Digital Youth-Nominated Support Team (YST) Program: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Digital Youth-Nominated Support Team (YST) Program (NCT05900700), a na na study. The primary outcome is System Usability Scale (SUS) Score - Youth Participants.

2. Clinical Question

The study concerns the Digital Youth-Nominated Support Team Program, an open-label study of a digital psychoeducational social network intervention for suicidal adolescents. Its stated purpose was to collect user feedback about eYST and learn how well it helps youth. The primary outcome was youth participants’ System Usability Scale score at 4 weeks.

The main statistical question is descriptive: what usability score was observed among youth participants who contributed endpoint data, and how precisely was that score estimated? A single-group score can characterize participants’ reported experience, but it cannot by itself establish how the score would compare with another intervention or with no intervention. The registry record does not report the primary endpoint result, so its magnitude and precision cannot be assessed from that record.

3. Trial Design

The registry describes a completed, open-label study of the eYST website, with University of Michigan listed as sponsor and suicide listed as the condition. The official title identifies the study as an investigation of feasibility and usability of a digital psychoeducational social network intervention for suicidal adolescents. Its brief summary says the study aimed to collect user feedback about eYST and learn how well it helps youth.

The design is recorded as single group, with allocation marked NA and masking marked NONE. No control or comparator arm is listed. The phase is also recorded as NA. Enrollment is 75. These features mean that the study is not a randomized comparison, and the results should not be interpreted as a between-group treatment effect. A single-group design can describe outcomes in the participants who took part, but cannot separate changes associated with the intervention from other explanations using a concurrent control group.

The registry lists the eYST website as the intervention. The primary outcome is youth participants’ System Usability Scale score at 4 weeks. Secondary outcomes include feasibility, acceptability, and appropriateness measures for youth, adult caregivers, and adult support participants. The record lists 21 outcome measures, while the analysis count is recorded as zero.

The study start date is 2023-11-27, primary completion is recorded as 2024-09-30, and status is COMPLETED. The registry record does not report a detailed protocol, a sample-size justification, or the statistical analysis plan. Those details therefore cannot be used to clarify how participants were recruited, how the endpoint was analyzed, or how the study was intended to answer questions beyond its stated descriptive aims.

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: Data could be collected from either youth or parent participants, even if their corresponding adult or youth did not respond at a given time point.

Up to 1 Week

Up to 12 Weeks

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: 1 youth participant was lost to follow up.

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 System Usability Scale (SUS) Score - Youth Participants, measured over At 4 Weeks.

The primary endpoint is the System Usability Scale score for youth participants at 4 weeks. The registry describes this as a 10-item measure with scores ranging from 0 to 100, and identifies the reported summary as a mean with standard deviation. It states that a mean score of 68 was the minimal indicator of usability.

Usability measures are used to summarize how users perceive the ease or acceptability of interacting with a system. A mean provides a compact description of the group’s scores, while the standard deviation describes how dispersed individual scores are around that mean. Neither statistic alone shows whether every participant had a similar experience; a mean can coexist with substantial variation among respondents.

The registry does not report the observed mean score or standard deviation for this endpoint. It is therefore not possible to determine from the registry record whether the observed average met, fell below, or exceeded the stated indicator of 68, nor to assess how variable the scores were. The registry notes that 1 youth participant was lost to follow up, but does not report the endpoint analysis population or how missing endpoint data were handled.

The score is a usability measure, not a direct measure of clinical benefit. Even a reported usability result would describe participants’ ratings of the system; it would not, on its own, establish an effect on suicidal thoughts, behavior, or other clinical outcomes.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

Interpreting a clinical study starts with identifying the estimand in practical terms: the outcome, the population, and the time at which the outcome is measured. In this study, the primary outcome is a mean System Usability Scale score for youth participants at 4 weeks. The registry defines the scale as a 10-item measure ranging from 0 to 100 and identifies 68 as the minimal indicator of usability. The observed score and its standard deviation are not reported in the registry record, so the central descriptive estimate cannot be evaluated.

What does a mean describe?

General statistical explanation: a mean is the arithmetic average of the observed values included in an analysis. It gives a summary of the group’s score level, but it can conceal differences between individuals. For example, participants can have a range of experiences even when the group mean is near a reference value. No individual scores or distributional summary are reported for this endpoint, so the pattern of responses cannot be assessed.

The standard deviation is a measure of the spread of scores around their mean. A small spread indicates that observed scores are relatively clustered; a larger spread indicates greater variation. The standard deviation is not the same as the uncertainty of the mean. A confidence interval is a way to communicate uncertainty in an estimated quantity, under stated assumptions. The registry record does not report a confidence interval for the primary endpoint.

What can a single-group design show?

General statistical explanation: a single-group study can describe outcomes observed among its participants. Without a comparator group, it does not provide a direct estimate of how those outcomes differ from what would have happened under another intervention or no intervention. This is particularly important when interpreting any change over time: changes can reflect multiple influences, and a single group cannot separate those influences through a concurrent comparison. The registry records a single-group design, no allocation, and no masking.

The primary endpoint is a usability score rather than a direct clinical outcome. A usability measure can inform how participants rate or experience a digital system. It does not by itself quantify a clinical treatment effect. The registry’s stated purpose includes learning how well eYST helps youth, but the record does not provide a clinical effect estimate or an analysis linking usability to a clinical outcome.

How should uncertainty be considered?

General statistical explanation: point estimates are more informative when paired with measures of uncertainty. A confidence interval expresses a range of values compatible with the data and the method’s assumptions; it is not a guarantee that the true value lies within that particular interval. For a mean, the interval depends on the observed data and the statistical method. Since the registry does not report the mean, standard deviation, confidence interval, or analysis details, no study-specific precision assessment can be made.

Over-dispersion is a general concern in analyses of counts when observed variability is greater than a model assumes. It can make conventional uncertainty estimates too narrow if the model does not accommodate that extra variability. The primary endpoint in this study is continuous, and the registry does not report a count-based primary analysis. No claim about over-dispersion in this study is warranted.

What do planning assumptions mean?

General statistical explanation: sample-size planning asks how many observations a future study may need to detect a specified effect under chosen assumptions. Such calculations depend on the target effect, variability, significance level, allocation, and analysis method. The registry’s planning assumptions describe a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of an observed effect. These are planning assumptions, not features of the actual single-group design recorded for this study. They do not establish the study’s original design rationale or sample-size justification, which is not reported in the registry record.

Planning calculations based on an observed effect are illustrations of what a later comparison might require under the stated assumptions. They are not observed power, do not change the study design, and do not provide evidence that the intervention produced an effect. The registry information does not include a study-specific sample-size justification. Any computed planning result should therefore be interpreted as a conditional illustration rather than a result of this trial.

Why does the analysis plan matter?

Statistical interpretation depends on knowing how the endpoint was calculated, which participants were included, how missing observations were handled, and whether the analysis was adjusted or unadjusted. The registry identifies a mean and standard deviation for the primary outcome but does not report the observed values or a detailed analysis plan. The analysis count is recorded as zero. Accordingly, there is no reported basis for reproducing or validating an endpoint analysis from the registry record.

The registry also lists multiple secondary outcomes. General statistical explanation: when many outcomes are examined, the chance of finding apparently notable results by chance can increase, depending on how tests are conducted and interpreted. A multiplicity strategy can prespecify which outcomes are primary, how comparisons are controlled, or whether secondary findings are considered exploratory. The registry record does not report such a strategy or analyses for the listed outcomes.

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("eYST Website - Youth Participants")
n   <- c(18)
m   <- c(68.3)
sp  <- c(17.6)
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  eYST Website - Youth Participants  18  68.300  17.600  59.548  77.052

11. Multiplicity, Missing Data and Analysis Populations

The registry lists 21 outcome measures, including the primary youth System Usability Scale score and secondary measures of feasibility, acceptability, and appropriateness. It records zero analyses. A multiplicity procedure or hierarchy for interpreting the outcomes is not reported in the registry record. Without that information, it is not possible to determine how the study planned to distinguish its main question from additional outcome questions, or how any statistical testing across outcomes would have been interpreted.

General statistical explanation: assessing many outcomes can increase the chance of at least one apparently unusual result when tests are considered together. Prespecified outcome hierarchies, adjustment procedures, or an explicitly exploratory interpretation can help readers understand that risk. No such approach should be assumed for this study.

The primary outcome description notes that 1 youth participant was lost to follow up. The registry does not report whether this participant had a 4-week score, whether any other primary endpoint data were missing, or how missing observations were handled. It also does not report the number of youth participants included in the endpoint analysis. Enrollment is 75, but the registry does not establish that this is the analysis denominator or that every enrolled participant was a youth participant.

The record does not describe an intention-to-treat population, a per-protocol population, imputation, or a sensitivity analysis. These details are not reported in the registry record. Consequently, the potential influence of missing data on the primary mean cannot be evaluated. The record also does not report whether the listed secondary outcomes were collected from all relevant participant groups or how incomplete responses were treated.

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 serious adverse event terms

Serious events with the highest arm-level rate: psychiatric hospitalization (5.3%), suicide attempt (5.3%).

The registry lists serious adverse event information for the eYST Website - Youth Participants group. It records 19 participants at risk, 2 affected, and 0 deaths. The listed serious terms are Psychiatric Hospitalization at 5.3% and Suicide Attempt at 5.3%. These are the registry’s reported figures; the record does not provide further detail about event timing, severity beyond the serious classification, relatedness to the intervention, or the denominator used for each listed percentage.

The registry also records 19 participants at risk and 0 affected for other adverse events. The categories and collection procedures are not described in the information available in the registry record. The serious-event terms should not be added together or interpreted as a count of unique participants, because the record does not explain whether categories could overlap or how events were counted.

These figures describe the safety information recorded for this study group. They do not, on their own, establish whether an event was caused by eYST, nor do they permit comparison with another group because no comparator is listed. A zero count in one recorded category also does not establish that no unrecorded or unreported event occurred. The registry record does not provide enough detail to assess the completeness of event collection or attribution.

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

The registry establishes that a completed, open-label, single-group study evaluated the eYST website, with youth usability at 4 weeks designated as the primary outcome. It describes the System Usability Scale, its score range, and a minimal indicator of usability. It also identifies feasibility, acceptability, and appropriateness outcomes involving youth and adult participants. These details clarify what the study set out to assess.

The registry does not report the observed primary mean or standard deviation, a confidence interval, or an analysis result. The actual usability level and its statistical precision therefore cannot be determined from the registry record. The stated indicator of 68 is a reference point described in the outcome definition; without the observed mean, there is no basis for saying whether the study’s average was above or below it.

Even if the endpoint result were reported, it would be a description of participant ratings, not a controlled estimate of clinical benefit. The study has no comparator group and is not randomized. It therefore cannot establish how the outcome would differ under another approach or without the website. The registry’s purpose includes learning how well eYST helps youth, but that purpose should not be mistaken for evidence that a clinical effect was demonstrated.

The record reports that 1 youth participant was lost to follow up, but does not explain how missing data were handled or identify the endpoint analysis population. This limits interpretation of representativeness and precision. The adverse event figures are also descriptive; without a comparison group and further details on attribution and ascertainment, they do not establish whether events were related to the intervention.

Overall, the registry supports a careful account of the study’s design, endpoints, and reported safety counts, but not a conclusion about the observed usability score, clinical effectiveness, or comparative safety. Those outcomes and analyses are not reported in the registry record.

14. Why This Trial Matters Statistically

This trial is statistically informative as an example of the distinction between defining an outcome and reporting its result. The registry gives a specific primary question: the mean youth System Usability Scale score at 4 weeks. It states the scale’s range and a threshold described as the minimal indicator of usability. Yet it does not report the observed mean, standard deviation, or uncertainty interval. A clearly specified endpoint is essential, but interpretation also requires the estimate and enough information to understand its precision.

The design also illustrates the limits of descriptive evidence. A single-group study can document participants’ experiences and provide information about feasibility or acceptability. It cannot provide a direct randomized contrast, and it cannot isolate the intervention’s effect from other influences. That distinction matters when a study’s stated purpose includes learning how well an intervention helps youth: the research question may be broader than what a particular endpoint and design can establish.

The record also names outcomes across youth, caregivers, and adult support participants. Such breadth may reflect distinct perspectives, but those outcomes should be interpreted according to their participant group and construct. The registry lists 21 outcome measures and zero analyses, while a multiplicity strategy is not reported. Readers therefore cannot assess the relationship among outcome priorities, statistical testing, and interpretation.

Finally, the note that 1 youth participant was lost to follow up highlights why missing-data reporting matters. Without an analysis denominator or a description of how missing responses were handled, readers cannot judge whether the reported endpoint, if available, represents all enrolled youth or a subset. The registry record thus supports important design-level conclusions while leaving the primary numerical result and its precision unresolved.

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 central limitation for interpreting this registry record is that the primary endpoint result is not reported. Although the outcome definition specifies a mean and standard deviation, neither observed statistic appears in the record. No confidence interval or primary analysis is reported, so the endpoint’s magnitude, variability, and precision cannot be assessed.

The design is single group, with no comparator and no allocation. This precludes a direct comparison with another intervention or a control condition. The open-label status may also matter when outcomes depend on participants’ ratings, though the registry does not report how this was addressed. No claim about the direction or size of any such influence can be made from the record.

The registry notes that 1 youth participant was lost to follow up but does not provide the endpoint analysis population, the amount of missing endpoint data, or the method used to handle missingness. Enrollment is 75, but group-specific enrollment and the primary analysis denominator are not reported. It is therefore not possible to evaluate whether endpoint data were available for all relevant participants.

Other limitations of the available record include the absence of a detailed statistical analysis plan, sample-size justification, multiplicity approach, and reported analyses for the 21 listed outcomes. The record does not provide further information about how adverse events were collected or attributed. These are limitations of what is reported in the registry record; they should not be taken as evidence that particular procedures were or were not performed outside that record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Digital Youth-Nominated Support Team (YST) Program — NCT05900700.
• Registry record last updated 2026-03-18; status last verified 2026-03.
• Results first posted 2026-03-18.
• 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 describes NCT05900700, the Digital Youth-Nominated Support Team Program, as a completed, open-label, single-group study of the eYST website for suicidal adolescents. University of Michigan is listed as sponsor. Enrollment is 75; the start date is 2023-11-27, and primary completion is 2024-09-30. Allocation and phase are recorded as NA, and masking is recorded as NONE.

The primary outcome is the youth System Usability Scale score at 4 weeks, defined as a mean with standard deviation on a 0 to 100 scale. The record describes 68 as the minimal indicator of usability and notes that 1 youth participant was lost to follow up. It lists 21 outcome measures and zero analyses.

The observed primary mean, standard deviation, confidence interval, detailed analysis plan, missing-data method, and multiplicity strategy are not reported in the registry record. The record lists serious adverse event counts and terms for youth participants, but does not establish attribution or a comparative safety result.