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 Cardioneuroablation for Neurocardiogenic Syncope (NCT02009982), a randomized na study. The primary outcome is Syncope Recurrence Rate.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02009982 |
| Phase | NA |
| Condition | Neurocardiogenic Syncope, Vasovagal Syncope |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 3 |
| Arms in the primary outcome | n/a |
| Lead sponsor | David B. De Lurgio |
| Results posted | Yes |
2. Clinical Question
Population
People with neurocardiogenic syncope, also called vasovagal syncope, were the intended study population. The registry describes syncope as passing out and links this condition to sudden drops in heart rate or blood pressure. It gives no further participant characteristics or eligibility details in the outcome information.
Intervention
The intervention was cardioneuroablation, a procedure using the Biosense Webster Navistar ThermoCool Diagnostic/Ablation Deflectable Tip Catheter. The registry describes the procedure’s goal as identifying and treating areas in the heart believed to initiate the reflex associated with syncope.
Comparator
The comparison group was to continue standard medical therapy without cardioneuroablation. The registry names medications used for neurocardiogenic syncope in its background description, but does not report which specific medication or regimen each participant received.
Primary question
The primary endpoint was recurrence of syncope within the 12 Months follow-up protocol. The intended comparison was whether recurrence differed between people assigned to cardioneuroablation and people assigned to standard medical therapy. No data were analyzed for this endpoint because enrollment was low.
This is a question about a clinical outcome after treatment assignment, not simply whether the procedure can be performed or whether a short-term physiological change occurs. A randomized comparison can, in principle, help distinguish outcome patterns between assigned groups, but a result requires outcome data and an analysis. The registry record reports neither a primary-outcome estimate nor an inferential comparison. It therefore does not establish how often syncope recurred in either group or how the groups compared.
3. Trial Design
The study is listed as randomized, with a parallel-group model and no masking. One group was assigned to cardioneuroablation and the other to standard medical therapy. The registry lists enrollment of 3 and status as completed. The study start is recorded as 2013-12, and primary completion as 2015-12. The phase is listed as NA.
In a parallel-group design, participants are assigned to a group and the outcomes of those groups are compared. Random allocation is intended to reduce systematic differences in characteristics that could otherwise influence the comparison. It does not guarantee that the groups will be similar in every respect, particularly when enrollment is very low. In this study, the adverse-event record lists 1 participant at risk in the cardioneuroablation group and 2 in the standard medical therapy group.
No masking was used. This means the registry does not describe the study as one in which treatment assignment was concealed from participants or study personnel through masking. For outcomes involving reported symptoms, knowledge of assignment can be relevant to how outcomes are reported or assessed; the registry does not describe specific procedures for reducing that possibility.
The registry describes the primary endpoint as syncope recurrence within 12 months, but states that no data were analyzed because of low enrollment. It reports no analysis results for this endpoint. The record lists serious adverse events as a secondary outcome, while the adverse-event figures are reported separately by group. Details such as allocation procedures, the planned analysis population, and whether any interim analyses were intended are not reported in the registry record.
The record’s completion status indicates that the study is marked completed; it does not mean that the planned primary outcome was analyzed or that a treatment comparison was reported. The distinction matters: study status describes the administrative state of the trial, whereas evidence about the primary question requires usable outcome data and an analysis.
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 | Cardioneuroablation | Standard Medical Thearpy |
|---|---|---|
| STARTED | 1 | 2 |
| COMPLETED | 1 | 2 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: No data was analyzed due to low enrollment.
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 | Cardioneuroablation | Standard Medical Thearpy | Total |
|---|---|---|---|---|
| Participants analysed | 1 | 2 | 3 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | 2 | 3 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 1 | 2 | 3 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | participants | 1 | 2 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Syncope Recurrence Rate, measured over 12 Months.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was recurrence of syncope during the 12 Months follow-up protocol. It focuses on whether participants experienced another episode of the condition being studied after assignment to treatment. Recurrence is directly relevant to the study question because the stated purpose was to evaluate cardioneuroablation for neurocardiogenic syncope.
General statistical context: a prespecified primary endpoint provides a main outcome around which a trial’s principal comparison can be organized. Choosing an outcome tied to the clinical question helps make the result interpretable: the reader can see what was measured, over what timeframe, and in which study groups. For a recurrence outcome, a complete analysis would need to define how recurrence was identified, how follow-up was handled, and how participants with incomplete observation were treated analytically. Those operational and analysis details are not reported in the registry record.
The registry states that no data were analyzed for the primary endpoint because enrollment was low. It therefore reports no recurrence counts, group-specific recurrence rates, effect estimate, confidence interval, or test of the group comparison. The endpoint is described, but its result is unavailable. The absence of an analyzed result is not evidence that recurrence did or did not occur; it means the registry record does not provide an analyzed outcome for answering the primary question.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized comparison of cardioneuroablation and standard medical therapy, but it does not report an analyzed primary outcome. The primary endpoint was syncope recurrence within 12 Months. The record explicitly says no data were analyzed for that endpoint because enrollment was low. Consequently, there is no reported group-specific recurrence result and no estimated difference between the assigned groups to interpret.
Without an outcome estimate, the record cannot show the direction or magnitude of a treatment-group contrast for syncope recurrence. It also cannot show how precise such a contrast would be. A confidence interval would ordinarily communicate the range of values compatible with the data and analysis under the method’s assumptions; no confidence interval for the primary endpoint is reported. Likewise, no primary-outcome significance test or p-value is reported. Neither a positive nor a negative efficacy conclusion follows from these omissions.
Enrollment was 3. The adverse-event record gives group-specific at-risk counts of 1 for cardioneuroablation and 2 for standard medical therapy. These small denominators make the adverse-event counts descriptive of the participants represented in the record; they do not provide a stable basis for broad comparison. The serious adverse-event figures list 0 affected among 1 at risk in the cardioneuroablation group and 0 affected among 2 at risk in the standard medical therapy group. The other-adverse-event figures list 1 affected among 1 at risk and 2 affected among 2 at risk, respectively. These counts do not substitute for a primary-outcome analysis.
General statistical context: when counts are sparse, a single participant’s outcome can substantially change the apparent pattern. Estimates based on very limited data are typically imprecise, and conventional inferential procedures may be difficult to interpret. Here, the more fundamental limitation is that the registry reports no analyzed primary outcome at all. The record does not support an efficacy estimate, a comparative safety conclusion, or a claim about what would happen in a larger population.
The study is marked completed, but completion does not resolve the missing primary analysis. The record reports no analysis results among its listed analyses. It also does not report why enrollment was low beyond identifying it as the reason no primary endpoint data were analyzed. The appropriate reading is therefore narrow: the registry documents the design and some adverse-event counts, while the stated primary question remains unanswered in the posted results.
9. Statistical Methods Explained
What does randomization contribute?
General statistical context: randomization assigns participants to study groups by chance, aiming to make treatment assignment independent of participant characteristics at the point of assignment. This can help support a fair comparison, because systematic differences between groups are less likely to be caused by the assignment process. Randomization does not ensure that groups will be balanced in a small study, and it cannot replace outcome data. The registry identifies the study as randomized, but further details about how allocation was generated or concealed are not reported in the registry record.
In a parallel-group trial, participants remain assigned to their respective comparison groups rather than crossing between treatments as part of the listed model. The registry identifies cardioneuroablation and standard medical therapy as the groups. The primary comparison would concern syncope recurrence in those groups during the stated follow-up. Since no primary outcome data were analyzed, randomization does not yield a reported treatment-effect estimate in this record.
What would a treatment-effect estimate mean?
General statistical context: an effect estimate summarizes the difference or other contrast between groups for a defined outcome. Its meaning depends on the outcome definition, analysis population, follow-up, and statistical method. A confidence interval describes statistical uncertainty around an estimate under the assumptions of the analysis; it is not a guarantee that the true value lies within the interval. A p-value, when reported, describes how compatible the observed data are with a specified null model, conditional on the analysis assumptions. Neither measure establishes clinical importance by itself.
No primary-outcome effect estimate, confidence interval, or p-value is reported. It would not be appropriate to infer any of these from the adverse-event counts: they refer to a different outcome, and the registry does not present them as an analysis of syncope recurrence. It would also be inappropriate to treat the absence of an analysis as a result of no difference.
How should sparse counts be read?
General statistical context: a count is a direct description of the recorded number of affected participants, while a rate or proportion requires a defined denominator and interpretation. Even when a denominator is reported, very small groups offer little information about how frequently an event might occur beyond the participants observed. A count of no reported events in a small group does not establish that the event cannot occur or that the risk is absent.
The adverse-event record lists the number at risk and the number affected separately for serious and other adverse events. These figures can be read descriptively by group, but they do not provide a precise estimate of a population event rate. The record does not give a confidence interval or a comparative statistical test for these adverse-event counts. It also does not report deaths as a numerical value; deaths are not reported in the registry record.
What is the role of the planning illustration?
General statistical context: sample-size planning asks how many participants would be needed under specified assumptions to target a chosen level of statistical power for a defined effect. Such calculations depend on features including the significance level, allocation, outcome type, and assumed effect. A planning calculation is not an observed result and does not establish that a study had adequate power after enrollment.
The registry describes its planning illustration as using a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the effect to detect expressed as a stated fraction of the observed effect. It says that time-to-event illustrations use total events, while other illustrations use participants per arm. These are planning assumptions, not a reported analysis plan or evidence about the trial’s primary outcome. The registry record does not report a trial-specific sample-size justification. Because no primary outcome data were analyzed, a planning illustration cannot be read as observed power or as an estimate of the treatment effect in this study.
What can be concluded from the listed analyses?
The registry reports 0 analyses and says no primary-outcome data were analyzed because of low enrollment. General statistical context: an analysis must connect the recorded outcomes to a defined comparison and method before an effect estimate can be interpreted. When an analysis is absent, the reader cannot evaluate adjustment choices, model assumptions, handling of follow-up, or uncertainty from the primary endpoint. Those details are not reported in the registry record, and no statistical method for a primary-outcome comparison can be inferred from the randomized design alone.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists syncope recurrence as the primary endpoint and Incidence of Serious Adverse Events as a secondary outcome. It reports 0 analyses and says no data were analyzed for the primary endpoint because enrollment was low. No testing strategy for multiple outcomes, endpoints, or comparisons is reported in the registry record. Therefore, the record does not establish whether a multiplicity adjustment was planned or used.
General statistical context: when several hypotheses are tested, the chance of at least one apparently unusual result can increase if each is assessed independently. A prespecified strategy can clarify which outcomes are confirmatory and how the interpretation of multiple tests should be handled. Here, there are no reported primary-outcome tests to assess, and the record does not provide enough detail to characterize a multiplicity procedure.
The primary endpoint description does not provide an analyzed set of participants, a count of participants with available follow-up, or a description of how incomplete follow-up was handled. The registry states that no data were analyzed because of low enrollment, but does not explain the participant-level availability of endpoint data. It is therefore not possible to distinguish uncollected outcomes from collected but unanalyzed outcomes using the registry record.
The analysis population is not reported in the registry record. In particular, the record does not specify whether an intention-to-treat, per-protocol, or other population was intended for the primary comparison. No imputation method, censoring rule, or missing-data sensitivity analysis is reported. These absences prevent evaluation of how missing outcome information might have affected a treatment comparison. They should not be interpreted as proof that missing values occurred or that any particular method was used.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Cardioneuroablation | 0 | 1 | 0.0% |
| Standard Medical Thearpy | 0 | 2 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Cardioneuroablation | 1 of 1 |
| Standard Medical Thearpy | 2 of 2 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Cardioneuroablation | Standard Medical Thearpy |
|---|---|---|---|
| Syncope | Nervous system disorders | 0 of 1 | 2 of 2 |
| Chest Pain | Cardiac disorders | 1 of 1 | 0 of 2 |
| Tremors | Nervous system disorders | 1 of 1 | 0 of 2 |
| Upper Respiratory Infection | Infections and infestations | 1 of 1 | 0 of 2 |
| Angina | Cardiac disorders | 1 of 1 | 0 of 2 |
| Edema | Blood and lymphatic system disorders | 1 of 1 | 0 of 2 |
| Shingles | Skin and subcutaneous tissue disorders | 0 of 1 | 1 of 2 |
| Urinary Tract Infection | Renal and urinary disorders | 0 of 1 | 1 of 2 |
The adverse-event record lists serious adverse events by group. For cardioneuroablation, it reports 0 affected among 1 participant at risk. For standard medical therapy, it reports 0 affected among 2 participants at risk. These are the recorded serious-event counts, not estimates of the frequency of serious events in a broader population. The record also lists other adverse events: 1 affected among 1 at risk in the cardioneuroablation group, and 2 affected among 2 at risk in the standard medical therapy group.
General statistical context: adverse-event counts are most useful when read alongside the number of participants observed, the event definitions, and the observation period. Small groups provide limited information about uncommon events, and a count of 0 does not establish that an event is impossible or that risk is absent. The registry does not report a comparative statistical analysis for these figures, and they should not be treated as a test of safety differences between groups.
The deaths field has no numerical entry for either group; deaths are not reported in the registry record. That is different from a reported count of 0. The registry lists serious adverse events as a secondary outcome, but the available record does not give event terms among the serious events. These safety figures should be read as limited descriptive counts rather than a comprehensive assessment of comparative safety.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, parallel-group study was conducted to compare cardioneuroablation with standard medical therapy for neurocardiogenic syncope. Its primary endpoint was recurrence of syncope within 12 Months. It also documents enrollment of 3, completion status, and adverse-event counts by group. Those details describe the study and the available posted results.
The record does not establish whether cardioneuroablation changed syncope recurrence relative to standard medical therapy. No primary endpoint data were analyzed, and no group-specific recurrence results or treatment-effect estimates are reported. Accordingly, no conclusion about the direction, size, or precision of a difference in recurrence can be drawn from the posted results. An unreported result is not evidence of no effect, and it is not evidence of benefit.
The adverse-event counts do not answer the primary question. They are based on small at-risk groups and are descriptive; the registry reports no inferential comparison for them. The serious-event counts of 0 in each group cannot establish the absence of serious risk. The other-event counts likewise do not support a broad comparison or prediction beyond the participants recorded.
General statistical context: evidence from a randomized study depends not only on its design but also on adequate outcome ascertainment, a defined analysis, and uncertainty estimates. A randomized label alone cannot resolve an unanswered outcome question. Nor does a planning illustration serve as a substitute for analyzed results: it describes assumptions for planning, not what happened to participants.
The result therefore has a limited but clear meaning: the registry record documents the trial’s intended comparison, while the primary outcome remains unanalyzed because of low enrollment. It does not provide a basis for claims that either treatment is more effective or safer. The record also does not describe enough about outcome collection, analysis populations, or missing data to assess those aspects of the intended comparison.
13. Why This Trial Matters Statistically
This trial is statistically notable because its design and primary question are recorded, but its primary outcome was not analyzed. That distinction is important in clinical research: registration of a randomized comparison does not by itself produce an estimate of treatment effect. Readers need reported outcome data and an analysis to assess the result and its precision.
Enrollment of 3, with 1 participant at risk in the cardioneuroablation group and 2 in the standard medical therapy group in the adverse-event record, leaves very little information for comparing groups. General statistical context: limited enrollment tends to make estimates unstable and uncertainty large, even when outcome data are available. Here, the registry states that the primary outcome was not analyzed, so there is no estimate whose uncertainty can be quantified.
The record also illustrates why event counts and primary outcomes should not be conflated. Adverse-event figures are posted, but they do not measure syncope recurrence and do not supply a comparative efficacy result. Similarly, a planning illustration based on assumptions is not evidence that a planned or completed study had adequate information for its main question.
For biostatistical interpretation, the key lesson is to separate trial design, study status, descriptive counts, and analyzed endpoints. The study is listed as randomized and completed, yet the primary comparison remains unavailable. This makes transparent reporting of non-analysis important: it prevents readers from mistaking missing evidence for a null result and clarifies which questions the posted data can address.
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 most direct limitation is that the registry states that no data were analyzed for the primary endpoint because enrollment was low. The primary question concerns syncope recurrence within 12 Months, but the record provides no recurrence data, group comparison, effect estimate, or measure of precision. The intended efficacy comparison therefore cannot be assessed from the posted results.
Enrollment was 3, and the adverse-event record gives at-risk counts of 1 and 2 across the two groups. Such limited counts cannot support a reliable broad characterization of event patterns. The registry’s serious and other adverse-event figures are descriptive, with no reported comparative analysis. The deaths field contains no numerical entry, so deaths are not reported in the registry record rather than explicitly reported as 0.
Additional design and analysis details are not reported in the registry record. These include the allocation procedure, specific standard medical therapy received, the analysis population, handling of missing follow-up, and methods for analyzing the primary endpoint. The record also does not explain the low enrollment beyond identifying it as the reason that no primary endpoint data were analyzed. These omissions limit assessment of how the intended comparison would have been carried out.
The study is marked completed, but that status does not indicate that the primary outcome was analyzed. The registry reports 0 analyses. The record therefore offers limited information for evaluating the trial’s clinical question and does not support extrapolation to a broader population. These limitations concern the information recorded and should not be replaced with assumptions about unreported procedures or results.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Cardioneuroablation for Neurocardiogenic Syncope — NCT02009982.
- Registry record last updated 2016-11-04; status last verified 2016-09.
- Results first posted 2016-11-04.
- 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
NCT02009982 is a completed, randomized, unmasked, parallel-group study of cardioneuroablation versus standard medical therapy for neurocardiogenic syncope. Enrollment was 3. The primary endpoint was syncope recurrence within 12 Months.
The registry states that no primary endpoint data were analyzed because enrollment was low and reports 0 analyses. It provides adverse-event counts by group, but no analyzed comparison of syncope recurrence. The record therefore documents the intended study question and limited descriptive safety information, while leaving the primary outcome unanswered.