Promoting Engagement and COVID-19 Testing for Health: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Promoting Engagement and COVID-19 Testing for Health (NCT06141850), a randomized na study. The primary outcome is Number of Participants With Symptoms Who Use a COVID-19 Test.

2. Clinical Question

Project PEACH2 asks whether a community-based text messaging intervention can encourage COVID-19 testing and preventive behaviors among people affected by diabetes. Its primary question is specifically about participants who report COVID-19 or COVID-like symptoms: how many of them also report taking a COVID-19 test during the relevant period? The study compares an intervention arm with a control arm, with both groups having access to a text-based tool for reporting COVID-19 testing.

This is a behavioral intervention comparison, not a comparison of medication or vaccine regimens. Both groups receive text messages, but their stated message content differs. The intervention is described as lasting 16 weeks, with follow-up lasting 12 months in total. The primary outcome description specifies assessments at baseline and Weeks 4, 8, and 12; it does not describe the primary outcome as a measure collected throughout the full follow-up period.

The registry record does not report the number of symptomatic participants at each assessment, how many used a test, or an estimated difference between arms. It therefore states the question and measurement schedule, but does not provide an answer to the comparative question.

3. Trial Design

The registry record classifies Project PEACH2 as randomized, with a parallel-group model and no masking. It lists Emory University as the sponsor and COVID-19 as the condition. The study is marked completed. Its enrollment is listed as 290. The record gives a start date of 2023-12-06 and a primary completion date of 2025-01-08.

Participants were to be assigned to the Project PEACH2 Intervention or Control Group. In the intervention group, participants received access to a text-based COVID-19 reporting tool and weekly behavioral nudges by mobile phone text message. The stated purpose of the nudges was to encourage COVID-19 testing and preventive behaviors. The control group also received access to the reporting tool, along with weekly texts addressing diabetes prevention, management, or care. Thus, the stated comparison is between different text-message content, with reporting-tool access in both groups.

The intervention period is described as 16 weeks, while total follow-up is described as 12 months. The primary outcome schedule is narrower: baseline and Weeks 4, 8, and 12. Baseline measurement used survey data, while the later measurements used the study’s text-based reporting tool. The registry record does not state how the randomized sequence was generated, whether assignment was concealed, or whether any procedures beyond the listed allocation and masking classifications were used.

The study is listed as phase NA. The record does not report a sample-size justification, target effect used in the original design, or a detailed protocol for the planned statistical analysis. It also does not report participant flow, adherence to assigned message content, or the number completing each assessment. These omissions limit what can be established about implementation and analysis from the registry record alone.

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: The number of participants analyzed at each time point are participants reporting symptoms of COVID-19.

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 Number of Participants With Symptoms Who Use a COVID-19 Test, measured over Baseline, Weeks 4, 8, and 12.

The primary endpoint is the number of participants with symptoms who use a COVID-19 test. The registry description defines this as participants reporting both COVID-19 or COVID-like symptoms and taking a COVID-19 test in the past month. The stated unit is participants, and the outcome is a count rather than a continuous measurement such as a score.

The outcome is assessed at baseline and Weeks 4, 8, and 12. At baseline, the information comes from survey data. At Weeks 4, 8, and 12, it comes from the study’s text-based COVID-19 reporting tool. The registry record says that the number analyzed at each time point consists of participants reporting COVID-19 symptoms. This means that the count is defined within a symptom-reporting population, rather than simply as a count among every person enrolled at every assessment.

As a general statistical rationale, an endpoint focused on testing among symptomatic participants can address a behavior tied to the stated intervention goal: encouraging testing when symptoms occur. The repeated assessment schedule can describe that behavior at several points during the intervention period. These design features do not, by themselves, establish that the intervention changed testing behavior. Interpretation requires the observed counts and a defined comparison between arms at the relevant time points.

The registry record does not report the endpoint values, the numbers of symptomatic participants, or a statistical comparison. It also does not state how missing symptom or testing reports were handled. Accordingly, the endpoint can be described from the measurement definition, but its observed level and comparative result are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Several statistical ideas are relevant to interpreting the stated design, even though the registry record does not report a primary outcome analysis. The explanations below are general; they should not be read as a description of methods confirmed to have been used by Project PEACH2.

What does randomization contribute?

In general, randomization assigns participants to study groups using a chance-based process. When implemented as planned, it helps make the groups comparable on average with respect to both measured and unmeasured characteristics at the time of assignment. It does not guarantee that the groups will be identical, and it does not resolve problems such as missing outcome data, non-adherence, or measurement differences. The registry record identifies the allocation as randomized but does not report the sequence-generation or concealment procedures.

The parallel-group designation means the record describes separate intervention and control arms rather than a crossover in which participants switch conditions. The record also specifies no masking. That classification does not reveal whether outcome collection or analysis had any safeguards against knowledge of assignment; those details are not reported in the registry record.

How should a count outcome be understood?

The primary outcome is a count of participants meeting a combined definition: reporting symptoms and taking a COVID-19 test in the past month. A count can be informative, but its interpretation depends on the population contributing to it. Here, the registry record says that participants analyzed at each time point are those reporting COVID-19 symptoms. If the number reporting symptoms differs across arms or time points, the raw count of test users alone does not express the same testing frequency in every group. A rate or proportion would require a clearly stated denominator, and the registry record does not provide such denominators or say how the primary comparison would be expressed.

Counts collected repeatedly also require careful handling of time. Measurements from the same participant may be related rather than statistically independent. A suitable analysis, when repeated measurements are present, generally needs to account for the outcome definition, dependence between observations, the comparison of interest, and missing measurements. The registry record does not report a model, a time-point contrast, or a method for handling within-participant dependence.

What does a comparison estimate?

As a general concept, an effect estimate describes the contrast between outcomes under the conditions being compared. The form of that estimate depends on the endpoint and analysis plan. For a count-based endpoint, possible summaries could be based on counts, proportions, or another model-based contrast, but no particular form should be attributed to this study without a reported analysis plan. The registry record does not provide an estimate for the primary outcome, so it is not possible to describe its magnitude or direction.

Precision is often conveyed with a confidence interval. In general, an interval gives a range of values compatible with the observed data under the chosen method and assumptions. An interval that spans a wide range conveys less precision than a narrow interval. A confidence interval is not reported for the primary outcome in the registry record. A p-value is also not reported. Neither the existence of randomization nor the completed study status can replace these results.

Why can counts require special modeling?

As a general statistical point, some count outcomes vary more than a simple model assumes. This is called over-dispersion: the observed variation exceeds the variation expected under that model. If over-dispersion is present and not handled appropriately, standard errors and confidence intervals may be inaccurate. Whether over-dispersion is relevant depends on the actual outcome distribution and chosen model. The registry record provides neither the primary outcome data nor a model description, so it is not possible to assess this issue for Project PEACH2 or to claim that any particular count model was used.

The endpoint is described as a number of participants, not as a person-time event rate. No exposure-time denominator or event-rate model is reported. Methods for analyzing recurrent event rates should therefore not be assumed from the count wording alone.

What do the planning assumptions mean?

The registry record describes a planning illustration based on the 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 and that non-time-to-event planning quantities are expressed as participants per arm. These are planning assumptions, not results from the trial and not observed power. No planning values or observed effect estimates are reported in the registry record, and the original trial’s sample-size justification is not reported there. The illustration therefore cannot establish that the trial was adequately powered or explain how its enrollment target was chosen.

More generally, sample-size planning concerns the number of participants needed under assumptions about the outcome, effect, variability, allocation, and statistical procedure. A planning illustration that uses an observed effect is dependent on that effect estimate and is not proof that the same effect is true. It should not be interpreted as a probability that the study’s findings are correct. No such probability is reported for Project PEACH2.

What can be inferred from an absent analysis?

The registry record lists zero registered analyses and does not give an outcome comparison. This is an absence of reported analysis in the record, not evidence that the true intervention effect is zero. It also does not establish that no analysis was performed outside the registry. The appropriate conclusion is limited: the statistical results needed to quantify the primary comparison are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry record lists a primary outcome and two secondary outcomes: the percent of participants receiving COVID-19 vaccination and the number adhering to COVID-19 prevention behaviors. The primary outcome is assessed at baseline and Weeks 4, 8, and 12. Multiple outcomes and assessment times can create more than one opportunity to test a hypothesis. As a general statistical principle, interpreting many comparisons without a plan can increase the chance of findings that appear noteworthy by chance. The registry record does not report a multiplicity adjustment, a hierarchy for testing outcomes, or a detailed plan identifying which time-point contrast would be primary.

The record explicitly notes that the primary outcome has several categories or time points and is not reduced to one comparison. It lists zero registered analyses. No p-values, confidence intervals, or outcome-level comparisons are reported, so there is no multiplicity-adjusted or unadjusted result to interpret.

Missing-data handling is not reported in the registry record. The record does not state how missing symptom reports, missing test reports, missed assessments, or incomplete reporting-tool entries were treated. It also does not give the number of participants with data at each assessment. This matters because the primary outcome population is defined by symptom reporting; missing symptom information could affect who is included in the count.

The analysis population beyond the stated symptom-reporting population is not reported in the registry record. It does not state whether the primary analysis was intended to include all randomized participants, only participants with available outcome data, or another defined population. No approach to non-adherence, withdrawal, or changes in participation is specified. These gaps prevent assessment of how missingness and analysis-population choices might influence any estimated comparison.

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 record lists serious adverse events for the Project PEACH2 Intervention and Control Group. For each group, it records 145 participants at risk and 0 serious events. It also records 145 participants at risk and 0 other adverse events for each group. Deaths are listed as 0 in each group, and no top serious-event terms are listed.

These are the safety figures recorded in the registry. A zero in an adverse-event field means that the record lists no events for that category; it does not establish that every possible symptom or harm was systematically captured, or that no unlisted event occurred. The record does not describe the adverse-event collection procedures, observation windows, event definitions, or completeness of reporting. It also does not provide event-level narratives or additional safety analyses.

The listed at-risk counts are safety-field denominators and should not be treated as evidence about the primary outcome population. The primary outcome is restricted in its description to participants reporting symptoms at each time point, whereas the adverse-event fields concern safety reporting. These safety entries do not indicate whether the intervention changed COVID-19 testing or other behavioral outcomes.

Accordingly, the appropriate reading is that the registry record lists zero serious events, zero other adverse events, and zero deaths in each group within its reported safety fields. The scope and completeness of the underlying safety ascertainment are not reported in the registry record.

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

The record establishes the study’s intended comparison and the way its primary behavioral outcome was defined. Both groups had access to a text-based COVID-19 reporting tool. The intervention group additionally received weekly COVID-19 testing and prevention nudges, while the control group received weekly diabetes-related texts. The study was randomized and parallel-group, with the intervention described as lasting 16 weeks and total follow-up described as 12 months.

It does not establish the effect of that intervention. The registry record does not report how many symptomatic participants used a COVID-19 test, how those counts differed between groups, or how uncertain any difference might be. It gives no primary outcome estimate, confidence interval, or p-value. It also does not report results for vaccination or adherence to COVID-19 prevention behaviors. Consequently, the record cannot show whether the intervention increased, decreased, or left unchanged any of these outcomes.

The primary measure has a specific interpretation: it concerns participants reporting symptoms and testing during the past month. It is not a general measure of all testing, testing among all participants, or testing across the entire 12-month follow-up. The specified measurement times are baseline and Weeks 4, 8, and 12. Later measurements use a reporting tool, whereas baseline uses survey data; the record does not report whether or how differences in measurement source were addressed analytically.

The completed status means the study is marked completed in the registry, but completion alone does not supply outcome evidence. Likewise, the enrollment listing and safety counts cannot be used to reconstruct the primary outcome. The listed zero adverse-event counts are limited to the safety fields and do not answer the behavioral research question.

As a general statistical principle, a study’s design can make a comparison informative, but results still require observed outcome data, an analysis definition, and an account of uncertainty. Those elements are not reported for the primary comparison in the registry record. The result therefore remains unquantified in this record; no conclusion about benefit, lack of effect, or harm should be drawn from the missing efficacy results.

13. Why This Trial Matters Statistically

Project PEACH2 is statistically notable for separating two components of text-based support. Both groups had the COVID-19 reporting tool, while the stated weekly message content differed: COVID-19 testing and prevention nudges in the intervention arm, and diabetes prevention, management, or care messages in the control arm. This design frames the comparison as the added effect of the intervention’s COVID-19-focused messaging relative to the control messaging, rather than as messaging versus no messaging.

The primary outcome also focuses on a defined behavior in a defined subgroup: test use among participants reporting COVID-19 or COVID-like symptoms. That focus makes the denominator and assessment schedule central to interpretation. The record specifies baseline and Weeks 4, 8, and 12, but does not report the number reporting symptoms or the observed testing counts at those times. Without those details, neither the scale of the behavior nor the arm comparison can be evaluated.

The study includes secondary outcomes concerning vaccination and prevention behaviors, which are related but distinct behaviors. Each would need its own clear definition and analysis to support an interpretation. The registry record identifies these outcomes but does not report their results or a plan for handling multiple outcomes and time points.

The most important statistical point is the distinction between a completed randomized study and a reported comparative result. The record documents the study structure, measurement intent, and safety entries, but lists no registered analyses and no primary outcome estimate. This makes clear which information is needed before the central question can be answered: arm-specific outcome data, denominators, a defined comparison, and an account of uncertainty and missing data.

These features make the record useful for understanding the question the trial was designed to address, while also marking the limits of what can be concluded from the registry entry. The design is not itself evidence that the intervention changed behavior.

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 trial-specific limitation in the registry record is the absence of reported outcome results. There are no primary endpoint counts by arm or time point, no effect estimate, and no uncertainty measure. The record lists zero registered analyses and explicitly does not reduce the multi-time-point primary outcome to a single comparison. This prevents a direct statistical assessment of the central question.

The primary outcome depends on symptom reporting, but the record does not give the number of symptomatic participants at each assessment. Without those denominators, the count of test users cannot be interpreted as a frequency among symptomatic participants or compared reliably across assessment times. The record also does not state how missing symptom or testing reports were handled.

Measurement differs by time point: baseline uses survey data and later assessments use the text-based reporting tool. The record does not report the extent of missing reports or whether the change in measurement source was addressed in an analysis. It does not provide details on adherence to the assigned messages, participant flow, or completion of follow-up assessments.

The statistical plan is not reported in sufficient detail to identify the intended estimand, model, handling of repeated observations, or approach to multiplicity. The original sample-size justification is also not reported. A planning illustration based on an observed effect is described, but no illustration values or primary effect estimate are given in the registry record; that description cannot establish the study’s design assumptions or power.

Finally, the adverse-event fields list zero events but do not describe ascertainment procedures or completeness. These limitations concern what can be learned from the registry record and should not be taken as evidence that the study did not collect further information elsewhere.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Promoting Engagement and COVID-19 Testing for Health — NCT06141850.
• Registry record last updated 2026-02-23; status last verified 2026-02.
• Results first posted 2026-02-23.
• 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

Project PEACH2 is a completed randomized, parallel-group study sponsored by Emory University. The registry record lists enrollment as 290 and describes a community-based study targeting people affected by diabetes. The intervention combines a text-based COVID-19 reporting tool with weekly COVID-19 testing and prevention nudges. The control group has access to the same tool and receives weekly diabetes-related texts.

The primary outcome is the number of participants reporting symptoms who used a COVID-19 test in the past month, assessed at baseline and Weeks 4, 8, and 12. The intervention is described as lasting 16 weeks, with total follow-up of 12 months. Two secondary outcomes concern COVID-19 vaccination and prevention behaviors.

The registry record does not report primary or secondary outcome results, comparative estimates, confidence intervals, or p-values, and it lists zero registered analyses. Safety fields list zero serious events, zero other adverse events, and zero deaths in each group. These entries do not answer the primary behavioral question.