A Nurse-led Intervention to Extend the HIV Treatment Cascade for Cardiovascular Disease Prevention: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Nurse-led Intervention to Extend the HIV Treatment Cascade for Cardiovascular Disease Prevention (NCT03643705), a randomized na study. The primary outcome is Systolic Blood Pressure.

2. Clinical Question

3. Trial Design

The registry identifies this study as a randomized, single-masked, parallel trial. Participants were assigned to either the nurse intervention or the education control. The record does not identify who was masked or describe the randomization sequence, allocation concealment, or procedures used to maintain masking. The phase is listed as NA.

Enrollment is recorded as 298. The trial began on 2019-09-20, had a primary completion date of 2023-01-15, and is listed as completed. Those administrative details do not establish how many participants contributed data to the primary outcome or how many completed each measurement. The registry record does not report outcome-specific analysis populations or participant flow.

The nurse intervention was planned around in-person visits at 0, 4, 8, and 12 months, as well as telephone contact. The education control was also described as involving in-person visits at 0, 4, 8, and 12 months. The registry’s description of the nurse intervention is cut off after naming several components, so the complete intervention cannot be reconstructed from the record.

The primary outcome is systolic blood pressure, expressed as a model-estimated mean in mmHg, with a 12-month timeframe and repeated measures across the four stated time points. Non-HDL cholesterol is listed as a secondary outcome. The registry lists four outcome measures overall, but does not report their full results or a detailed statistical analysis plan.

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

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: 1 participant withdrew after randomization but before the baseline data collection occurred

6. Primary Endpoint

The registry lists the primary outcome as Systolic Blood Pressure, measured over 12 months.

Systolic blood pressure is a continuous measure of blood pressure. In this trial, it is the primary outcome and is described as a model-estimated mean in mmHg at 12 months, based on repeated measurements at 0, 4, 8, and 12 months. Repeated measurements can describe the outcome over time rather than relying only on a single recorded value. A model may also account for the relationship between measurements from the same participant, depending on the analysis method.

For this trial’s question, the relevant statistical evidence would include the estimated blood pressure in each group, the estimated between-group contrast, and its uncertainty. A confidence interval would indicate a range of values compatible with the analysis, subject to its assumptions. A point estimate alone would not show how precise the comparison is. The registry record does not report the group estimates, contrast, confidence interval, or p-value, so the primary outcome cannot be interpreted as an observed comparative result from this record.

The endpoint is a measure of blood pressure, not a direct measure of cardiovascular events. Its role in the trial is to assess a cardiovascular risk factor. The registry does not report whether additional endpoint definitions, measurement procedures, or thresholds were specified in the full protocol.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry identifies systolic blood pressure as a continuous primary outcome reported as a model-estimated mean. It also states that measurements were repeated at 0, 4, 8, and 12 months. These details indicate the type and timing of the outcome, but they do not specify the statistical model used. The analysis method, covariance structure, adjustment terms, and estimation procedure are not reported in the registry record.

What does a model-estimated mean represent?

In general, a model-estimated mean is an estimate produced by a statistical model rather than simply a raw average. The model can be constructed to account for features of the study design or to adjust for specified variables. Its interpretation depends on the model terms and assumptions. Because those details are not reported for this trial, the precise meaning of the model-estimated group values beyond the registry description is uncertain.

The registry gives the dispersion measure as standard error. In general, a standard error describes the uncertainty of an estimated quantity, such as a mean; it is not a description of the spread of individual participant measurements. A standard deviation, by contrast, describes participant-level variation around a mean. The record does not post standard errors or estimates for this outcome, so their magnitude cannot be assessed.

Why do repeated measurements matter?

In general, measurements from the same participant are related rather than independent. Repeated-measures methods account for that dependence when estimating changes over time or comparing groups across time. The choice of method and assumptions about the within-participant relationship can affect estimates and their uncertainty. The registry specifies the measurement schedule but does not report the approach used to model this dependence. It also does not say whether the primary comparison was a between-group contrast at 12 months, a contrast in change from baseline, or another model-based quantity.

A confidence interval, in general, communicates the uncertainty around an estimated effect. Its width reflects the precision of the estimate under the analysis assumptions. A p-value addresses compatibility between the observed data and a specified null hypothesis under a statistical model; it does not measure the size or importance of an effect. Neither a confidence interval nor a p-value for the primary outcome is reported in the registry record. No conclusion about statistical evidence for a difference can be drawn from the endpoint description alone.

What do the planning assumptions mean?

The record describes a planning illustration based on the observed effect. It specifies a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. In general, a sample-size calculation estimates how many participants might be needed under chosen assumptions to detect a specified effect with a chosen operating characteristic. The assumptions determine the illustration, so its output is not a guarantee about a future study or a description of what happened in this trial.

The record does not report the resulting participant-per-arm values for this illustration. It also does not report a protocol-based sample-size justification. Planning values are not observed power: observed power is not a substitute for interpreting an effect estimate and its uncertainty. A planned calculation also does not demonstrate that the enrolled or analyzed sample was adequate for the primary comparison.

What can be inferred from the analysis entries?

The registry lists zero analyses. This indicates that analysis results are not posted in the registry entry; it does not establish that no analysis was conducted outside the record. The primary outcome estimates, secondary outcome results, model details, and statistical tests are not reported. The registry lists four outcome measures in total, but does not provide enough information to reconstruct a complete analysis plan or determine which comparisons were prespecified.

In general, over-dispersion is an issue when observed variability exceeds what a statistical model assumes. It can make standard errors too small if the model does not account for the extra variability. That concern is not documented for this continuous primary endpoint, and the registry does not report a model or diagnostic assessment. It should therefore be treated only as a general statistical consideration, not as a finding about this trial.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists four outcome measures overall and identifies non-HDL cholesterol as a secondary outcome. It does not list all outcome definitions or report how many comparisons were planned. It also does not report whether the investigators adjusted for multiple outcomes, time points, or comparisons. Without an analysis plan, the effect of multiplicity on interpretation cannot be assessed. In general, testing multiple hypotheses can increase the chance of obtaining at least one apparently unusual result, so a stated strategy for prioritizing or adjusting comparisons is useful.

The primary outcome involves repeated measurements at 0, 4, 8, and 12 months, but the registry does not describe whether each time point was analyzed separately or how the 12-month endpoint was contrasted between groups. The primary outcome’s model and inferential procedure are not reported. The registry lists zero analyses, and no primary or secondary outcome estimates are posted.

Missing data handling and analysis populations are also not reported in the registry record. The entry does not state how many participants had outcome measurements at each time point, how missing measurements were handled, or whether the analysis used an intention-to-treat population or another population definition. Enrollment alone cannot answer those questions. The masking field is single, but who was masked and whether masking was maintained are not reported. These omissions limit reproducibility and make it difficult to assess potential bias or determine how closely the posted design details align with the analyses.

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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: non-study related events (17.4%), emergency room visit or hospitalization for high home blood pressure (2.0%), emergency room visit for chest pain (0.7%).

The registry lists serious adverse events for the Nurse Intervention group as 30 affected participants among 149 at risk, and for the Education Control group as 22 affected participants among 148 at risk. It lists other adverse events for 44 among 149 at risk in the Nurse Intervention group and 45 among 148 at risk in the Education Control group. Deaths are listed as 2 in each group. These entries are counts, not adjusted comparisons.

The record lists selected serious adverse-event terms and percentages: “Non-study related events” at 17.4%, “Emergency room visit or hospitalization for high home blood pressure” at 2.0%, and “Emergency room visit for chest pain” at 0.7%. The record does not report the denominator or calculation details for these percentages in the information available. The listed terms should therefore be read as registry descriptions, not as a complete event profile.

The registry does not report event definitions, duration of follow-up for safety, attribution to the intervention, severity criteria, or statistical comparisons. Counts alone do not establish causation or show whether a difference between groups is meaningful. These safety entries should be interpreted descriptively and alongside the missing methodological details.

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

The record describes a randomized, parallel comparison of a nurse-led intervention with general prevention education among people living with HIV receiving suppressive antiretroviral therapy. It identifies systolic blood pressure at 12 months as the primary outcome and gives the repeated measurement schedule. It also provides selected safety counts and describes a secondary outcome of non-HDL cholesterol.

It does not report the primary outcome results. In particular, the group estimates, between-group contrast, confidence interval, and p-value are absent. The record therefore does not show whether systolic blood pressure differed between groups, how large any difference was, or how precisely it was estimated. The trial’s stated aim is not itself an outcome result, and the description of an intervention does not demonstrate its effect.

The design information can help readers understand the intended comparison, but important implementation and analysis details are absent. The record does not report who was masked, the complete nurse intervention description, the statistical model, missing-data methods, analysis populations, or multiplicity strategy. It lists four outcome measures and zero analyses. These omissions prevent a full statistical appraisal of the study results from the registry entry.

The safety counts describe reported events by group, but the record does not provide enough context to determine attribution or compare event risk. The planning assumptions are intended for a sample-size illustration and do not constitute evidence of observed power or an outcome effect. Overall, the registry supports a limited description of trial structure and selected safety information, not a conclusion about the comparative primary outcome.

13. Why This Trial Matters Statistically

Statistically, this trial addresses a practical question about extending cardiovascular prevention within HIV specialty care. The randomized parallel design is relevant because it sets up a comparison between a nurse-led approach and general prevention education. The repeated systolic blood pressure measurements also make the time dimension part of the outcome description, rather than defining the primary endpoint as a single isolated reading.

The record illustrates why design information and result information need to be read separately. It describes enrollment, interventions, measurement timing, and selected safety counts, but does not post the primary outcome analysis. Without an effect estimate and uncertainty interval, readers cannot assess the magnitude or precision of the central comparison. The absence of posted analyses also limits assessment of how the repeated measurements were handled.

Several features are important for statistical interpretation: the primary endpoint is continuous, measurements are repeated within participants, and the entry identifies other outcome measures. In general, these features call for clear reporting of the model, analysis population, handling of missing observations, and approach to multiple comparisons. Those details are not reported in the registry record. Their absence is consequential for reproducibility, even when the broad design and outcome schedule are described.

The safety entries also show why counts require context. Event definitions, follow-up, attribution, and comparative analyses affect what can be inferred from group counts. The registry’s entries are useful descriptive information, but they cannot independently establish causation or a treatment effect. Thus, the statistical importance of the record lies in clarifying the intended question and in identifying which information is needed to evaluate it fully.

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 registry record does not include results for the primary outcome or the secondary outcome. It reports no analyses, so there is no effect estimate, confidence interval, p-value, or model output to evaluate. This is the main limitation for interpreting the trial’s comparative findings.

The intervention description is incomplete: it lists nurse-led care coordination, medication protocols and adherence support, and home blood pressure monitoring, then cuts off while describing another component. The record therefore does not give a complete account of the nurse intervention. It also does not report who was masked, details of allocation concealment, or how randomization was implemented.

The registry identifies repeated measurements at 0, 4, 8, and 12 months but does not report the statistical model, covariate adjustments, missing-data approach, analysis population, or participant numbers contributing data at each time point. It lists four outcome measures but does not describe a multiplicity strategy or provide a full set of outcome definitions. These gaps limit reproducibility and make it difficult to assess analytic choices.

Safety information is also limited. The record gives counts and selected event terms, but does not report event definitions, attribution, or a statistical comparison. It does not provide the denominator details for the listed event-term percentages in the available record. Finally, enrollment is listed as 298, but the number analyzed for the primary outcome is not reported. These limitations are specific to what the registry record documents and do not establish what information may appear in other study materials.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Nurse-led Intervention to Extend the HIV Treatment Cascade for Cardiovascular Disease Prevention — NCT03643705.
• Registry record last updated 2024-10-16; status last verified 2024-09.
• Results first posted 2024-04-23.
• 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

NCT03643705 is listed as a completed randomized, single-masked, parallel trial sponsored by Case Western Reserve University. Enrollment is recorded as 298, with a start date of 2019-09-20 and primary completion date of 2023-01-15. The trial compares a multi-component nurse intervention with general prevention education among people living with HIV receiving suppressive antiretroviral therapy.

The primary outcome is model-estimated mean systolic blood pressure in mmHg at 12 months, with repeated measurements at 0, 4, 8, and 12 months. Non-HDL cholesterol is listed as a secondary outcome. The registry record does not report outcome analyses or primary outcome estimates. It also does not report the complete nurse intervention description, statistical model, missing-data methods, analysis populations, or multiplicity strategy.

Serious and other adverse-event counts and deaths are listed by group, along with selected serious-event terms. These entries are descriptive; the record does not provide enough detail to assess attribution or comparative risk.