Prismaflex HF20 Set and Prismaflex® System 7.10/7.20 for Acute Continuous Renal Replacement Therapy (CRRT) in Children: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Prismaflex HF20 Set and Prismaflex® System 7.10/7.20 for Acute Continuous Renal Replacement Therapy (CRRT) in Children (NCT02561247), a na na study. The primary outcome is Percent Change From Baseline in BUN (mg/dL) at 24 Hours Following Initiation of CRRT.

2. Clinical Question

The study’s stated objective centers on BUN reduction during treatment, rather than a comparison of the device with another treatment. Creatinine, bicarbonate, and HF20 Set filter survival time are listed as secondary outcomes. The arm description also specifies that BUN, creatinine, and bicarbonate were measured at 12 hour intervals during CRRT treatment. These measurements describe the planned clinical observations, but the registry record does not report their numerical results or a detailed analysis plan.

The record lists 23 enrolled participants and a status of terminated. It does not report the reason for termination. Without numerical outcome estimates, details of missing observations, and a comparator group, the record does not establish how much BUN changed during treatment or whether any change can be attributed to the devices.

3. Trial Design

This is a single-group device evaluation in pediatric patients with acute kidney injury. The registry lists Prismaflex HF20 CRRT Filter and Prismaflex System 7.10 and 7.20 as device interventions. Its official title names the HF20 Set and Prismaflex System 7.10, while the broader registry title and intervention listing also mention System 7.20. The registry does not explain the relationship between system versions or whether use differed by participant.

Enrollment is listed as 23. Allocation is NA, and the masking entry is NONE. The record therefore does not describe random assignment or masking. It lists a single arm, Prismaflex HF20 CRRT, rather than a separate control arm. A comparator is not reported in the registry record, so changes observed in this group cannot be contrasted with outcomes under an alternative device or treatment within the study.

The arm description states that participants would receive treatment for a minimum period of 20 of the first 24 hours and up to 72 hours with each Prismaflex HF20 Set. It describes BUN, creatinine, and bicarbonate measurements at 12 hour intervals during CRRT treatment. The primary endpoint is specified at 24 hours following CRRT initiation; this endpoint time point should not be confused with the longer possible treatment period. The registry record does not provide further details about treatment decisions, discontinuation, or how measurements were handled when the intended schedule was not completed.

The listed study start date is 2015-11-10, and the primary completion date is 2018-04-06. The status is TERMINATED. A reason for termination, details of the decision, and any effects of termination on planned enrollment or follow-up are not reported in the registry record. The record lists phase as NA, which is consistent with a device evaluation rather than a drug-phase description, but no further explanation is given.

The primary-outcome population description says that the full analysis set followed the intent-to-treat principle and included any patient who received CRRT on the HF20 Set for any period of time. It also says that 17 participants had evaluable primary-endpoint data, a subset of the full analysis set listed as N=23. These are different analysis-population descriptions: the evaluable subset is not the full analysis set. The registry record does not explain why some full-analysis-set participants did not have evaluable data at the primary time point.

Neither a sample-size justification nor a protocol-based statistical design rationale is reported in the registry record. The listed planning assumptions for separate illustrations—two-sided significance level 0.05, equal allocation between two arms, and a normal approximation—do not describe this single-group study’s allocation. They should not be read as evidence of the trial’s original design or as a justification for its enrollment.

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: The full analysis set (FAS) was based on the intent-to-treat (ITT) principle and includes any patient who received CRRT on the Prismaflex HF20 Set for any period of time. Number of subjects (n=17) with evaluable data is shown, which is a subset of FAS (N=23).

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: The full analysis set (FAS) was based on the intent-to-treat (ITT) principle and includes any patient who received CRRT on the Prismaflex HF20 Set for any period of time.

6. Primary Endpoint

The registry lists the primary outcome as Percent Change From Baseline in BUN (mg/dL) at 24 Hours Following Initiation of CRRT, measured over 24 hours from CRRT initiation.

The primary endpoint is percent change from baseline in BUN, measured in mg/dL, at 24 hours following initiation of CRRT. BUN is a blood measure named in the registry as the primary indicator for evaluating the stated objective: whether the HF20 Set delivers renal replacement therapy that reduces BUN in pediatric patients with acute kidney injury. The endpoint therefore focuses on a laboratory measure at a defined time after treatment begins, rather than on a direct comparison between treatment groups.

Percent change expresses a follow-up measurement relative to a participant’s baseline value. In general, this kind of scale can make the size of a change interpretable in relation to the starting measurement. However, the precise calculation convention used for this endpoint, including how participant-level values were combined and how any missing baseline or follow-up measurements were treated, is not reported in the registry record.

The registry identifies the endpoint parameter as a mean and the dispersion measure as a standard deviation. Those labels describe how the endpoint was intended to be summarized: the mean represents the average observed percent change in the analyzed participants, while the standard deviation describes variation among individual observations. The numerical mean and standard deviation are not reported in the registry record. A confidence interval, test statistic, and p-value for the primary endpoint are also not reported in the registry record.

That absence matters for interpretation. The endpoint definition alone explains what the study intended to measure; it does not establish the size or direction of the observed BUN change. Nor does a change in this laboratory measure by itself establish a broader clinical effect. The registry’s stated rationale connects BUN reduction with renal replacement therapy, but patient-level clinical outcomes and the numerical primary-endpoint findings are not available in the record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies a continuous primary endpoint summarized by a mean and standard deviation. The statistical concepts below are general explanations of these measures and do not imply that every method was used in the study. The registry record does not report a detailed analysis plan or the numerical primary-outcome estimate.

What does the mean describe?

For a continuous outcome such as percent change in BUN, a mean is an average across the observations included in the analysis. It provides a compact description of the typical result in that analyzed group, while retaining the direction of change. For a percent-change endpoint, the mean would summarize the participants’ relative changes from baseline at the stated time point. It would not, by itself, describe how much participants varied or how precisely the average was estimated.

The registry labels the primary parameter as MEAN, but does not provide the mean value. It also does not give a participant-level calculation rule for percent change. In general, percent change requires a baseline and follow-up value, but the exact handling of special cases, missing values, and aggregation is not reported in the registry record. A reader should therefore not infer a precise computation procedure beyond the endpoint’s stated name and time point.

What does the standard deviation describe?

A standard deviation summarizes the spread of individual observations around their mean. A relatively wider spread indicates more variability among observed values; a narrower spread indicates values are more clustered around the average. This is a description of participant-to-participant variation, not a direct measure of the uncertainty in the estimated mean.

Standard deviation and standard error answer different questions. The standard deviation describes variation in the observed data. The standard error describes the sampling uncertainty of an estimate, under assumptions about the data and analysis. A confidence interval uses an estimate and its uncertainty to indicate a range of values compatible with the data under a stated statistical procedure. These are general concepts; the registry does not report a standard error or confidence interval for the primary endpoint, and no such quantity can be reconstructed from the endpoint description alone.

Why does the single-group design matter?

A single-group study can describe outcomes observed among participants receiving the device intervention. It cannot, without an appropriate comparison, directly estimate how those outcomes differ from what would have occurred under another treatment or without the intervention. A baseline-to-follow-up change can be informative descriptively, but it does not by itself control for changes in illness, concurrent care, measurement conditions, or other time-related influences.

Here, allocation is recorded as NA, the model is SINGLE GROUP, and the masking entry is NONE. These registry entries do not describe random assignment, a control arm, or masking. Because the record does not identify a concurrent comparator, there is no treatment contrast from which to estimate a comparative effect. This does not mean that the within-group measurement is meaningless; it means that its interpretation is limited to the observed group and cannot isolate a causal effect of the devices.

How should the analysis population be read?

The primary-outcome description says that the full analysis set was based on the intent-to-treat principle and included any patient who received CRRT on the HF20 Set for any period of time. It separately reports 17 participants with evaluable data as a subset of the full analysis set, listed as N=23. The distinction is important: an analysis using only evaluable observations may not include everyone in the stated full analysis set. The record does not explain the reasons for the difference or describe an imputation or other missing-data procedure.

Missing outcome data can affect both the estimated average and its uncertainty, particularly if the availability of measurements is related to participants’ condition or treatment experience. This is a general concern, not a claim about what happened in this study. Since the registry does not report why outcome data were unavailable or how the analysis addressed them, the potential influence cannot be evaluated.

What about repeated measurements?

The arm description states that BUN, creatinine, and bicarbonate were measured at 12 hour intervals during CRRT treatment. Repeated measurements from the same participant are generally correlated: observations from one person are not necessarily statistically independent of one another. Analyses that use repeated measurements may need to account for this within-participant relationship. The registry does not report whether the primary analysis used only the 24-hour endpoint, incorporated the repeated measurements, or used a model for correlated observations. The endpoint is specified at 24 hours, but that does not establish the complete analytical approach.

For continuous measurements, distributional features can also matter. An average can be influenced by unusually high or low values, and an analysis based on a normal approximation may be less suitable when data are strongly skewed or contain influential observations. These are general considerations; the registry does not report distribution checks, transformations, robust methods, or diagnostic procedures for the outcome.

What can be inferred from the planning assumptions?

The registry lists assumptions for planning illustrations: a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It also describes the illustrations as based on an observed effect and distinguishes participants per arm from total events for time-to-event calculations. These are assumptions for illustrative planning, not a description of the actual single-group allocation. The numerical illustration results are not reported in the registry record, and the stated assumptions do not establish the study’s original sample-size justification.

Power is a design concept concerning the chance that a planned test will detect an effect of a specified size under stated assumptions. It is not a measure of how convincing an observed result is after data collection. A planning illustration based on an observed effect should not be treated as observed power or as proof that the study was adequately sized. The registry does not report a protocol-based sample-size rationale, a prespecified effect target, or the numerical outputs of the illustrations.

10. Confidence Intervals for Each Arm

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

R code and output

arm <- c("Prismaflex HF20 CRRT")
n   <- c(17)
m   <- c(-58.118)
sp  <- c(20.0848)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Prismaflex HF20 CRRT  17  -58.118  20.085  -68.445  -47.791

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary BUN outcome and secondary outcomes covering percent change from baseline in creatinine and bicarbonate at 24 hours following CRRT initiation, as well as HF20 Set filter survival time. It reports five outcome measures and one analysis. Those registry counts do not, on their own, explain how many statistical tests were performed, how outcomes were prioritized in analysis, or whether any adjustment was used for multiple testing. A multiplicity plan is not reported in the registry record.

Multiplicity matters when several outcomes, time points, or analyses are examined. In general, the more statistical tests considered, the greater the opportunity for a result to appear notable by chance if each test is judged separately. Methods for addressing this issue can include prespecifying a primary outcome, adjusting significance thresholds, or treating secondary findings as exploratory. The record identifies a primary endpoint and secondary outcomes, but does not describe a testing hierarchy or adjustment procedure. It is not possible to conclude from the count of analyses alone that multiplicity was either controlled or irrelevant.

The registry gives a limited account of the analysis population. The full analysis set is described as following the intent-to-treat principle and including any patient who received CRRT on the HF20 Set for any period of time. The primary endpoint has evaluable data for 17 participants, identified as a subset of the full analysis set listed as N=23. Reasons for unavailable primary-endpoint data, missing-data handling, and the number of participants contributing to secondary outcomes are not reported in the registry record.

Missing data can influence estimated outcomes when participants without measurements differ from participants with measurements. General approaches include analyzing available observations, using a model that accommodates incomplete repeated measurements, or applying an imputation method. The appropriateness of any approach depends on the data and assumptions. The registry does not identify the method used, so no particular missing-data procedure should be attributed to this study.

The record does not report a prespecified statistical analysis plan, the timing of any analyses, or interim-analysis procedures. It also does not explain how study termination affected the analysis population or the availability of outcome data. These omissions limit assessment of the analysis decisions and of the robustness of any result; they do not establish that a particular procedure was or was not used.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: cardiac arrest (4.3%), right ventricular failure (4.3%), hypercalcaemia (4.3%), intraventricular haemorrhage (4.3%), pleural effusion (4.3%).

The registry lists safety counts for the Prismaflex HF20 CRRT group. Serious adverse events are reported for 5 participants at risk of 23. Other adverse events are reported for 16 participants at risk of 23, and deaths are listed as 2. These are separate registry entries; the record does not explain whether there was overlap among participants or events, so the counts should not be added together.

The listed serious-event terms are Cardiac Arrest, Right Ventricular Failure, Hypercalcaemia, Intraventricular Haemorrhage, Pleural Effusion, and Pulmonary Haemorrhage. Each term is reported at 4.3%. The registry does not provide event-level counts alongside those percentages, describe whether participants could contribute more than one term, or report timing and duration in this summary. The percentages should therefore be read as the registry’s reported figures, without attempting to reconstruct their denominators or infer how events were distributed across participants.

An adverse event recorded during a study is not automatically an event caused by the device or treatment. Establishing attribution requires information about timing, clinical assessment, and the study’s relatedness criteria. Those details are not reported in the registry record. The single-group design also offers no control-arm safety rate for comparison. The figures describe what was recorded in the study group; they do not establish a comparative risk or prove causation.

The status is TERMINATED, but the reason for termination and its relationship, if any, to safety findings are not reported in the registry record. The safety counts should be interpreted without assuming a reason for study termination.

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

The record defines a study intended to evaluate the Prismaflex HF20 Set for acute CRRT in children with acute kidney injury. Its primary endpoint is percent change from baseline in BUN at 24 hours following CRRT initiation, and the registry identifies the mean and standard deviation as the intended summary statistics. However, the numerical result for this primary endpoint is not reported in the registry record. The record therefore does not establish whether BUN increased or decreased, how large any change was, or how precisely it was estimated.

The trial design also sets clear boundaries on interpretation. It is a single-group evaluation, with allocation recorded as NA and no comparator arm listed. Even if a before-and-after change were available, a within-group observation alone could not separate a device-associated effect from the course of illness, other care, or other influences. The registry does not report a comparative estimate.

The full analysis set is described as including any patient who received CRRT on the HF20 Set for any period of time. The primary-outcome description reports 17 evaluable participants as a subset of the full analysis set listed as N=23. The reasons for unavailable outcome data and the methods used to address them are not reported in the registry record. This makes it difficult to assess how representative the evaluable observations are of the full analysis set.

The safety entries report serious adverse events for 5 participants at risk of 23, other adverse events for 16 at risk of 23, and 2 deaths. Serious-event terms are listed at 4.3% each. These figures are descriptive and do not establish that the devices caused the events. No control-group rates are reported, and event attribution details are not reported in the registry record.

The study status is TERMINATED, with a reason not reported in the registry record. The status alone does not explain whether or how termination affected the planned study procedures or available data. Likewise, the registry’s planning assumptions do not provide a protocol-based sample-size justification or establish observed power. In short, the record conveys the research question, basic design, analysis-population description, and some safety counts, but it does not supply the numerical primary result needed to assess the observed BUN outcome.

14. Why This Trial Matters Statistically

This study illustrates how a clearly stated clinical endpoint and a limited design can lead to different kinds of statistical information. The primary question is focused: assess percent change from baseline in BUN at 24 hours following CRRT initiation. The record also specifies a mean and standard deviation, so it identifies the intended summary and measure of spread. But without the numerical estimate, those definitions cannot tell a reader what change was observed or how variable participant outcomes were.

The study also highlights why the analysis population must be read alongside an endpoint. The full analysis set is described as based on the intent-to-treat principle, while 17 participants with evaluable primary-endpoint data are reported as a subset of the full analysis set listed as N=23. A reader needs both pieces of information to understand which population the endpoint description concerns. The registry does not report the reasons for the difference or the missing-data approach, leaving uncertainty about how the evaluable observations relate to the broader analysis set.

Design is equally important. A single-group device evaluation can describe measurements collected during treatment, but it does not provide a concurrent contrast with another approach. This distinction is central to interpreting any within-group change: description and causal comparison are not the same statistical task. The record’s allocation and masking entries reinforce that no randomized, masked comparison is described.

Finally, the safety counts show why event totals require context. Serious adverse events, other adverse events, deaths, and event terms are reported, but these figures do not establish attribution or comparative risk. A registry record is most informative when outcome estimates, uncertainty, analysis populations, missing-data methods, and safety definitions can be considered together. In this case, several of those details are not reported, so the sound statistical conclusion is bounded by the information available.

15. Limitations

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

The primary limitation for interpreting efficacy is the absence of the numerical BUN result. The registry defines the endpoint and the intended summary statistics but does not report the mean percent change, standard deviation, confidence interval, or p-value. Without an estimate and measure of uncertainty, the direction, magnitude, and precision of the primary finding cannot be assessed from the registry record.

The single-group design limits comparative interpretation. No control arm is described, and allocation is listed as NA. Any within-group change would not, on its own, distinguish the contribution of the device from the natural course of acute kidney injury, concurrent care, or other factors. Masking is listed as NONE, and the record does not report further procedures to reduce measurement or assessment bias.

The primary-outcome description identifies 17 evaluable participants as a subset of the full analysis set listed as N=23, but does not report why data were unavailable or how missing measurements were handled. This limits assessment of potential selection or missing-data bias. The registry also does not report the detailed statistical analysis plan, the treatment of repeated observations, or the calculation convention for percent change.

The record lists five outcome measures and one analysis, but does not report a multiplicity strategy or clarify how secondary outcomes were handled inferentially. It does not provide numerical results for the secondary outcomes or filter survival time. The stated planning assumptions do not supply a sample-size justification for the actual single-group design, and numerical planning outputs are not reported in the registry record.

Finally, study status is TERMINATED, while the reason for termination and its consequences for enrollment, follow-up, or analysis are not reported in the registry record. Safety counts are descriptive and lack a comparator and event-attribution details. Together, these limitations constrain both efficacy and safety interpretation without establishing what the unreported analyses or data would show.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Prismaflex HF20 Set and Prismaflex® System 7.10/7.20 for Acute Continuous Renal Replacement Therapy (CRRT) in Children — NCT02561247.
• Registry record last updated 2025-07-14; status last verified 2025-07.
• Results first posted 2021-06-16.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

19. Record Summary

The registry describes a single-group device evaluation in pediatric patients with acute kidney injury receiving acute CRRT. The interventions are the Prismaflex HF20 CRRT Filter and Prismaflex System 7.10 and 7.20. Enrollment is 23; allocation is NA; masking is NONE; and the study status is TERMINATED. The listed start date is 2015-11-10, and the primary completion date is 2018-04-06.

The primary endpoint is percent change from baseline in BUN at 24 hours following CRRT initiation, summarized as a mean with standard deviation. The full analysis set is described as including any patient who received CRRT on the HF20 Set for any period of time; 17 participants are identified as having evaluable endpoint data, a subset of the full analysis set listed as N=23. The numerical primary result and reasons for unavailable data are not reported in the registry record.

Safety entries list serious adverse events for 5 participants at risk of 23, other adverse events for 16 at risk of 23, and 2 deaths. Six serious-event terms are each listed at 4.3%. The reason for termination, comparative safety data, and event-attribution details are not reported in the registry record.