Surgical Treatment of Aortic Stenosis With a Next Generation, Rapid Deployment Surgical Aortic Valve: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Surgical Treatment of Aortic Stenosis With a Next Generation, Rapid Deployment Surgical Aortic Valve (NCT01700439), a na na study. The primary outcome is Number of Late Adverse Events Divided by Late Patient Years (Expressed as a Percentage) for the INTUTY Valve Implanted Cohort.

2. Clinical Question

3. Trial Design

The registry identifies this as a completed, single-group device study of the EDWARDS INTUITY valve system. The study title describes a multicenter experience, and the registry lists Edwards Lifesciences as the sponsor. The enrollment entry is 934. The recorded start date is 2012-09-26, and the primary completion date is 2021-05-26. The phase is listed as not applicable.

All enrolled subjects are described as receiving the valve system. Allocation is listed as not applicable, masking is none, and the model is single group. These features mean the record does not describe random assignment or a masked comparison between treatment groups. A cohort listed in the adverse-event information is not, by itself, evidence of a control arm. The listed commercially available valve cohort should not be treated as a randomized comparator on the basis of this record.

The primary outcome is a late adverse-event rate, with events occurring from 31 days through 8 years after implantation counted in its stated time window. The registry also lists 21 outcome measures. Secondary outcomes include technical and procedural success, time on cardiopulmonary bypass and cross clamp, intensive care unit days, New York Heart Association classification over time, and mean and peak gradient measurements over time.

The registry record does not report the protocol’s sample-size justification, a prespecified statistical analysis plan, or an interim-analysis plan. It records 0 analyses. That does not establish that no analyses were conducted; it means the record does not contain analysis entries in the information summarized for this study. The results described in the record should therefore be distinguished from unreported details about how investigators planned or performed 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

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The group of subjects that received the Edwards INTUITY surgical aortic heart valve.

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 Late Adverse Events Divided by Late Patient Years (Expressed as a Percentage) for the INTUTY Valve Implanted Cohort, measured over Events occurring ≥ 31 days and up through 8 years post-implant.

The primary endpoint is the number of late adverse events divided by late patient-years, expressed as a percentage. The event window begins at 31 days after implantation and continues through 8 years post-implant. The denominator is calculated from 31 days after implantation until the last follow-up visit or contact, or an adverse event, as described in the registry.

This is an event rate based on accumulated observation time, not simply the percentage of participants who experienced at least one event. A participant-time denominator can account for differing follow-up durations: people observed for different lengths of time contribute different amounts of time at risk. Counting events rather than only people with events can also represent repeated events, if those are included under the endpoint definition. The registry’s description does not specify additional rules for counting recurrent events.

Expressing events relative to patient-years is useful when follow-up time varies, but interpretation depends on both the event-counting rules and how observation time is accrued. A rate does not directly state an individual participant’s probability of an event. Nor does the rate alone show whether the event burden differs from another treatment, because the study is recorded as single group and no randomized comparator is specified.

The registry record gives the endpoint definition but does not report a numerical primary endpoint result or its precision. Without that estimate and an uncertainty interval, the magnitude and statistical uncertainty of the primary endpoint cannot be assessed from this record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a single-group study, with no allocation and no masking. This design can describe outcomes among people who received the device, but it does not create randomized treatment groups for estimating a causal contrast. An uncontrolled event rate can be informative about observed experience, yet it cannot by itself separate effects associated with the device from the influence of participant characteristics, clinical practice, follow-up, or other factors.

What does the primary rate represent?

In general, an event rate relates a count of events to time at risk or time under observation. Here, the stated numerator is the number of late adverse events, and the denominator is the sum of late patient-years. The registry expresses the quotient as a percentage by multiplying by 100. In plain terms, the measure describes event frequency relative to accumulated follow-up time, rather than the share of participants who ever experienced an event.

Patient-time is useful when observation lengths vary. Someone followed for a longer interval can contribute more time than someone followed for a shorter interval, according to the endpoint’s accrual rules. That can make a rate more interpretable than a raw event count when follow-up is unequal. It does not remove every source of bias: for example, the meaning of a rate can be affected if follow-up ends for reasons related to the likelihood of an event. The registry does not report whether or how such issues were assessed.

The endpoint specifies events from 31 days through 8 years after implantation. Late patient-years begin at 31 days after implantation and end at the last follow-up visit or contact, or an adverse event. The record does not report further details about recurrent-event handling, competing events, or how a participant’s time is treated after an event. Those details can matter when translating a rate into a clinical interpretation.

How should uncertainty be considered?

In general, a confidence interval describes the range of estimates compatible with the data and a stated statistical procedure. It helps show precision: a narrower interval indicates greater precision than a wider interval under the same approach. A point estimate without an interval can conceal substantial uncertainty. The registry record does not report a confidence interval for the primary endpoint, so its precision cannot be evaluated from the available record.

In general, a p-value addresses compatibility between data and a specified null model, conditional on the model’s assumptions. It is not a measure of effect size, clinical importance, or the probability that a treatment works. No primary endpoint p-value is reported in the registry record. Since no comparator is specified for the primary endpoint, a treatment contrast should not be inferred from the endpoint definition alone.

What does a single-group design permit?

A single-group study can report observed event counts, rates, and other outcomes among participants who received an intervention. Descriptive estimates can characterize the recorded study experience. A comparison against an external or historical group would require clearly defined data sources and methods to address differences between groups. The registry record does not describe such an analysis for the primary endpoint.

For an unadjusted comparison, differences in participant mix, care, outcome assessment, and follow-up can make groups unlike one another. Random assignment is one way to balance known and unknown factors on average, but this record lists allocation as not applicable. The cohort labels in the adverse-event listing should therefore not be interpreted as evidence of randomization or equivalence. No adjusted comparison method is reported in the registry record.

How do planning illustrations differ from results?

General sample-size planning asks how much information might be needed to detect a specified effect under chosen assumptions. The record’s planning illustration is described as using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect defined as a stated fraction of the observed effect. Time-to-event illustrations use a total event count; other illustrations use participants per arm. These are planning assumptions, not descriptions of the study’s own design or observed power.

The registry describes this study as single group, so an equal-allocation, two-arm planning illustration should not be mistaken for the actual design. The record does not report the trial’s own sample-size justification. A sample-size calculation is not an outcome, and it cannot establish that the study was adequately powered for every endpoint. No new calculation or inference about power is warranted from the endpoint definition alone.

What other methods are unreported?

The registry lists 21 outcome measures and 0 analyses. It does not report a full statistical analysis plan, model choices for outcome measures over time, adjustments for baseline characteristics, missing-data procedures, or multiplicity control. Those methods can affect how estimates and uncertainty are obtained. Their absence from the registry record does not prove that investigators did not use them; it means they are not described in the record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 21 outcome measures, including the primary late adverse-event rate and secondary measures concerning technical and procedural success, procedure duration, intensive care unit stay, functional classification, and valve gradients. When a study assesses multiple outcomes or performs repeated tests, the chance of at least one apparently notable result can increase. In general, multiplicity procedures can address that issue by defining which tests are primary or by adjusting interpretation. The registry record does not report a multiplicity strategy, a hierarchy of tests, or whether any adjustment was applied.

The record lists 0 analyses. It does not report a statistical analysis plan specifying models, covariate adjustment, repeated-measure methods, or rules for handling missing outcomes. Missing-data methods matter because an analysis based only on observed measurements can be affected if missingness is related to participant condition or outcome. The record does not state how missing data were handled, so no imputation or complete-case method should be assumed.

The primary endpoint population is described as subjects who received the Edwards INTUITY surgical aortic heart valve. The registry does not provide a fuller analysis-population definition, such as rules for inclusion, exclusions, or treatment of participants with incomplete follow-up. It also does not report whether all enrolled subjects contributed to each outcome. The stated enrollment of 934 should not be taken as the denominator for every endpoint.

These omissions limit the ability to reproduce or independently evaluate the analyses. They are limits of reporting in the registry record; they do not establish that the study team lacked a plan or did not conduct additional analyses.

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 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: arrhythmia - paroxysmal atrial fibrillation (paf) (24.5%), muscular skeletal/dermatologic - other (20.0%), nonspecific, unknown, or other body system - other complication (16.9%), thromboembolic event - stroke (12.2%), gastrointestinal - other (12.2%).

The adverse-event listing separates an Edwards TRANSFORM INTUITY Aortic Valve Study Cohort from a Commercially Available Aortic Valve Study Cohort. In the Edwards TRANSFORM INTUITY cohort, the record lists 885 at risk and 756 affected for serious events, 885 at risk and 868 affected for other events, and 178 deaths. In the commercially available cohort, it lists 49 at risk and 37 affected for serious events, 49 at risk and 47 affected for other events, and 8 deaths.

These entries are counts, not a randomized comparison. The study is recorded as single group with allocation not applicable, and the registry does not establish that the cohort listings are comparable. The counts also do not provide the timing or cause of deaths. The record’s leading serious-event terms include paroxysmal atrial fibrillation at 24.5%, muscular skeletal/dermatologic events classified as other at 20.0%, and nonspecific, unknown, or other body system complications at 16.9%. It also lists stroke at 12.2%, gastrointestinal events classified as other at 12.2%, and cardiovascular events classified as other at 11.9%.

The record does not clarify the denominator or detailed coding rules for each listed term. These percentages should therefore be read as registry-reported category values, not as rates calculated from the at-risk counts. A serious-event listing does not by itself establish causation by the device, and the record does not provide an adjusted safety comparison.

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

The record establishes that a completed, single-group study was registered for the EDWARDS INTUITY valve system and that the primary endpoint was defined in terms of late adverse events per late patient-years. It also lists secondary outcomes and adverse-event counts. This information describes the study’s stated scope and the kinds of outcomes recorded.

The record does not report a numerical primary endpoint result, a confidence interval, or a p-value. It therefore does not permit a judgment about the primary rate’s magnitude or precision. The adverse-event counts and category percentages provide additional descriptive information, but they are not a substitute for a reported primary endpoint estimate and do not establish a causal relationship with the device.

Because the study is recorded as single group, its findings cannot be interpreted as a randomized estimate of the difference between the valve and another treatment. The two cohort labels in the adverse-event record do not establish a like-for-like comparison. Differences between such cohorts could reflect ways participants were selected or followed, among other factors not detailed in the record.

The endpoint’s use of patient-years is relevant when follow-up duration varies, but it does not make a rate equivalent to an individual participant’s probability of experiencing an event. Nor does a rate alone describe event severity, timing, or the balance of potential benefits and harms. Additional definitions and results would be needed for those interpretations.

The record’s listed secondary outcome names identify additional areas assessed, but names alone do not show their results. Similarly, the listed sample-size illustrations are planning calculations under stated assumptions, not observed power and not evidence that the study’s design was based on those assumptions. Overall, the registry information supports a description of design and outcome definitions, but leaves key results and analysis details unreported.

13. Why This Trial Matters Statistically

This study illustrates why the outcome’s denominator matters. A count of late adverse events and a rate per late patient-years answer different descriptive questions. The rate incorporates accumulated follow-up time, while a participant-level proportion would describe the share of people with an event. Keeping those measures distinct avoids treating a time-based rate as a simple percentage of participants.

The registry also shows why design information is essential to interpretation. The study is single group, with allocation listed as not applicable and masking as none. Those design features define what kinds of conclusions the recorded data can support. Cohort labels appearing in safety information do not, without evidence of a comparative design and suitable analysis, create a reliable treatment contrast.

Another statistical lesson is that an endpoint definition and an endpoint result are not the same thing. The registry specifies the late-event window and patient-year calculation, but does not report the primary numerical estimate or its uncertainty. Without those, readers can understand what was intended to be measured but cannot assess the size or precision of the observed rate.

Finally, the record lists 21 outcome measures, yet does not report multiplicity methods, missing-data procedures, or a detailed analysis plan. These features influence how a set of results should be interpreted, especially when outcomes are assessed over time or when follow-up is incomplete. Clear reporting of the estimand, analysis population, assumptions, and uncertainty is important for evaluating clinical evidence. The absences in this record identify reporting limits; they should not be mistaken for proof about what investigators did outside the registry.

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 registry record does not report the primary endpoint’s numerical result or an uncertainty interval. This is the central limitation for interpreting the study’s stated primary question: the event-rate definition is available, but the observed rate and its precision are not.

The single-group design limits causal interpretation. There is no randomized comparator described, and the commercially available cohort in the adverse-event listing is not established as a control group. The record does not report methods for adjusting a comparison between the listed cohorts. Their counts should therefore be treated as descriptive entries rather than evidence of a treatment difference.

The registry does not report detailed rules for recurrent events, censoring, competing events, or follow-up completeness. Such rules can affect the numerator and denominator of a patient-time rate. It also does not report missing-data handling or a full analysis-population definition. The listed enrollment should not be assumed to be the denominator for every outcome.

The record lists 21 outcomes but does not describe a multiplicity plan, a hierarchy among outcomes, or a full statistical analysis plan. This makes it difficult to assess how the analyses were selected and how uncertainty across outcomes was considered. The record also does not report a sample-size justification for the actual single-group design. Planning illustrations using equal allocation between two arms are not a substitute for that justification and are not observed power.

Finally, the adverse-event information gives cohort-level counts and selected category percentages, but the record does not provide the event coding detail, timing, causes of deaths, or a comparative safety analysis needed for broader conclusions. These are limitations of what the registry record reports, not proof that further information does not exist.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Surgical Treatment of Aortic Stenosis With a Next Generation, Rapid Deployment Surgical Aortic Valve — NCT01700439.
• Registry record last updated 2023-05-19; status last verified 2023-05.
• Results first posted 2017-12-13.
• 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

NCT01700439 is a completed, single-group device study sponsored by Edwards Lifesciences. The registry lists enrollment of 934, a start date of 2012-09-26, and a primary completion date of 2021-05-26. The intervention is the EDWARDS INTUITY valve system, and the record states that enrolled subjects received it.

The primary endpoint is late adverse events divided by late patient-years, expressed as a percentage. Its event window runs from 31 days through 8 years after implantation. The record lists 21 outcome measures and 0 analyses.

The registry includes adverse-event counts for an Edwards TRANSFORM INTUITY Aortic Valve Study Cohort and a Commercially Available Aortic Valve Study Cohort. It does not identify these as randomized comparison arms. The primary endpoint estimate, its precision, the statistical analysis plan, multiplicity methods, and missing-data methods are not reported in the registry record.