Responses to Message Source and Presentation Using Psychophysiology: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Responses to Message Source and Presentation Using Psychophysiology (NCT06269003), a randomized na study. The primary outcome is Visual Attention.

2. Clinical Question

3. Trial Design

The registry describes a randomized factorial study of electronic-cigarette public education messages. It lists four conditions that combine two message sources—expert and peer—with two presentation formats—one-sided and two-sided. Participants in each condition received messages corresponding to that combination. The factorial structure makes it possible to examine source and presentation as distinct factors, although the registry record does not report the planned statistical contrasts or whether an interaction between the factors was assessed.

The enrollment is 112. The study is listed as completed, with a start date of 2024-02-18 and a primary completion date of 2024-06-10. The phase is listed as NA. Allocation is randomized, and masking is listed as none. These registry labels describe the recorded design; further details about sequence generation, allocation concealment, or implementation are not reported in the registry record.

The study includes current vapers and susceptible non-vapers, and the visual-attention outcome description says results were stratified by vaping status. The number analyzed for each outcome row was intended to reflect participants in that status group included in the analysis. The actual analyzed counts for the visual-attention outcome are not reported in the registry record.

Attitudes and behavioral intentions are listed as secondary outcomes. The record identifies five outcome measures overall, but does not provide numerical outcome summaries or analysis records. It also does not report a protocol-level sample-size justification, details of recruitment, or the criteria used to define susceptibility among non-vapers.

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 data were stratified based on participants' vaping status ("Current vapers" and "Susceptible non-vapers"). The Number of Participants Analyzed for each row reflects the actual number of participants within that vaping status group who were included in the analysis. The Overall Number of Participants Analyzed represents the total number of both subgroups. Any differences have been clarified to specify participant numbers at the row level.

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 Visual Attention, measured over The entire duration of message from beginning of its delivery to the completion of viewing, up to 45 minutes..

The listed primary endpoint is visual attention, measured as dwell time in milliseconds. Dwell time is the length of time a participant looked at specified areas of interest while viewing a message. The record states that dwell times were collected for 18 messages and aggregated to an average dwell-time score for each arm, separately for current vapers and susceptible non-vapers. The viewing period covered the message from the beginning of delivery through completion of viewing, up to 45 minutes.

Dwell time is an attention measure: it describes how long participants looked at selected parts of the messages. The registry interprets higher dwell-time scores as greater visual attention and describes higher attention as indicating better message outcomes. This is an operational definition for the study, not evidence that a message changed attitudes or behavior. Attitudes and behavioral intentions are separately listed as secondary outcomes.

For a continuous measure such as dwell time, a mean describes the average recorded value, while a standard deviation describes the spread of participant values around that mean. Those are the summary-statistic types specified in the registry. Numerical means, standard deviations, and participant counts for the endpoint are not reported in the registry record, so the size and precision of any differences among conditions cannot be assessed from the recorded information.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The outcome is described as a continuous measure summarized by a mean and standard deviation. General explanation: a mean represents the average observed dwell time, while a standard deviation indicates how dispersed individual dwell-time values are around that average. These summaries describe the data; by themselves they do not test whether conditions differ. The registry record does not report the endpoint means or standard deviations.

What does the factorial design distinguish?

The four message conditions cross source (expert or peer) with presentation (one-sided or two-sided). General explanation: a factorial analysis can estimate the contribution of each factor while also evaluating whether the association with one factor depends on the level of the other. That dependence is commonly called an interaction. The registry identifies the design as factorial but does not report the statistical model, the contrasts, or whether an interaction was included in the analysis.

Comparisons could be framed in different ways, such as comparing sources while accounting for presentation, comparing presentation formats while accounting for source, or comparing individual combinations. Those are general examples of possible questions, not claims about the study’s analysis plan. The precise comparisons planned or performed are not reported in the registry record.

How should precision be assessed?

General explanation: an estimate is more informative when its uncertainty is described alongside its size. A confidence interval is one way to express that uncertainty; a narrower interval generally indicates greater precision under the stated method and assumptions. The registry record does not report confidence intervals, standard errors, or test results for visual attention. Therefore, neither the precision of the estimated differences nor their compatibility with a range of plausible values can be assessed from the record.

The registry describes a sample-size planning illustration based on a fraction of an observed effect. Its stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The illustration is not the trial’s own design justification. Numerical planning results and the effect fractions used are not reported in the registry record. Such sample-size calculations are planning illustrations, not observed power and not evidence that a study did or did not detect an effect.

Why can over-dispersion matter?

General explanation: over-dispersion occurs when observed variability is greater than a statistical model expects. If a model assumes less variability than the data contain, uncertainty estimates can be too small and tests can appear more conclusive than warranted. The listed dwell-time summary uses a standard deviation, but the record does not report a model or diagnostics that would establish whether over-dispersion was relevant or how variability was handled. No model-specific inference can be reconstructed from the registry information.

What can be learned from the analysis records?

The registry lists zero analysis records. It also gives no numerical primary-outcome summaries. As a result, there is no posted estimate to interpret and no reported statistical method to audit. The description of the outcome and design should not be mistaken for evidence of a particular treatment or message effect. Any further account of model adjustment, covariates, handling of repeated message observations, or decision thresholds would go beyond what is reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures overall, including visual attention as the primary outcome and attitudes and behavioral intentions as secondary outcomes. It does not report numerical results for these outcomes. The record also indicates that the primary outcome has several categories or time points and was not reduced to one comparison. The specific categories or time points are not detailed in the available registry information.

Multiplicity arises when several outcomes, contrasts, subgroups, or time points are examined. General explanation: the more statistical questions considered, the greater the chance that at least one result may appear unusual by chance if each is assessed separately. Methods such as a prespecified hierarchy or adjustment can address particular multiplicity concerns, but the registry record does not report whether any such approach was planned or used. It also does not identify which comparisons were treated as primary within the factorial design.

Missing-data procedures and the amount of missing outcome information are not reported in the registry record. The endpoint description says the analyzed participant number would be stated for each vaping-status row, but actual analyzed counts are not reported. Reasons for exclusion, missing observations, or any imputation approach are also not reported in the registry record.

The description distinguishes current vapers and susceptible non-vapers, but detailed analysis-population definitions and participant flow are not reported. The enrollment count should therefore not be treated as the endpoint analysis count. With zero analysis records and no posted outcome estimates, it is not possible to determine how multiplicity or missingness affected the reported results.

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 adverse-event record lists four groups: Expert 1-sided, Expert 2-sided, Peer 1-sided, and Peer 2-sided. For each group, the counts recorded for serious adverse events, other adverse events, and deaths are 0. The corresponding numbers at risk are 28, 28, 27, and 28 for the four groups in that order.

These figures describe what the registry record reports, not a complete characterization of safety. A recorded count of 0 means no event in that category was entered for the listed group in this record. It does not establish that no event occurred outside the recorded reporting process, nor does it provide information about event definitions, surveillance, duration of follow-up, or completeness of reporting. Those details are not reported in the registry record.

The groups correspond to message-source and presentation assignments. The figures should be read as event counts with the listed numbers at risk, not as estimates of comparative risk. No statistical comparison of adverse events is reported. The record also does not report serious adverse-event terms, consistent with the absence of listed serious events.

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

The record describes a randomized factorial study asking whether expert versus peer message sources and one-sided versus two-sided presentation relate to young adults’ responses to electronic-cigarette public education messages. Its primary outcome is visual attention measured by dwell time, with vaping status used to stratify the outcome population. Attitudes and behavioral intentions are listed as secondary outcomes.

What the registry record does not provide is the numerical result needed to answer whether the message conditions differed. There are no reported endpoint means, standard deviations, confidence intervals, p-values, or analysis records. The direction, size, and precision of any differences are therefore not reported in the registry record. It is not possible to identify a message source or presentation format as having produced more visual attention based on these details.

Even if a difference in dwell time were reported, general interpretation would remain bounded by what the measure represents: time spent looking at selected message areas. Attention is not itself a direct measure of a change in attitudes, intentions, or behavior. The record lists those as separate secondary outcomes, but their numerical results are not reported in the registry record.

The recorded completion status and enrollment establish that the study is listed as completed and enrolled 112 participants. They do not supply missing results or clarify how many participants contributed to each endpoint analysis. Likewise, a planning illustration based on an observed effect would not constitute observed power or a substitute for the trial’s outcome estimates. Numerical planning results are not reported in the registry record.

Accordingly, the defensible interpretation is about the study’s question and design, not the comparative performance of its message conditions. The posted information does not support a conclusion about which condition was preferable or whether any observed difference was precise, statistically distinguishable, or meaningful beyond the measured attention outcome.

13. Why This Trial Matters Statistically

This study is statistically interesting because it uses a factorial design to examine two message features: source and presentation. Separating those features can help distinguish whether responses are associated with who delivers a message, how the message presents its argument, or a combination of both. Whether the analysis actually estimated those effects and their interaction is not reported in the registry record.

The outcome also illustrates the importance of matching a measure to the question. Dwell time captures visual attention to defined message areas, while attitudes and behavioral intentions are separately named outcomes. These measures address different aspects of response. In general, evidence about attention should not be treated as interchangeable with evidence about attitudes or intentions.

Stratification by vaping status is another relevant design feature. A combined estimate could obscure different response patterns between current vapers and susceptible non-vapers, while subgroup estimates may be less precise. General explanation: subgroup interpretation depends on the numbers analyzed and the uncertainty around each estimate. The registry record does not report those endpoint counts or estimates.

The study also highlights a distinction between a completed trial record and an interpretable results record. The registry identifies the design, enrollment, outcome definition, and adverse-event counts, but lists zero analysis records and does not report numerical primary-outcome results. Without estimates and uncertainty measures, readers can identify the intended statistical question but cannot assess its answer.

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 limitation for statistical interpretation is the absence of numerical results for the primary endpoint. Means, standard deviations, analyzed counts, and inferential estimates are not reported in the registry record. The record lists zero analysis records, so there is no reported model or comparison to evaluate.

The factorial design is described, but the exact statistical contrasts and treatment of a possible source-by-presentation interaction are not reported in the registry record. The primary outcome description refers to multiple categories or time points that were not reduced to one comparison; the specific categories or time points are not stated. This leaves the intended inferential structure unclear.

Although the endpoint is stratified by current vaping status and susceptible non-vaping status, the actual analyzed participant counts within those groups are not reported. Missing-data handling, exclusions, participant flow, and outcome completeness are also not reported in the registry record. The enrollment count alone does not show how many observations contributed to each analysis.

The record does not report details about how randomization was implemented, the definition of susceptibility, or the statistical model used for dwell-time observations. The sample-size description concerns a planning illustration rather than a reported design justification, and its numerical results are not available. Finally, adverse-event counts are recorded as zero, but the registry does not describe surveillance or reporting procedures. These limitations constrain interpretation of the record; they do not establish what the unreported analyses or procedures found.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Responses to Message Source and Presentation Using Psychophysiology — NCT06269003.
• Registry record last updated 2025-08-01; status last verified 2025-07.
• Results first posted 2025-08-01.
• 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

NCT06269003 is listed as a completed, randomized factorial study with enrollment of 112. Its registered title concerns responses to message source and presentation using psychophysiology. Four electronic-cigarette message conditions combine expert or peer sources with one-sided or two-sided presentation. Masking is listed as none, and phase as NA.

The primary outcome is visual attention measured by dwell time in milliseconds, summarized as a mean and standard deviation and stratified by current vapers and susceptible non-vapers. Attitudes and behavioral intentions are listed as secondary outcomes. The adverse-event record lists zero serious adverse events, other adverse events, and deaths in each group.

Numerical primary-outcome results, analyzed counts, and inferential analyses are not reported in the registry record. The record lists zero analysis records, so the comparative effects of the four message conditions cannot be assessed from the recorded results.