A Virtual Cardiometabolic Health Program for African Immigrants: The Afro-DPP Program: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for A Virtual Cardiometabolic Health Program for African Immigrants: The Afro-DPP Program (NCT05144737), a randomized na study. The primary outcome is Change in Diastolic Blood Pressure (mm/Hg) Over a 6-month Period.

2. Clinical Question

This question is relevant to a program intended to address several cardiometabolic risk factors, but the posted primary result concerns diastolic blood pressure only. It does not by itself describe changes in body composition, other blood pressure measures, or the other risks named in the study description. The registry record lists five outcome measures, but secondary results are not posted. The clinical question should therefore be read narrowly: it concerns the observed six-month blood pressure changes in the two intervention sequences, not the full range of potential program outcomes.

3. Trial Design

The study is listed as randomized, unmasked, and crossover, with an enrollment of 60. The study description says that two African churches were randomly assigned to an immediate intervention or delayed intervention group and calls the design a non-equivalent control group design. It describes the delayed group as receiving the program after the initial 6-month period. These labels and the description do not fully clarify how the registry’s crossover designation relates to the church-level assignment and intervention sequence.

The immediate group was scheduled to begin 6 months of an adapted lifestyle intervention with a Lifestyle Coach, alongside remote monitoring, followed by a 6-month observation period. The delayed group was scheduled to have remote monitoring without a Lifestyle Coach for the first 6 months, followed by the intervention. The primary outcome timeframe is baseline and 6 months, so the posted primary result pertains to the initial period rather than a reported comparison across both sequences.

All participants were to receive a Bluetooth-enabled digital scale and blood pressure monitor and use the Omron Connect app to sync readings. The record says the research team would access those readings to monitor outcomes and progress. The sponsor is Johns Hopkins University. The study is marked completed, with a start date of 2021-11-21 and primary completion date of 2024-08-16.

The posted primary endpoint summaries include 20 participants in the immediate group and 23 in the delayed group. The reason these endpoint counts differ from the stated enrollment is not reported in the registry record. The approach to accounting for church-level assignment, repeated measurements, or the intervention sequence in the analysis is also not reported in the registry record. These design details matter when interpreting group estimates because the primary result is not accompanied by a direct model-based comparison.

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: A total of 93 participants were assessed for eligibility, and 33 were excluded. 60 participants were consented and randomized to treatment. Participants were randomly assigned to the intervention or delayed intervention (control) group. At the end of a 6-month follow-up period, the control participants will receive the intervention (delayed intervention group).

DPP Intervention (6 Months)

Delayed Intervention (6 Months)

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.

6. Primary Endpoint

The registry lists the primary outcome as Change in Diastolic Blood Pressure (mm/Hg) Over a 6-month Period, measured over Baseline, 6 months.

The primary endpoint is mean change in diastolic blood pressure, measured in mmHg, from baseline to 6 months. The registry defines change as the 6-month measurement minus the baseline measurement. This direction means that a positive change represents a higher measured value at 6 months than at baseline; the posted means for both groups are positive.

Diastolic blood pressure is the lower of the two blood pressure readings commonly recorded together. In general, repeated measurement of a continuous outcome can describe how a group’s average value changes over time. A mean is useful for conveying the central change across participants, while the confidence interval conveys uncertainty around that estimate. Neither the mean nor its interval describes every participant’s experience, and the group average may not capture variation in individual changes.

The registry reports baseline-to-6-month change separately for the immediate and delayed groups. It does not post a treatment-effect estimate comparing those changes, such as a difference between group means, nor a p-value for that comparison. As a result, the endpoint summaries describe the observed arm-level changes but do not establish the size or precision of a relative intervention effect. Other cardiometabolic measures are part of the study’s rationale and monitoring, but the primary result is specifically diastolic blood pressure.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry reports continuous-outcome summaries as means with 95% confidence intervals. The primary measure is the mean change in diastolic blood pressure between baseline and 6 months. Change is defined as the later measurement minus baseline. This makes the sign interpretable: a positive mean indicates that the average measured value was higher at follow-up than at baseline. The group estimates are 6.1 mmHg for immediate intervention and 10.3 mmHg for delayed intervention.

What does a confidence interval describe?

In general, a confidence interval expresses uncertainty around an estimated quantity under a specified statistical method. A narrower interval indicates greater precision for that estimate, while a wider interval indicates less precision. The intervals reported for the two groups are 2.1 to 10.0 and 5.4 to 15.2. Each interval pertains to its group’s mean change. It is not an interval for individual participant values, and it is not an interval for the difference between the groups.

For a comparative question, the quantity of interest would ordinarily be a between-group contrast in change, accompanied by an uncertainty interval and possibly a test result. The registry record does not report such a contrast, a p-value, or a statistical analysis for the primary outcome. The group summaries therefore do not support a formal conclusion about the precision or statistical significance of a relative effect.

Why does the design affect analysis?

Randomized assignment can support comparisons by making groups comparable on average, but the description says that two churches were assigned to the intervention sequences. When assignment occurs at a group or cluster level, participant outcomes within a church may be related. In general, an analysis that treats every participant as fully independent may not reflect that dependence. The registry record does not report whether or how church-level clustering was addressed.

The registry metadata labels the model crossover. The narrative describes immediate and delayed sequences, with the delayed group receiving the program after the first 6 months and the immediate group moving to observation. In general, crossover designs require clear definition of periods, sequences, and the comparisons being made; outcomes may also depend on when participants receive an intervention. The registry record does not report the statistical model, period effects, carryover assessment, or a comparison using data from both periods. The posted primary endpoint is specifically baseline to 6 months.

What can planning calculations tell readers?

In general, sample-size planning uses assumptions about the effect to be detected, variability, significance level, allocation, and analysis method. Planning illustrations are hypothetical requirements under those assumptions; they are not observed trial power and do not describe what the completed study achieved. The stated planning assumptions use a two-sided significance level of 0.05, equal allocation, a normal approximation, and effects expressed as fractions of the observed effect. The record specifies that non-time-to-event planning values are participants per arm. The registry record does not report the trial’s own sample-size justification, so these planning assumptions should not be mistaken for its original design rationale.

Observed power is not a useful substitute for reading the estimated effect and its uncertainty. In general, the precision of the posted estimates is conveyed more directly by their confidence intervals and by the number of participants contributing to each summary. Here, the endpoint summaries list 20 and 23 participants. The record does not state why those counts differ from the enrollment of 60, and no analysis population definition is reported.

What is absent from the inferential record?

No primary statistical analysis is posted, and the registry record lists zero analyses. No adjustment strategy, covariate set, model specification, handling of repeated measures, or missing-data method is reported in the registry record. Without these details and a comparative estimate, the posted means and confidence intervals should be interpreted as arm-level descriptive results. They do not supply a complete test of whether the intervention sequences produced different changes.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists five outcome measures, but no secondary results are posted. It lists zero analyses, and the primary outcome is presented as separate group summaries without a between-group test. A multiplicity strategy—how inference would be controlled when several outcomes or comparisons are considered—is not reported in the registry record. Consequently, there is no reported hierarchy of outcomes or adjustment procedure to use when interpreting multiple statistical tests.

The primary endpoint summaries include 20 participants in the immediate group and 23 in the delayed group, while the listed enrollment is 60. The record does not report why the endpoint counts differ from enrollment. It does not specify how missing measurements were handled, whether participants with incomplete follow-up were excluded, or whether any imputation or sensitivity analysis was used. The analysis population, including whether the summaries use all randomized participants or another set, is not reported in the registry record.

These omissions limit assessment of potential bias from missing outcome data and make it difficult to understand how the posted endpoint sample was formed. They also prevent verification of whether the analysis followed an intention-to-treat approach or another prespecified population. The registry record does not report a protocol-level statistical plan, and no reason for the absence of those details should be inferred from the results alone.

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 registry safety figures report zero serious adverse events and zero deaths in both intervention groups. They also report zero other adverse events in both groups. The record lists 60 participants at risk for serious events and 60 at risk for other events in each group.

The number reported at risk in each group does not match the group counts shown for the primary endpoint, and the record does not explain that difference. The figures should therefore be read as the safety counts as recorded, rather than reconciled with the primary endpoint population. The record does not provide event descriptions because no serious-event terms are listed.

Zero recorded events means that none were entered for the reported categories in this registry record. It does not establish that no events occurred outside the recorded reporting scope, and it does not explain how safety events were collected or adjudicated. The duration and completeness of safety ascertainment are not reported in the registry record. These safety entries are counts, not a comparative statistical analysis of risk between the intervention sequences.

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

The posted primary results describe the average change in diastolic blood pressure from baseline to 6 months within each intervention sequence. The immediate group’s mean change was 6.1 mmHg, with a 95% confidence interval from 2.1 to 10.0; the delayed group’s was 10.3 mmHg, with a 95% confidence interval from 5.4 to 15.2. Under the stated direction of calculation, each mean is positive and represents a higher average follow-up measurement than baseline.

These summaries do not show whether the intervention caused a change. They also do not quantify how much the two sequences differed, because a comparative effect estimate and its uncertainty are not reported. A treatment effect cannot be established by treating the arm means as if they were a direct comparison. The registry record does not provide a p-value or a formal test for the primary comparison.

The estimates concern diastolic blood pressure, not every risk factor named in the study description. Although the program includes remote monitoring of blood pressure and body composition, results for other measures are not posted as secondary outcomes. The record also does not report participant-level distributions, so the group means cannot show the range or pattern of individual responses.

The study is described as a pilot and has an enrollment of 60. The primary endpoint summaries include 20 participants in one group and 23 in the other, with no explanation of the difference from enrollment. The record does not report a sample-size justification or analysis population. These features, together with the absence of a direct comparison analysis and details about the church-level design, mean that the results are most appropriately read as descriptive estimates, not as a definitive test of efficacy.

13. Why This Trial Matters Statistically

This trial is statistically notable because its intervention is delivered in a community setting where churches are described as the units assigned to immediate or delayed intervention. When assignment is organized by groups rather than independently for each participant, the design and analysis need to account for the possibility that participants in the same setting have related outcomes. The registry record does not report how this issue was addressed, so the design structure is important context for interpreting the posted participant-level summaries.

The record also identifies a crossover model while describing an initial immediate-versus-delayed sequence and a later intervention period. That combination raises questions about which periods and comparisons are represented in the primary result. The reported endpoint covers baseline to 6 months; analysis of later follow-up or of both sequences is not reported in the registry record.

The primary result demonstrates why arm-level estimates are not interchangeable with a comparative effect. Each group has a mean change and confidence interval, but no direct contrast is posted. A reader can describe the observed group changes and their uncertainty, but cannot recover a formal intervention comparison from those summaries alone without making additional assumptions or calculations.

Finally, enrollment and endpoint counts differ, while the reason is not reported. Missing-data methods, analysis populations, and the statistical plan are also not reported. These details matter for a pilot study because they determine what the estimates represent and how much confidence to place in them. The record’s main statistical contribution is therefore a set of descriptive six-month blood pressure estimates and a clear set of unanswered design and analysis questions.

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 leaves several trial-specific limitations unresolved. It describes random assignment of two churches, but does not explain how the small number of church-level units was incorporated into the statistical analysis. The record also labels the design crossover, while its narrative describes immediate and delayed intervention sequences. How those descriptions fit together, and what analysis accounts for sequence or period, are not reported in the registry record.

The primary endpoint summaries are available for 20 participants in the immediate group and 23 in the delayed group, compared with enrollment of 60. The reason for the difference is not reported. The record does not identify the analysis population, explain missing measurements, or describe exclusions. These gaps prevent a clear assessment of how representative the endpoint summaries are of enrolled participants.

No between-group effect estimate, confidence interval for a contrast, or primary-outcome test is posted. No model specification or adjustment for baseline values is reported in the registry record. The primary summaries therefore do not provide the comparative inference needed to distinguish changes over time in each group from a relative intervention effect.

The record identifies five outcome measures but posts no secondary results. It does not report a multiplicity plan, protocol-based sample-size justification, or details of safety-event ascertainment. The safety entries list 60 at risk in each group, without explaining how that count relates to endpoint counts. These limitations concern what can be learned from the registry record and do not establish that the underlying study lacked procedures not described there.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: A Virtual Cardiometabolic Health Program for African Immigrants: The Afro-DPP Program — NCT05144737.
• Registry record last updated 2026-04-23; status last verified 2026-04.
• Results first posted 2026-04-22.
• 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

NCT05144737 is a completed pilot study sponsored by Johns Hopkins University. It evaluates a virtual adapted Diabetes Prevention Program for African immigrants, with immediate and delayed intervention sequences and remote blood pressure and body-composition monitoring. The registry describes random assignment at two churches, labels the model crossover, and identifies an unmasked design.

The primary outcome is mean change in diastolic blood pressure from baseline to 6 months. The immediate group’s estimate is 6.1 mmHg, with a 95% confidence interval from 2.1 to 10.0, among 20 participants. The delayed group’s estimate is 10.3 mmHg, with a 95% confidence interval from 5.4 to 15.2, among 23 participants. No direct comparative estimate or inferential test is posted.

The registry reports enrollment of 60 and lists five outcome measures, with no secondary results posted. It does not report the reason for the endpoint counts, the analysis population, missing-data methods, or the statistical approach to the design. Safety counts list zero serious adverse events, zero other adverse events, and zero deaths in both groups.