Use of Simulation to Improve VAD Self-management: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Use of Simulation to Improve VAD Self-management (NCT03073005), a randomized na study. The primary outcome is Comparisons of VAD-care Checklist Assessment on the Patient and Written Examination Scores Between SBML and Usual Training Groups.

2. Clinical Question

The assessment covered controller changes, power-source changes, and dressing changes, as well as a written examination. Only caregivers were assessed on dressing changes, because patients do not independently complete that task. The primary outcome was defined in terms of the percentage of checklist items correct, with performance summarized using the median and inter-quartile range.

The study also listed secondary questions about infections and re-hospitalizations up to 3 Months After VAD Implant, skill decay in five domains, and self-confidence between groups. Those questions concern different outcomes from the primary skills assessment. The registry record does not report results for the primary or secondary questions, so the comparative effects cannot be described from this record.

3. Trial Design

The study, titled “Use of Simulation to Improve VAD Self-management,” was a randomized, parallel-group trial with no masking. The registry record lists an enrollment of 143 and identifies heart failure as the condition. The study status is completed. Its recorded start date is 2017-06-01, and its primary completion date is 2019-10-30.

Participants were assigned to traditional VAD training or simulation-based VAD training. Both groups received a video produced by the VAD manufacturer. The simulation-based group also participated in simulation-based mastery learning for VAD management. The intervention is classified as “other” in the record; the record does not give further details about how randomization was generated or implemented.

The primary assessment compared group performance on VAD-care checklist tasks and a written examination. Tasks included controller change, power-source change, and dressing change. Only caregivers completed the dressing-change assessment. The primary outcome was recorded as the percentage of checklist items correct, summarized by the median and inter-quartile range, with a timeframe of 3 months.

The primary-outcome population description refers to patient-caregiver pairs in which both members completed training and assessments through discharge testing. The relationship between that inclusion description and the recorded 3-month timeframe is not explained further. The registry record does not report the number analyzed for the primary endpoint, group-specific outcome summaries, or a statistical comparison. It also does not report a detailed protocol, allocation concealment, or the procedures used to deliver or assess the training.

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: Patient and caregiver pairs were included if both the patient and their caregiver completed training and assessments through discharge testing. (\*Note- Only caregivers were assessed on dressing change as patients do not independently complete this task.)

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.

Population: in order to be considered for final analysis both the patient participant plus their caregiver (pairs) must still be enrolled in the study

6. Primary Endpoint

The registry lists the primary outcome as Comparisons of VAD-care Checklist Assessment on the Patient and Written Examination Scores Between SBML and Usual Training Groups, measured over 3 months.

The primary endpoint concerns performance during VAD care and on a written examination. Checklist performance was expressed as the percentage of checklist items correct. The assessed care activities were controller change, power-source change, and dressing change; caregivers alone were assessed on dressing change. The record also includes written examination scores in the primary-outcome title.

These assessments are intended to capture practical self-management skills as well as written knowledge. In general, an observed skills assessment can provide information about performance on the tasks included in the assessment, while an examination can capture knowledge tested by its questions. Neither measure alone necessarily represents every aspect of managing a VAD in daily life. The registry record does not describe the checklist content, examination format, scoring rules, assessor training, or validation of these measures.

The record specifies a median and inter-quartile range as the summary statistics and gives a 3-month timeframe. A median describes the middle of the observed values, while the inter-quartile range describes the spread of the central portion of the observations. These summaries can be useful when performance values are not well represented by a mean and standard deviation. This is a general statistical explanation, not a claim about the distribution in this trial.

No primary endpoint values or between-group results are reported in the registry record. Therefore, the record does not establish the magnitude, direction, or precision of any difference in checklist or examination performance.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry record describes a randomized, parallel-group comparison. In general, randomization assigns participants to study groups by chance and is intended to reduce systematic differences between groups at the point of assignment. A parallel design means the groups receive their assigned approaches during the trial rather than crossing over between approaches. These general definitions do not establish how randomization was implemented in this particular study; the sequence-generation and allocation-concealment procedures are not reported in the registry record.

What does “unmasked” mean?

The record lists masking as none. In general, masking means withholding knowledge of group assignment from participants, clinicians, assessors, or analysts, depending on the design. When participants know whether they received simulation-based training, their expectations or behavior could affect some outcomes. Assessors who know group assignment could also influence subjective ratings. The record does not specify which people assessed the checklist or examination, or whether any safeguards were used to limit assessment bias.

Why report a median and inter-quartile range?

The primary outcome is described as the percentage of checklist items correct, summarized by the median and inter-quartile range. In general, the median is the central observed value when observations are ordered. The inter-quartile range describes the spread of the middle half of the observations. These summaries can be informative when a distribution is skewed, has outlying values, or is not well described by a symmetric model. The record does not report the observed distribution, so it is not possible to tell why these summaries were selected for this trial.

Descriptive summaries and inferential comparisons answer different questions. Group medians and inter-quartile ranges describe the observed performance within each group. A between-group analysis estimates a contrast and may quantify its uncertainty. The registry record reports neither the group summaries nor the analysis result. It does not identify a statistical test, model, adjustment strategy, or confidence-interval method for the primary outcome. No recalculated comparison is available from the posted record.

What does a confidence interval tell readers?

In general, a confidence interval communicates uncertainty around an estimated effect under the assumptions of the method used. It gives more information about precision than a single point estimate alone. It does not show the probability that the true effect lies in a particular interval, and its interpretation depends on the analysis and data. There is no primary-outcome estimate or confidence interval reported in the registry record, so precision cannot be assessed for the skills comparison.

Why can missing assessments matter?

In general, missing outcome data can affect both the number of observations available and the validity of a comparison. If the reason an assessment is missing is related to group assignment or likely performance, an analysis limited to observed outcomes may not reflect all randomized participants. Statistical methods can address missingness under stated assumptions, but those assumptions and methods need to be described. The registry record does not report primary-endpoint completion by group, reasons for missing assessments, imputation, or sensitivity analyses.

The primary population description requires the patient and caregiver both to complete training and assessments through discharge testing. This condition is relevant to interpreting the population represented by an analysis, but the record does not state how many pairs fulfilled it or whether all randomized participants were analyzed according to their assigned group. The analysis population and handling of departures from the planned training are not reported.

How should enrollment planning be understood?

In general, a sample-size calculation is a planning exercise based on assumptions about the outcome, the effect worth detecting, variability, significance level, allocation, and analysis. It is not a measure of the probability that a completed study found an effect. The registry record describes a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. It states that the effect to detect is a specified fraction of the observed effect, but the record does not give the illustration's resulting sample-size values in the registry record for this explanation. Such planning figures, when displayed, should not be read as observed power or as proof that a study was adequately powered.

The registry record lists four outcome measures and no analyses. It does not report a statistical-analysis plan, interim analyses, a prespecified hierarchy of outcomes, or a method for handling multiple comparisons. Those omissions limit assessment of how the trial's intended statistical questions were translated into analyses. No additional statistical method can be inferred from the outcome descriptions alone.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists four outcome measures, including the primary skills assessment and secondary outcomes concerning infections and re-hospitalizations, skill decay in five domains, and self-confidence between groups. It reports no analyses. A statistical-analysis plan, including how the primary and secondary outcomes were prioritized, is not reported in the registry record.

Multiplicity arises when several outcomes, time points, or comparisons are tested. In general, testing many questions can increase the chance of at least one apparently unusual result even when there is no underlying effect. Researchers may address this through a prespecified hierarchy, adjustment procedures, or by treating some analyses as exploratory. The record does not state whether any such approach was planned or used. With no posted analysis results, it is not possible to assess how multiplicity affected the interpretation.

Missing-data methods are also not reported. The primary population description includes patient-caregiver pairs only if both members completed training and assessments through discharge testing. The record does not state how many pairs met this condition, how many assessments were missing, why data were missing, or whether analyses followed assigned group regardless of completion. It does not report imputation, sensitivity analyses, or an approach to incomplete follow-up. These details matter because the analyzed participants and assumptions about missing outcomes can influence a comparison.

The record does not report a prespecified statistical plan or analysis population. As a result, it is not possible to determine from the registry entry whether the posted outcome descriptions correspond to all planned analyses or to identify the intended treatment of secondary comparisons.

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 0% reporting threshold.

The adverse-event record lists patient groups for traditional VAD training and simulation-based VAD training. For the traditional-training group, it records 0 serious adverse events among 33 at risk and 0 other adverse events among 33 at risk; it also records 10 deaths. For the simulation-based group, it records 0 serious adverse events among 36 at risk and 0 other adverse events among 36 at risk; it also records 10 deaths.

These are registry counts, not estimates of a treatment effect. The record does not provide event timing, causes of death, event attribution, severity details for other events, or information about the relationship of any event to training. It does not explain how the adverse-event observation period relates to follow-up for the primary assessment. The counts should therefore be read as the events entered in the registry record, not as a complete account of safety or as evidence that either training approach caused or prevented an event.

The group counts are presented for patients, while the primary skills assessment includes patients and caregivers. These are different populations and outcomes. The record does not report caregiver adverse-event data in the listed groups.

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

The registry record establishes that the trial was designed to compare simulation-based mastery learning, added to traditional video training, with traditional video training alone for VAD self-management. It identifies practical checklist tasks and a written examination as the primary assessment and describes the summary measure and timeframe. It also lists outcomes related to infections and re-hospitalizations, skill decay, and self-confidence.

However, no primary or secondary outcome results are reported in the registry record. There are no group performance summaries, between-group estimates, confidence intervals, or p-values. It is therefore not possible to state whether performance differed between the groups, how large any difference was, or how precise an estimate would be. The design and outcome descriptions alone cannot establish that either training approach improved self-management skills, reduced infections or re-hospitalizations, or changed confidence.

Even if a future or separate report described a difference in checklist or examination performance, the endpoint would represent performance on the assessed tasks and questions, rather than every aspect of VAD management or later clinical outcomes. The record does not provide validation information for the assessment or explain how test performance relates to daily self-management. Results for skills would also not automatically establish an effect on infections or re-hospitalizations, which are separate outcomes.

The safety entries document event counts, but do not include enough context to attribute events to training or compare safety reliably. The primary population description and missing-data methods are also insufficiently detailed to evaluate who contributed outcome data. Overall, the registry record describes the trial question and design but does not provide the outcome evidence needed to answer its comparative question.

13. Why This Trial Matters Statistically

This trial raises a statistical question about how to evaluate a training approach whose intended effect is practical skill acquisition. The primary outcome combines checklist assessments of VAD-care tasks with written examination scores. Such outcomes can be informative, but interpretation depends on clear definitions of the tasks, scoring, assessment timing, and the analysis that compares groups. The registry record identifies several tasks and a summary measure, while leaving those measurement and analysis details unreported.

The patient-caregiver structure is also relevant. Both members of a pair had to complete training and assessments through discharge testing to be included in the primary population described by the record, and dressing changes were assessed only for caregivers. These design features make it important to know precisely who was analyzed for each task and how paired observations were handled. The record does not report those analysis details or the number with endpoint data.

Unmasked training comparisons can be challenging to interpret when outcomes involve observed performance. In general, the intervention may be apparent to participants, and knowledge of assignment could also affect assessment if assessors are not masked. The record lists no masking but does not state whether assessment procedures attempted to limit this concern. This is a reason to distinguish the randomized design from the information available about measurement and analysis.

Finally, the study's stated clinical aims include safety-related outcomes, while its primary outcome focuses on skills and written knowledge. These outcomes answer different questions and require separate results. Because the registry record reports no analyses, it cannot show whether the skills assessment or the secondary clinical outcomes differed by group. The trial is statistically informative as a clearly framed comparison, but the posted record does not provide results with which to quantify or interpret those comparisons.

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 main limitation for interpreting this trial from the registry record is the absence of posted outcome results. No primary endpoint summaries or between-group analyses are reported, so effect direction, magnitude, and precision cannot be assessed. The record also reports no analyses for the listed outcomes.

Important design and analysis details are not reported in the registry record. These include the randomization procedure and allocation concealment, the outcome-assessment procedures, whether assessors knew group assignment, the statistical test or model for the primary endpoint, and the analysis population. Baseline characteristics and group-specific completion of the primary assessment are also not reported.

The record's primary population description requires both members of a patient-caregiver pair to complete training and assessments through discharge testing, but does not explain how that criterion was applied to the randomized groups. It gives a 3-month primary-outcome timeframe without further detail clarifying its relationship to discharge testing. Missing assessments, reasons for missingness, and any methods used to address missing data are not reported.

The primary outcome includes checklist performance and a written examination, but the registry record does not describe the assessment instrument, scoring rules, assessor training, or validation. The record also does not provide the timing or definitions needed to interpret the separate secondary outcomes in detail. The adverse-event entries lack information on timing, attribution, and causes of death. These limitations restrict interpretation to the trial's recorded design and event counts rather than comparative conclusions about efficacy or safety.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Use of Simulation to Improve VAD Self-management — NCT03073005.
• Registry record last updated 2021-05-10; status last verified 2021-05.
• Results first posted 2021-05-10.
• 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

NCT03073005, “Use of Simulation to Improve VAD Self-management,” is recorded as a completed, randomized, parallel-group trial with no masking and an enrollment of 143. It compared traditional VAD training by manufacturer-produced video with the same video training followed by simulation-based mastery learning. The condition is heart failure.

The primary assessment concerned VAD-care checklist performance and written examination scores, with performance expressed as the percentage of checklist items correct and summarized using the median and inter-quartile range. Its recorded timeframe is 3 months. The described tasks were controller change, power-source change, and dressing change; only caregivers were assessed on dressing change.

The record lists secondary outcomes concerning infections and re-hospitalizations, skill decay, and self-confidence. It reports no analyses or primary and secondary outcome results. Adverse-event entries list zero serious and zero other events for the patient groups, along with 10 deaths in each group. The available record therefore describes the trial design and selected event counts but does not establish comparative outcome effects.