Biobehavioral Pathways Underlying Alcohol Use and Health: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Biobehavioral Pathways Underlying Alcohol Use and Health (NCT05135767), a non-randomized na study. The primary outcome is Percentage of Screen Eligible Who Enroll.

2. Clinical Question

The clinical context is the overlap between alcohol use disorder and alcohol-associated liver disease. The registry describes alcohol-associated liver disease as a spectrum of liver tissue injury caused by chronic and excessive alcohol use, and notes that alcohol use disorder can involve craving and continued drinking despite harms. It also states that reducing drinking is a treatment goal, while acknowledging that this can be difficult for some people with alcohol-associated liver disease.

This study is framed as a feasibility project, not as a randomized test of whether the intervention is better than another treatment or no intervention. Its stated primary endpoint focuses on whether eligible people enroll. The registry record does not report an observed enrollment percentage, the number screened eligible, or a comparison of enrollment rates between the groups. It therefore does not answer whether enrollment met the stated target, nor does it establish a treatment effect on drinking or health outcomes.

3. Trial Design

This completed study, titled “Biobehavioral Pathways Underlying Alcohol Use and Health,” is registered as a non-randomized, parallel study. The registry lists Brown University as the sponsor and identifies alcohol use disorder and liver diseases as its conditions. The listed enrollment is 37. The start date is 2022-02-28, the primary completion date is 2023-10-27, and the status is completed.

Participants are categorized into an alcohol use disorder-only group or an alcohol-associated liver disease plus alcohol use disorder group. The registry describes the former as meeting criteria for alcohol use disorder without evidence of advanced alcohol-associated liver disease. The latter meets criteria for alcohol use disorder and has evidence of advanced alcohol-associated liver disease. Both groups receive brief motivational interviewing with personalized feedback. Allocation is non-randomized, and masking is listed as none.

Because group membership reflects disease status rather than random assignment, the groups are not like-for-like treatment arms. Any difference between them could reflect differences associated with the groups’ clinical characteristics, as well as other factors; the registry record does not describe an adjusted analysis that could address such differences. The registry’s stated primary endpoint is the percentage of screen-eligible people who enroll, rather than a between-group treatment effect.

The study description places the project in the context of future collaboration between addiction scientists and hepatologists. The brief summary says the project establishes a partnership to support future collaboration. That context is relevant to the feasibility focus: the listed primary measure concerns recruitment from among eligible people. Details such as the recruitment procedures, intervention duration, eligibility criteria beyond the group descriptions, and any planned follow-up assessments are not reported in the registry record. The phase is listed as not applicable.

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.

Baseline

Reasons for not completing this period:

Active Study Phase

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Overall Number of Participants Analyzed in each Arm/Group is the number of participants who screened eligible for the 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: The "Overall Number of Baseline Participants" is the count of participants who were included in analyses addressing primary aims. Since Aim 1 evaluates the feasibility of retention between "Screening" and "Baseline" visits, this overall number is the count of participants who were eligible at the "Screening" visit. For ease of interpretation, the participant flow may be viewed as a multiple baseline design, with the "Screening" visit interpreted as "Baseline 1" and "Baseline" as "Baseline 2."

6. Primary Endpoint

The registry lists the primary outcome as Percentage of Screen Eligible Who Enroll, measured over 3 months.

The primary endpoint is “Percentage of Screen Eligible Who Enroll.” It measures the proportion of people screened as eligible for the study who go on to enroll as participants. The registry describes the target enrollment rate as greater than or equal to 60% of those screened eligible and gives a timeframe of 3 months.

This endpoint is used to assess recruitment feasibility. A recruitment measure can help indicate whether a study can enroll people from the population it seeks to study. It addresses whether eligible people enter the study, not whether the intervention changes drinking, liver health, or another clinical outcome. It also does not by itself describe whether participants remain in the study or complete assessments.

The registry record does not report the number of people screened eligible or the observed percentage who enrolled. The listed enrollment is 37, but that number alone is not enough to determine the primary endpoint: the denominator must be the number screened eligible, and the record does not state it. No enrollment-rate estimate or uncertainty interval is reported. Consequently, the posted results do not establish whether the target was reached.

The population description says that the number analyzed in each group for this endpoint is the number of participants who screened eligible. This explains how the endpoint population is characterized in the registry, but the record does not give group-specific screen-eligible counts or a completed analysis. The endpoint should therefore be read as a planned feasibility measure rather than as a reported result.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Statistical interpretation begins with identifying what was measured and how participants entered the groups. In this study, the primary endpoint is an enrollment proportion: the number of eligible people who enroll relative to the number screened eligible. The registry record states the target but does not report the observed numerator or denominator. Without both, there is no reported proportion to interpret, and no direct way to assess the target.

What does the non-randomized design imply?

In a randomized study, assignment to groups is made by a random process. Random assignment can help balance measured and unmeasured characteristics on average, although it does not guarantee identical groups. Here, allocation is listed as non-randomized. The groups are defined by alcohol use disorder alone versus alcohol use disorder with advanced alcohol-associated liver disease, and both receive the same intervention. They therefore represent clinical categories, not alternative treatment assignments. A difference between them would be an association between group membership and an outcome, not a randomized estimate of intervention benefit.

General statistical principle: when groups differ in clinical status, other characteristics may also differ. Such differences can complicate interpretation because a group contrast may reflect more than the characteristic used to define the groups. The registry record does not report a statistical adjustment plan or adjusted results, so no adjustment should be assumed.

What would an enrollment estimate tell a reader?

General statistical principle: a proportion is interpreted together with its denominator. The same number of enrollments can correspond to different recruitment rates depending on how many eligible people were screened. A confidence interval, when reported, describes the statistical uncertainty around an estimated quantity under the assumptions of the analysis. It does not correct a missing denominator, make a non-randomized comparison causal, or account automatically for biases in recruitment.

The registry identifies a target of greater than or equal to 60% of screen-eligible people enrolling. Because no observed rate or interval is reported, the target cannot be compared with an estimate. The listed enrollment of 37 is a study-level enrollment figure; the registry does not report the screen-eligible count needed to calculate the primary endpoint. No recalculated enrollment estimate is reported, and none can be recovered from the registry entries.

How should the group counts be read?

The adverse-event record lists the alcohol use disorder-only group with 29 participants at risk and the alcohol-associated liver disease plus alcohol use disorder group with 8 participants at risk. For each group, the serious-event affected count is 0, the other-event affected count is 0, and deaths are 0. These group-specific entries describe the safety data as recorded. They do not replace a primary-endpoint analysis, and they should not be treated as evidence of a treatment contrast because the groups were not randomized to different interventions.

General statistical principle: event counts can be sparse, and a zero count does not prove that the underlying risk is zero. The precision of an estimate depends on the amount and structure of the data, and an uncertainty interval would help convey that precision when an appropriate estimate is reported. The registry does not report such intervals for these safety figures. It also does not provide further detail about how events were collected or adjudicated.

Why are no treatment-effect calculations appropriate?

The record does not report clinical outcome results or analyses, and both groups receive the same brief motivational intervention with personalized feedback. There is no randomized untreated or alternative-treatment group in the described design. A calculation comparing the groups as though one were a control would not represent a like-for-like treatment contrast. No recalculated treatment effect is reported. The registry’s own analysis would take precedence if a recalculated result conflicted with it, but no sponsor analysis for the primary endpoint is reported in the registry record.

The record lists 0 analyses. That does not establish why analyses are absent, whether analyses were conducted outside the registry, or what statistical methods may have been used. The planned statistical model, confidence-interval method, missing-data method, and adjustment strategy are not reported in the registry record. None should be inferred from the study title, endpoint, or completion status.

What is the role of sample-size illustrations?

General statistical principle: a prospective sample-size calculation describes the amount of information a study might need to detect a prespecified effect under stated assumptions. A calculation based on an observed effect is instead an illustrative planning exercise; it does not show that the completed study had a particular probability of detecting an effect. Such illustrations are not observed power. The registry record does not report the study’s own sample-size justification, and the described primary result is not available to support an enrollment-based planning comparison. Any planning illustration should therefore be read as a hypothetical design aid, not as evidence about this study’s findings.

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("Alcohol Use Disorder Only", "Alcohol Associated Liver Disease + Alcohol Use Dis")
n      <- c(29, 8)
events <- c(28, 5)
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  Alcohol Use Disorder Only  29  28  96.6  82.2  99.9  82.8  99.4  82.8  99.2
ARM  Alcohol Associated Liver Disease + Alcohol Use Dis  8  5  62.5  24.5  91.5  30.6  86.3  29.9  86.3

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 3 outcome measures and 0 analyses. It does not report a multiplicity adjustment, a prespecified hierarchy for outcomes, or an explanation of how multiple outcomes would be interpreted together. Without an analysis plan and reported results, it is not possible to assess whether the study controlled the chance of false-positive findings across multiple statistical tests. No such testing results are reported for the primary endpoint.

The primary endpoint description identifies the screen-eligible population, but the number screened eligible and the observed enrollment rate are not reported in the registry record. The record also does not explain whether any eligible people lacked enrollment information or how such cases would be handled. The missing-data approach, reasons for missing data, and extent of missingness are not reported in the registry record.

The record does not report a statistical analysis population for the clinical outcomes, or whether any analysis was conducted according to a prespecified population. It describes the primary endpoint population in terms of people screened eligible, but gives no completed endpoint analysis. Details of exclusions, deviations, or participant flow are not reported in the registry record. The listed enrollment of 37 does not supply the missing screening denominator or establish how many people contributed to a particular analysis.

These omissions limit interpretation rather than proving that a particular method was or was not used. The registry record does not report the analysis plan, so no assumptions about multiplicity control, imputation, or handling of incomplete records should be made.

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.

The registry reports safety counts separately for the alcohol use disorder-only group and the alcohol-associated liver disease plus alcohol use disorder group. The former has 29 participants listed at risk and the latter has 8. In each group, the number affected by serious adverse events is 0, the number affected by other adverse events is 0, and deaths are reported as 0. No serious adverse-event terms are listed.

These are descriptive counts in the registry record. They indicate that the posted results contain no affected participants in the listed serious-event or other-event categories, and no deaths, for these groups. They do not show how events were defined, collected, or assessed, and the record does not provide event timing, duration, severity details, or participant-level descriptions. The record also does not state whether every participant had complete safety follow-up.

General statistical principle: zero observed events should not be interpreted as proof that an event cannot occur or that risk is absent. Counts are most informative when accompanied by clear definitions, follow-up information, and estimates of uncertainty. Those details are not reported in the registry record. These safety figures should not be interpreted as a randomized comparison, because the groups were not assigned to different interventions.

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

The registry record establishes that this was a completed, non-randomized study of people with alcohol use disorder, grouped according to whether they also had evidence of advanced alcohol-associated liver disease. Both groups received brief motivational interviewing with personalized feedback. The listed enrollment is 37, and the primary endpoint concerns the share of screen-eligible people who enrolled, with a stated target of greater than or equal to 60%.

The posted results do not report the number screened eligible or the observed enrollment percentage. They therefore do not show whether the recruitment target was achieved. The listed enrollment count alone cannot answer that question, because the rate depends on the number screened eligible. No uncertainty estimate for the primary endpoint is reported.

The study also does not provide a randomized comparison between the intervention and a control condition. Both groups received the same intervention, and their membership reflects clinical status. The record contains no reported analysis of intervention effects on drinking or health outcomes. It cannot establish that the intervention caused a change, nor can it establish that the intervention had no effect.

The safety record reports zero participants affected by serious adverse events and zero affected by other adverse events in each group, with deaths reported as 0. These counts describe what the registry reports; they do not demonstrate absence of risk or supply a complete account of safety monitoring.

The project’s stated role is to build a partnership supporting future collaboration between addiction scientists and hepatologists. Its feasibility focus is relevant to that aim, but the missing recruitment result prevents an assessment of the primary endpoint from the registry record. Overall, the record supports describing the study design and reported counts, while leaving the recruitment outcome and clinical effects unresolved.

14. Why This Trial Matters Statistically

Recruitment feasibility is an important statistical concern when research targets people with overlapping clinical conditions. A study’s ability to enroll eligible participants affects whether its planned questions can be studied and whether future research can be organized around a similar population. This registry identifies an enrollment target and a screen-eligible population, making recruitment the central reported question.

The study also brings attention to a design distinction that matters for interpretation. Participants are grouped by disease status rather than randomly assigned, and both groups receive the same intervention. This structure can describe feasibility and characteristics across clinical groups, but it does not provide a randomized estimate of the intervention’s effect. Keeping that distinction clear helps prevent a group comparison from being read as a treatment comparison.

The project’s stated aim to establish collaboration between addiction scientists and hepatologists gives the feasibility focus a broader research context. The intersection of alcohol use disorder and alcohol-associated liver disease is the clinical setting described in the registry. The posted record, however, does not report an enrollment rate, so it cannot establish whether recruitment met the stated target or quantify the feasibility result.

Statistically, the case also illustrates why a count without its relevant denominator may not answer a rate-based question. Enrollment is listed, but the number screened eligible is not. The distinction is central to the primary endpoint and prevents calculation of the intended proportion. The record is therefore informative about the intended measurement and study structure, while leaving the main feasibility result unreported.

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 registry record does not report the observed primary endpoint, the number screened eligible, or a confidence interval for the enrollment rate. As a result, the stated target cannot be assessed from the posted results. Although the enrollment is listed as 37, this does not supply the denominator required for the rate.

The non-randomized design creates an important limitation for any comparison between the clinical groups. Group membership is defined by whether advanced alcohol-associated liver disease is present, and both groups receive the same intervention. The groups are not a treatment and control pair. The registry record does not report adjustment methods or analyses that would address differences between these groups.

The record lists 3 outcome measures but 0 analyses, and it does not report clinical outcome estimates for drinking or liver health. The statistical plan, sample-size justification, missing-data methods, analysis populations, and multiplicity procedures are not reported in the registry record. The record also does not provide the screen-eligible counts or participant flow needed to understand recruitment in greater detail.

Safety information is limited to group-level counts: zero affected by serious adverse events, zero affected by other adverse events, and deaths reported as 0 in each group. Event definitions, follow-up completeness, timing, severity, and other descriptive details are not reported in the registry record. These limits do not establish that events were absent beyond what was recorded, nor do they establish the completeness of safety reporting.

The project’s partnership-building purpose is described, but the registry record does not report how the partnership was evaluated or what future work resulted. Completion status alone cannot resolve the missing endpoint and analysis information.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Biobehavioral Pathways Underlying Alcohol Use and Health — NCT05135767.
• Registry record last updated 2024-09-19; status last verified 2024-09.
• Results first posted 2024-09-19.
• 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

This completed, non-randomized, parallel study is titled “Biobehavioral Pathways Underlying Alcohol Use and Health” and is sponsored by Brown University. The registry lists enrollment of 37 and identifies alcohol use disorder and liver diseases as conditions. Participants are grouped as alcohol use disorder only or alcohol-associated liver disease plus alcohol use disorder. Both groups receive brief motivational interviewing with personalized feedback; masking is listed as none.

The primary endpoint is the percentage of people screened eligible who enroll, with a target of greater than or equal to 60% and a timeframe of 3 months. The registry record does not report the screen-eligible count or observed enrollment rate, so the target cannot be assessed from the posted results. The record lists 3 outcome measures and 0 analyses.

For both groups, the registry reports zero participants affected by serious adverse events and zero affected by other adverse events, with deaths reported as 0. The non-randomized groups are not a like-for-like control comparison, and no clinical treatment-effect analysis is reported.