indicates that the primary outcome has several categories or time points and was not reduced to one comparison. As a result, the design can be described, but the posted information does not support an estimate of the primary safety contrast between arms.
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 | Pleurx Catheter | Paracentesis |
|---|---|---|
| STARTED | 4 | 3 |
| COMPLETED | 0 | 0 |
| NOT COMPLETED | 4 | 3 |
Reasons for not completing this period:
| Reason | Pleurx Catheter | Paracentesis |
|---|---|---|
| Adverse Event | 3 | 0 |
| Death | 1 | 1 |
| Withdrawal by Subject | 0 | 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.
Population: subjects with malignant ascites
| Characteristic | Unit | Paracentesis | Pleurx Catheter | Total |
|---|---|---|---|---|
| Participants analysed | 3 | 4 | 7 | |
| Age, Continuous | years | 53.67 (42 to 62) | 55 (45 to 70) | 54.42 (42 to 70) |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | 3 | 6 |
| Age, Categorical: >=65 years | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Female | Participants | 1 | 1 | 2 |
| Sex: Female, Male: Male | Participants | 2 | 3 | 5 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 0 | 1 |
| Race (NIH/OMB): White | Participants | 2 | 4 | 6 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 | 0 | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 3 | 4 | 7 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 3 | 4 | 7 |
6. Primary Endpoint
The registry lists the primary outcome as Safety of Pleurx Catheter or Paracentesis, measured over 3 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | events |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “Safety of Pleurx Catheter or Paracentesis.” Its unit is events, its parameter is a number, and its timeframe is 3 years. The description defines unacceptable toxicities as life-threatening complications related to the procedure, with peritonitis, perforation, or procedure-related death given as examples. The endpoint is intended to capture serious harms associated with either procedure, rather than symptom relief or another measure of ascites control.
In general, a safety endpoint helps make the harms a study is designed to monitor explicit. A clear definition can guide which events count and how their relationship to a procedure is considered. Here, however, the registry does not report the primary endpoint’s event counts by group or an analysis comparing the groups. It also does not provide event-level details to show which recorded adverse events met the endpoint definition or were judged procedure-related.
The registry notes that the primary outcome has several categories or time points and was not reduced to one comparison. Thus, the endpoint definition is available, but the posted record does not provide a single interpretable primary-outcome estimate. The adverse-event figures should not be treated as a substitute for that missing endpoint comparison.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The study addresses a clinically relevant safety comparison: standard paracentesis versus early intervention with a Pleurx catheter for malignant ascites. Its randomized, parallel-group design is suitable in principle for comparing assigned approaches. The record also makes clear that the study was unmasked. These design features identify the intended comparison, but they do not by themselves establish what the results were.
The main interpretive limitation is that the registry reports no analysis records and does not reduce the primary outcome to a single comparison. Although the primary outcome is defined as a count of events over 3 years, no group-specific result for that endpoint is present in the record. There is consequently no reported effect estimate, confidence interval, or significance test for the primary safety question. The registry’s adverse-event listings do not fill that gap: they are not presented as the primary endpoint analysis, and their relationship to the endpoint definition is not established for each event.
The adverse-event record lists serious events affecting 1 of 3 participants at risk in the paracentesis group and 3 of 4 at risk in the Pleurx Catheter group. It also lists other events affecting 3 of 3 at risk in the paracentesis group and 4 of 4 at risk in the Pleurx Catheter group. These are descriptive registry figures. They do not, by themselves, show that events were caused by the procedure, satisfy the primary endpoint definition, or differ reliably between the assigned approaches. The record does not report deaths in these adverse-event group entries.
Precision is a central concern when interpreting any estimate from a study with listed enrollment of 7. In general, limited observations make estimates more sensitive to the outcomes of individual participants, and uncertainty can be substantial. Here, the absence of a primary comparison means that even a confidence interval cannot be interpreted or assessed for precision. No p-value for the primary endpoint is reported.
The study status is terminated, but the reason for termination and its implications for outcome collection are not reported in the registry record. The posted information therefore supports a description of the trial design and recorded adverse-event entries, not a conclusion that one procedure is safer or less safe than the other. A valid comparative conclusion would require the endpoint results, their analysis, and enough information about outcome ascertainment and follow-up to interpret them.
9. Statistical Methods Explained
The registry describes a randomized, parallel-group study with no masking. In general, random assignment is intended to make treatment groups comparable on average with respect to both measured and unmeasured characteristics. It does not guarantee balance in every particular trial, especially when the study has limited enrollment. The record does not state how the random sequence was generated, how assignment was concealed, or whether assignment was stratified. Those details are not reported in the registry record.
What does randomization establish?
Randomization describes how participants are allocated; it does not replace outcome reporting. To interpret a randomized comparison, readers need the outcome counts or estimates in each arm, a clear analysis population, and a method for quantifying uncertainty. The record does not include an analysis of the primary endpoint, so the intended benefit of randomization cannot be evaluated through a reported primary-outcome comparison. The registry also does not report whether the analysis followed the assigned groups regardless of treatment received.
How should a count endpoint be analyzed?
The primary endpoint is described as a number of events. In general, count outcomes can be analyzed using methods suited to event counts, with the choice depending on how events arise, the observation time, and whether participants can experience more than one event. A count model may need to account for over-dispersion when variation in the observed counts is greater than the model’s assumptions allow. This matters because an unsuitable variance assumption can make uncertainty estimates too narrow or too wide. The registry does not report the event-level data, the distribution of counts, a count model, or any model assumptions, so it is not possible to determine what statistical approach would be appropriate for the primary endpoint.
The endpoint description also includes several categories or time points, and the registry indicates that it was not reduced to one comparison. In general, multiple categories or repeated time points can create multiple possible contrasts. A prespecified primary contrast helps distinguish the main question from exploratory comparisons. The record does not report a single contrast, a hierarchy among categories, or an analysis plan for handling multiple comparisons.
What does a confidence interval contribute?
In general, a confidence interval gives a range of values compatible with the data and the statistical model at a stated confidence level. It conveys precision as well as the direction and size of an estimated contrast. A narrow interval indicates greater precision than a wide interval, though its interpretation still depends on the study design, measurement quality, and model assumptions. No primary-outcome estimate or confidence interval is reported in the registry record. There is therefore no interval to use when assessing the range of plausible safety differences.
A p-value, in general, measures how unusual data at least as incompatible with a specified null hypothesis would be under the assumptions of a statistical model. It is not a measure of the probability that the null hypothesis is true, nor does it measure clinical importance. No primary-outcome p-value or test is reported. The absence of a reported test should not be replaced by an informal comparison of the adverse-event figures.
What do the planning assumptions mean?
The registry’s planning description states that its sample-size illustration uses a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a stated fraction of the observed effect. It distinguishes total-event planning for time-to-event tables from participants-per-arm planning for other outcomes. These are planning assumptions, not results from the trial. In general, a planning calculation describes the sample size associated with specified assumptions; it does not establish that the completed study had adequate power or that an effect was observed. The record does not report the trial’s own sample-size justification, and the available information does not yield a primary-outcome effect for interpreting such planning illustrations.
In general, power is the probability of detecting an effect of a specified size under a particular design and set of assumptions. It is not a retrospective measure of whether a study’s result is true. Sample-size illustrations based on an observed effect are especially dependent on that effect estimate and its uncertainty. Because the primary outcome was not reduced to one comparison and no analysis is reported, such calculations should be treated as planning illustrations only, not as observed power or evidence for a treatment effect.
The record does not report interim analyses, stopping boundaries, a statistical analysis plan, or model diagnostics. Those omissions limit assessment of whether analyses were prespecified and whether assumptions were checked. No recalculated primary comparison is available, and there is no sponsor analysis of the primary endpoint in the posted results to take precedence over a recalculation.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome is described as having several categories or time points, and the registry states that it was not reduced to one comparison. That leaves the primary contrast unclear. In general, testing multiple outcomes, categories, or time points increases the chance of finding an apparently notable result by chance if each is tested independently at the same threshold. A prespecified testing strategy can control or explain this issue. No multiplicity strategy is reported in the registry record.
The registry lists one primary outcome measure and no analysis records. It does not report group-specific primary endpoint results, a statistical test, or an estimate with uncertainty. Without a stated contrast and analysis, it is not possible to determine whether the endpoint was analyzed across categories, at particular time points, or in another way. Interim analyses and any adjustments for them are not reported in the registry record.
The record does not report the analysis population, participant flow by arm, withdrawals, protocol deviations, or missing primary outcome data. In general, missing outcomes can affect a comparison if the likelihood of missingness differs between groups or is related to participants’ outcomes. The amount and handling of missing data should therefore be reported, along with the population included in each analysis. Those details are not reported in the registry record.
The study’s terminated status does not establish why it ended or whether planned outcome collection was completed. The reason for termination, any changes to the outcome plan, and the handling of incomplete follow-up are not reported in the registry record. These unknowns prevent assessment of whether the posted safety entries represent complete ascertainment over the stated 3-year timeframe.
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 |
|---|---|---|---|
| Paracentesis | 1 | 3 | 33.3% |
| Pleurx Catheter | 3 | 4 | 75.0% |
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 |
|---|---|
| Paracentesis | 3 of 3 |
| Pleurx Catheter | 4 of 4 |
Most frequent serious adverse event terms
| Event term | Organ system | Paracentesis | Pleurx Catheter |
|---|---|---|---|
| nausea | Gastrointestinal disorders | 0 of 3 | 1 of 4 |
| vomiting | Gastrointestinal disorders | 0 of 3 | 1 of 4 |
| abdominal cramps | Gastrointestinal disorders | 0 of 3 | 1 of 4 |
| infection (non septic) | Infections and infestations | 0 of 3 | 1 of 4 |
| bowel obstruction | Gastrointestinal disorders | 0 of 3 | 1 of 4 |
| fatigue | General disorders | 0 of 3 | 1 of 4 |
| sepsis | Infections and infestations | 1 of 3 | 0 of 4 |
| renal failure | Renal and urinary disorders | 1 of 3 | 0 of 4 |
| hypotension | Cardiac disorders | 1 of 3 | 0 of 4 |
| peritonitis | Infections and infestations | 1 of 3 | 0 of 4 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Paracentesis | Pleurx Catheter |
|---|---|---|---|
| ↑ alkaline phosphatase | Investigations | 1 of 3 | 3 of 4 |
| ↑ ALT | Investigations | 2 of 3 | 2 of 4 |
| ↓ lymphocytes | Blood and lymphatic system disorders | 2 of 3 | 2 of 4 |
| ↓ sodium | Metabolism and nutrition disorders | 2 of 3 | 2 of 4 |
| ↑ AST | Investigations | 1 of 3 | 2 of 4 |
| ↑ total bilirubin | Investigations | 1 of 3 | 2 of 4 |
| ↓ albumin | Metabolism and nutrition disorders | 1 of 3 | 2 of 4 |
| ↓ calcium | Metabolism and nutrition disorders | 2 of 3 | 1 of 4 |
| ↓ hemoglobin | Blood and lymphatic system disorders | 1 of 3 | 2 of 4 |
| fatigue | General disorders | 2 of 3 | 1 of 4 |
Serious events with the highest arm-level rate: sepsis (33.3%), renal failure (33.3%), hypotension (33.3%), peritonitis (33.3%), abdominal pain (33.3%).
The adverse-event record lists serious events for the Paracentesis group as 1 of 3 participants at risk affected, and for the Pleurx Catheter group as 3 of 4 at risk affected. For other events, it lists 3 of 3 at risk affected in the Paracentesis group and 4 of 4 at risk affected in the Pleurx Catheter group. These are the registry’s group-level adverse-event entries, not a reported comparison of the primary endpoint.
The record also lists serious-event terms and percentages: sepsis, renal failure, hypotension, peritonitis, and abdominal pain at 33.3% each, and nausea at 25.0%. The record does not establish in this listing which treatment group each term belongs to, whether terms overlap within participants, or whether each event was related to the procedure. Deaths are not reported in the adverse-event group entries.
In general, adverse-event counts describe what was recorded, while causal attribution requires clinical assessment and an explicit definition. These figures should not be equated with the primary endpoint, which is limited to life-threatening complications related to the procedure. The registry does not provide event-level details or a comparative analysis that would connect the adverse-event entries to that endpoint.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, unmasked, parallel-group study was intended to compare paracentesis with a Pleurx catheter for malignant ascites. It defines a safety outcome involving life-threatening complications related to the procedure and gives examples of those complications. It also records adverse events in each group. These details help identify the study question and the kinds of safety information entered in the registry.
What the record does not establish is the comparative result for the primary endpoint. No primary endpoint analysis is reported, and the outcome was not reduced to one comparison. There is no reported estimate of the difference between groups, confidence interval, or test of the primary safety question. The adverse-event entries are descriptive and cannot be substituted for that missing comparison.
The listed event figures should not be interpreted as proof that events were caused by either procedure. Nor do they establish that all recorded serious events met the primary outcome definition. The registry does not provide enough detail to connect the adverse-event terms to specific participants, determine their timing, or assess procedure-relatedness. It also does not report deaths in the adverse-event group entries.
In general, a study’s results are most informative when the outcome definition, analysis population, effect estimate, and uncertainty are all reported. Without these elements, a numerical contrast cannot be judged for precision or robustness. The listed enrollment is 7, but the primary analysis and the completeness of follow-up are not reported. The terminated status alone does not explain whether the study ended early, why it ended, or whether planned data collection was complete.
Accordingly, the posted record supports a description of the study and its recorded safety events, but not a conclusion that either approach is safer. It also does not establish efficacy for controlling ascites. Those questions require comparative outcome results and sufficient information about how they were collected and analyzed.
13. Why This Trial Matters Statistically
This study is statistically notable because it poses a randomized safety comparison but the registry record does not report the primary comparison. That distinction matters: a study design can identify a question and a plan, while only outcome results and their analysis can answer it. Here, readers can identify the assigned approaches, the intended population, and the safety endpoint, but cannot assess a primary effect estimate.
The endpoint itself raises a common analytical issue. It is expressed as a count of events, while its definition includes several serious event types and the registry notes multiple categories or time points. In general, decisions about the unit of analysis, handling of repeated events, follow-up time, and the primary contrast can change how a safety result should be interpreted. Those decisions are not reported in the registry record.
The adverse-event figures also illustrate why descriptive counts should not be mistaken for comparative evidence. In general, a difference in observed counts can reflect chance, differences in follow-up, event ascertainment, or other factors as well as a treatment effect. Statistical uncertainty and adequate outcome detail are needed to distinguish among these explanations. No primary analysis or uncertainty estimate is reported.
The study’s terminated status and listed enrollment make transparent reporting particularly important, but the reason for termination and the completeness of outcome collection are not reported. The registry therefore offers a useful example of the distinction between a stated safety question and a reported answer: design features and event listings alone cannot establish the comparative safety of the two approaches.
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 main trial-specific limitation is the absence of a reported primary endpoint comparison. The registry describes the outcome as a count of events over 3 years but says that it has several categories or time points and was not reduced to one comparison. No primary outcome analysis, effect estimate, confidence interval, or p-value is reported. As a result, the intended safety question remains unanswered by the posted analysis record.
The study is listed as terminated, but the reason for termination is not reported in the registry record. The listed enrollment is 7, and the record does not explain whether recruitment or follow-up ended as planned. Participant flow, arm-specific primary outcome data, follow-up duration, withdrawals, and the completeness of endpoint ascertainment are not reported.
The adverse-event entries do not resolve these limitations. The record does not give event-level descriptions or establish which serious events were life-threatening, procedure-related, or part of the primary endpoint. The relation between the serious-event terms and treatment groups is not specified in the listed terms. Deaths are not reported in the adverse-event group entries.
Further design and analysis details are also absent. The randomization method, allocation concealment, eligibility criteria, outcome adjudication procedures, statistical analysis plan, analysis population, handling of missing data, and any interim analyses are not reported in the registry record. Because masking was not used, outcome assessment could in general be susceptible to differences in ascertainment; the record does not describe safeguards or adjudication that would clarify this concern. These limitations mean that the design and descriptive safety entries can be summarized, but a comparative safety conclusion cannot be drawn from the registry record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: An Early Safety and Efficacy Study of Ascites Management: Standard Paracentesis or Early Intervention With Pleurx Catheters in Patients With Malignant Ascites — NCT01077063.
- Registry record last updated 2015-10-29; status last verified 2015-10.
- Results first posted 2014-09-22.
- 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
NCT01077063 is a randomized, open-label, parallel-group study of paracentesis versus Pleurx catheter use in patients with malignant ascites. The registry lists enrollment of 7, phase NA, and status terminated. The listed study start is 2010-02, and primary completion is 2013-08.
The primary outcome is safety, defined around life-threatening complications related to the procedure, including peritonitis, perforation, or procedure-related death, with a timeframe of 3 years. The registry reports adverse-event entries for both groups but no analysis records. It states that the primary outcome has several categories or time points and was not reduced to one comparison.
The record does not report a primary endpoint estimate, uncertainty interval, or significance test. The reason for termination, analysis population, missing-data handling, and completeness of follow-up are not reported in the registry record. The posted information therefore describes the design and adverse-event entries but does not support a comparative conclusion about safety.