Sign Here: How to Conduct Informed Consent With Deaf Individuals: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Sign Here: How to Conduct Informed Consent With Deaf Individuals (NCT05268055), a randomized na study. The primary outcome is Healthcare Provider Cultural Competency.

2. Clinical Question

This trial addresses whether a training film can be evaluated in a randomized study and whether the study can assess cultural competency after participants engage with training and complete a simulation. The registry describes the research as examining feasibility and preliminary efficacy, but the posted record does not report findings on feasibility or efficacy. It also does not report the results of the secondary outcomes, which concern understanding and retention of the intervention and self-rating of the simulation.

The clinical question is therefore clear at the level of intervention and intended measurement, but its answer cannot be inferred from the registry entries available. Without reported group results and an analysis, the record does not establish whether scores differed, how large any difference was, or how precisely that difference was estimated.

3. Trial Design

The registry describes a randomized, double-masked, parallel trial with an enrollment of 208. The listed phase is NA, and the status is completed. The sponsor is the University of Massachusetts, Worcester. The listed condition is cultural competency.

The experimental intervention was the “Sign Here” training intervention. Participants assigned to it viewed a new training film for healthcare providers. The comparator was intervention as usual: participants reviewed “Communicating with People Who Are Deaf or Hard of Hearing in Hospital Settings.” The record identifies the study as randomized but does not report the method used to generate the allocation sequence or whether allocation was concealed.

Double masking is recorded, but the registry does not report which people involved in the trial were masked or how masking was maintained. The parallel model indicates that randomized groups followed their assigned intervention rather than a crossover arrangement. Further details on intervention delivery, adherence, and the timing of the simulation are not reported in the registry record.

The study start date is 2023-05-03, and the primary completion date is 2023-10-01. The registry summary describes a broader project with focus groups in Year 1 to inform production of the training film, followed by film production and a randomized trial in Year 2. The summary states that the trial was intended to assess feasibility and preliminary efficacy. These aims provide context, but do not substitute for reported trial results.

The registry lists five outcome measures and 15 analyses. It does not describe how those analyses correspond to the outcomes, what statistical models were used, or which analyses were designated as primary beyond identifying healthcare provider cultural competency as the primary outcome. The enrollment figure is not an outcome analysis population: the primary outcome population is specifically described as enrolled participants who reviewed their assigned intervention and completed the study simulation session.

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.

Before assignment: Of the 325 healthcare providers, medical students, and nursing students who were screened, 208 met inclusion criteria, consented to participate in the study, and were subsequently randomized to condition. Study participants were either healthcare professionals or students in healthcare professions. The Deaf standardized patient who participated in outcome simulations was a trained member of our research team, not a study participant.

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Enrolled participants who reviewed their assigned training intervention and completed the study simulation session.

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 Healthcare Provider Cultural Competency, measured over post-intervention, up to one month.

The primary endpoint is healthcare provider cultural competency, measured as a score on a scale. The registry describes the scale as validated and reports that total scores range from 9 to 63. Higher scores indicate higher cultural competency. The planned summary measure is the mean, with standard deviation as the measure of dispersion. The assessment timeframe is post-intervention, up to one month.

A scale score is used to represent the construct of cultural competency in a form that can be summarized and compared across participants. The mean describes the average score in a group, while the standard deviation describes how spread out individual scores are around that average. These are complementary: the mean conveys the group’s central score, and the standard deviation conveys variation among participants. This is a general explanation of these statistics, not a description of observed results.

The registry identifies the primary outcome population as participants who reviewed their assigned training intervention and completed the study simulation session. That definition matters when interpreting any eventual estimate: it describes the participants eligible for the primary outcome assessment, and is narrower than simply referring to everyone enrolled. The number of participants with endpoint data and the handling of participants without endpoint data are not reported in the registry record.

No group means, standard deviations, estimated difference, confidence interval, or test result for this endpoint are reported in the registry record. Accordingly, the scale description explains what the endpoint is intended to measure, but does not show the level of cultural competency observed or whether the randomized groups differed.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Interpreting a randomized trial requires separating the design, the outcome definition, the analysis population, and the numerical results. The registry identifies random allocation, a parallel model, and double masking. Randomization is intended, in general, to make the assigned groups comparable on average, including for factors that may not have been measured. It does not guarantee identical group composition, and it does not by itself resolve problems caused by missing outcome data or incomplete reporting. The registry does not report the sequence-generation or allocation-concealment methods, so those implementation details cannot be assessed.

What does the mean measure?

The primary outcome is a continuous scale score summarized by its mean and standard deviation. In general, a mean is a measure of the group’s central score. A standard deviation describes the variability of scores around that mean. A comparison of means can be expressed as a difference between group averages, but such an estimate needs an uncertainty measure, commonly a confidence interval, to show the range of values reasonably compatible with the data under the analysis assumptions. A confidence interval is not a guarantee that the true value lies within its limits; it communicates statistical uncertainty in the estimate.

The registry does not report either group’s mean or standard deviation, nor an estimated difference or confidence interval. It is therefore not possible to evaluate the magnitude or precision of the primary outcome contrast. A scale’s range and direction aid interpretation of a reported score, but they do not reveal the scores observed in the trial.

What does randomization contribute?

Random assignment creates a basis for comparing outcomes by assigned group, provided that the analysis and follow-up preserve that comparison appropriately. In general, the effect estimate should be interpreted in light of who was analyzed, how participants were handled when they did not complete assessments, and whether the analysis followed the assigned groups. The registry’s primary outcome population requires participants to have reviewed the assigned intervention and completed the simulation. It does not report whether the primary analysis included all randomized participants or used another approach to missing data.

The record states that the allocation was randomized and the model was parallel. It does not provide the statistical model for the endpoint, adjustment variables, or whether the reported analysis, if any, was based on assignment or intervention received. Those omissions prevent a detailed assessment of the analysis method. They should not be filled in by assuming a common approach.

How should statistical significance be read?

In general, a p-value measures how incompatible the observed data are with a specified null model, under the test’s assumptions. It does not measure the probability that the null hypothesis is true, nor does it describe the size or practical importance of an effect. A confidence interval adds information about the estimate’s precision and the range of effect sizes compatible with the data. Neither is reported for the primary outcome in the registry record. No conclusion about statistical significance can be drawn without a reported test result, and no conclusion about the size of a difference can be drawn without an estimate.

The sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation; the intended effect to detect is expressed as a fraction of the observed effect. Such an illustration is a planning calculation, not observed power. It is not evidence that the trial achieved a particular probability of detecting an effect, and it does not replace reporting the outcome estimates. The registry record does not report a sample-size justification for the trial’s original design.

Why can over-dispersion matter?

Over-dispersion is a general issue in statistical models for count outcomes. It occurs when the variation in the observed counts is greater than a model assumes. If a model ignores this extra variation, its standard errors may be too small and its confidence intervals too narrow, making the evidence appear more precise than it is. The primary endpoint in this trial is a continuous scale score, not a count outcome, and the registry does not report the model used for it. This general concept therefore should not be taken as a claim that over-dispersion occurred in this trial.

What does multiplicity change?

Multiplicity arises when several outcomes, comparisons, or analyses are examined. In general, conducting many tests can increase the chance of at least one apparently notable result by chance if no adjustment or prespecified interpretation strategy is used. The registry lists five outcome measures and 15 analyses, but does not report how these analyses were distributed, whether they were prespecified, or whether any multiplicity adjustment was used. It is therefore not possible to determine how multiplicity was handled or how it should affect interpretation of individual results.

These methodological concepts explain what information would be needed to interpret a randomized comparison. They do not supply missing results. For this record, the design and endpoint are described, but the estimates and analysis details required for a numerical assessment are not reported in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures and 15 analyses. It names the primary outcome as healthcare provider cultural competency and identifies assessment of intervention understanding and retention and self-rating of simulation as secondary outcomes. However, it does not map each listed analysis to an outcome, explain which comparisons were planned, or report a strategy for handling multiple analyses.

As a general statistical matter, testing several outcomes or comparisons can increase the chance of obtaining an apparently notable result by chance. Prespecification and appropriate adjustment can help readers interpret a collection of tests, but the registry record does not report whether either was used. No conclusion about the effect of multiplicity on the findings can be made without the analysis plan and results.

The primary outcome population consists of enrolled participants who reviewed their assigned training intervention and completed the study simulation session. The registry does not report the number with primary outcome data, the number missing, reasons for missingness, or methods for handling missing observations. It also does not report whether participants were analyzed according to randomized assignment or under another analysis population definition.

These omissions limit assessment of potential selection from incomplete follow-up and of how representative the primary outcome analysis was of the randomized groups. A completed trial status does not establish that all enrolled participants completed all assessments. The registry record does not report enough information to determine the extent or consequences of missing data.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports zero serious adverse events and zero other adverse events in the “Sign Here” training intervention group, with 103 at risk for each entry. It reports zero serious adverse events among 15 participants at risk in the intervention-as-usual group, and zero other adverse events among 105 participants at risk in that group. Deaths are reported as zero in both groups. These figures are the recorded adverse-event entries, not outcome estimates for cultural competency.

The at-risk counts for intervention as usual differ between serious and other adverse events. The counts should be read separately as recorded, rather than combined or treated as interchangeable denominators. The registry does not explain why they differ, define the event-collection procedures, or report the duration or completeness of safety follow-up.

Zero recorded events means that the registry lists none in these entries; it does not establish that the intervention is free of risk or that every possible event was captured. The record does not provide event descriptions, severity details beyond the serious-versus-other categories, or a statistical comparison of safety outcomes. These figures therefore support only a narrow description of what is recorded, not a broad conclusion about safety.

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

The registry record establishes that a randomized, double-masked, parallel study compared the “Sign Here” training film with intervention as usual, and that healthcare provider cultural competency was designated as the primary outcome. It also describes the scale, its direction, and the population for the primary assessment. This information defines what the trial was intended to evaluate.

The record does not report the primary outcome results. Without group scores, an estimated contrast, and a measure of uncertainty, it is not possible to say whether the groups differed, how large any difference might have been, or how precisely it was estimated. The record’s completed status does not answer those questions. The same limitation applies to the listed secondary outcomes: their results are not reported in the registry record.

The record also does not report enough detail to assess missing data, the full analysis population, or the handling of the 15 listed analyses across five outcome measures. These are important for understanding how closely an analysis reflects the randomized comparison and how to interpret multiple findings. The registry’s description of a feasibility and preliminary efficacy aim should not be mistaken for evidence that feasibility or efficacy was demonstrated.

Accordingly, the posted information supports a description of the trial design and intended measurement, but not a conclusion about the observed effect of the training film. It neither establishes a benefit nor establishes an absence of benefit. The appropriate statistical conclusion is that the outcome evidence needed to answer the comparative question is not reported in the registry record.

13. Why This Trial Matters Statistically

This trial is statistically relevant because it applies a randomized comparison to a training intervention whose intended outcome is a measured construct, cultural competency. Randomization can support a structured comparison between assigned interventions, while the defined scale provides a consistent endpoint for summarizing scores. The registry’s description of the primary outcome population also makes clear that the endpoint is assessed among participants who reviewed their assigned intervention and completed the simulation session.

The study’s stated aims include feasibility and preliminary efficacy, which are distinct questions. Feasibility concerns whether a study and its procedures can be carried out as intended; efficacy concerns outcomes under the trial’s comparison. The registry record does not report feasibility measures or results, and it does not report the primary outcome estimates. Keeping these questions separate prevents an intended study aim from being mistaken for a finding.

The record also illustrates why outcome definitions alone are not enough for statistical interpretation. Means and standard deviations describe a continuous endpoint, but readers also need group results, a contrast estimate, uncertainty, and details about the analysis population and missing data. The listing of five outcome measures and 15 analyses makes clarity about prespecification and multiplicity relevant, yet those methods are not reported.

For this trial, the public record gives a useful account of the randomized design and the intended assessment, while leaving the numerical evidence needed to evaluate the comparison unavailable. Recognizing that boundary is important: a carefully defined question is not the same as a reported answer, and a completed study status is not an effect estimate.

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 interpreting this trial from the registry record is that primary and secondary outcome results are not reported. The record gives the primary endpoint definition but not observed scores, a between-group estimate, or its uncertainty. As a result, the direction, magnitude, and precision of the primary comparison cannot be assessed.

Important analysis details are also not reported. The registry does not describe the statistical model, any adjustment variables, the method used to analyze the primary endpoint, or whether analysis followed randomized assignment. The primary outcome population is defined by intervention review and completion of the simulation, but the record does not report how many participants met that definition or how missing outcome data were handled.

The record lists five outcome measures and 15 analyses, without describing their relationship, prespecification, or any approach to multiplicity. This limits interpretation of the analysis plan and of any individual result that may be available elsewhere. The registry also records double masking without identifying who was masked or how masking was maintained. Sequence generation and allocation concealment are not described.

The safety entries report zero events but include different at-risk counts for serious and other adverse events in the intervention-as-usual group. The record does not explain the difference or detail safety collection and follow-up. These constraints mean that the recorded figures should not be read as a complete assessment of safety.

Finally, the registry describes a feasibility and preliminary efficacy purpose but does not report feasibility findings or the outcome estimates needed to assess preliminary efficacy. These are limitations of what is reported in the registry record; they do not establish that the underlying study lacked those data or analyses.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Sign Here: How to Conduct Informed Consent With Deaf Individuals — NCT05268055.
• Registry record last updated 2024-11-27; status last verified 2024-11.
• Results first posted 2024-11-27.
• 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

The registry describes NCT05268055, “Sign Here: How to Conduct Informed Consent With Deaf Individuals,” as a completed, randomized, double-masked, parallel study with an enrollment of 208. The listed phase is NA. The sponsor is the University of Massachusetts, Worcester, and the condition is cultural competency.

The study compared a training film for healthcare providers with intervention as usual, which involved reviewing “Communicating with People Who Are Deaf or Hard of Hearing in Hospital Settings.” The primary outcome was healthcare provider cultural competency, measured as a mean score on a scale ranging from 9 to 63, with higher scores indicating higher cultural competency. The primary assessment was post-intervention, up to one month, among enrolled participants who reviewed their assigned intervention and completed the simulation session.

The registry lists five outcome measures and 15 analyses, and reports zero serious adverse events, zero other adverse events, and zero deaths in the listed group entries. Primary and secondary outcome results, analysis details, and missing-data methods are not reported in the registry record.