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 A Retrospective Study Evaluating the Use of the SoloPath® Sheath in Reducing Vascular and Bleeding Complications (NCT02297308), a registered phase not stated study. The primary outcome is Vascular Access Site Complications.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02297308 |
| Phase | Phase not stated |
| Condition | Vascular Access Complication |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 90 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Terumo Medical Corporation |
| Results posted | Yes |
2. Clinical Question
Population
People who underwent transcatheter aortic valve implantation (TAVI) with femoral vascular access using a SoloPath® sheath. The registry record lists enrollment as 90, but detailed eligibility criteria and the number included in the primary outcome analysis are not reported in the registry record.
Intervention
Use of the SoloPath® Balloon Expandable TransFemoral Introducer for femoral vascular access during TAVI. The record describes data collection focused on subjects who underwent TAVI with this sheath.
Comparator
A comparator group is not reported in the registry record. The record describes a retrospective, single-center collection focused on SoloPath sheath use, and allocation is not stated. It is therefore not a like-for-like controlled comparison.
Primary question
What number of participants had VARC-2 defined vascular access site complications within 30 days of the TAVI procedure when the SoloPath® sheath was used? The registry record gives the outcome definition and timeframe, but not the observed number or an analysis of that outcome.
The clinical question is descriptive rather than a documented comparison of two access strategies. The study summary says it assesses bleeding and vascular complications associated with TAVI when the SoloPath® introducer is used for access. A secondary outcome concerns bleeding complications at the access site. However, the registry record does not report outcome counts, rates, estimates of uncertainty, or statistical tests for either outcome.
General: an observed complication count can describe what happened in a study group, but by itself it cannot establish what would have happened under another access strategy. A comparative conclusion requires an appropriate comparison and an analysis that addresses differences between groups. Neither a comparator nor such an analysis is reported in the registry record.
3. Trial Design
The registry record describes a retrospective, single-center data collection concerning TAVI procedures in which a SoloPath® sheath was used for femoral vascular access. Its brief summary says the study assesses bleeding and vascular complications associated with that use. The record lists enrollment as 90 and gives the study status as completed.
The study start is listed as 2014-10 and primary completion as 2015-03. The record identifies the sponsor as Terumo Medical Corporation. These registry entries describe the study record; they do not establish how many participants had data available for each outcome or how many were included in any analysis.
The recorded arm is SoloPath Sheath, described as subjects who underwent TAVI with the sheath used for femoral access. Allocation is not stated. A separate control arm or comparator is not reported in the registry record. The study therefore does not provide a documented randomized or like-for-like comparison between access approaches.
The primary outcome is titled “Vascular Access Site Complications.” It is described as the number of participants with VARC-2 defined vascular complications within 30 days of TAVI. The secondary outcome is bleeding complications at the access site. The record lists two outcome measures, but the outcome values are not reported in the registry record.
Retrospective studies use information collected about events that have already occurred. General: this design can describe the experience recorded in a particular clinical setting, while interpretation depends on how participants were selected, how outcomes were documented, and whether relevant information is complete. Those procedural details, eligibility criteria, and the analysis population are not reported in the registry record. The record also lists no analyses. It does not state a prospective statistical analysis plan, sample-size justification, or interim analyses.
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 | SoloPath Sheath |
|---|---|
| STARTED | 90 |
| COMPLETED | 90 |
| NOT COMPLETED | 0 |
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 | SoloPath Sheath |
|---|---|---|
| Participants analysed | 90 | |
| Age, Continuous | years | 83.3 (SD 6.9) |
| Sex: Female, Male: Female | Participants | 46 |
| Sex: Female, Male: Male | Participants | 44 |
| Region of Enrollment: Canada | participants | 90 |
6. Primary Endpoint
The registry lists the primary outcome as Vascular Access Site Complications, measured over withn 30 days of TAVI procedure.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with a VARC-2 defined vascular access site complication within 30 days of the TAVI procedure. The registry record describes the outcome unit as participants and the parameter as a number. Although the outcome description uses the word “rate,” no rate, denominator, or observed count is reported in the registry record.
General: a clearly defined endpoint makes explicit what event is counted and the period in which it is assessed. A time window matters because events outside that window do not meet the stated endpoint definition. A standardized definition such as VARC-2 can also support consistent classification, although the registry record does not describe how endpoint events were identified or adjudicated in this study.
For a binary participant-level outcome, each participant is classified according to whether the event occurred during the specified period. A count describes the number classified with the event; a proportion additionally needs an appropriate denominator. Neither can be reconstructed from enrollment alone, because the enrollment listing does not establish the number with outcome data or the number analyzed.
Vascular access complications are relevant to the stated study question because the record focuses on femoral access with the SoloPath® sheath. The secondary outcome, bleeding complications at the access site, addresses another complication category named in the study summary. The registry record does not report results for either endpoint, so their observed frequency and precision cannot be assessed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the intended descriptive question: vascular complications after TAVI with femoral access using the SoloPath® sheath, assessed within 30 days. It also identifies access-site bleeding as a secondary outcome. It does not report the observed count for the primary endpoint, a denominator, an effect estimate, a confidence interval, or a statistical test. Consequently, the posted results do not support a quantitative statement about the frequency or precision of complications.
The enrollment listing is 90. That figure is not an outcome denominator: the registry record does not state whether every enrolled participant underwent the procedure, had complete follow-up, or contributed to each outcome analysis. It would therefore be inappropriate to derive an event proportion from enrollment or to assume that the enrollment figure is the analysis population.
The study is described as retrospective and single-center, and the recorded arm focuses on SoloPath sheath use. Allocation is not stated, and a comparator is not reported in the registry record. Thus, no relative effect against another access strategy can be interpreted from the record. Even if a count were available, a single-group description would not by itself estimate what would have occurred under a different approach.
General: precision concerns how much uncertainty surrounds an estimate. For an event proportion, that uncertainty depends on the event count and the number of participants with evaluable outcome data. Confidence intervals express a range of values compatible with the data and the method used, rather than guaranteeing that the true value lies in that range. Since the record reports no outcome estimate or interval, precision cannot be evaluated.
The registry marks the study as completed and lists two outcome measures, while recording no analyses. Completion status does not substitute for reported results. Nor does the absence of a listed analysis establish that no analysis was ever performed outside the registry; it means that an analysis is not reported in the registry record.
The posted information should therefore be read as a description of the study question and design, not as evidence of an observed complication rate or comparative effect. The registry record does not report the primary outcome result, secondary outcome result, missing-data handling, analysis population, or uncertainty estimates. Without those elements, readers cannot judge the magnitude of the observed experience, its precision, or how representative the recorded participants may be.
9. Statistical Methods Explained
The registry record identifies a retrospective, single-center data collection, one recorded SoloPath Sheath arm, a participant-count endpoint, and no listed analyses. The methods discussion below separates those recorded details from general statistical concepts; it cannot fill in methods that are not reported in the registry record.
What does a participant count represent?
The primary outcome is defined as the number of participants with a VARC-2 defined vascular complication within 30 days of TAVI. This is a binary participant-level outcome: a participant either meets the event definition during the stated period or does not. The registry record specifies the unit as participants and the parameter as a number. It does not provide the actual count.
General: a count is not the same quantity as a rate or proportion. A proportion requires a numerator—the participants meeting the event definition—and a denominator—the participants assessed for the outcome. A count without a denominator can describe how many events were recorded but does not establish how common the event was in the group. The enrollment listing of 90 does not establish the denominator for this endpoint.
Why does the outcome definition matter?
The record names VARC-2 as the definition for vascular complications and sets a timeframe within 30 days of the procedure. General: a standard definition can make outcome classification more reproducible, while a fixed follow-up window clarifies which events contribute to the endpoint. The registry record does not state how the definition was operationalized in chart review, who classified events, whether classification was blinded, or how disagreements were handled. Those details are not reported in the registry record.
The outcome description uses the term “rate,” but the stated parameter is a participant number. Without an observed count and denominator, it is not possible to determine whether the posted endpoint was ultimately expressed as a count, a proportion, or another summary. No result should be inferred from the wording alone.
What can a retrospective design establish?
General: retrospective data collection examines records concerning events that have already taken place. It can describe documented outcomes in a defined setting, but the information available may depend on routine documentation and record completeness. If participation or outcome recording is related to clinical characteristics, the resulting description may not represent everyone who underwent the procedure. The registry record does not report the inclusion process, data completeness, or how missing records were handled.
A retrospective single-group description is also different from a controlled comparison. General: a comparison of outcomes between groups can be affected by differences in patient characteristics, clinical decisions, and follow-up. Random allocation, when used, is one approach to reducing systematic differences at baseline, but allocation is not stated for this study and no comparator is reported in the registry record. No adjustment strategy is reported either.
What does uncertainty add?
General: a point estimate alone does not show its precision. A confidence interval communicates sampling uncertainty under the assumptions of its statistical method. For a binary endpoint, methods commonly use the observed event count and evaluable denominator; methods may differ, particularly when events are uncommon or data are sparse. No confidence interval or event estimate appears in the registry record, so neither magnitude nor precision can be assessed.
Over-dispersion is a general issue for some count outcomes: observed variation may exceed what a simple model assumes, which can make model-based uncertainty too narrow if that variation is ignored. This endpoint is described as participants with an event, rather than a repeated-event count or a rate over person-time. The registry record does not state that a count model was used, and no analysis is listed, so over-dispersion should not be presumed to have been relevant to a performed analysis.
How should planning illustrations be read?
The study record contains general planning assumptions describing an illustration based on an observed effect, a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that such illustrations are not the trial’s own design. They are not evidence that this retrospective single-arm record was planned as a two-arm trial. The record does not report a sample-size justification or an actual statistical analysis plan.
General: a planning sample size describes a hypothetical design under stated assumptions. It is not an observed result and is not “observed power.” A planning calculation based on an observed effect is also not independent confirmation of that effect. Since no outcome effect or analysis result is reported in the registry record, no specific planning illustration can be interpreted as evidence about the clinical outcome.
The record lists no analyses. Details such as the statistical test, covariate adjustment, confidence-interval method, missing-data strategy, and analysis population are not reported in the registry record. Any interpretation of those choices would therefore be speculation.
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.
| Arm | Participants | Events | Observed % | Clopper-Pearson 95% CI | Wilson 95% CI | Bayesian 95% credible interval |
|---|---|---|---|---|---|---|
| SoloPath Sheath | 90 | 17 | 18.9% | 11.4% to 28.5% | 12.1% to 28.2% | 12.2% to 28.2% |
R code and output
arm <- c("SoloPath Sheath")
n <- c(90)
events <- c(17)
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 SoloPath Sheath 90 17 18.9 11.4 28.5 12.1 28.2 12.2 28.211. Multiplicity, Missing Data and Analysis Populations
The registry record lists two outcome measures: vascular access site complications as the primary outcome and bleeding complications at the access site as a secondary outcome. It does not report results or analyses for either outcome. A multiplicity adjustment or strategy for handling multiple outcomes is not reported in the registry record.
General: when several outcomes or statistical tests are examined, the chance of at least one apparently notable result can increase if each is interpreted separately. Researchers may address this by defining a primary outcome in advance and specifying how secondary outcomes will be interpreted or adjusted. The registry record identifies a primary outcome, but does not report an analysis plan or a multiplicity procedure. No conclusion about how multiplicity was handled can be drawn.
Missing-data methods are also not reported in the registry record. It does not state how many participants had complete follow-up, how missing outcome information was classified, whether any imputation was used, or whether sensitivity analyses were performed. Enrollment is listed as 90, but the outcome-specific denominator and the analysis population are not reported. Enrollment therefore cannot be treated as the number analyzed.
General: missing outcome data can affect both the estimated event frequency and its uncertainty, especially if the chance of missingness differs according to outcome status or participant characteristics. A complete-case analysis, an imputation approach, and other methods rely on different assumptions. Without a reported approach and supporting details, the effect of missingness cannot be assessed for this study.
The record lists no analyses. It also does not report interim analyses, so whether any were planned or conducted is not reported in the registry record. No assumptions about analysis populations, exclusions, or handling of repeated records should be made.
12. What the Result Does, and Does Not, Mean
The registry record describes a retrospective, single-center collection focused on people who underwent TAVI with the SoloPath® sheath for femoral vascular access. It specifies a primary endpoint of VARC-2 defined vascular complications within 30 days and identifies access-site bleeding as a secondary outcome. These details define the subject of the investigation, but they do not establish an observed result.
The primary outcome count, outcome denominator, estimate of frequency, and uncertainty are not reported in the registry record. The secondary outcome result is also not reported. Accordingly, the record cannot support a numerical conclusion about how often either complication occurred in the study group, or how precisely any frequency was estimated.
The study does not report a comparator group or allocation method. It therefore does not establish a comparative estimate between the SoloPath® sheath and another access strategy. General: an observed outcome in a single group is descriptive; it cannot, on its own, separate the contribution of the intervention from participant characteristics, clinical practice, or other factors.
The enrollment listing of 90 should not be read as an endpoint denominator or as proof that all enrolled participants contributed outcome data. The registry record does not report the analysis population or missing-data handling. It also lists no analyses, which means no statistical result is available in the record to assess.
These limitations do not mean that an outcome did or did not occur. They mean that the registry information does not report the result needed to quantify it. General: interpretation of an observational complication study depends on transparent outcome counts, denominators, follow-up completeness, and, for comparative claims, a suitable comparison and analysis. Those details cannot be inferred from study completion or from the outcome definitions alone.
The record can therefore be used to identify the study’s scope, setting, outcome definitions, and stated timeframe. It cannot establish a complication rate, comparative benefit or harm, or the precision of an estimate. No treatment recommendation follows from the registry information.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of the difference between a defined clinical question and a reported result. The record specifies the population of interest in broad terms, the access device, the primary complication endpoint, and a 30-day timeframe. It also identifies access-site bleeding as a secondary outcome. Yet the outcome values and analyses are not reported in the registry record.
That distinction matters because an endpoint definition alone does not tell readers how many participants experienced an event. Nor does enrollment establish the number with complete outcome information. Reporting an event count with its denominator would allow a descriptive frequency to be interpreted; reporting an uncertainty interval would indicate its precision. Neither is available in the registry record.
The single-center retrospective design also makes the comparison question important. The study is focused on SoloPath® sheath use, while a comparator and allocation method are not reported. A descriptive result from this group, even if available, would not by itself quantify how outcomes differ under another approach. General: comparative interpretation requires a suitable contrast and consideration of differences in who receives each strategy.
The registry record lists no analyses. This makes the reporting gap explicit: readers cannot evaluate a statistical test, adjustment, missing-data approach, or analysis population. The record can still clarify the intended outcome and context, but cannot answer the quantitative question posed by its title. It illustrates why transparent outcome reporting, denominators, and methods are essential for interpreting a completed study.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main trial-specific limitation in the registry record is the absence of outcome results. Although it defines vascular access site complications as the primary endpoint and access-site bleeding as a secondary endpoint, the observed counts and denominators are not reported in the registry record. The frequency and precision of either outcome therefore cannot be assessed.
The study is described as retrospective and single-center. The record does not report how participants were selected, which records were eligible, or whether outcome information was complete. Enrollment is listed as 90, but that does not identify the number included in either endpoint analysis. The analysis population and missing-data handling are not reported in the registry record.
The recorded study arm focuses on SoloPath sheath use. A comparator is not reported, and allocation is not stated. This restricts interpretation to the stated study focus; a relative effect against another access strategy cannot be estimated from the registry information. The record does not report adjustment for participant differences or other potential confounding factors.
Although the primary endpoint names VARC-2, details of event ascertainment, classification, and review are not reported in the registry record. The precise operational process for applying the definition is therefore unknown. The registry also lists no analyses, and a statistical analysis plan, sample-size justification, interim analyses, and multiplicity approach are not reported.
These are limitations of what the registry record documents. They do not establish that particular procedures were absent from the study; they mean those procedures are not reported in the registry record and cannot be evaluated from it.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Retrospective Study Evaluating the Use of the SoloPath® Sheath in Reducing Vascular and Bleeding Complications — NCT02297308.
- Registry record last updated 2016-02-18; status last verified 2016-01.
- Results first posted 2016-02-18.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT02297308 is a completed, retrospective, single-center study sponsored by Terumo Medical Corporation. Its stated focus is TAVI with a SoloPath® sheath used for femoral vascular access. The registry lists enrollment as 90, with study start 2014-10 and primary completion 2015-03.
The primary outcome is the number of participants with VARC-2 defined vascular complications within 30 days of TAVI. Access-site bleeding complications are listed as a secondary outcome. The record describes one SoloPath Sheath arm; allocation and a comparator are not reported in the registry record.
The registry record lists two outcome measures and no analyses. It does not report outcome counts, denominators, estimates, confidence intervals, missing-data methods, or an analysis population. The record therefore identifies the study question and design but does not provide quantitative results for interpreting either outcome.