Improving Self-care of Heart Failure Caregivers: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Improving Self-care of Heart Failure Caregivers (NCT03988621), a randomized phase 2 study. The primary outcome is Change in the Health Self-Care Neglect (HSCN) Scale.

2. Clinical Question

3. Trial Design

This was a randomized, single-masked, parallel-group Phase 2 trial. The registry lists an enrollment of 343. The study summary describes caregivers being randomized 1:1 to ViCCY or a control condition. It also states that a sample of 250 caregivers, with 125 per arm, was planned to provide >90% power to detect a significant difference on the primary self-care outcome. The relationship between that planned sample and the registry’s enrollment figure is not explained in the record.

The intervention was virtual health coaching plus Internet-delivered health information. ViCCY participants received 10 coaching sessions over 6 months; the control group received health information without coaching. The coaching content was described as based on the Transactional Model of Stress and Coping and prior research. The identity of the party masked in this single-masked design is not reported in the registry record.

The primary outcome was assessed at 6 months, comparing baseline with the 6-month assessment. Data were also collected at 3, 9, and 12 months. The record says the later assessments were used to assess sustainability, but numerical results at those time points are not reported in the registry record. The stated trial start was 2019-08-23, primary completion was 2023-04-19, and the status is completed. The sponsor is the University of Pennsylvania.

The summary describes intent-to-treat analysis for the 6-month efficacy comparison. It does not report the randomization procedure, allocation concealment, or the detailed analysis model. These omissions limit how fully the design and conduct can be evaluated from the registry record.

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.

Before assignment: Enrolled caregivers were stratified by race, relationship to caregiver, and sex prior to assignment of intervention arm.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Number of participants analyzed differs across timepoints due to participant attrition, missing data due to nonresponse, and/or missed study timepoints.

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: This was a study of caregivers so the population studied reflects the 250 caregivers enrolled. In addition, as an exploratory aim, we enrolled a sample of 93 patients. The analysis of patient data was not the focus of this study so that Participant Flow focuses on caregivers.

6. Primary Endpoint

The registry lists the primary outcome as Change in the Health Self-Care Neglect (HSCN) Scale, measured over The primary outcome was analyzed at 6 months (baseline compared to 6 months) but data were collected at 9- and 12-months to assess sustainability..

The primary endpoint was change in the Health Self-Care Neglect scale score from baseline to 6 months. The scale consists of 9 yes-or-no questions, with scores ranging from 0-9. Higher scores indicate more neglect of self-care behaviors. The record identifies the measure as a continuous outcome summarized by a mean and standard deviation.

In general, a self-care measure can capture a behavior-related outcome that is relevant to an intervention aimed at supporting caregivers. Comparing change from baseline to follow-up focuses the question on how scores shifted during the trial, rather than only on the score at one assessment. That comparison is most informative when the group estimates and their uncertainty are reported, alongside the analysis population and the amount of missing follow-up data.

The registry describes the primary analysis time as 6 months and says data at 9 and 12 months were collected to assess sustainability. However, the primary group means, standard deviations, and between-group estimate are not reported in the registry record. The observed amount or direction of change therefore cannot be characterized from the posted results described in the record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes a randomized parallel-group trial with a 1:1 allocation and single masking. Randomization is generally used to reduce systematic differences between assigned groups at the start of a study. A parallel design means participants are assigned to one condition rather than moving through both conditions. The specific randomization method and allocation-concealment procedures are not reported in the registry record. The record also does not identify who was masked.

What does a change-score comparison ask?

The primary question compares change in Health Self-Care Neglect scores between baseline and 6 months across the assigned groups. In general, a change score describes how a measure differs between assessments for a participant or group. A comparison of group changes focuses on whether the pattern over time differs between the intervention and control conditions. The registry states that the primary outcome was analyzed at 6 months, but does not report the numerical group changes or the method used to estimate their contrast.

The outcome is continuous and the registry identifies the mean and standard deviation as its summary measures. In general, a mean describes the central value of a set of measurements, while a standard deviation describes how spread out the measurements are around that mean. Neither is reported for the primary outcome in the registry record. Without the group summaries or a treatment-effect estimate, the magnitude and precision of the primary comparison cannot be assessed.

What does the power statement mean?

The study summary says a sample of 250 caregivers, with 125 per arm, was planned to provide >90% power to detect significant differences on the primary outcome. In general, power is a design-stage probability of detecting an effect of a specified size under stated assumptions if that effect is present. It is not a measure of whether the trial’s observed result is true, and it is not observed power. The effect size, variability assumptions, and detailed sample-size justification are not reported in the registry record. The registry’s enrollment figure is 343; the record does not explain how that figure relates to the planned sample stated in the summary.

Any sample-size illustrations based on an observed effect are planning exercises, not a replacement for the trial’s own design justification. In general, such illustrations ask what sample size might be needed to detect a chosen fraction of an estimated effect under specified assumptions. The calculation assumptions described for these illustrations are a two-sided significance level of 0.05, equal allocation, and a normal approximation. The effect to detect is defined as a stated fraction of the observed effect. For time-to-event calculations, the output is total events; for other calculations, it is participants per arm. These assumptions do not describe a reported primary-outcome result, and they should not be interpreted as the trial’s observed power.

How should uncertainty and significance be read?

In general, a confidence interval communicates uncertainty around an estimated effect. A narrower interval indicates greater precision than a wider interval, while the interval’s location helps indicate which directions of effect remain compatible with the data. A p-value, when reported, assesses how compatible the observed data are with a specified null model under the analysis assumptions. Neither measure gives the probability that the intervention works. The registry record does not report a primary comparison estimate, confidence interval, or p-value, so these interpretations cannot be applied to the primary result.

Over-dispersion is a general concern when count data vary more than a chosen statistical model expects; using a model that accounts for extra variation can affect standard errors and uncertainty estimates. The primary endpoint is described as a continuous score, not a count outcome. The record does not state that an over-dispersion adjustment was used, nor does it report the detailed statistical model. No particular model or adjustment should therefore be inferred.

The trial summary specifies intent-to-treat analysis for the 6-month comparison. In general, an intent-to-treat analysis aims to retain participants in the groups to which they were randomized, regardless of intervention adherence. The registry does not report the operational details of that analysis, the number analyzed for the primary comparison, or how missing measurements were handled. Those details matter for judging whether the analysis as conducted matches the stated approach.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 11 outcome measures and 12 analyses. When a study evaluates multiple outcomes, time points, or statistical comparisons, the chance of at least one apparently unusual result can increase if each comparison is interpreted separately. In general, a prespecified multiplicity strategy can help control the interpretation of such results. The registry record does not report whether a multiplicity adjustment was planned or applied, how the 12 analyses relate to the listed outcomes, or which comparisons were prespecified as primary beyond identifying the 6-month self-care outcome.

The primary outcome was analyzed at 6 months, with assessments also collected at 3, 9, and 12 months. The summary says the 9- and 12-month data were collected to assess sustainability. Numerical results at those time points are not reported in the registry record. Without the analysis plan and results for the different time points, it is not possible to determine how the secondary or repeated assessments were incorporated into interpretation.

The record states that the number analyzed differs across time points because of participant attrition, missing data due to nonresponse, and/or missed study time points. This is important: the observed data may represent different analyzed populations at different assessments. The record does not report the number analyzed at each time point, the amount of missingness by group, or the reasons in enough detail to distinguish among those sources. It also does not report whether missing values were imputed, whether sensitivity analyses were conducted, or what assumptions were made about missing data.

The summary describes an intent-to-treat approach for the primary comparison, but details on its implementation are not reported in the registry record. These missing analysis details limit assessment of potential bias and of how robust any estimate would be to incomplete follow-up. Because numerical primary results are also not reported, neither multiplicity nor missing-data effects can be evaluated against the observed treatment estimate.

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 1% reporting threshold.

Most frequent serious adverse event terms

Serious events with the highest arm-level rate: heart failure (41.2%), immunology (14.3%), hemotology (11.9%), fall/fall complications (7.8%), kidney injury (5.9%).

The registry reports serious adverse event counts separately for caregiver groups and patient groups. Among caregivers, the intervention group lists 9 serious adverse events among 125 at risk, and the Health Information group lists 13 among 125 at risk. Other adverse events are listed as 0 in both caregiver groups. Deaths are listed as 0 in both caregiver groups.

Separate patient entries report 21 serious adverse events among 42 at risk in the Intervention (Patient) group and 26 among 51 at risk in the Health Information (Patient) group. Other adverse events are listed as 0 among 29 at risk in the intervention patient entry and 0 among 31 at risk in the Health Information patient entry. Deaths are listed as 15 and 12, respectively. These patient entries have different at-risk figures from the serious-event figures in their respective entries, so the listed counts should be read with their corresponding registry denominators, not combined across entries.

The record lists Heart Failure at 41.2%, Immunology at 14.3%, Hemotology at 11.9%, Fall/fall complications at 7.8%, Kidney Injury at 5.9%, and Diverticulitis at 3.9% among the top serious-event terms. The basis for these term percentages is not reported in the registry record. Counts and terms alone do not establish that an event was caused by the intervention or indicate comparative risk. Further event definitions, attribution, and analysis details are not reported.

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

The registry record establishes that a randomized comparison was conducted between virtual health coaching plus online health information and online health information alone for informal caregivers of adults with heart failure. It describes the intervention, the control condition, and the primary self-care outcome. It also reports trial enrollment and certain serious adverse event counts. These details help define what was studied.

The record does not report numerical results for the primary endpoint. It therefore does not show the average change in either group, the difference between groups, or the precision of that difference. The direction, size, and statistical uncertainty of the primary comparison cannot be determined from the registry record. The completed trial status does not fill this reporting gap.

In general, a statistically significant finding would not by itself establish the size or practical importance of an effect; a non-significant result would not establish that groups are equivalent. Both interpretations depend on the estimated effect, its uncertainty, the analysis, and the clinical context. Those primary-outcome statistics are not reported in the registry record, so neither conclusion is supported.

The registry’s planned sample and power statement describe the study’s design expectations, not its observed outcome. Similarly, serious adverse event counts should be interpreted as reported counts with their associated denominators. They do not on their own establish causation or provide a full comparative safety analysis. The listed terms and percentages also lack a reported denominator basis in the registry record.

The trial’s findings on stress, coping, health status, quality-adjusted health, or hospital and provider events cannot be characterized from the listed outcome names alone. Numerical results for those outcomes are not reported in the registry record. Accordingly, the record supports a description of the research question and design, but not a conclusion about the effects of coaching on the measured outcomes.

13. Why This Trial Matters Statistically

This trial asks a question about a supportive intervention in an identifiable caregiving context: whether adding virtual coaching to online health information changes self-care neglect scores. The randomized comparison and common health-information component provide a clear framework for studying the added coaching component. The trial also collected measures related to stress, coping, health status, and caregiver events, reflecting a broader set of questions than the primary endpoint alone.

Statistically, the record illustrates why a study’s design description and its results need to be read separately. The registry describes randomization, a planned sample, a power target, outcome timing, and an intended intent-to-treat comparison. Those details help explain what investigators planned to assess, but they cannot substitute for group estimates, uncertainty intervals, and analysis-population information. The numerical primary results are not reported in the registry record, leaving the central comparison uninterpretable in terms of effect size and precision.

The record also highlights the importance of transparent follow-up reporting. It notes that the number analyzed differs across time points because of attrition, nonresponse, and missed study time points. Reporting analyzed numbers and missing-data methods would help readers understand how much evidence informs each comparison and what assumptions underlie the estimates. With 11 outcome measures and 12 analyses listed, clear reporting of prespecified comparisons and multiplicity handling would also help readers distinguish confirmatory questions from other analyses.

These are general statistical reporting considerations, not claims about the conduct or findings of this trial. The available record is useful for identifying the research question and design, while the absent outcome estimates prevent assessment of the primary result.

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.

A central limitation of the available record is that it does not report the numerical primary-outcome results. There are no group means or standard deviations, no between-group estimate, and no confidence interval or p-value for the 6-month comparison. This prevents assessment of the effect’s direction, magnitude, and precision.

The record says the number analyzed varied across time points because of attrition, nonresponse, and/or missed study time points, but does not give the analyzed numbers by group and assessment. It also does not report missing-data methods or sensitivity analyses. Although the summary describes intent-to-treat analysis, its implementation is not detailed.

Other design and analysis information is also absent from the registry record: the identity of the masked party, the randomization and allocation-concealment procedures, and the statistical model are not reported. The summary states a planned sample of 250 caregivers, with 125 per arm, while the registry lists enrollment of 343; the record does not explain the relationship between these figures. Detailed assumptions behind the planned power statement are not reported.

The registry lists 11 outcome measures and 12 analyses but does not report a multiplicity strategy or numerical findings for the secondary outcomes. The basis for the percentages attached to serious-event terms is not reported. These limitations concern what can be evaluated from the registry record and should not be treated as evidence that an unreported analysis was or was not conducted.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Improving Self-care of Heart Failure Caregivers — NCT03988621.
• Registry record last updated 2025-02-20; status last verified 2025-02.
• Results first posted 2024-10-26.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

The record describes NCT03988621, a completed Phase 2 randomized, single-masked, parallel-group trial sponsored by the University of Pennsylvania. It studied ViCCY virtual coaching plus Internet-delivered health information versus health information alone for informal caregivers of adults with heart failure. The registry lists enrollment of 343; the study summary describes a planned sample of 250 caregivers, with 125 per arm.

The primary outcome was change in Health Self-Care Neglect scores from baseline to 6 months. Assessments were also collected at 3, 9, and 12 months. The summary describes intent-to-treat analysis for the primary comparison and notes variation in the number analyzed across time points due to attrition, nonresponse, and missed assessments.

Numerical primary and secondary outcome results are not reported in the registry record. Serious adverse event counts are listed separately for caregivers and patients, with deaths reported in the patient entries. The record does not provide the analysis detail needed to interpret those counts as comparative effects.