Prostatic Artery Embolization (PAE) for Treatment of Signs and Symptoms of Benign Prostatic Hyperplasia (BPH) Using Bead Block Microspheres: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Prostatic Artery Embolization (PAE) for Treatment of Signs and Symptoms of Benign Prostatic Hyperplasia (BPH) Using Bead Block Microspheres (NCT03052049), a na na study. The primary outcome is Number of Reported Treatment-related Adverse Events (AE) as Assessed by NCI CTCAE Grading Scale ..

2. Clinical Question

3. Trial Design

This was an open-label, non-randomized feasibility study of prostate artery embolization for signs and symptoms of benign prostatic hyperplasia. It had a single group: patients received PAE. The registry lists the study as completed and reports an enrollment of 28. The study began on 2017-09-06, with primary completion on 2022-09-26.

Because there was no random allocation and no separate control arm, the design is not a treatment-versus-control comparison. The record does not support attributing observed changes to the procedure by comparing them with outcomes in a concurrent untreated or alternative-treatment group. The stated purpose was to evaluate safety, while the registry also lists symptom, quality-of-life, impact-index, and urine-flow outcomes.

The primary endpoint concerns the number of reported treatment-related adverse events, graded using the NCI CTCAE scale over a 1 year timeframe. The description says events were graded at 1, 3, 6, and 12 months after the procedure. Secondary outcomes are changes in the International Prostate Symptom Score, Quality of Life Bother Score, Benign Prostatic Hyperplasia Impact Index Score, and peak urine flow (Qmax).

The registry record does not report the detailed protocol, eligibility criteria, recruitment process, sample-size justification, or a fuller statistical analysis plan. It also does not explain why the safety summary lists 26 participants at risk while enrollment is 28. These omissions limit assessment of who contributed to each analysis and how the study was intended to handle incomplete observations.

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: Events

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Number of Reported Treatment-related Adverse Events (AE) as Assessed by NCI CTCAE Grading Scale ., measured over 1 year.

The primary endpoint is the number of reported treatment-related adverse events assessed using the NCI CTCAE grading scale. It is a count endpoint: the intended quantity is how many events were recorded, rather than a change in a symptom score or a comparison between treatment groups. The registry describes grades from mild (grade 1) through fatal (grade 5), based on the event's impact on daily activities and clinical status, and states that grading was assessed at 1, 3, 6, and 12 months after the procedure.

Safety event counts are used to describe the kinds and burden of adverse events observed during a specified follow-up period. Grading adds information about severity, while the treatment-related designation is intended to distinguish events considered related to the intervention from other events. However, the registry does not report the primary endpoint's event count or grade-specific results. The adverse-event summary lists affected counts for serious and other events, but it does not state that these values are the primary endpoint's treatment-related, CTCAE-graded event count. They should therefore be read as a separate safety summary, not as a substitute for the unreported primary endpoint result.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical methods determine how study observations are turned into estimates and how much uncertainty should accompany those estimates. For this study, the registry provides the endpoint definitions and design description, but does not report a detailed statistical analysis plan or the methods used to produce the posted outcome results. The following concepts explain what would matter when interpreting a single-group safety study; they do not assert that any particular unreported method was used.

What does a single-group design allow?

A single-group study can describe outcomes among participants who received the intervention. If measurements are made before and after treatment, a within-participant change can also be described. But without a comparator group, that change is not an estimate of the difference between PAE and an alternative. It may reflect the procedure, natural history, concurrent care, measurement variation, or other factors. Randomization, when used in a comparative design, helps balance known and unknown influences across groups; this study is listed as non-randomized and single-group.

Open-label means the study was not masked. The registry lists masking as none. In general, awareness of treatment can affect reporting, clinical decisions, and outcome assessment, especially for subjective symptom or quality-of-life measures. The registry does not describe safeguards against such influences or whether outcome assessors were independent.

How should a count endpoint be understood?

The primary endpoint is a number of reported treatment-related adverse events, with severity graded under NCI CTCAE. A count describes event frequency, but its interpretation requires a defined observation period, a rule for recurrent events, and clarity about whether the unit is events or participants experiencing events. The timeframe is 1 year, and assessments are described at 1, 3, 6, and 12 months. The registry does not report how repeated or ongoing events were counted, nor the endpoint's observed total.

Count outcomes can have a skewed distribution: many participants may have few or no events, while a smaller number may have more. If event counts vary more than a simple count model expects, over-dispersion can matter because methods that assume less variability may understate uncertainty. This is a general statistical consideration, not a claim about this study. The registry does not report the model or other method used for the endpoint, so it is not possible to assess whether over-dispersion was evaluated.

What does a confidence interval convey?

In general, a confidence interval describes the precision of an estimate under the assumptions of the method used. A narrow interval indicates greater statistical precision than a wide one, while neither guarantees that the design is free from bias. For a single-group study, an interval around an event rate or a change score would still not supply the missing control-group comparison. The registry record does not report confidence intervals for the listed safety counts or outcome measures.

Why do analysis populations matter?

In general, an analysis population specifies which participants are included in a particular result. The number enrolled can differ from the number analyzed because of non-enrollment in a final analysis, missing measurements, or other reasons. Here, the registry reports enrollment of 28 and an adverse-event summary at-risk count of 26. It does not explain the difference or identify analysis populations for the primary or secondary outcomes. The at-risk count should therefore not be treated as the analysis denominator for every outcome.

What can planning calculations show?

Sample-size calculations are planning tools that describe what a design might be able to detect under stated assumptions. They are not observed results or evidence that a study had a particular probability of finding an effect. Any planning illustration based on an observed effect is especially dependent on that estimated effect and the specified assumptions. The registry record does not report the study's own sample-size justification. The assumptions described for planning illustrations include a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; such two-arm assumptions do not describe this single-group study's actual design.

These distinctions matter because a design, an endpoint definition, and an analysis result answer different questions. The record establishes the intended safety measure and the single-group structure, but does not report the primary endpoint result or the methods needed to evaluate its precision. No inferential conclusion can be drawn from an unreported result.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists one primary safety endpoint and four secondary outcomes: changes in IPSS, QOL Bother Score, BPH Impact Index Score, and Qmax. When several outcomes are examined, the chance of at least one apparently notable result can increase if each is tested separately without adjustment. In general, multiplicity procedures can control that issue, but the appropriate approach depends on the study's objectives and analysis plan.

The registry record does not report whether multiplicity was addressed, how outcomes were prioritized beyond the primary and secondary labels, or whether any analyses were exploratory. It also does not report the statistical tests, models, significance thresholds, or confidence intervals used for the outcomes. The existence of a primary endpoint does not, on its own, establish how secondary analyses were interpreted.

Missing-data methods and analysis populations are also not reported in the registry record. The enrollment is 28, while the adverse-event summary lists 26 at risk. The record does not explain this difference, describe completeness of follow-up, give outcome-specific denominators, or state whether missing observations were imputed, excluded, or handled by another method. It also does not report whether all enrolled participants were included in any analysis. Without those details, readers cannot assess whether outcome summaries represent the full enrolled group or a subset, and cannot determine how missing observations may affect interpretation.

11. 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 0% reporting threshold.

Most frequent non-serious adverse event terms

The registry's adverse-event summary lists the PAE group with 26 participants at risk, 0 serious adverse-event affected participants, 10 other adverse-event affected participants, and 0 deaths. These are descriptive safety counts in the registry summary. The serious-event terms list is empty.

These figures should not be conflated with the primary endpoint result. The primary endpoint is defined as the number of reported treatment-related adverse events graded using NCI CTCAE over a 1 year timeframe. The adverse-event summary does not state that its affected counts are treatment-related, does not provide CTCAE grades, and does not give the endpoint's event total. A count of affected participants also need not equal a count of events if one participant can experience more than one event.

The at-risk count is not the enrollment count, and the registry does not explain the difference. The summary does not provide event-level descriptions for the other adverse events, timing, duration, or attribution. Thus, it is a limited descriptive record rather than a complete account of the endpoint or a comparison against another group.

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

The posted information establishes that this was a completed, open-label, non-randomized, single-group feasibility study of PAE, with a stated focus on safety. The registry lists 28 enrolled participants and reports an adverse-event summary for 26 participants at risk. That summary records 0 serious adverse-event affected participants, 10 with other adverse events, and 0 deaths. These counts describe the registry's listed safety summary and should not be treated as a comparative estimate.

The primary endpoint result is not reported in the registry record. In particular, the record does not give the total number of treatment-related events graded under NCI CTCAE, the distribution of grades, or details needed to reconcile the endpoint definition with the separate adverse-event summary. The four secondary measures are named, but their results are not reported. There is therefore no posted estimate of change in symptom scores, quality of life, BPH impact, or peak urine flow to interpret.

Even if outcome changes were available, a single-group design would not show what would have happened to similar participants without PAE or under another treatment. An observed change after treatment is not equivalent to a causal treatment effect. No randomized control comparison is listed, and no precision estimates are reported for the summary counts.

Accordingly, the record does not establish that PAE caused a particular level of benefit or harm, nor does it establish comparative safety or efficacy. It provides the design, intended endpoints, and selected safety counts, while leaving the main endpoint findings, secondary outcome findings, analysis methods, and important follow-up details unreported. The most defensible reading is limited to those descriptive details and the uncertainty created by the missing results and methods.

13. Why This Trial Matters Statistically

This study is statistically informative as an example of the distinction between feasibility evidence and comparative evidence. A single-group feasibility study can document that participants received an intervention and can collect safety and outcome measures. It can also help identify what should be measured in later work. But it cannot supply the same causal comparison as a design with a suitable control group, because there is no concurrent estimate of outcomes in the absence of the intervention.

The endpoint also illustrates why definitions matter. A total count of treatment-related, graded adverse events is not interchangeable with a summary of participants affected by serious or other adverse events. Event counts and participant counts answer different questions, and attribution and severity grading add further distinctions. Here, the registry states the intended primary endpoint but does not report its result, while separately listing affected counts in a safety summary.

Another statistical lesson is the importance of denominators and analysis populations. Enrollment is listed as 28, but the adverse-event summary lists 26 at risk. Without an explanation or outcome-specific denominators, readers cannot determine which participants contributed to each result. Similarly, naming secondary outcomes does not make their results available; estimates and uncertainty are required to assess their magnitude and precision.

The registry record therefore makes clear both what the study set out to measure and where interpretation is constrained. Its single-group structure, unreported primary and secondary results, and limited information on analysis methods prevent strong conclusions about comparative effects. Those limitations are central to the statistical reading, rather than details that can be repaired by interpreting the safety counts more broadly.

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.

Several limitations specific to this record restrict interpretation. The primary endpoint is defined as treatment-related adverse events graded using NCI CTCAE, but its result is not reported in the registry record. The adverse-event summary gives affected counts without event descriptions or grades, so it cannot fill that gap. The summary reports 26 participants at risk, while enrollment is 28; the reason for this difference and the outcome-specific analysis denominators are not reported.

The registry identifies the design as open-label, non-randomized, and single-group. There is no separate comparator arm, so the study cannot provide a direct comparison with an alternative or estimate outcomes that would have occurred without the intervention. Awareness of treatment may also influence symptom reporting and assessments, and the record does not describe masking of outcome assessors or other steps to limit this possibility.

Although four secondary outcomes are listed, their results, variability, and follow-up details are not reported. The registry also does not report the statistical methods, missing-data procedures, analysis populations, multiplicity approach, or sample-size justification. For the event endpoint, rules for counting recurrent events and handling events across follow-up assessments are not specified. These omissions prevent assessment of precision, completeness, and the consistency between the endpoint definition and the posted safety summary.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Prostatic Artery Embolization (PAE) for Treatment of Signs and Symptoms of Benign Prostatic Hyperplasia (BPH) Using Bead Block Microspheres — NCT03052049.
• Registry record last updated 2023-10-10; status last verified 2023-10.
• Results first posted 2023-04-12.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The registry describes a completed, open-label, non-randomized, single-group feasibility study of prostate artery embolization for lower urinary tract symptoms attributed to BPH. Enrollment was 28. The primary safety endpoint was the number of reported treatment-related adverse events graded using NCI CTCAE over a 1 year timeframe, with assessments described at 1, 3, 6, and 12 months.

The listed adverse-event summary reports 26 participants at risk, 0 serious adverse-event affected participants, 10 with other adverse events, and 0 deaths. The primary endpoint result and results for the four secondary outcomes are not reported in the registry record. The record does not provide a control-group comparison or enough analysis detail to assess precision, missing data, or the reason for the difference between enrollment and the safety at-risk count. Interpretation is therefore limited to the study design and the descriptive safety counts.