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 The Pristine Post-Market Study (NCT05228132), a na na study. The primary outcome is Overall Complication Rate of the Pristine™ Catheter.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05228132 |
| Phase | NA |
| Condition | Kidney Failure, Chronic, Hemodialysis Complication, Hemodialysis Catheter Infection |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 142 |
| Arms in the primary outcome | n/a |
| Lead sponsor | C. R. Bard |
| Results posted | Yes |
2. Clinical Question
The study concerned the safety and performance of the Pristine™ Long-Term Hemodialysis Catheter in people with chronic kidney disease requiring long-term hemodialysis access. It was prospective, multi-center, and single-arm; the registry does not describe a concurrent control group.
Population
People with chronic kidney disease who required hemodialysis access. The registry lists kidney failure, hemodialysis complications, catheter infection, access failure, central venous catheter-related bloodstream infection, and end-stage renal disease among the conditions of interest. Further eligibility details are not reported in the registry record.
Intervention
The Pristine™ Long-Term Hemodialysis Catheter, a device described as a chronic hemodialysis catheter with a dual-lumen radiopaque shaft and pre-formed split tip. The study assessed this device in routine clinical follow-up; additional procedural details are not reported in the registry record.
Comparator
There was no randomized or concurrent comparison arm in the registry description. The primary endpoint was to be evaluated against a performance goal derived from Dialysis Outcomes and Practice Patterns Study data, rather than against a concurrently enrolled control group. The goal’s numerical value is not reported in the registry record.
Primary question
At 3 months after the index procedure, what was the overall rate of infectious and non-infectious complications requiring revision to maintain patency and improve access performance? The endpoint analysis was not performed because no participants were followed to the 3-month follow-up.
The registry lists enrollment as 142, but that does not establish how many participants contributed data to any particular outcome. The reported safety group has 7 participants at risk. Those figures describe different aspects of the record and should not be treated as interchangeable.
3. Trial Design
The Pristine Post-Market Study is registered as a prospective, multi-center, single-arm clinical study of a hemodialysis catheter. It is classified as phase NA, with allocation NA, no masking, and a single-group model. These labels describe a design without a randomized comparator or blinded assessment in the registry record; they do not establish what procedures were or were not used beyond the information recorded.
The registry lists enrollment as 142. The listed study start date is 2022-05-16, and the primary completion date is 2022-09-21. The record status is terminated. It does not explain the reason for termination, the timing of that decision, or whether enrollment reached the listed total. Those details are not reported in the registry record.
The primary endpoint was defined as a combined rate of infectious and non-infectious complications requiring revision to maintain patency and improve access performance. It was scheduled for assessment at 3 months after the index procedure and compared with a performance goal derived from Dialysis Outcomes and Practice Patterns Study data. No participants were followed to that follow-up, so the primary endpoint analysis was not performed.
The registry names secondary outcomes concerning freedom from catheter-related bloodstream infection, freedom from device- and/or procedure-related adverse events, technical success, participant survival, catheter survival, and patency. It lists 8 outcome measures overall and 0 analyses. The analysis methods and results for the secondary outcomes are not reported in the registry record. Further information on visit schedules, outcome adjudication, participant flow, and the statistical analysis plan is not reported in the registry record.
A single-arm study can describe events among participants receiving the device, but it cannot by itself provide a randomized comparison with another device or care strategy. A performance goal offers a different type of reference: it is a benchmark, not a concurrent group assigned under the same study conditions. The registry’s stated benchmark source is DOPPS; its exact value and derivation 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
| Stage | Pristine™ Long-Term Hemodialysis Catheter |
|---|---|
| STARTED | 7 |
| 1-Month Follow-up | 2 |
| 3-Month Follow-up | 0 |
| 6-Month Follow-up | 0 |
| 12-Month Follow-up | 0 |
| COMPLETED | 0 |
| NOT COMPLETED | 7 |
Reasons for not completing this period:
| Reason | Pristine™ Long-Term Hemodialysis Catheter |
|---|---|
| Investigation Early Termination by Sponsor | 2 |
| Adverse Event | 3 |
| Lost to Follow-up | 1 |
| Arteriovenous-fistula mature | 1 |
Analysis population for the primary outcome, as defined in the registry: No participants were followed out to the 3-Month follow-up thus the primary endpoint analysis was not performed. With no source verification or analysis performed, there may be inaccurate reporting and potential misrepresentation of the result.
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 | Pristine™ Long-Term Hemodialysis Catheter |
|---|---|---|
| Participants analysed | 7 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 5 |
| Age, Categorical: >=65 years | Participants | 2 |
| Sex: Female, Male: Female | Participants | 4 |
| Sex: Female, Male: Male | Participants | 3 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 0 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 7 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 5 |
| Race (NIH/OMB): White | Participants | 1 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Region of Enrollment: United States | participants | 7 |
6. Primary Endpoint
The registry lists the primary outcome as Overall Complication Rate of the Pristine™ Catheter, measured over At 3 months post index procedure..
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint combined infectious complications with non-infectious complications that required revision to maintain patency and improve access performance. It was to be assessed at 3 months after the index procedure. The endpoint therefore focused not simply on whether a complication occurred, but on complications meeting the stated criteria and requiring revision.
In general, a combined endpoint can represent several clinically relevant event types in one measure. It may also obscure differences among those types: the combined rate alone would not show how much each component contributed. For this endpoint, the registry does not report component-specific results or a method for handling participants who experienced more than one qualifying complication.
The endpoint was to be evaluated against a performance goal derived from DOPPS data. In general, a benchmark allows a single-arm study to compare an observed outcome with a prespecified reference, but it is not equivalent to a concurrently randomized control. The benchmark value and its statistical uncertainty are not reported in the registry record.
No participants were followed to the 3-month assessment, and the primary endpoint analysis was not performed. Consequently, the record does not provide an observed primary endpoint rate or an estimate of how precisely that rate was measured.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the primary endpoint has no analysis. The registry states that no participants were followed to the 3-month follow-up and that the primary endpoint analysis was not performed. There is therefore no posted primary complication-rate estimate to compare with the performance goal. The study’s stated primary question remains unanswered by the registered endpoint results.
The enrollment entry of 142 does not change that conclusion. Enrollment and endpoint follow-up are distinct: a participant can contribute to enrollment without contributing an observation at a later endpoint visit. The registry specifically reports no participants followed to the 3-month assessment. It does not provide a participant flow accounting for enrollment, discontinuation, or follow-up at other times.
The record lists a safety group of 7 at risk, with 3 participants affected by serious adverse events and 2 affected by other adverse events. These figures are not an estimate of the primary endpoint, which was not analyzed. Nor should the safety group’s denominator be replaced by the enrollment entry. The record does not report the duration or completeness of safety observation for this group.
Two serious adverse event terms are listed at 14.3% each: “Not Device Related-Septic Shock” and “Device Related-Thrombosis in device.” These entries describe the terms and percentages recorded; they do not supply the missing primary endpoint result. The registry also lists 0 deaths in the safety group. Interpretation of these safety data is limited by the small reported group and by the absence of further information about exposure, event timing, participant overlap, and ascertainment.
The study’s single-arm design also limits what any event rate could establish. A rate among participants using the catheter would describe observed experience in that study, while comparison with a historical performance goal would depend on the goal’s definition and comparability. The exact goal, the planned statistical test, and any uncertainty interval are not reported in the registry record. No randomized contrast is available in the design description.
In general, statistical precision depends on the amount and completeness of outcome information, as well as on the event rate and analysis method. Here, the planned primary follow-up did not occur, so precision for the primary endpoint cannot be assessed from a reported estimate. The record’s warning that reporting may be inaccurate or potentially misrepresentative, given the absence of source verification or analysis, is an additional reason to read the posted entries cautiously. It does not provide a basis for inferring an unreported primary result.
9. Statistical Methods Explained
The registry describes a single-group study and a primary outcome that was intended to be compared with a performance goal. It does not report a completed primary endpoint analysis. The statistical ideas below explain how such an analysis could generally be interpreted; they should not be read as a description of methods actually used in this study.
What does a single-arm rate represent?
In general, an event rate in a single-arm study describes the observed frequency of a defined event among participants with relevant follow-up. Its interpretation depends on the event definition, the observation period, the denominator, and the completeness of follow-up. For the Pristine catheter study, the primary event definition and 3-month timeframe are stated, but no participants reached that follow-up and no endpoint rate was calculated. The denominator and method intended for the primary analysis are not reported in the registry record.
A single-arm rate is not a treatment contrast. Without a concurrent comparator, differences in participant characteristics, care, event ascertainment, or follow-up cannot be separated from differences attributable to the device. A historical performance goal can provide a benchmark, but its relevance depends on how it was constructed and how comparable the populations and outcome definitions are. The registry names DOPPS as the source for the goal, but the value, derivation, and planned comparison procedure are not reported in the registry record.
What would a confidence interval add?
In general, a confidence interval expresses uncertainty around an estimated quantity under a specified statistical method. For an event rate, the interval can help readers distinguish a relatively precise estimate from one that is compatible with a wide range of underlying rates. It does not resolve bias from missing follow-up, outcome misclassification, or a non-comparable benchmark. Because no primary endpoint estimate was produced, there is no primary-rate confidence interval to interpret. The registry does not report confidence intervals for the described safety figures.
Why does follow-up matter?
The endpoint was defined at 3 months after the index procedure. Participants without follow-up to that time cannot simply be assumed to have had no complications. In general, excluding participants without endpoint data can change the interpretation if missingness is related to health, device experience, or other factors. Other approaches require explicit assumptions and a prespecified analysis. The registry reports no participants followed to the 3-month visit and does not report an imputation method, a missing-data strategy, or a sensitivity analysis. Thus, no statistical adjustment can be inferred from the record.
What can the safety counts show?
In general, counts of participants affected by adverse events describe observed safety reports in a defined group; they are not necessarily counts of unique event episodes. The record gives 7 at risk, 3 affected by serious adverse events, and 2 affected by other adverse events for the catheter group. It does not explain whether individuals could appear in both categories, how long they were observed, or whether events were counted by participant or episode for each listed term. These counts should therefore be read as registry-reported summaries, not as a complete analysis of incidence over a common exposure period.
Over-dispersion is a general issue that can arise when event counts vary more than a statistical model expects. In such settings, a simple model may understate uncertainty. The registry does not report a count model or any assessment of over-dispersion, and the primary endpoint analysis was not performed. This concept cannot be used to infer an analysis method for this study.
What do the planning assumptions mean?
The registry describes a sample-size planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It also states that the effect to detect is expressed as a fraction of the observed effect; for time-to-event outcomes, the illustration uses a total event count, while other illustrations refer to participants per arm. These are planning conventions, not evidence that the study used a two-arm design or achieved a particular power.
The registered study is single-arm, and the primary endpoint analysis was not performed. The planning assumptions therefore must not be mistaken for the trial’s design, observed power, or a completed inference. The registry does not report the study’s own sample-size justification or statistical analysis plan. Any calculated sample-size values associated with a planning illustration are planning aids, not observed outcomes or a substitute for the missing endpoint analysis.
How should a performance-goal comparison be read?
In general, a performance-goal analysis asks whether an observed outcome is sufficiently compatible with, or differs from, a benchmark under a specified statistical procedure. Its interpretation depends on the benchmark’s value, the direction and decision criterion, the sampling model, and uncertainty in the benchmark itself. Those details are not reported in the registry record. No conclusion about meeting or failing the goal can be drawn when the primary outcome was not analyzed.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 8 outcome measures and 0 analyses. It names secondary outcomes related to freedom from catheter-related bloodstream infection, freedom from device- and/or procedure-related adverse events, technical success, overall participant survival, overall catheter survival, and overall patency. The analysis methods and results for these outcomes are not reported in the registry record.
When a study evaluates multiple outcomes, multiplicity can arise because repeated statistical tests increase the chance of at least one apparently notable finding by chance. In general, a statistical plan may prioritize an endpoint, adjust for multiple comparisons, or interpret secondary analyses as exploratory. The registry does not report a multiplicity strategy, a hierarchy among outcomes, or whether any secondary analyses were planned. With no analyses listed, there are no posted outcome tests to interpret as a family of results.
Missing follow-up is especially consequential for the primary endpoint: the record states that no participants were followed to 3 months, so that analysis was not performed. The number of participants with data at other time points, reasons for missingness, and follow-up completeness for secondary outcomes are not reported in the registry record. No approach to imputation, censoring, or sensitivity analysis is reported.
The analysis populations are also not described. It is not reported in the registry record whether an intention-to-treat, per-protocol, safety, or other population was prespecified for each outcome. The safety group’s 7 participants at risk should not be assumed to define the analysis population for other outcomes. Interim analyses and stopping rules are not reported in the registry record.
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 |
|---|---|---|---|
| Pristine™ Long-Term Hemodialysis Catheter | 3 | 7 | 42.9% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Pristine™ Long-Term Hemodialysis Catheter | 0 of 7 |
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 |
|---|---|
| Pristine™ Long-Term Hemodialysis Catheter | 2 of 7 |
Most frequent serious adverse event terms
| Event term | Organ system | Pristine™ Long-Term Hemodialysis Catheter |
|---|---|---|
| Not Device Related-Septic Shock | Infections and infestations | 1 of 7 |
| Device Related-Thrombosis in device | Product Issues | 1 of 7 |
| Device Related-Thrombosis in device | Product Issues | 1 of 7 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Pristine™ Long-Term Hemodialysis Catheter |
|---|---|---|
| Procedural pain | Injury, poisoning and procedural complications | 1 of 7 |
| Dizziness | Nervous system disorders | 1 of 7 |
Serious events with the highest arm-level rate: not device related-septic shock (14.3%), device related-thrombosis in device (14.3%).
The registry’s adverse-event summary is for the Pristine™ Long-Term Hemodialysis Catheter group. It lists 7 participants at risk, 3 affected by serious adverse events, 2 affected by other adverse events, and 0 deaths. These are safety-summary figures, not the primary complication endpoint, which was not analyzed.
The serious adverse-event terms listed are “Not Device Related-Septic Shock” at 14.3% and “Device Related-Thrombosis in device” at 14.3%. The labels preserve the registry’s reported relationship descriptions. The percentages should be read as recorded for those terms; the basis for calculating them, event counts by term, and whether a participant could contribute to multiple terms are not reported in the registry record.
The safety denominator of 7 is distinct from the registry’s enrollment entry of 142. The record does not report why the safety group is smaller, the observation duration for its members, or how completely events were collected. It also warns that reporting may be inaccurate or potentially misrepresentative because source verification and analysis were not performed. These limitations mean the entries are descriptive registry reports, not a complete, verified estimate of event risk.
12. What the Result Does, and Does Not, Mean
The record establishes that a prospective, multi-center, single-arm study of the Pristine™ Long-Term Hemodialysis Catheter was registered, with enrollment listed as 142 and status recorded as terminated. It also defines a primary endpoint: the overall rate of infectious and non-infectious complications requiring revision to maintain patency and improve access performance, assessed at 3 months after the index procedure.
It does not establish the value of that primary endpoint. No participants were followed to the 3-month follow-up, and the primary endpoint analysis was not performed. There is therefore no posted primary rate, comparison with the performance goal, or associated estimate of statistical uncertainty. The absence of an analyzed endpoint is not evidence that the rate was low, high, or equal to the benchmark.
The registry’s adverse-event entries describe reports in a group of 7 at risk, including 3 participants affected by serious adverse events, 2 affected by other adverse events, and 0 deaths. The two listed serious-event terms each have a reported percentage of 14.3%. These observations do not answer the planned primary question and should not be generalized to the full enrollment entry without additional information about participant flow and follow-up.
More broadly, the single-arm design does not provide a randomized comparison with another catheter or care approach. A comparison with a performance goal would address a different question and would require details about the benchmark and analysis that are not reported in the registry record. The registry also warns that the results may be inaccurate or potentially misrepresentative because source verification and analysis were not performed.
Accordingly, the posted information supports a description of the design, endpoint, and limited safety entries, but not a conclusion about the primary endpoint or comparative performance. Additional verified follow-up and a documented analysis would be needed to estimate the planned outcome; those results are not reported in the registry record.
13. Why This Trial Matters Statistically
This study illustrates a basic distinction between enrollment and analyzable endpoint follow-up. The registry lists enrollment as 142, yet states that no participants reached the 3-month follow-up required for the primary endpoint. Without outcome observations at the specified time, the planned rate cannot be estimated from this endpoint, regardless of the enrollment entry.
It also highlights the difference between a benchmark and a control group. A performance goal derived from DOPPS can serve as a reference for a single-arm outcome, but it does not create a concurrent comparison. Interpreting such a comparison requires the benchmark value and a clear account of its derivation, outcome definition, and statistical uncertainty. Those details are not reported in the registry record.
The record’s safety summaries raise a separate issue: denominators matter. The adverse-event group has 7 participants at risk, while the enrollment entry is 142. Without participant flow, observation time, and clear event-counting details, those figures cannot be treated as though they describe the same population or follow-up experience.
Finally, the record states that no source verification or analysis was performed and cautions that reporting may be inaccurate or potentially misrepresentative. This makes transparency about what was actually analyzed especially important. A trial registration can define a question and planned endpoint, but the existence of a registered study does not itself provide an answer. Here, the most important statistical finding is the absence of a primary endpoint analysis, not an estimated effect.
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 principal trial-specific limitation is the absence of follow-up to the planned 3-month endpoint. The registry states that no participants were followed to that assessment and that the primary endpoint analysis was not performed. The primary question therefore has no posted outcome estimate.
The record is marked terminated but does not report the reason for termination or participant flow. Although enrollment is listed as 142, it is not reported in the registry record how many participants received the device, completed other visits, or contributed to the safety summaries. The reported safety group has 7 at risk; how that group was selected is not reported.
The registry also states that no source verification or analysis was performed and warns of possible inaccurate reporting or misrepresentation. This caveat applies to interpretation of the posted information. It is not possible to assess the reliability of outcome ascertainment, the completeness of event reporting, or the consistency of follow-up from the recorded details.
Further limitations include the single-arm design and the lack of a reported performance-goal value or analysis method. The registry does not report the statistical analysis plan, sample-size justification, analysis populations, missing-data handling, multiplicity approach, interim analyses, or stopping rules. The secondary outcomes are listed, but their analysis results and methods are not reported in the registry record.
For safety, event timing, observation duration, the basis of the listed percentages, and potential overlap between affected participants are not reported in the registry record. These gaps prevent a fuller assessment of safety rates or comparison across groups. They also make it important not to interpret the safety counts as a substitute for the unperformed primary endpoint analysis.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: The Pristine Post-Market Study — NCT05228132.
- Registry record last updated 2024-04-11; status last verified 2024-03.
- Results first posted 2024-04-11.
- 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 Pristine Post-Market Study is a prospective, multi-center, single-arm study of the Pristine™ Long-Term Hemodialysis Catheter. The registry lists enrollment as 142, status as terminated, and the primary endpoint timeframe as 3 months after the index procedure. The endpoint combined infectious and non-infectious complications requiring revision to maintain patency and improve access performance, with comparison to a performance goal derived from DOPPS.
No participants were followed to the 3-month assessment, so the primary endpoint analysis was not performed. The record lists 8 outcome measures and 0 analyses. Its adverse-event summary lists 7 participants at risk, 3 affected by serious adverse events, 2 affected by other adverse events, and 0 deaths. The registry cautions that reporting may be inaccurate or potentially misrepresentative because source verification and analysis were not performed.