A Post Market Study on the Use of Cormatrix® Cangaroo ECM® (Extracellular Matrix) Envelope: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Post Market Study on the Use of Cormatrix® Cangaroo ECM® (Extracellular Matrix) Envelope (NCT02530970), a registered phase not stated study. The primary outcome is Proportion of Subjects With ECM Related Adverse Events.

2. Clinical Question

This is a descriptive post-market question, rather than a question about whether one assigned treatment performs better than another. The record identifies a single CanGaroo group in the safety information, with 1025 participants at risk and 40 participants with serious adverse events. Those figures concern serious adverse events generally; they should not be treated as the primary ECM-related outcome unless the record explicitly identifies them as such. It does not provide a separate reported result for the primary outcome in the registry record for this analysis.

The study can therefore contribute information about recorded events among participants observed after use of the envelope. It cannot, from the information in the registry record, establish how event experience would compare with an untreated group or another device. Nor does the record specify a causal question, a comparator group, or an adjustment strategy for differences among participants. The intended clinical question is consequently best read as surveillance and description of observed experience, with interpretation bounded by the outcome definitions and follow-up information that are actually reported.

3. Trial Design

The SECURE Study is described as a post-market observational study intended to gather additional information on use of the CorMatrix® CanGaroo ECM® Envelope. The registry lists cardiovascular disease as the condition, Elutia Inc. as the sponsor, and enrollment of 1025. Its status is COMPLETED. The listed study start is 2015-10, and primary completion is 2017-12.

Because the design is observational, the record does not describe participants being randomly assigned to different study treatments. Allocation is not stated, and the safety listing identifies a CanGaroo group rather than a randomized control comparison. The record itself cautions that the arms are not a like-for-like control comparison. A comparative treatment effect should therefore not be inferred from any arm-based figures.

The primary outcome concerns ECM-related adverse events, described as events collected at all study visits. The listed analysis population includes all study participants. Participants were followed for an average of 235.0 days. That is an average follow-up duration; the registry record does not specify the range of follow-up times or give participant-level observation periods.

The registry lists two outcome measures and no analyses. The detailed statistical analysis plan, any planned interim analyses, sample-size justification, and approach to confounding are not reported in the registry record. The sample-size assumptions associated with planning illustrations are not the study’s own design justification. The illustrations assume a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; they describe hypothetical planning based on a stated fraction of the observed effect. They do not establish that the observational study was designed with those assumptions, and they are not observed power.

These design features define the scope of interpretation. The study can describe events recorded during follow-up in the observed group. Without a stated randomized comparator and a reported comparative analysis, it does not provide a controlled estimate of what would have happened under a different treatment or in the absence of the envelope.

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: Analysis population includes all study participants.

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 Proportion of Subjects With ECM Related Adverse Events, measured over Participants were followed for an average of 235.0 days..

The primary outcome is titled “Proportion of Subjects With ECM Related Adverse Events.” Its listed unit is participants, and its measurement is a count of participants. The registry says the analysis population includes all study participants and that ECM-related adverse events were collected at all study visits. Follow-up is described as an average of 235.0 days.

The outcome is intended to capture whether participants experienced an adverse event considered related to the extracellular matrix envelope. Counting affected participants gives a direct description of how many people in the stated analysis population were recorded as having such an event. It differs from counting every event: one participant may have more than one event, but a participant count concerns whether a person had an event, not the total number of event episodes.

The title uses the word “Proportion,” but the recorded measurement is a count. The registry record does not provide a separate primary-outcome result or the numerator and denominator needed to interpret a reported proportion. The serious-adverse-event count in the safety information is not automatically the primary endpoint: it is a safety figure, and the record does not state that all serious events were ECM-related.

In general, this type of endpoint is used to summarize participant-level occurrence over a defined observation period. Its interpretation depends on a clear event definition, attribution rules, and consistent observation. The registry does not report further details of those rules, such as how relatedness was determined or how incomplete follow-up affected outcome classification. Without those details and a distinct outcome result, the measure’s intended role is clear, but its observed primary-outcome value cannot be evaluated from the registry information.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a participant-level binary outcome: whether a participant had an ECM-related adverse event. A binary outcome has two possible states for each participant, such as event recorded or no event recorded. The listed unit is participants, and the measurement is a count of participants rather than a count of every event episode. In general, this distinction matters because multiple event episodes in one person do not necessarily correspond to multiple affected participants.

What does a participant count tell us?

A count is a descriptive summary of the number of people classified as having an event. To interpret it as a proportion, the relevant denominator and the event definition must also be clear. The endpoint title uses the word “Proportion,” but the measurement is listed as a participant count. The registry record does not include a distinct primary-outcome result in the registry record for this analysis, so no proportion or uncertainty interval can be described for that endpoint.

The safety information uses “at risk” counts and counts of participants affected. For the CanGaroo group, 1025 participants are listed as at risk for serious adverse events, and 40 as affected. The record also lists 0 participants affected by other adverse events and 17 deaths. These are separate registry safety entries. They should not be combined into a single outcome, because their definitions and overlap are not described. In general, one participant may appear in more than one safety category, and the registry does not state whether that occurred in this study.

Why does observation time matter?

The registry reports an average follow-up of 235.0 days. In general, a participant count does not account for differences in how long people were observed. If observation time varies, people followed longer may have more opportunity for an event to be recorded. Time-to-event methods can use the timing of events and censoring information to address observation periods, but the registry entries do not report event times, censoring details, or a time-to-event analysis. The average follow-up alone cannot supply those details or convert the counts into rates.

What can be concluded from the design?

This is an observational post-market study, not a randomized comparison. In general, random assignment can help make treatment groups comparable at baseline, while observational groups may differ in factors related to both treatment and outcome. Such differences can complicate causal interpretation. Here, allocation is not stated, and the record expressly cautions that the arms are not a like-for-like control comparison. No adjustment method or comparative model is reported. The event counts therefore describe the recorded experience of the listed group; they do not isolate an effect attributable to the envelope.

The registry lists no analyses. A statistical analysis plan, including any planned model, treatment of confounding, interim analysis, and inferential procedure, is not reported in the registry record. Confidence intervals and hypothesis tests are also not reported in the registry record. In general, confidence intervals convey uncertainty about an estimated quantity, while hypothesis tests assess compatibility with a specified null hypothesis under model assumptions. Neither can be reconstructed from the listed counts without making assumptions or undertaking calculations that the registry does not report.

How should planning calculations be read?

The planning illustrations are described as calculations based on the observed effect, not as the trial’s own design. Their stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The effect to detect is a stated fraction of the observed effect. These are hypothetical planning conditions, not evidence that the study used a randomized two-arm design or those assumptions in its conduct.

Sample-size illustrations answer a planning question: how many participants per arm might be needed under specified assumptions to target a chosen power for a chosen effect. They do not report what happened in the study, and they are not observed power. Because the study is observational and no like-for-like control comparison is described, such illustrations should not be interpreted as a reconstruction of its actual design or as proof that the study was adequately powered. The registry’s own sample-size justification is not reported.

In general, the normal approximation is a method for approximating the sampling distribution of an estimate under specified conditions. For binary outcomes, the quality of an approximation can depend on the event frequency and the amount of information available. The registry does not report a model check or a justification for applying a particular approximation to the primary endpoint. Those matters cannot be resolved from the descriptive safety counts alone.

Why do event labels need care?

“Serious,” “other,” and “ECM-related” describe different aspects of safety information. Seriousness concerns an event classification; relatedness concerns whether the event was attributed to the envelope. A serious event is not automatically ECM-related, and a related event need not necessarily be serious. The registry gives a primary endpoint framed around ECM-related events and separately lists serious and other adverse-event counts. No cross-classification is reported, so those categories should remain distinct in interpretation.

The named serious-event terms have percentages, but the registry entries do not state whether those percentages refer to participants, events, or another denominator, nor whether terms overlap. In general, percentages for event terms are interpretable only with clear denominators and coding rules. The values should be read as the listed percentages associated with each term, not combined or treated as a complete distribution of all safety outcomes.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and no analyses. It does not report a statistical analysis plan, identify a hierarchy among outcomes, or describe a multiplicity adjustment. Multiplicity arises when several outcomes or statistical tests are assessed; in general, testing more hypotheses can increase the chance of at least one apparently notable result under a global null. Whether that issue applied to the study’s planned analyses cannot be determined because the analysis plan and analyses are not reported in the registry record.

The primary-outcome population is described as all study participants, but the record does not explain how missing outcome observations were handled. It does not report the number of participants with unavailable endpoint data, reasons for missingness, imputation methods, or sensitivity analyses. Missingness can matter because an observed-case summary may not represent participants without recorded follow-up, especially if missingness is related to health status or event occurrence. That is a general concern, not a claim about what happened in this study.

The average follow-up is 235.0 days, but participant-level follow-up completeness and loss to follow-up are not reported in the registry record. The collection of ECM-related adverse events at all study visits does not, by itself, specify how unobserved visits or incomplete records were handled.

The registry’s statement that the analysis population includes all study participants identifies the intended population description, but it does not establish how every participant contributed to every outcome. The record does not provide an analysis population count for the primary endpoint or explain exclusions, if any. No further assumptions about missing data, multiplicity control, or analysis-set construction can be made from the stated information.

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 3% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: pocket infection (1.2%), pain (0.5%), hematoma (0.5%), syncope (0.2%), superficial cellulitis (0.2%).

The CanGaroo safety listing reports 1025 participants at risk for serious adverse events, 40 participants affected by serious adverse events, 0 participants affected by other adverse events, and 17 deaths. These are counts as recorded in the registry. The record does not state whether the deaths were attributed to the envelope, whether they were included among serious adverse events, or whether participants could appear in more than one category.

The listed serious-event terms are Pocket Infection at 1.2%, Pain at 0.5%, Hematoma at 0.5%, Syncope at 0.2%, Superficial Cellulitis at 0.2%, and COPD Exacerbation at 0.2%. The record does not explain the denominator or coding basis for these term percentages, or whether one participant could contribute to more than one term. They should be read as the reported values for the named terms, not added together or treated as a complete account of all events.

These safety figures are distinct from the primary ECM-related adverse-event endpoint. The registry does not provide a cross-tabulation connecting seriousness, relatedness, and death. Nor does it report time-adjusted rates or a comparator suitable for estimating relative risk. The average follow-up was 235.0 days, but this does not establish equal observation time for each participant. The counts describe recorded safety information and do not establish causation.

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

The registry record supports a descriptive account of a completed post-market observational study of the CorMatrix® CanGaroo ECM® Envelope. It reports a CanGaroo safety group, serious-adverse-event and other-adverse-event counts, deaths, and several serious-event terms with percentages. The study objective was to collect additional information about use of the envelope, and participants were followed for an average of 235.0 days.

The record does not provide a reported result for the primary endpoint in the registry record for this analysis. Although the endpoint title refers to a proportion of subjects with ECM-related adverse events, the listed measurement is a participant count. The serious-adverse-event count is not a substitute for the primary outcome, because the registry does not say that those events were related to the ECM. The categories of seriousness, relatedness, and death cannot be assumed to coincide.

These data do not show what would have occurred in comparable participants who did not use the envelope or received a different device. The study is observational, allocation is not stated, and the record cautions against treating the arms as a like-for-like control comparison. Without an appropriate comparison and a reported analysis accounting for relevant differences, observed event counts cannot identify a causal effect.

In general, a registry count can document events recorded in a study population, but its interpretation depends on event definitions, observation time, completeness of follow-up, and the way participants are classified. The registry does not report enough detail to assess all of those aspects for the primary endpoint. It also does not report confidence intervals, hypothesis tests, or an analysis plan that would quantify uncertainty or explain how comparisons were intended to be made.

The appropriate conclusion is therefore limited to what is explicitly recorded: the safety counts and named event-term percentages describe entries for the CanGaroo group. They do not establish that the envelope caused or prevented events, and they do not establish a comparative safety advantage. The planning illustrations, if considered, concern hypothetical sample-size requirements under stated assumptions; they are not observed trial power or findings about treatment effect.

13. Why This Trial Matters Statistically

Post-market observational studies address a different statistical task from randomized trials. They can collect information about how a device is used and what events are recorded in routine or study follow-up. For the SECURE Study, the registry describes active collection of additional information on the CorMatrix® CanGaroo ECM® Envelope and identifies cardiovascular disease as the condition. The completed record lists enrollment of 1025 and an average follow-up of 235.0 days.

The statistical value of such a record depends on distinguishing descriptive surveillance from causal comparison. Counts of affected participants and event terms can describe recorded safety experience. They do not, without an adequate comparator and a suitable analysis, show whether observed events are more or less frequent because of the device. The record appropriately needs to be read in light of its observational design and its warning that arms are not a like-for-like control comparison.

This trial also illustrates why endpoint labels and measurements need to be read together. The primary outcome title refers to a proportion, while the listed unit and parameter describe a participant count. The safety information gives serious-event counts but not a separate reported primary ECM-related outcome. Keeping those measures distinct avoids treating a broad safety classification as a measure of device-related events.

For biostatisticians and clinical researchers, the record highlights the importance of transparent reporting: outcome definitions, denominators, observation time, missing-data handling, analysis populations, comparator construction, and planned methods all affect interpretation. Several of these details are not reported in the registry record. Identifying those gaps is not a claim that an analysis was necessarily flawed; it marks the limits of what can be inferred from the registry’s documented information.

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 central limitation is that the registry record does not include a separate reported result for the primary ECM-related adverse-event outcome in the registry record for this analysis. The endpoint title refers to a proportion, but the listed measure is a participant count. The serious-adverse-event count cannot fill this gap because the record does not report which serious events, if any, were considered ECM-related.

The study is observational, allocation is not stated, and the record says the arms are not a like-for-like control comparison. A causal or comparative interpretation is therefore not supported by the posted information. The registry does not report adjustment for confounding or describe a comparison model. It also does not provide a detailed account of how participants came to use the envelope.

Follow-up is described by an average of 235.0 days, but individual follow-up duration, event timing, and completeness of observation are not reported in the registry record. The record does not explain how missing visits or missing endpoint information were handled. These omissions limit assessment of whether event ascertainment was complete and how differences in observation time might affect event counts.

The safety listing reports serious events, other events, deaths, and serious-event terms, but does not explain overlap among categories or the denominator and coding basis for the term percentages. It does not state whether deaths were related to the envelope or included in another category. The registry also does not report confidence intervals, hypothesis tests, or a statistical analysis plan. These limitations constrain precision and interpretation; they do not establish that any particular event was caused by or unrelated to the envelope.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Post Market Study on the Use of Cormatrix® Cangaroo ECM® (Extracellular Matrix) Envelope — NCT02530970.
• Registry record last updated 2023-07-21; status last verified 2023-07.
• Results first posted 2020-03-11.
• 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 record describes the SECURE Study, a completed post-market observational study of the CorMatrix® CanGaroo ECM® Envelope. The stated objective was to gather additional information about use of the envelope. The listed condition is cardiovascular disease, the sponsor is Elutia Inc., enrollment is 1025, the study start is 2015-10, and primary completion is 2017-12.

The primary outcome is titled “Proportion of Subjects With ECM Related Adverse Events.” It is measured as a participant count, with events collected at all study visits; the analysis population is described as all study participants. Average follow-up was 235.0 days. The registry entries available for this analysis do not include a reported primary-outcome result.

For the CanGaroo group, the registry lists 1025 participants at risk for serious adverse events, 40 affected by serious adverse events, 0 affected by other adverse events, and 17 deaths. It also lists serious-event terms with percentages. The study is observational, allocation is not stated, and the record cautions that the arms are not a like-for-like control comparison. No analyses are listed, and the statistical analysis plan and missing-data methods are not reported in the registry record.