Mobile Evidence-Based Smoking Cessation for Veterans Living With HIV (MESH): Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Mobile Evidence-Based Smoking Cessation for Veterans Living With HIV (MESH) (NCT04135937), a na phase 4 study. The primary outcome is Number of Participants Who Participate in the Post-treatment Interview.

2. Clinical Question

The central research question is exploratory: how do Veteran smokers living with HIV describe their preferences and suggestions for a personalized smoking-cessation treatment? The project aimed to explore treatment preferences and refine the intervention’s design and content. Its stated purpose was not to establish a comparative treatment effect against usual care or another assigned intervention.

The background in the registry record describes smoking as a significant cause of damage to health and quality of life for Veterans living with HIV, and notes that smoking-cessation interventions for this population are lacking. MESH combines mobile health and telehealth technology to personalize counseling and medication options, with text messaging intended for relapse prevention. Those elements describe the proposed approach; the record does not establish that every participant received every component.

The post-treatment interview is therefore important as a development outcome: it can elicit feedback on the proposed intervention. It is not itself a measure of smoking cessation. The registry record does not report the interview findings or a numerical count of participants who completed the interview, so it cannot answer how participants evaluated the intervention or how many contributed feedback.

3. Trial Design

MESH (Mobile Evidence-Based Smoking Cessation for Veterans Living With HIV) is recorded as a completed, Phase 4, single-group study. The registry lists an enrollment of 12 and identifies the VA Office of Research and Development as sponsor. The study started on 2019-11-18 and reached primary completion on 2021-07-15. The registry record does not report a comparison arm; allocation is marked not applicable, and masking is listed as none.

The intervention was tailored for participants. Its possible components were cognitive behavioral therapy, relapse-prevention text messaging, and pharmacotherapy with nicotine replacement therapy, bupropion, or varenicline. The description says the approach uses mobile health and telehealth to personalize smoking-cessation counseling and medications and to provide relapse-prevention messages. The record does not report which components each participant received, how treatment choices were made, or how much intervention exposure participants had.

The primary outcome is the number of participants who participate in a post-treatment interview at week 5. The registry explains that the qualitative interview would ask participants what they would change about the proposed treatment. Interview findings were intended to inform treatment development for a randomized controlled trial. This design is consistent with an intervention-development and preference-exploration aim, rather than a controlled test of comparative efficacy.

The registry record does not report the protocol’s sample-size justification, a detailed analysis plan, interim analyses, or a randomized comparison. Although the record identifies the study as completed, a numerical primary-outcome result and qualitative interview findings are not reported in the registry record. Completion status alone does not indicate how many participants completed the interview or what they said.

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:

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 Who Participate in the Post-treatment Interview, measured over Post-treatment follow-up visit (week 5).

The primary endpoint is a count: the number of participants who take part in the post-treatment interview at the week 5 follow-up visit. The interview is described as qualitative and intended to collect participants’ views about changes they would make to the proposed treatment. Those views were meant to inform development of a randomized controlled trial.

A participation count can describe whether the planned feedback activity occurred among enrolled participants. It does not summarize the content, range, or importance of interview comments. Nor does it measure smoking cessation, changes in smoking behavior, or a treatment effect. Those are different outcomes and are not identified as the primary endpoint in this registry record.

For an intervention-development project, participant feedback can help identify preferences and aspects of a proposed approach that merit further refinement. The count alone, however, cannot show what preferences were expressed. Interpretation would ordinarily benefit from the qualitative findings and a clear account of how interviews were conducted and analyzed. Those details and the numerical result for interview participation are not reported in the registry record. Thus, the stated purpose of the endpoint is clear, but its observed value and the substance of the feedback cannot be assessed from the registry information.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes MESH as a single-group study with no masking and no randomized comparator. These design features determine what kinds of statistical conclusions the record could support. A single-group study can describe outcomes among people enrolled in the intervention, but it lacks a concurrent control group for estimating how outcomes would have differed under another assigned treatment. Randomization, in general, helps make comparison groups similar in expectation; it is not listed for this study.

What does a single-group design allow?

Descriptive analysis can report counts or other summaries observed among participants. A causal comparison requires more: a clearly defined alternative condition and a design and analysis that support comparison between the intervention and that alternative. MESH has no control arm listed, and the registry explicitly flags that it is not a randomized comparison. The primary endpoint is interview participation, so the stated aim is to gather feedback for intervention development rather than estimate a treatment contrast.

Because the record does not report a primary-outcome count, even a descriptive summary of interview participation cannot be reconstructed from the registry entry. The enrollment value is not a substitute for the number who took part in the interview. Enrollment describes entry into the study; the endpoint specifically concerns post-treatment interview participation. Treating those as the same measure would conflate different stages of study participation.

What does a count endpoint mean?

A count records the number of participants meeting a stated condition. Here, the condition is participating in the post-treatment interview at week 5. The count does not describe the interview’s content. A count can be useful for documenting whether feedback was obtained, while qualitative analysis is needed to characterize the suggestions and experiences expressed. Neither kind of information is reported as a numerical primary result in the registry record.

For a binary outcome, an analysis might distinguish participants who do and do not meet a defined criterion. General statistical methods can then summarize the observed frequency and, where appropriate, its uncertainty. The registry identifies the endpoint as a participant count, but provides no reported primary analysis, estimate, or uncertainty interval. No inferential conclusion about interview participation can therefore be drawn from the recorded endpoint definition alone.

How should confidence intervals and tests be understood?

In general, a confidence interval describes the range of values compatible with the data and an analysis model at a stated confidence level. Its width conveys precision: wider intervals indicate more uncertainty about the estimate, while narrower intervals indicate greater precision under the model’s assumptions. A hypothesis test addresses a specified null hypothesis and produces a measure of how compatible the data are with that hypothesis. Neither a test nor an interval can replace the effect estimate, and neither establishes clinical importance by itself.

No confidence interval, p-value, or primary-outcome estimate is reported in the registry record. The absence of those statistics means precision and statistical evidence for the primary endpoint cannot be evaluated. It does not imply a null result. Likewise, a lack of reported analyses is not a result showing that the intervention had no effect.

What do the planning assumptions describe?

General planning illustrations are not observed results and are not automatically the design used by the study. The stated illustration assumptions use a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; they describe planning around a stated fraction of an observed effect. The accompanying note distinguishes participants per arm from total events for time-to-event outcomes. These assumptions describe a hypothetical planning exercise, not MESH’s single-group design. Sample-size illustrations are planning quantities, not observed power and not evidence that a study detected an effect.

In general, a sample-size calculation depends on the outcome, target effect, variability or event frequency, allocation, significance level, and desired power. A calculation based on an observed effect can be especially difficult to interpret as a design justification: an observed estimate may be uncertain, and a planning illustration does not establish that the original study was designed around it. The protocol’s own sample-size justification is not reported in the registry record. The registry also does not report a primary-endpoint estimate that would allow an outcome-specific planning interpretation for interview participation.

Why does over-dispersion matter in general?

For count outcomes, some statistical models assume a particular relationship between the average count and its variability. Over-dispersion means the observed counts vary more than the model assumes. If ignored, uncertainty may be understated and tests may be too optimistic. This is a general issue for count-data analysis; the registry does not report a count model, dispersion estimate, or analysis of the interview endpoint. The outcome’s label as a count does not establish that a particular model was used.

For this record, the most defensible statistical reading is descriptive and limited. The design and endpoint can be explained, but the primary outcome’s observed value, uncertainty, and qualitative content are not reported. No model, test, or comparison should be attributed to the study beyond what the registry record states.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("MESH")
n      <- c(12)
events <- c(9)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  MESH  12  9  75.0  42.8  94.5  46.8  91.1  46.2  90.9

11. Multiplicity, Missing Data and Analysis Populations

Multiplicity arises when an analysis evaluates multiple outcomes, treatment contrasts, time points, or hypotheses. In general, conducting many tests can increase the chance of finding at least one apparently unusual result even when there is no true effect. Researchers may address this through a prespecified testing hierarchy, adjustment procedures, or by treating analyses as exploratory. The registry record does not report a multiplicity plan, a hierarchy of outcomes, or an adjustment method. It is therefore not possible to assess how multiple statistical questions, if any, were handled.

The record identifies one primary outcome measure: the number of participants who participate in the post-treatment interview at week 5. It also describes the qualitative purpose of those interviews. No numerical result or analysis is reported for that endpoint. The number of analyses recorded is zero. This does not establish whether analyses were never conducted; it means analyses are not reported in the registry record.

Missing-data methods are also not reported in the registry record. The endpoint depends on participation in a follow-up interview, so an account of interview completion and non-completion would be relevant for interpreting the count. The enrollment figure alone cannot indicate follow-up completion. The record does not describe how unavailable interviews, withdrawals, or other missing information were handled, and it does not provide an analysis population definition.

In general, missing outcomes can affect interpretation when the likelihood of missingness is related to participants’ experiences or outcomes. Different assumptions about missing data can lead to different conclusions. Without reported missingness details and methods, it is not possible to determine whether missing information could have influenced the study’s findings. No imputation, sensitivity analysis, or other missing-data approach is reported in the registry record.

These reporting gaps matter for a preference-focused study as well as for a comparative trial. Knowing who participated in interviews and how the qualitative material was analyzed would help readers judge the scope and transferability of the feedback. Those details are not reported in the registry record.

12. 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 non-serious adverse event terms

The registry lists the MESH group with 12 at risk for serious adverse events and zero affected, and 12 at risk for other adverse events and one affected. No serious adverse-event terms are listed. These are descriptive counts recorded for the study group, not a comparison between assigned treatments.

The serious-event count of zero means no serious adverse event is recorded in this entry for the listed group. It does not show that risk is absent, nor does it establish that the intervention is safer than another option. The other-event count records one affected participant in the group. The registry does not provide further detail about the event’s nature, timing, relationship to the intervention, severity beyond its category, or outcome. Serious adverse-event terms are not reported in the registry record.

Safety counts require context. In general, interpretation depends on how events were defined and collected, the period of observation, and how many participants were followed for safety. The registry lists the group’s at-risk counts but does not report those additional details. With no control group listed, the event figures cannot establish whether event frequency differed from what would have occurred under another treatment or without the intervention.

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

MESH addresses an intervention-development question for Veteran smokers living with HIV. The intervention is described as personalized and may combine counseling, medication options, and relapse-prevention text messaging. The planned post-treatment interview was intended to gather participant suggestions to inform development of a future randomized controlled trial. These aims are distinct from demonstrating that the intervention changes smoking behavior.

The registry record does not report the numerical result for the primary endpoint, which is participation in the week 5 interview. It also does not report the qualitative findings. As a result, readers cannot determine from the registry entry how many participants contributed interview feedback or what changes participants recommended. The study’s completed status does not answer those questions.

The record also does not report a randomized control group, a comparative treatment estimate, or a primary smoking-cessation result. It therefore cannot establish whether MESH improved smoking cessation relative to another approach. It cannot identify which intervention components were received or assess their separate effects. These limits reflect the stated single-group design and the outcomes reported in the registry, not proof that the intervention is ineffective.

The adverse-event entry provides limited descriptive information: zero serious events and one other event are listed for the group. Without further event detail or a comparator, those counts do not establish relative safety. A fuller assessment would need details that are not reported in the registry record.

The most appropriate conclusion is narrow. The registry documents a completed, single-group project focused on exploring preferences and refining a tailored intervention for future research. The primary outcome definition fits that developmental purpose, but the primary result and interview findings are not reported. No conclusion about efficacy, participant acceptance, or comparative safety follows from the information recorded.

14. Why This Trial Matters Statistically

This study is statistically notable because its primary question is developmental and qualitative rather than a conventional comparison of treatment effects. The endpoint is a count of participants taking part in a post-treatment interview. That distinction matters: an interview count can indicate whether feedback was collected, while the interview content is needed to understand preferences and proposed changes. Neither the count nor the qualitative findings are reported as results in the registry record.

The single-group design also sets a clear boundary on inference. Without a listed control group or randomized allocation, the study is not structured as a like-for-like comparison of treatment strategies. Its stated aim—to explore preferences and refine MESH for a future randomized controlled trial—should not be recast as a comparative efficacy claim. The record’s design and its primary outcome are aligned with early intervention development, but they cannot answer a different question about comparative treatment effects.

The tailored nature of MESH makes reporting of intervention exposure especially relevant. The intervention could include several behavioral and medication components, but the record does not report which components participants received. That limits interpretation of any aggregate result and would prevent attribution to a particular component even if a result were available.

Finally, the registry entry illustrates the difference between a completed study record and a reported outcome. Study status, enrollment, and endpoint definitions describe important parts of a trial, but do not substitute for outcome estimates, uncertainty, analysis methods, and qualitative findings. Their absence limits both statistical interpretation and the usefulness of the project as a basis for designing later research.

15. 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 principal limitation for interpreting this trial is that the registry record does not report the primary endpoint result. The endpoint is defined as participation in a week 5 post-treatment interview, but the number who participated is not stated. The registry also does not report interview findings, leaving the central preference-exploration objective unanswerable from this record.

The study is single-group, with no randomized comparator listed. The design therefore does not support a like-for-like estimate of treatment effect against a control condition. The primary endpoint is an interview-participation count rather than a smoking-cessation outcome, and no numerical smoking outcome is reported. Conclusions about cessation or comparative effectiveness would exceed the information recorded.

The intervention is tailored and may include multiple components, but participant-level component exposure is not reported. The record does not describe intervention adherence, treatment choices, or the amount of counseling or messaging received. It also does not provide details about interview conduct, qualitative coding, or how themes were derived. These omissions limit assessment of both intervention delivery and the credibility or transferability of any feedback.

Analysis and missing-data details are not reported in the registry record. There is no reported analysis plan, analysis population, approach to incomplete interviews, or sensitivity analysis. The protocol’s sample-size justification and interim analyses are also not reported. The record lists zero analyses, so no primary estimate, precision measure, or inferential result is available for assessment.

The safety information is limited to event counts. The registry does not supply event descriptions or comparative safety information, and no control group is listed. The record’s completed status and enrollment figure do not resolve these outcome and reporting gaps.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Mobile Evidence-Based Smoking Cessation for Veterans Living With HIV (MESH) — NCT04135937.
• Registry record last updated 2023-07-27; status last verified 2023-07.
• Results first posted 2022-02-16.
• 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.

19. Record Summary

NCT04135937, titled Mobile Evidence-Based Smoking Cessation for Veterans Living With HIV (MESH), is listed as a completed Phase 4, single-group study sponsored by the VA Office of Research and Development. The registry records enrollment of 12, a start date of 2019-11-18, and primary completion on 2021-07-15.

The tailored intervention could include cognitive behavioral therapy, relapse-prevention text messaging, nicotine replacement therapy, bupropion, or varenicline. The primary outcome is the count of participants who participate in a post-treatment interview at week 5. The qualitative interviews were intended to inform treatment development for a future randomized controlled trial.

A numerical result for the primary outcome and the interview findings are not reported in the registry record. No randomized comparator or primary analysis is listed. The adverse-event record lists zero serious adverse events and one other adverse event for the MESH group.