Genetic and Neural Factors in Alcohol-Related Cognition: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Genetic and Neural Factors in Alcohol-Related Cognition (NCT03725345), a randomized na study. The primary outcome is Changes in Alcohol-influenced Behavior.

2. Clinical Question

The study title refers to genetic and neural factors in alcohol-related cognition, while the posted primary outcome concerns task-based aggressive behavior. The record states that Aims 1–3 were covered by another protocol, and that the results apply only to Aim 4. It does not report a genetic or neural outcome analysis for this record. The primary outcome compares group-level averages on a scale from 1 to 4, where a higher score represents selection of louder noise blasts. The available group summaries describe the observed scores, but the record does not report an estimable statistical comparison between groups. Accordingly, the posted information does not establish whether the observed group means differ beyond what could arise from sampling variability.

3. Trial Design

The registry record describes a completed, randomized, single-masked, parallel study with an enrollment of 9. The study began on 2023-07-11, and primary completion was recorded as 2024-11-01. The listed condition is Alcohol Abuse, and the sponsor is Virginia Commonwealth University. The record lists the phase as NA.

The two result groups are called Alcohol Group and No Alcohol Group. Their descriptions distinguish participants by whether they had recently consumed alcohol, but the record does not explain the timing or method used to determine recent consumption. Although allocation is listed as randomized, the record does not explain what was randomized, how randomization was implemented, or whether alcohol exposure itself was assigned. The listed intervention is an MRI Scanner, categorized as behavioral. Further intervention details are not reported in the registry record.

The trial model is parallel. The outcome description says that participants completed a single session and performed the loud-noises task twice consecutively within that session. The description ends mid-sentence, so additional details about the session or task sequence are not reported in the registry record. The identity of the party masked under the single-masked designation is also not reported.

Results are reported for 5.0 participants in the Alcohol Group and 4.0 in the No Alcohol Group. Their primary-outcome means are 1.56 and 1.49 units on a scale, respectively; the corresponding standard deviations are 0.72 and 0.56. No confidence interval, hypothesis test, or estimable two-group comparison is reported. These design and reporting details are important context: the group summaries are descriptive, and the registry entry does not state enough to assess the randomization process, masking, or the analysis plan in detail.

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

Analysis population for the primary outcome, as defined in the registry: The results apply only to Aim 4. Aims 1-3 were covered by another protocol that did not meet the definition of a ct and were approved under a different IRB protocol #. All participants completed only one session, but within that session, they performed the loud noises task twice consecutively on the same MRI scan.It was done twice to get a more reliable answer when the two measures were combined.

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 Changes in Alcohol-influenced Behavior, measured over During the course of the MRI session.

The primary endpoint is titled “Changes in Alcohol-influenced Behavior.” It measures aggressive behavior during the MRI session using the Taylor Competitive Reaction-Time Task. Participants select noise-blast settings for an opponent across multiple trials. Each setting uses a four-point scale ranging from 1, low noise-blast volume and low aggression, to 4, high noise-blast volume and high aggression. The settings are averaged into a total score from 1 to 4; higher values indicate greater aggression on this task.

The endpoint is reported as a mean with a standard deviation, which is appropriate to describe the location and spread of a continuous score. The registry record specifies the timeframe as during the MRI session and describes comparing scores after recent alcohol consumption with scores without recent consumption. The reported group means are 1.56 for the Alcohol Group and 1.49 for the No Alcohol Group. Their standard deviations are 0.72 and 0.56, respectively.

The task offers a standardized way to quantify one specific behavior under the study conditions. It does not directly measure every aspect of aggression, cognition, alcohol-related behavior, or neural activity. The registry does not report additional validation details beyond describing the task as validated and computerized. Nor does it report an estimable statistical comparison for the two group summaries. The endpoint therefore supports description of the recorded task scores, but the posted results do not establish the precision or statistical evidence for a between-group difference.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

General statistical context: the primary endpoint is continuous because it is a numerical score on a scale. A mean summarizes the central location of observed scores, while a standard deviation describes how dispersed those scores are around their mean. The record reports the endpoint as a mean with standard deviation. In the Alcohol Group the mean is 1.56 and the standard deviation is 0.72; in the No Alcohol Group the mean is 1.49 and the standard deviation is 0.56. These descriptive statistics are not, by themselves, a test of whether the groups differ.

What does a group mean describe?

A sample mean is the arithmetic average of the recorded scores in that group. Its value depends on the participants observed and their scores. A standard deviation describes variation among individual scores in the same group, rather than uncertainty about the mean or the difference between groups. General statistical context: when a sample is small, each observation can have a noticeable effect on the mean and standard deviation. The reported group sizes are 5.0 and 4.0, so the summaries represent a small number of participants.

The scale is bounded from 1 to 4, with higher scores indicating selection of louder noise blasts and greater aggression according to the task definition. A mean can be useful for a continuous score, but it does not show the complete distribution of individual observations. The registry does not report individual scores or other distributional summaries. Therefore, features such as skewness, clustering, or the presence of an unusual observation cannot be assessed from the reported means and standard deviations.

Why is a comparison estimate useful?

A formal comparison would quantify the contrast between the two groups and describe uncertainty around that estimate. General statistical context: a confidence interval gives a range of values that are compatible with the data under a stated model and method. A hypothesis test evaluates data against a specified null hypothesis and produces a test result, often including a p-value. These tools answer related but distinct questions; neither replaces scrutiny of the design, measurement, and assumptions.

The registry record does not report an estimable two-group comparison for this continuous outcome. It does not report a confidence interval, test statistic, or p-value. Consequently, no inferential conclusion about the size or precision of the group contrast can be drawn from the posted result. The absence of an estimate does not mean the group means are identical; it means the record does not present an inferential comparison.

What assumptions might matter for continuous data?

General statistical context: common methods for comparing means rely on assumptions about how observations were generated. Depending on the method, relevant considerations can include independent observations, the shape of the outcome distribution, and whether the groups have similar variances. With very small samples, it is difficult to diagnose these features from summaries alone. The registry does not report which comparison method was planned or used, diagnostics of assumptions, or any adjustment for unequal variance. It would therefore be inappropriate to attribute a particular method or assumption check to this analysis.

General statistical context: over-dispersion means that observed variability is greater than a model expects. It can make standard errors and tests from an inadequately specified model unreliable. The registry does not report a model-based analysis or an over-dispersion assessment, and the primary outcome is described as a bounded score summarized by a mean and standard deviation. There is no basis in the record to say that over-dispersion occurred or that a particular model was needed. This concept is relevant only as a general reminder that an analysis should match the outcome and its observed variation.

What do the planning illustrations mean?

The registry describes planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation, and a normal approximation. Such calculations ask how many participants per arm might be needed to detect a specified fraction of an observed effect under stated assumptions. They are planning illustrations, not observed power and not a substitute for the study’s original sample-size justification. The numerical outputs of those illustrations are not reported in the registry record, and the record does not report the trial’s own sample-size justification.

General statistical context: a planning calculation depends on the assumed effect, variability, significance level, desired power, allocation, and analysis method. When an effect estimate comes from a small study, it may be imprecise, so calculations based on that estimate can also be unstable. A planning illustration cannot establish that a completed study had a particular probability of detecting an effect after the data have been observed. The study’s enrollment of 9 is the reported enrollment, not a measure of power.

What can be assessed from the posted analysis record?

The record lists one outcome measure and zero posted analyses. It does not report the analysis method, a prespecified primary contrast, covariate adjustment, handling of repeated task trials, or any inferential result. The task description says multiple trials are averaged to provide a total score, and the population text says the task was performed twice consecutively within one session. How trial-level or repeated-task information contributed to the reported participant scores is not fully described. These details matter for understanding the unit of analysis and the uncertainty calculation, but no further procedure should be inferred.

The stated random allocation and the consumption-based group descriptions also leave design questions unanswered. The record does not explain what was allocated, how the groups were formed, or whether the exposure was assigned. These omissions limit interpretation of any causal contrast. The reported means remain useful descriptive summaries, but the methods necessary to evaluate an inferential comparison are not reported in the registry record.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Alcohol Group", "No Alcohol Group")
n   <- c(5, 4)
m   <- c(1.56, 1.49)
sp  <- c(0.72, 0.56)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Alcohol Group  5  1.560  0.720  0.666  2.454
CARM  No Alcohol Group  4  1.490  0.560  0.599  2.381

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists one outcome measure and zero posted analyses. It lists no secondary outcome results. This means there is no set of reported outcome tests in the record from which to evaluate whether multiple-comparison adjustments were used. A multiplicity plan, including any hierarchy of outcomes or adjustment procedure, is not reported in the registry record. It would be inappropriate to assume that no other analyses were conducted simply because no analyses are posted.

Missing-data handling is not reported in the registry record. The reported group sizes are 5.0 and 4.0, but the entry does not say whether all enrolled participants contributed a valid primary score, whether any scores were incomplete, or how missing or unusable measurements would have been handled. It also does not report an imputation method or a sensitivity analysis. The listed enrollment of 9 and the result group counts do not, on their own, establish the completeness of the outcome data or the analysis population.

The analysis population is not fully defined. The population description says the results apply only to Aim 4 and notes that Aims 1–3 were covered by another protocol. It does not report inclusion and exclusion criteria for the analysis, whether participants were analyzed according to an assigned group, or how any deviations from the intended procedures were treated. The record says each participant completed one session, but it does not give a full account of the relationship between the task being performed twice and the final participant-level score.

These reporting gaps do not demonstrate that multiplicity or missing-data problems occurred. They mean that the registry record does not provide enough information to assess how those issues were addressed. With no inferential comparison posted, the effects of analysis choices on uncertainty and statistical evidence cannot be evaluated.

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 serious adverse events for 0 of 5 participants at risk in the Alcohol Group and 0 of 4 participants at risk in the No Alcohol Group. It also reports other adverse events for 0 of 5 and 0 of 4 participants at risk, respectively. Deaths are reported as 0 in both groups. No serious adverse event terms are listed.

These figures describe the adverse-event entries in the registry for the stated groups and risk counts. They should not be interpreted as proof that no adverse events could occur, or as a precise estimate of safety. The number of participants is small, and the record does not provide further detail about adverse-event collection, definitions, observation duration, or how events were attributed. Those details are not reported in the registry record.

Zero reported events in a small group leaves substantial uncertainty about event frequencies that might occur in a larger population or over a different observation period. The primary endpoint concerns a task score and is not a safety outcome. The adverse-event counts are therefore separate descriptive information, not evidence about the effectiveness of any intervention.

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

The result establishes that the registry reports mean task scores of 1.56 in the Alcohol Group and 1.49 in the No Alcohol Group, with standard deviations of 0.72 and 0.56, respectively. The endpoint is the average noise-blast setting selected during a computerized task, scored on a scale from 1 to 4. The task description interprets higher values as greater aggression within that task. These are group summaries for the participants represented in the posted results.

The result does not establish whether the groups differ statistically or how precisely a group contrast is estimated. No confidence interval or hypothesis-test result is reported, and an estimable two-group comparison is not available in the registry record. The descriptive means alone cannot determine whether an underlying difference exists. They also cannot show that no difference exists.

The result does not establish that alcohol consumption caused a change in behavior. Although allocation is listed as randomized, the record does not clarify what was randomized or how randomization relates to the descriptions of recent alcohol consumption. That distinction is important when interpreting a comparison as causal. The posted information also does not establish an effect on behavior outside the task, on alcohol misuse, on cognition more broadly, or on genetic and neural factors.

The group sizes are small, with 5.0 and 4.0 participants reported. General statistical context: estimates from small samples are often imprecise, and the group summaries can be sensitive to individual observations. Because no inferential estimate is posted, the size of that uncertainty cannot be quantified from this record.

The registry reports zero serious adverse events, zero other adverse events, and zero deaths in the listed groups. Those counts apply to the reported participants and do not establish an absence of risk in other settings or populations. Overall, the posted result is descriptive and specific to a task conducted during an MRI session. It does not support a broader clinical conclusion.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of the difference between reporting descriptive summaries and reporting an inferential comparison. Group means and standard deviations help readers understand the observed scores, but they do not show the estimated contrast’s precision. The record reports the descriptive values for both groups while not reporting an estimable two-group comparison, confidence interval, or hypothesis test. That distinction is central when interpreting clinical and behavioral research.

The small reported group sizes also make transparent uncertainty especially important. General statistical context: with few observations, a mean and standard deviation may be strongly influenced by individual scores, and estimates of variability can themselves be unstable. A confidence interval and a clearly described analysis could help readers assess the extent of uncertainty, but neither is available in the registry record.

The design description highlights why the relationship between allocation and exposure matters. Randomized allocation is listed, while the groups are described according to recent alcohol consumption. The record does not explain how those statements fit together. Clear reporting of the assigned condition, exposure measurement, and analysis population would help readers determine what comparison the study was designed to make and what conclusions the design can support.

The endpoint is a defined behavioral task score rather than a broad measure of cognition or a direct assessment of genetic or neural factors. Keeping interpretation aligned with the measured outcome prevents a narrow task result from being generalized to a wider construct. The registry’s note that these results apply only to Aim 4 further sets a boundary around what this record addresses.

Finally, the record lists one outcome measure but no posted analyses, and it does not describe missing-data handling or the analysis plan. These omissions illustrate why reporting the method, population, uncertainty, and limitations alongside summary statistics is essential for evaluating evidence. The posted data remain useful as a description of the observed scores, but the inferential and design context needed for a fuller assessment is not reported.

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 primary limitation is that the registry record does not report an estimable comparison between the two groups. It gives means and standard deviations but no confidence interval, test result, or method for quantifying uncertainty in a group contrast. Consequently, the magnitude and precision of any difference cannot be assessed from the posted results.

The reported groups are small: 5.0 participants in the Alcohol Group and 4.0 in the No Alcohol Group. Descriptive estimates from small groups may be sensitive to individual scores, and the record does not include individual-level results or distributional information. The scale is bounded from 1 to 4, but the record does not describe whether the statistical approach accounted for that bounded measurement.

The design description leaves important questions open. Randomized allocation is listed, but the relationship between allocation and the groups defined by recent alcohol consumption is not explained. The process for determining recent consumption, the masking procedure, and the identity of the masked party are not reported in the registry record. The listed MRI Scanner intervention does not clarify those points.

Details of the task and analysis are incomplete. The outcome description states that the task was performed twice consecutively within one session, but the population description ends mid-sentence. The record does not fully describe how repeated task performance contributed to each reported score, or how the observations were analyzed. Analysis-population definitions, missing-data handling, the statistical plan, and any sample-size justification are not reported.

Finally, the reported endpoint is one task-based measure of noise-blast selection. It does not capture every dimension of aggression, cognition, or alcohol-related behavior. The record does not report genetic or neural outcome analyses for this Aim 4 result. These limitations restrict interpretation to the posted descriptive summaries and the specific task context.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Genetic and Neural Factors in Alcohol-Related Cognition — NCT03725345.
• Registry record last updated 2026-01-05; status last verified 2025-12.
• Results first posted 2026-01-05.
• 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

The registry record describes NCT03725345, “Genetic and Neural Factors in Alcohol-Related Cognition,” as a completed, randomized, single-masked, parallel study sponsored by Virginia Commonwealth University. Enrollment was 9. The listed intervention is an MRI Scanner. The outcome reported for Aim 4 is a task-based aggression score during the MRI session, measured using the Taylor Competitive Reaction-Time Task on a scale from 1 to 4.

The Alcohol Group includes 5.0 reported participants and has a mean of 1.56 with a standard deviation of 0.72. The No Alcohol Group includes 4.0 reported participants and has a mean of 1.49 with a standard deviation of 0.56. The registry does not report an estimable two-group comparison, confidence interval, or hypothesis-test result. It lists zero serious adverse events, zero other adverse events, and zero deaths in both groups. The record does not report the analysis plan, missing-data approach, or sample-size justification.