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 Jewel Electrophysiology (EP) Lab Study (NCT05490459), a na na study. The primary outcome is Clinical Effectiveness of the Jewel.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT05490459 |
| Phase | NA |
| Condition | Sudden Cardiac Arrest |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 18 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Element Science, Inc. |
| Results posted | Yes |
2. Clinical Question
Population
The study summary describes adult cardiac patients, and the registry lists sudden cardiac arrest as the condition. The record gives an enrollment of 18. It does not report further eligibility criteria, such as the clinical circumstances required for participation or how participants were selected.
Intervention
The intervention was the Jewel Patch Wearable Cardioverter Defibrillator (P-WCD), a device evaluated in a single-arm, open-label study. The summary describes the purpose as evaluating the device’s defibrillation waveform.
Comparator
There was no randomized comparator group: the registry lists a single-group model and does not identify a control arm. That means the study does not provide a like-for-like between-group comparison. Any observed endpoint count would need to be interpreted as a result within the study group, not as an estimated difference between treatments.
Primary question
The primary endpoint asks how many participants had successful termination of life-threatening VT or VF after a single shock from the study device. The stated performance criterion is that the lower confidence limit exceed 62%, using a one-sided exact lower 97.4% confidence bound at one of three testing points. The observed count and confidence bound are not reported in the registry record, so whether the criterion was met cannot be determined from the posted results.
3. Trial Design
The Jewel Electrophysiology (EP) Lab Study is listed as a completed, single-group, open-label device study. Its intervention is the Jewel Patch Wearable Cardioverter Defibrillator (P-WCD), and the summary characterizes the study as an evaluation of the device’s defibrillation waveform in adult cardiac patients. The registry lists sudden cardiac arrest as the condition and an enrollment of 18.
The design does not include a randomized control group. The allocation field is listed as NA, and the study model is single group. Consequently, the design does not estimate a contrast between the device and a separate treatment or control group. The arm is described as Treatment, with the purpose labeled Safety and Effectiveness. The record lists no phase, which is shown as NA.
The study began on 2018-11-27, reached primary completion on 2021-10-07, and is marked COMPLETED. These dates describe the registry timeline; they do not establish when individual participants were enrolled, how long each participant was followed, or when endpoint assessments occurred. Those details are not reported in the registry record.
The primary endpoint is a participant count for successful single-shock termination of life-threatening VT or VF immediately following defibrillation with the study device. The registry states a performance criterion based on a one-sided exact lower 97.4% confidence bound and a threshold of 62%, with testing at one of three points. The observed endpoint count, denominator used for the endpoint analysis, confidence bound, and whether the criterion was met are not reported in the registry record.
The sponsor is Element Science, Inc. Further details about study conduct, device delivery, enrollment procedures, analysis populations, and the statistical plan are not reported in the registry record. The design therefore supports description of the study group, but does not by itself provide a controlled estimate of comparative effects.
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 | Treatment |
|---|---|
| STARTED | 18 |
| COMPLETED | 18 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: Treatment
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 | Treatment |
|---|---|---|
| Participants analysed | 18 | |
| Age, Continuous | years | 63.8 (28 to 80) |
| Sex: Female, Male: Female | Participants | 3 |
| Sex: Female, Male: Male | Participants | 15 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 |
| Race (NIH/OMB): Asian | Participants | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 |
| Race (NIH/OMB): White | Participants | 18 |
| Race (NIH/OMB): More than one race | Participants | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 |
| Body Mass Index (kg/cm^2) | kg/cm^2 | 28.3 (20.2 to 36.9) |
6. Primary Endpoint
The registry lists the primary outcome as Clinical Effectiveness of the Jewel, measured over Immediately following defibrillation with the study device..
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the count of participants who experienced successful termination of life-threatening VT or VF with a single shock from the study device. The listed assessment timeframe is immediately following defibrillation with the device. In practical statistical terms, this is a binary outcome at the participant level: each assessed participant either meets the endpoint definition or does not. The registry expresses the endpoint as a count of participants.
This type of endpoint is relevant to the stated purpose of evaluating a defibrillation waveform because it records whether the intended immediate response to a shock occurred. It is not a measure of longer-term outcomes, repeated device performance, or comparative effectiveness against another device. Those outcomes are not specified as the primary endpoint in the registry record.
The protocol description says success would be judged against a performance goal of 62%. The decision rule is based on whether the lower confidence limit exceeds that goal, using a one-sided exact lower 97.4% confidence bound at one of three testing points. This criterion describes how the endpoint was intended to be assessed; it does not establish that the goal was met.
The registry record does not report the observed count of successful terminations, the analyzed endpoint denominator, or the confidence bound. Therefore, the endpoint definition and decision criterion can be described, but the observed result cannot be interpreted from the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the clinical question and the intended decision criterion, but it does not post the primary endpoint result. It reports an enrollment of 18 and describes the endpoint as the count of participants with successful single-shock termination of life-threatening VT or VF. The observed count, analysis denominator, and associated confidence bound are not reported in the registry record. Without those values, it is not possible to assess how often the endpoint occurred in the study group or whether the stated performance criterion was satisfied.
The criterion requires the lower confidence limit to exceed 62%, using a one-sided exact lower 97.4% confidence bound at one of three testing points. A confidence bound represents uncertainty around an estimate; a lower bound is the value at the lower end of that interval. The registry description makes the bound, rather than the point estimate alone, central to the stated criterion. The threshold and method are reported, but the numerical bound is not. No conclusion about passing or failing the criterion follows from the criterion’s description alone.
The single-group design also limits what the study can establish. If a group-level endpoint estimate were available, it would describe outcomes in participants assessed with the device. There is no randomized comparator group in the registry record, so there is no direct randomized contrast from which to estimate a difference versus another device or treatment. In general, uncontrolled results can be affected by participant selection, study procedures, and other features of the setting; the record does not provide enough detail to assess those influences for this study.
The registry lists 18 participants at risk for serious adverse events and reports 0 with serious adverse events; it also lists 0 with other adverse events and 0 deaths. These entries describe the posted safety counts, not the unreported primary endpoint result. The registry record does not state the adverse-event observation period or provide further detail about collection and attribution.
The study is marked completed, but completion status does not substitute for outcome reporting. With no analysis results listed, the posted record supports a description of study design, endpoint definition, criterion, and safety counts. It does not support a numerical conclusion about primary endpoint performance or a comparative treatment effect.
9. Statistical Methods Explained
The registry describes a binary participant-level primary outcome: successful termination of life-threatening VT or VF after a single shock. The outcome is expressed as a count of participants. For a binary endpoint, the underlying information is whether each participant meets the success definition. An estimate of the success proportion would ordinarily require both the number meeting the definition and the number assessed. The registry record does not report the endpoint count or its analysis denominator, so neither an observed proportion nor its uncertainty can be recovered from the posted results.
What does the confidence bound mean?
A confidence interval expresses uncertainty about an estimate using a method with stated coverage properties over repeated use. A lower confidence bound is the lower endpoint of that interval. The registry’s decision rule focuses on whether this lower bound exceeds the performance goal of 62%, rather than relying only on whether the point estimate is above the goal. This makes the criterion sensitive both to the estimated success rate and to its precision. With a small amount of information, uncertainty can be substantial, although the size of uncertainty in this study cannot be determined without the endpoint result and analysis details.
The record specifies a one-sided exact lower 97.4% confidence bound. One-sided means the stated decision rule focuses on a lower limit rather than a two-sided interval with both lower and upper limits. Exact methods for a binary outcome use the discrete nature of counts rather than relying solely on a normal approximation. The registry record does not identify the particular exact procedure beyond describing the bound as exact, so a more specific method should not be assumed.
How should the performance goal be read?
The performance goal is 62%. The stated criterion is that the lower confidence limit exceed this goal. This is a threshold-based assessment: the question is whether the uncertainty-aware lower limit clears the target. The record also says the assessment occurs at one of three testing points. It does not report the observed result at any point, identify the points, or state how testing across them was operationalized. The stated criterion therefore describes the planned decision rule but cannot be used to infer the study’s result.
Why does the design matter for interpretation?
The study is listed as single group, open label, and without a randomized comparison. A single-group outcome estimate, if reported, would characterize the participants assessed with the device. It would not directly quantify a contrast with a separate control group. Open-label describes the masking status as NONE; the registry does not provide further information about who knew the device assignment or how outcome assessment was conducted. General statistical interpretation should therefore distinguish an outcome rate within a study group from a comparative treatment effect.
For a binary endpoint, over-dispersion is not the central concern in the way it can be for event counts measured repeatedly or with a variance larger than a model expects. The key statistical inputs are the number of participants meeting the definition, the number assessed, and the method used to calculate uncertainty. Neither the numerator nor the endpoint analysis denominator is reported in the registry record. No model-based endpoint analysis or adjusted result is listed.
What cannot be inferred from the posted analysis?
The registry lists no analysis results. It is therefore not possible to verify the endpoint estimate, confidence limit, criterion outcome, handling of missing endpoint measurements, or membership of the analysis population. The sample-size justification and statistical analysis plan are not reported in the registry record. There is also no basis for inferring interim analyses or other decision rules beyond the endpoint description.
General sample-size calculations are planning tools: they describe how much information might be needed under specified assumptions. They are not observed power after a study has been completed. No trial-specific sample-size justification is reported in the registry record, and the absent endpoint result cannot be replaced by a planning calculation. In particular, a sample-size illustration cannot establish whether the study had a particular probability of detecting its intended result or whether the performance criterion was met.
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 |
|---|---|---|---|---|---|---|
| Treatment | 18 | 16 | 88.9% | 65.3% to 98.6% | 67.2% to 96.9% | 66.9% to 96.6% |
R code and output
arm <- c("Treatment")
n <- c(18)
events <- c(16)
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 Treatment 18 16 88.9 65.3 98.6 67.2 96.9 66.9 96.611. Multiplicity, Missing Data and Analysis Populations
The primary endpoint description refers to a one-sided exact lower 97.4% confidence bound evaluated at one of three testing points. This wording signals that more than one testing point was part of the stated criterion. Testing at multiple points can raise a multiplicity question: when several opportunities are used to support a conclusion, the overall chance of a false-positive conclusion may differ from the chance at a single test. The registry record does not explain how the three points were defined or how the stated confidence level accounts for that testing structure. No further multiplicity adjustment details are reported in the registry record.
The registry lists no analysis results. It does not report the endpoint count or denominator, the number of participants with an evaluable endpoint, or the handling of missing endpoint data. The approach to withdrawals, protocol deviations, or participants who could not be assessed is also not reported in the registry record. Without those details, it is not possible to determine whether the endpoint analysis included all enrolled participants or a different analysis population.
The record does not identify an intention-to-treat population, a per-protocol population, or another analysis set. It also does not report whether analysis populations differed between the primary endpoint and safety outcomes. These are material reporting details because the population included in an analysis defines what its estimate describes.
The study is marked completed, but the registry does not provide an interim-analysis plan, stopping rules, or a detailed statistical analysis plan. Their existence or absence cannot be inferred from the posted record. The registry identifies the endpoint criterion and reports safety counts, but these do not fill in the missing information about multiplicity handling, missing data, or analysis populations.
12. 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 |
|---|---|---|---|
| Treatment | 0 | 18 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Treatment | 0 of 18 |
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 |
|---|---|
| Treatment | 0 of 18 |
The registry lists 18 participants at risk for serious adverse events and reports 0 participants with serious adverse events. It also lists 18 at risk for other adverse events and reports 0 participants with other adverse events. The death count is 0. These are the posted safety figures for the Treatment group.
These counts should be read as registry-reported observations, not as proof that no adverse event could occur. The record does not describe the duration of safety observation, the methods used to collect events, or how events were classified and attributed. It also does not provide a list of serious adverse-event terms; no top serious terms are listed. The zero counts therefore describe what the registry reports for this group, while the completeness and context of surveillance are not reported in the registry record.
Safety counts are distinct from the primary endpoint. The registry’s primary endpoint concerns successful single-shock termination of life-threatening VT or VF, but that result is not reported. The safety entries do not establish the primary endpoint outcome, and they do not provide a comparison with another group. Because the study is single group, these figures are descriptive rather than a randomized estimate of relative safety.
13. What the Result Does, and Does Not, Mean
The record establishes that the Jewel Electrophysiology (EP) Lab Study was a completed, open-label, single-group evaluation of the Jewel Patch Wearable Cardioverter Defibrillator. It defines a primary endpoint based on successful termination of life-threatening VT or VF after a single shock and states a performance criterion: the lower limit of a one-sided exact 97.4% confidence bound must exceed 62% at one of three testing points. These details explain what the study set out to assess and how the stated criterion was framed.
The record does not report the observed primary endpoint count, its denominator, or the confidence bound. It therefore does not show whether the criterion was met. A completed study status does not provide the missing estimate, and the endpoint definition is not itself evidence of an observed outcome. The posted safety figures report 0 serious adverse events among 18 at risk, 0 other adverse events among 18 at risk, and 0 deaths, but the registry does not give further details about safety observation or collection.
Even with a reported single-group endpoint estimate, this design would describe the outcome in the participants assessed rather than provide a randomized comparison. The registry lists no comparator group. Accordingly, a result from this study alone would not quantify a difference versus another treatment or device, and it would not isolate the device’s effect from all other influences on outcomes.
General statistical interpretation also depends on the analysis population, handling of missing endpoint data, and multiplicity procedures. Those details are not reported in the registry record. The most defensible reading is therefore limited: the record describes the study design, endpoint, decision criterion, and listed safety counts, but does not report the primary result needed to judge performance against the stated goal or support a comparative conclusion.
14. Why This Trial Matters Statistically
This study is statistically notable because it uses a threshold-based endpoint criterion rather than presenting a result as a simple comparison between treatment groups. The stated question is whether a lower confidence limit exceeds a performance goal of 62%. That framing emphasizes uncertainty as part of the decision: an estimate alone would not be sufficient to assess the criterion without its lower bound.
The endpoint is also directly tied to a specific immediate device response: successful termination of life-threatening VT or VF with a single shock. Defining the outcome and its timeframe helps clarify what the measure represents. It is a participant-level binary outcome, not a measure of repeated events, longer-term outcomes, or relative effects against a comparator.
The record also illustrates why study design and reporting need to be read together. A single-group, open-label study can describe outcomes in the enrolled group, but it does not provide a randomized between-group comparison. In addition, the registry gives the decision rule but not the observed primary result. The method cannot be evaluated from its description alone; readers need the count, analysis denominator, and confidence bound to assess the reported criterion.
The reference to testing at one of three points raises a further statistical reporting issue. Multiple testing points can affect how uncertainty and decision thresholds should be interpreted. The record states the one-sided exact lower 97.4% bound but does not explain the testing-point structure or its multiplicity handling. This makes the distinction between a stated criterion and a fully reported analysis especially important.
For researchers and clinical readers, the central statistical lesson is that endpoint definitions, confidence procedures, and transparent reporting are all needed to interpret a performance claim. The available registry entries support a clear description of the intended assessment, but they do not supply the primary estimate required to judge its outcome.
15. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for interpreting this specific record is that it does not report the primary endpoint result. The observed number of successful single-shock terminations, the analyzed denominator, and the lower confidence bound are not reported in the registry record. As a result, the stated criterion cannot be evaluated from the posted results.
The study is single group and open label, with no randomized comparator identified. This design does not support a direct estimate of comparative effect. The registry record also does not provide detailed eligibility criteria, recruitment procedures, participant characteristics, or the circumstances under which device shocks and endpoint assessments occurred. These details would be needed to understand how broadly the study group represents the intended clinical population.
Several analysis details are missing. The record does not report analysis populations, endpoint missing-data handling, protocol deviations, or the statistical analysis plan. Although it specifies an exact lower confidence bound and refers to one of three testing points, further information about those points and multiplicity handling is not reported in the registry record. The sample-size justification and any interim-analysis details are also not reported.
Safety information is limited to the listed counts: 0 serious adverse events among 18 at risk, 0 other adverse events among 18 at risk, and 0 deaths. The safety observation period, collection procedures, and additional event details are not reported in the registry record. These limitations do not change the recorded counts, but they constrain how fully those counts can be interpreted.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Jewel Electrophysiology (EP) Lab Study — NCT05490459.
- Registry record last updated 2026-04-27; status last verified 2025-05.
- Results first posted 2025-01-06.
- 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.
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19. Record Summary
The Jewel Electrophysiology (EP) Lab Study (NCT05490459) is listed as a completed, single-group, open-label device study sponsored by Element Science, Inc. It enrolled 18 participants and evaluated the Jewel Patch Wearable Cardioverter Defibrillator in adult cardiac patients. The registry lists sudden cardiac arrest as the condition. The study began on 2018-11-27 and reached primary completion on 2021-10-07.
The primary endpoint counts participants with successful single-shock termination of life-threatening VT or VF immediately following device defibrillation. The stated criterion is that a one-sided exact lower 97.4% confidence bound exceed 62% at one of three testing points. The observed endpoint count, denominator, confidence bound, and criterion outcome are not reported in the registry record.
The registry reports 0 serious adverse events among 18 at risk, 0 other adverse events among 18 at risk, and 0 deaths. No randomized comparator is listed, and no analysis results are reported.