CaveoVasc System - a New Femoral Vascular Access and Closure Device: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for CaveoVasc System - a New Femoral Vascular Access and Closure Device (NCT02694549), a na na study. The primary outcome is Incidence at 30 Days After the Procedure of the Composite Endpoint of Access Site Related Major Adverse Vascular Events (MAVE)..

2. Clinical Question

3. Trial Design

This was a prospective, single-arm study of the CaveoVasc system. The registry lists the study as nonrandomized, with allocation marked not applicable, and gives an enrollment of 12. Its stated purpose was to assess device performance and safety for femoral vascular access and to prevent bleeding from the femoral artery puncture site. No control intervention or alternative treatment arm is described.

The listed condition is catheterization via a femoral sheath ≤6Fr. The intervention is identified as a device, named CaveoVasc. The arm description is blank, and the registry does not report additional details about how the device was used, the procedure, participant eligibility, or the clinical setting. These omissions limit assessment of how closely a reader could reproduce the study or determine to whom its results might apply.

The study start date is 2016-08-09, and the primary completion date is 2016-10-10. Its status is terminated. The record does not explain why it was terminated or whether termination affected recruitment, follow-up, or outcome collection. The primary endpoint is a 30-day composite of access-site-related major adverse vascular events, measured as a participant count. A secondary safety endpoint is also listed, but its definition and results are not reported in the registry record.

With no control group, the design can describe observations among participants treated with CaveoVasc, but it cannot estimate a comparative effect against another device or approach. The enrollment figure is a registry design detail, not evidence that all intended participants completed follow-up or contributed to every outcome. The relation between enrollment and the smaller denominators appearing in the safety record is not explained.

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:

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 Incidence at 30 Days After the Procedure of the Composite Endpoint of Access Site Related Major Adverse Vascular Events (MAVE)., measured over 30 days.

The primary endpoint is the incidence at 30 days after the procedure of a composite endpoint of access-site-related major adverse vascular events. The registry specifies the unit as participants and the measure as a count of participants. A composite endpoint combines multiple qualifying events into a single outcome, which can capture a broader range of clinically important complications than an individual event alone. That is a general rationale for composite outcomes; the registry does not specify which events make up this composite or how they were adjudicated.

Focusing on the access site matches the stated purpose of evaluating a device used for femoral vascular access and closure. A defined follow-up timeframe also identifies the period in which the primary endpoint is assessed. These features clarify the intended question, but they do not establish what was observed. The primary result, including the count of participants meeting the composite endpoint, is not reported in the registry record.

Without component definitions and component-level results, a reader cannot tell whether the composite represents a consistent clinical pattern or which event types contributed. Without a reported denominator for the primary endpoint, the count cannot be interpreted as an incidence proportion. The registry record also does not report an analysis method, confidence interval, or other measure of uncertainty for this endpoint.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The methods information in the registry is limited. It identifies a prospective, single-group study, a participant-count primary endpoint, a 30-day timeframe, and zero analyses. It does not report the statistical methods used to evaluate the primary endpoint or the listed secondary safety endpoint. The explanations below describe general statistical concepts relevant to this type of study; they are not claims about methods used by the investigators.

What does a participant count represent?

A count records how many participants meet a specified outcome definition. For the primary endpoint, the registry labels the measure as a count of participants. A count alone does not express the frequency of the outcome unless its denominator is also known. A proportion relates the count meeting an outcome to the number of participants assessed for that outcome. Because the primary endpoint result and its denominator are not reported in the registry record, neither a count nor an incidence proportion can be interpreted from the record.

Even when a numerator and denominator are available, the endpoint definition matters. A composite outcome counts participants who meet one or more qualifying component criteria, but interpretation depends on which components qualify and how they are ascertained. If components vary in importance or frequency, the overall composite can conceal that variation. Component definitions and component-level results are not reported for this endpoint, so its composition cannot be evaluated.

Why does the single-group design matter?

A single-group study observes outcomes in participants receiving the study intervention without a concurrent comparator arm. This can describe events and procedural performance in the observed group. It cannot isolate the effect of the device from other influences, such as participant characteristics, procedural factors, or how outcomes are detected. Those are general design considerations, not findings about this study. The registry does not report a comparison with another device or an alternative approach.

Random allocation, when used in a comparative study, can help balance measured and unmeasured factors across groups on average. Here allocation is listed as not applicable because the study is single-group. There is consequently no randomized contrast to interpret. Even a precisely measured event frequency in this group would not by itself show that the device caused that frequency or that it differs from the frequency under another approach.

What can uncertainty measures add?

In general, a confidence interval describes a range of values compatible with an estimate under a specified statistical model and sampling assumptions. It communicates uncertainty about an estimate; it does not guarantee that the true value lies within the interval or address biases in design and measurement. The registry record does not report a confidence interval for the primary endpoint, nor does it report an estimate from which one could interpret such an interval.

A statistical test can assess compatibility between data and a specified null hypothesis under its assumptions. A p-value does not measure the size or clinical importance of an effect, and a nonsignificant result does not establish equivalence. No p-value or statistical test is reported for the primary endpoint. Therefore, no hypothesis-testing conclusion can be drawn from the registry record.

How should planning calculations be understood?

In general, a sample-size calculation is a planning exercise based on assumptions about an outcome, a target effect, a significance level, power, allocation, and an analysis method. Its output is not an observed result. Planning illustrations based on an observed effect can also be sensitive to how that effect was estimated, particularly when the study is small or the event is uncommon. They cannot replace an analysis of observed outcomes.

The registry record describes planning assumptions for an illustration: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. It also distinguishes planning outputs for time-to-event outcomes from those for other outcomes. These are assumptions described for the planning illustration, not evidence that the trial itself used a two-arm design; the registered study is single-group. No resulting planning estimates or primary observed effect are reported in the registry record, so no sample-size output can be interpreted as a trial finding.

Why can event data require special care?

For binary outcomes, each participant is classified according to whether a defined event occurred during the assessment period. This simple structure still requires clear rules for the analysis population, outcome ascertainment, and missing follow-up. If a participant's outcome is unknown, the handling rule can affect the denominator and estimate. The registry does not report these rules for the primary endpoint. It also does not report whether any primary outcome observations were missing.

When events are clustered, repeated, or arise at unequal rates across participants, a model that assumes a simple common event rate may not reflect the data well. Over-dispersion is a general term for variability greater than a model expects; accounting for it can affect uncertainty estimates. The registry identifies the primary outcome as a participant count, but does not provide enough detail to determine whether event counts, repeated events, or over-dispersion were relevant to the analysis. No model specification is reported.

For safety data, the distinction between participants affected and events recorded is important. One participant could, in general, experience more than one event, so event terms and affected-participant counts are not automatically interchangeable. The registry gives affected-participant figures and lists serious-event terms with percentages, but does not report their denominator or counting convention. Those terms therefore cannot be interpreted as event counts or mapped to participant-level outcomes.

Because no analysis is listed, readers cannot assess whether estimates were adjusted, how the endpoint was analyzed, or whether any sensitivity analyses were performed. Such methods are not presumed to have been used. The central statistical limitation is not a choice among competing models but the absence of a reported primary result and analysis in the registry record.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("CaveoVasc")
n      <- c(10)
events <- c(2)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  CaveoVasc  10  2  20.0  2.5  55.6  5.7  51.0  6.0  51.8

11. Multiplicity, Missing Data and Analysis Populations

The registry lists a primary endpoint and a secondary safety endpoint, and records three outcome measures. It reports zero analyses. It does not state how the multiple outcomes were prioritized beyond identifying the primary endpoint, whether any adjustment for multiple testing was planned, or whether secondary outcomes were intended to be descriptive. These details are not reported in the registry record.

In general, testing multiple outcomes can increase the chance of observing an apparently notable result by chance if each test is interpreted separately. Approaches to multiplicity can include prespecifying a hierarchy, adjusting significance thresholds, or treating secondary findings as exploratory. Which approach is suitable depends on the study aims and analysis plan. No multiplicity approach is reported, and there are no reported analysis results to evaluate under such an approach.

The record does not report a primary endpoint denominator or missing-data rules. It also does not report whether all enrolled participants completed the 30-day assessment, how incomplete follow-up was handled, or whether any participants were excluded from analysis. The safety record's at-risk denominators are 10, while enrollment is 12; the reason for that difference is not reported. It would be inappropriate to infer from those figures alone that a particular number of participants lacked follow-up or were excluded.

The analysis population is not described for either primary or secondary outcomes. The record does not specify whether analyses were based on all enrolled participants, those who received the device, those with outcome data, or another defined population. This limits assessment of selection and of how the reported safety denominators relate to the intended study population. Since no analyses are reported, neither missing-data handling nor multiplicity can be checked against actual estimates.

12. Safety Results

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

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: device deficiency : closure issue (60.0%), device deficiency : access issue (30.0%), high blood pressure (10.0%).

The adverse-event record gives 10 participants at risk for serious adverse events and 10 affected. For other adverse events, it gives 10 at risk and 7 affected. These are the figures recorded for the CaveoVasc group. They should be read as separate entries in the registry rather than combined into a single total; the record does not explain whether the groups of affected participants overlap or how repeated events were counted.

The leading serious-event terms are listed as “Device Deficiency : closure issue” at 60.0%, “Device deficiency : Access issue” at 30.0%, and “High Blood Pressure” at 10.0%. The registry does not report the denominator or counting convention behind these percentages. They therefore cannot be translated into participant counts, treated as percentages of all enrolled participants, or used to infer event frequency without additional information.

The deaths entry is not reported in the registry record. The adverse-event entries do not give event dates, severity details beyond the serious-event classification, causal assessments, or the relationship of each term to the primary composite. They also do not establish whether a listed event was caused by the device. These safety figures describe what the registry records, not a comparative risk estimate. No control group or adjusted safety analysis is reported.

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

The record supports a limited description of a prospective, single-group study of CaveoVasc, its stated purpose, and its intended primary endpoint. It also includes selected safety figures for participants listed as at risk. Those details can help readers understand what the study set out to assess and what safety information was entered in the registry.

The record does not report the primary composite endpoint result. It therefore cannot establish the observed frequency of access-site-related major adverse vascular events at 30 days. It does not report an analysis, an estimate of uncertainty, or a comparative result. The registry’s enrollment figure should not be treated as the primary endpoint denominator, because the endpoint population is not specified.

Because the study has a single group and no comparator, its design cannot provide a direct estimate of how outcomes would differ under another device or approach. Even if the registry reported a complete outcome count, a single-group observation would not alone demonstrate that the intervention caused the observed outcome pattern. The record does not report a causal analysis or external comparison.

The safety entries are not a substitute for the missing primary result. Their denominators, event-term percentage basis, and relation to the endpoint are not fully described. The fact that the registry lists affected participants does not establish the cause, timing, or clinical interpretation of each event. The death entry is not reported in the registry record.

Accordingly, the result does not establish efficacy, comparative safety, or the absence of complications. It also does not show that no primary endpoint events occurred: the primary outcome result is simply not reported. Interpretation should distinguish the stated study objective and recorded safety entries from evidence that would require defined, complete outcome data and a reported analysis.

14. Why This Trial Matters Statistically

This study is statistically informative as an example of how a clear clinical question and an interpretable result are different things. The registry defines a relevant target: a 30-day composite of access-site-related major adverse vascular events, measured as a participant count. Yet it does not report the endpoint result or an analysis. Without those, the central quantity the study aimed to assess cannot be evaluated from the registry record.

The single-group design also illustrates the distinction between describing outcomes and estimating comparative effects. A study can record what happens among participants receiving a device, but a control group is needed for a direct within-study comparison. Even with a comparator, design and analysis assumptions matter; without one, causal and comparative claims are especially limited. The record’s nonrandomized, single-group structure should shape any interpretation of its aims and safety observations.

The differing enrollment and safety denominators underline why population definitions matter. Enrollment is listed as 12, while the safety entries use 10 at risk. Since the relationship between those figures is not reported, readers cannot determine which participants contributed to each outcome or why denominators differ. Clear reporting of analysis populations and follow-up is essential for interpreting both counts and rates.

Finally, the record distinguishes intended outcomes from analyzed findings. It identifies a primary endpoint and secondary safety endpoint, but reports zero analyses. Statistical conclusions require more than an endpoint label: they depend on outcome definitions, denominators, missing-data handling, analytic methods, and uncertainty estimates. This record shows why those reporting elements are necessary to judge what a trial’s data can establish.

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.

Several limitations specific to this study can be identified from the registry record. Its status is terminated, but the reason for termination is not reported. The record does not explain whether termination altered recruitment, follow-up, or completion of planned outcome collection. Enrollment is listed as 12, but the relation between enrollment and the safety denominators of 10 is not explained.

The study has a single group and no comparator, limiting interpretation to observations rather than direct comparisons. The registry does not report participant characteristics, detailed eligibility criteria, procedural setting, device-use protocol, or the arm description. These omissions restrict assessment of the study population, implementation, and generalizability.

The primary endpoint is named as a 30-day composite, but its component definitions and adjudication process are not reported. The primary outcome count, denominator, analysis population, and uncertainty estimate are also absent. Although a secondary safety endpoint and three outcome measures are listed, their definitions and results are not reported. The registry records zero analyses.

The safety information has its own interpretive limits. The percentages accompanying serious-event terms have no reported denominator or counting convention. The record does not describe the relationship between those terms and the affected-participant count, nor does it report causal assessment. The deaths entry is not reported in the registry record.

Finally, no reason for the difference between the enrollment figure and safety denominators can be inferred, and the record does not specify missing-data procedures or analysis populations. These reporting gaps prevent assessment of outcome completeness and the statistical precision of the intended primary result.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: CaveoVasc System - a New Femoral Vascular Access and Closure Device — NCT02694549.
• Registry record last updated 2018-08-28; status last verified 2018-08.
• Results first posted 2018-08-28.
• 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

NCT02694549 is a prospective, single-group study of the CaveoVasc femoral vascular access and closure device. The registry lists enrollment of 12, a study start date of 2016-08-09, a primary completion date of 2016-10-10, and status as terminated. The stated aim was to assess device performance and safety, including prevention of bleeding from the femoral artery puncture site.

The primary endpoint is a 30-day composite of access-site-related major adverse vascular events, measured as a participant count. A secondary safety endpoint is listed. The registry reports zero analyses and does not report the primary endpoint result, its denominator, or a statistical analysis. Safety entries list 10 affected among 10 at risk for serious events and 7 affected among 10 at risk for other events; the basis for the serious-event term percentages is not reported. The single-group design provides no concurrent comparator, and the record does not explain the difference between enrollment and the safety denominators.