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 DyeVert™ Plus Contrast Reduction System Multicenter Observational Study (NCT03715452), a registered phase not stated study. The primary outcome is Percentage of Contrast Media Volume Saved.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03715452 |
| Phase | Phase not stated |
| Condition | Chronic Kidney Disease |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 114 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Osprey Medical, Inc |
| Results posted | Yes |
2. Clinical Question
Population
The registry lists chronic kidney disease as the condition and records enrollment of 114 participants. It describes coronary angiography or percutaneous coronary interventional procedures, but does not report further eligibility criteria or participant characteristics in the record.
Intervention
The intervention was the DyeVert Plus Contrast Reduction System, a device described in the registry as designed to reduce contrast media volume delivered during angiography and permit real-time monitoring of contrast media volume. The registry describes the device as FDA-cleared.
Comparator
No comparator group is described. The study is identified as single arm and observational, rather than a randomized comparison. Details of allocation are not reported in the registry record.
Primary question
The primary endpoint was the percentage of contrast media volume saved, as reported on the DyeVert Plus display at the end of each case. The registry specifies measurement during the coronary angiography or PCI procedure. The numerical mean and 95% confidence interval for this endpoint are not reported in the registry record.
In statistical terms, this is a descriptive question about the device-reported percentage saved during procedures in which the system was used. Because no control group is described, the study record does not set out a direct comparison with procedures performed without the device. The endpoint definition also does not by itself establish how the observed display value relates to a counterfactual contrast volume for the same procedure. The available record therefore supports describing the study question and its measurement, but not estimating a comparative treatment effect.
3. Trial Design
NCT03715452 is titled “DyeVert™ Plus Contrast Reduction System Multicenter Observational Study.” The registry describes it as prospective, single arm, multicenter, and observational. It lists Osprey Medical, Inc as sponsor, an enrollment of 114, and a completed status. The recorded study start is 2017-07-01, and the primary completion date is 2018-01-31.
The intervention is the DyeVert Plus Contrast Reduction System. The registry summary describes the device as designed to reduce the volume of contrast media delivered during angiography while permitting real-time monitoring of contrast media volume. Chronic kidney disease is the listed condition. The procedure context for the primary endpoint is coronary angiography or PCI.
A single-arm observational design describes outcomes in a group using the system; it does not supply a concurrent control group for estimating what would have occurred without the device. The record does not describe random assignment, and allocation details are not reported in the registry record. Thus, any percentage saved reported for the intervention group would be a descriptive observation under the endpoint definition, not a randomized between-group contrast.
The registry lists two outcome measures and no analyses. It identifies evaluation of adverse events through discharge from the index procedure as a secondary outcome. The primary outcome is the percentage of contrast media volume saved per procedure, reported by the device display at the end of the case. The number of participants enrolled is recorded, but the number included in each outcome analysis and the handling of procedures or participants without endpoint data are not reported in the registry record.
The registry does not report a protocol rationale, sample-size justification, interim analyses, or a detailed statistical analysis plan. It also does not report detailed participant eligibility, baseline characteristics, or the number of participating centers. These omissions limit interpretation of how the enrolled group was assembled and how endpoint observations were handled.
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 | DyeVert™ Plus Contrast Reduction System |
|---|---|
| STARTED | 114 |
| COMPLETED | 114 |
| NOT COMPLETED | 0 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | DyeVert™ Plus Contrast Reduction System |
|---|---|---|
| Participants analysed | 114 | |
| Age, Continuous | years | 72 (SD 9) |
| Sex: Female, Male: Female | Participants | 32 |
| Sex: Female, Male: Male | Participants | 82 |
| Race/Ethnicity, Customized: Race – Caucasian | Participants | 86 |
| Race/Ethnicity, Customized: Race – African American | Participants | 25 |
| Race/Ethnicity, Customized: Race – Other | Participants | 3 |
| Region of Enrollment: United States | Participants | 114 |
| Estimated glomerular filtration rate (eGFR) | mL/min/1.73m2 | 43 (SD 11) |
| Serum creatinine (mg/dL) | mg/dL | 1.6 (SD 0.5) |
| Body mass index (BMI) | kg/m2 | 29 (SD 5) |
| Comorbidities: Hypertension | participants | 110 |
| Comorbidities: Coronary artery disease | participants | 86 |
| Comorbidities: Prior PCI | participants | 60 |
| Comorbidities: Diabetes | participants | 60 |
| Comorbidities: Congestive heart failure | participants | 54 |
| Comorbidities: Prior myocardial infarction | participants | 39 |
| Comorbidities: Anemia | participants | 33 |
| Comorbidities: Angina | participants | 30 |
| Procedure type: CAG only | Participants | 74 |
| Procedure type: CAG+PCI | Participants | 30 |
| Procedure type: PCI only | Participants | 10 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Contrast Media Volume Saved, measured over At the time of the coronary angiography (CAG) or percutaneous coronary interventional (PCI) procedure.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | % CMV savings per procedure |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is titled “Percentage of Contrast Media Volume Saved.” Its unit is percentage contrast media volume savings per procedure, and the registry identifies the parameter as a mean with a 95% confidence interval. The measurement is made at the time of coronary angiography or PCI. More specifically, the endpoint is the percentage of contrast media volume saved, or diverted, over the total procedure, as reported on the DyeVert Plus display at the end of each case.
This endpoint is used to summarize the device-reported contrast volume savings across procedures. A mean expresses the average of the measured percentages in the analyzed set, while the confidence interval describes statistical uncertainty around that estimated mean. The interval does not describe the range of values among individual procedures; it addresses uncertainty in the estimate of the group mean under the analysis assumptions.
The operational definition matters: the recorded measure comes from the device display. The registry record does not report a separate measurement method, a comparison with a control group, or a validation analysis for the display-based endpoint. Nor does it report the numerical mean or confidence interval. Consequently, the endpoint definition clarifies what was intended to be summarized, but the record does not provide the result needed to assess its magnitude or precision.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry identifies the primary endpoint and the form in which it was intended to be summarized: a mean percentage of contrast media volume saved per procedure, with a 95% confidence interval. However, the numerical mean and interval are not reported in the registry record. Without those estimates, the magnitude of the device-reported savings and the statistical precision of the mean cannot be assessed from this record.
The study is described as prospective, multicenter, observational, and single arm. These design features frame what the primary endpoint can establish. In a single-arm study, the observed endpoint describes the intervention group; there is no registry-described concurrent comparator against which to estimate a difference. A percentage recorded during use of the device should therefore not be interpreted as a randomized estimate of what the same procedures would have used without it. The study record does not give such a counterfactual comparison.
Even a reported mean and confidence interval would answer a limited question: what average percentage did the endpoint measurement indicate in the analyzed procedures, and how uncertain is that average under the chosen analysis? It would not, by itself, show how consistently individual procedures achieved savings. A mean can conceal variation, and the registry record does not provide a distribution of procedure-level values. The number of observations contributing to the primary endpoint is also not reported, so the enrolled total cannot be assumed to be the analysis denominator.
The registry lists 114 enrolled participants, but enrollment alone does not establish that all 114 contributed a primary outcome. The analysis population, missing endpoint handling, and any exclusions from the primary analysis are not reported in the registry record. These details are important because the estimated mean and its confidence interval depend on which observations were included and how incomplete measurements were treated.
The status is completed, but completion status does not substitute for outcome reporting. The registry also lists no analyses. No primary endpoint p-value, adjusted analysis, subgroup result, or comparison estimate is reported in the registry record. As a result, there is no statistical test in the record from which to infer evidence against a null hypothesis.
The posted safety counts are descriptive and belong to a secondary outcome described as evaluation of adverse events through discharge from the index procedure. They do not change the absence of a reported primary endpoint estimate. Taken together, the record permits a clear description of the study question, design, and recorded safety counts, but does not permit a quantitative interpretation of the primary endpoint result.
9. Statistical Methods Explained
The registry identifies the primary endpoint as a continuous measure summarized by a mean and a 95% confidence interval. These choices address different aspects of the result. The mean is a measure of the center of the observed procedure-level percentages. The confidence interval expresses uncertainty about the estimated mean, given the observed data and the statistical assumptions used to calculate it. It is not a range intended to contain most individual procedure values. The numerical mean and interval are not reported in the registry record, so their magnitude and precision cannot be interpreted.
What a mean describes
For a continuous endpoint, a mean combines the measured values into a single average. In this study, the intended observations are percentage contrast media volume savings per procedure, based on the value reported by the DyeVert Plus display at the end of each case. A mean can be useful for summarizing an overall level, but it does not show the spread or shape of the procedure-level measurements. Two groups of observations can have the same mean while differing in variability or in the presence of unusually high or low values. The registry record does not provide such distributional details.
What a confidence interval describes
A confidence interval gives a range of values compatible with the data under the method used to construct it. Its width reflects statistical precision: narrower intervals indicate more precise estimates under the same framework, while wider intervals indicate greater uncertainty. The stated confidence level is 95%. This does not mean that 95% of individual procedure values fall within the interval, and it does not eliminate uncertainty about design, measurement, or selection. Since the interval itself is not reported in the registry record, no judgment about its width is possible.
What the design permits
In general, an observational single-arm study estimates or describes outcomes among the participants who received the intervention. Without a comparator group, it does not directly estimate a between-group difference. Factors associated with the participants, procedures, or care setting may also relate to the observed outcome. The registry describes this study as prospective and multicenter, but does not report details that would allow those influences to be evaluated. The endpoint should therefore be read as a device-reported descriptive measure, not as a randomized comparative effect.
Analysis details that are absent
The registry reports two outcome measures and zero analyses. A detailed statistical analysis plan, the primary analysis population, the number of observations contributing to the primary endpoint, and the treatment of missing endpoint values are not reported in the registry record. Those details matter because an analysis result depends not only on the endpoint definition but also on the observations included and the method applied. The registry also does not report interim analyses or a sample-size justification, so neither should be inferred.
Planning illustrations are not observed power
Any sample-size illustration associated with this record is described as a planning calculation based on a stated fraction of an observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. Such an illustration is not the study's own design justification and is not observed power. Its hypothetical two-arm setup also differs from the registry's single-arm observational design. The numerical observed effect and planning values are not reported in the registry record, so no numerical planning interpretation can be made.
In general, planning calculations ask how many participants per arm might be needed under specified assumptions about an effect and analysis. They are conditional on those assumptions, rather than evidence that an enrolled study had a particular probability of detecting an effect. For a single-arm study without a comparator, a two-arm planning illustration does not turn the observed study into a comparative trial. It should be understood only as a hypothetical planning exercise.
What can be concluded from the posted record
The endpoint definition and summary type are reported, but its numerical result is not. No reported analysis can be checked against an alternative calculation, and no inferential result can be described. Statistical interpretation must therefore distinguish the planned descriptive summary from an actually reported estimate: the record states that the endpoint was to be summarized as a mean with a 95% confidence interval, but the mean and interval are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists two outcome measures: the primary percentage of contrast media volume saved and a secondary evaluation of adverse events through discharge from the index procedure. It reports no analyses. A multiplicity strategy, including whether any adjustment was planned for evaluating more than one outcome, is not reported in the registry record. Because no analysis results are reported, there is no basis for describing how multiple statistical tests were handled or for interpreting a family of p-values.
The primary outcome is defined per procedure, while the registry also records enrollment by participant. The number of participants or procedures included in the endpoint analysis is not reported in the registry record. The primary endpoint population, any analysis exclusions, and the handling of repeated procedures or other dependence among observations are likewise not reported. No assumptions about those features should be inferred from the enrollment total.
Missing-data methods are not reported in the registry record. The record does not state whether endpoint data were incomplete, how incomplete observations were treated, or whether any sensitivity analysis was conducted. Absence of a missing-data description does not establish that data were missing, nor does it establish that every enrolled participant contributed an endpoint measurement.
For adverse events, the registry reports counts at risk and affected, but does not describe an adjustment for exposure duration or other analysis details. The outcome timeframe is through discharge from the index procedure. Definitions beyond the listed categories and further details of event ascertainment are not reported in the registry record. These reporting gaps limit assessment of multiplicity, analysis populations, and the potential influence of incomplete observations.
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 |
|---|---|---|---|
| DyeVert Plus Contrast Reduction System | 0 | 114 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| DyeVert Plus Contrast Reduction System | 0 of 114 |
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 |
|---|---|
| DyeVert Plus Contrast Reduction System | 11 of 114 |
Most frequent non-serious adverse event terms
| Event term | Organ system | DyeVert Plus Contrast Reduction System |
|---|---|---|
| Acute Kidney Injury | Renal and urinary disorders | 11 of 114 |
| DyeVert Plus System-Related Events | Product Issues | 0 of 114 |
| Contrast-Related Anaphylactic Shock | Immune system disorders | 0 of 114 |
The registry lists a secondary outcome of evaluating adverse events through discharge from the index procedure. For the DyeVert Plus Contrast Reduction System group, 114 participants are recorded as at risk for serious adverse events, with 0 affected. The record also lists 114 at risk for other adverse events, with 11 affected, and 0 deaths. These are counts as reported in the registry, not estimates from a comparative safety analysis.
The serious adverse event count describes what was recorded in the study group during the stated outcome timeframe. With no comparator group described, the counts do not establish whether event occurrence differed from what would have been observed under another approach. The registry does not report serious adverse event terms, so the specific events in that category cannot be described. The record also does not provide a statistical comparison or an analysis accounting for exposure time.
The other adverse event count is a separate category from the serious adverse event count. The registry reports 11 affected among 114 at risk for that category. It does not provide event terms or further detail about event severity in the registry record. The death count is reported as 0. These counts should be read as descriptive registry entries for the specified group and timeframe, not as evidence of a causal relationship or a comparative risk estimate.
12. What the Result Does, and Does Not, Mean
The record establishes that a prospective, multicenter, single-arm observational study of the DyeVert Plus Contrast Reduction System was completed, with 114 participants enrolled. It defines the primary endpoint as the percentage of contrast media volume saved per procedure, as reported on the system display at the end of coronary angiography or PCI. It also records adverse event counts through discharge from the index procedure.
What the record does not establish is the numerical size or precision of the primary endpoint result. The mean percentage and its 95% confidence interval are not reported in the registry record. Without them, the result cannot be assessed for magnitude, uncertainty, or consistency with a particular numerical interpretation. The number of observations contributing to the primary endpoint is also not reported.
The single-arm observational design does not provide a randomized comparison with an untreated or alternative group. Accordingly, the design as recorded does not estimate a comparative effect. Even if a descriptive percentage were available, it would need to be interpreted according to its device-display definition and the procedures included in the analysis; it would not, on its own, establish what contrast volume would have been used in the same procedures without the system.
The reported safety counts describe events in the study group and the stated follow-up period. They are not comparative risk estimates. The registry does not report detailed event terms, an analysis plan, missing-data handling, or a primary endpoint analysis population. Those gaps constrain interpretation of both the endpoint and safety information.
The most defensible reading is therefore limited: the registry documents the study's design, endpoint definition, enrollment, status, and selected safety counts, but does not report the primary numerical outcome or a comparative analysis. The record supports describing what was measured and how the study was structured, not drawing conclusions about a treatment effect.
13. Why This Trial Matters Statistically
This study is statistically informative as an example of the difference between defining an endpoint and reporting an endpoint result. The registry specifies a continuous primary measure, its unit, its summary as a mean, and a 95% confidence interval. Those details identify the intended descriptive estimand and the form of uncertainty reporting. Yet without the estimate and interval, readers cannot judge the observed magnitude or precision. A clear endpoint definition is necessary for interpretation, but it cannot substitute for a reported result.
The design also illustrates why study structure governs the claims that can be supported. A prospective, multicenter observational study can describe measurements collected during device use, but a single-arm record has no concurrent comparator. The distinction is important because an outcome observed in an intervention group is not automatically an estimate of the difference attributable to the intervention. The registry's design description must shape interpretation even when an endpoint is framed as a percentage saved.
Another statistical issue is the difference between enrollment and analysis population. The record gives an enrollment total of 114, but does not report how many observations contributed to the primary endpoint. Readers need analysis denominators and missing-data methods to understand the effective evidence behind a mean and its confidence interval. Without those details, enrollment alone cannot establish endpoint completeness or precision.
Finally, the record separates a primary continuous outcome from a secondary adverse-event outcome, while listing no analyses. The absence of reported analyses and multiplicity methods means statistical inferences cannot be reconstructed from the registry record. The study therefore highlights the value of complete reporting: endpoint estimates, uncertainty, analysis populations, and methods are all needed for readers to assess the strength and limits of the evidence.
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 numerical primary endpoint result is not reported in the registry record. Although the endpoint is defined as a mean percentage with a 95% confidence interval, neither the mean nor its interval is available for interpretation. The record also does not state how many participants or procedures contributed to that endpoint.
The study is described as single arm and observational. No randomized comparator is described, so the record does not support a direct between-group comparison. The registry does not provide allocation details, and does not report participant characteristics beyond chronic kidney disease as the listed condition. Eligibility criteria and the number of participating centers are also not reported in the registry record, limiting assessment of the enrolled population and setting.
The primary endpoint is based on the percentage reported by the DyeVert Plus display at the end of each case. The registry record does not report additional details about endpoint validation, an independent measurement method, or how missing display readings were handled. This is a reporting limitation, not evidence that the device measurement was inaccurate.
Missing-data methods, the analysis population, statistical analysis details, and multiplicity handling are not reported in the registry record. The record also does not report a sample-size justification or interim analysis plan. Although a planning illustration is described, it is not the trial's own design justification and does not supply an observed comparative analysis. Safety reporting is limited to the listed counts; serious adverse event terms and further event details are not reported.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: DyeVert™ Plus Contrast Reduction System Multicenter Observational Study — NCT03715452.
- Registry record last updated 2020-10-19; status last verified 2020-10.
- Results first posted 2020-10-19.
- 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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18. Record Summary
NCT03715452 is a completed, prospective, multicenter, single-arm observational study sponsored by Osprey Medical, Inc. The registry records enrollment of 114 participants, a study start of 2017-07-01, and primary completion on 2018-01-31. Chronic kidney disease is the listed condition.
The intervention was the DyeVert Plus Contrast Reduction System, described as designed to reduce contrast media volume during angiography and permit real-time volume monitoring. The primary endpoint was percentage contrast media volume saved per procedure, reported by the system display at the end of coronary angiography or PCI and intended to be summarized as a mean with a 95% confidence interval.
The numerical primary endpoint estimate and confidence interval are not reported in the registry record. The registry lists adverse events through discharge from the index procedure as a secondary outcome: 0 serious adverse events among 114 at risk, 11 other adverse events among 114 at risk, and 0 deaths. No analyses are listed.