Daily Living Skills Intervention for 9th and 10th Graders With Autism Spectrum Disorders: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Daily Living Skills Intervention for 9th and 10th Graders With Autism Spectrum Disorders (NCT03984513), a randomized na study. The primary outcome is Vineland Adaptive Behavior Scales, 3rd Edition.

2. Clinical Question

The study is framed as a preliminary test of STRW against an active social skills intervention, rather than against no intervention. This means the intended comparison concerns two behavioral programs with different stated emphases: daily living skills for STRW and social skills for PEERS. The registry record does not report an efficacy result that answers whether scores differed between the groups or changed over time.

The target population is described in more than one way in the registry record: the trial title names 9th and 10th graders, and the brief summary describes adolescents aged 14-21 years with high functioning ASD. Those descriptions can be reported, but further eligibility details are not reported in the registry record. The population field for the primary outcome is blank. Accordingly, the stated question should not be taken to establish how widely any finding would apply beyond the described participants.

3. Trial Design

The registry record describes a randomized, single-masked, parallel-group trial. Participants were assigned to STRW, the daily living skills intervention, or PEERS, the social skills intervention. A parallel design compares separate groups assigned to different interventions; participants are not described as crossing from one intervention to the other. The record identifies masking as single but does not report which people involved in the trial were masked.

The registered enrollment is 58. The brief summary describes a planned evaluation in 56 adolescents. These are distinct statements in the registry record: one is the enrollment figure and the other appears in the study description. The record does not explain the difference. The registry status is completed, with a start date of 2018-09-25 and a primary completion date of 2022-02-28.

The study is described as an ORBIT Phase 2b feasibility randomized clinical trial intended to refine STRW and examine its preliminary effectiveness. The listed phase is NA. These details describe the study's stated purpose and registry classification; they do not establish what results were observed or how the investigators analyzed them.

The primary measure is listed at baseline and post-group, approximately 3 months. The registry record does not specify the number or length of intervention sessions, how assignment was generated or concealed, or the precise masking arrangements. It also does not report a statistical analysis plan, a sample-size justification for the trial, or how the planned enrollment was selected. Those design details should not be inferred from the randomized label or from the study's stated feasibility purpose.

The sponsor is Children's Hospital Medical Center, Cincinnati. The registry record lists a behavioral intervention in each arm and one primary outcome measure. Although the primary measure is named, the record does not reduce its multiple measurement occasions to one treatment comparison, and no analysis is listed. Thus, the design information establishes the broad comparison and timing, but not a complete account of how the primary question was to be analyzed.

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: We had several screen fails, which we compensated for by enrolling above our target number for completion.

Overall 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.

6. Primary Endpoint

The registry lists the primary outcome as Vineland Adaptive Behavior Scales, 3rd Edition, measured over At Baseline, at Post-Group (approx. 3 months).

The primary outcome is the Vineland Adaptive Behavior Scales, 3rd Edition (VABS-3), a standardized measure of adaptive behavior. Its domains include Communication, Daily Living Skills, and Socialization. The Daily Living Skills domain includes Personal, Domestic, and Community subdomains, with items that directly correspond to goals targeted by STRW. The registry record describes raw scores for that domain as ranging from 0 to 286 and states that higher scores indicate a better adaptive level.

The measure is relevant to the intervention's stated focus because it assesses everyday adaptive skills, including the daily living domain targeted by STRW. The registry record lists the outcome as a mean with standard deviation and gives the timeframe as baseline and post-group, approximately 3 months. A standardized measure can provide a consistent way to assess behavior across participants, while the subdomains help describe distinct aspects of adaptive functioning.

The outcome's measurement description does not itself establish that STRW changes the score, or that a score difference would be clinically important. The registry record does not report a threshold for meaningful change, arm-specific means, standard deviations, changes from baseline, or a statistical comparison. It also does not identify one occasion or one contrast as the sole primary analysis. The endpoint is therefore defined in terms of what is measured and when, but its observed results are not reported in a form that answers the treatment comparison.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes randomized allocation and a parallel-group model. In general, randomization is used to make assigned groups comparable on average with respect to measured and unmeasured characteristics, although chance differences can remain. A parallel design keeps participants in their assigned intervention group for the comparison. These design features define the broad structure of the trial, but do not tell readers how allocation was generated, whether it was concealed, or how participants were handled after assignment. Those details are not reported in the registry record.

What is the outcome scale?

VABS-3 is described as a standardized measure of adaptive behavior. The registered primary outcome is a mean on a continuous measure, with standard deviation as the dispersion summary. A continuous outcome can take values along a scale rather than being limited to event categories. The Daily Living Skills domain has raw scores ranging from 0 to 286, and higher scores are described as indicating a better adaptive level. This direction gives a basis for interpreting a score, but the record does not report actual scores or a comparison between groups.

The mean is an average that can summarize a group, while the standard deviation describes variation among scores within that group. The standard deviation is not the uncertainty in the estimated mean or in a treatment contrast. To quantify uncertainty in a comparison, an analysis would ordinarily report an effect estimate with an interval or another inferential measure. No such primary outcome estimate is listed in the registry record.

What comparison would answer the question?

Because the measure is listed at baseline and post-group, approximately 3 months, more than one possible contrast could be considered. A comparison of post-group means asks how the groups differ at that assessment. A comparison of changes asks how much each group's scores changed from baseline and then contrasts those changes. An analysis that adjusts for baseline scores asks a related question while accounting statistically for initial measurement. These are general approaches, not descriptions of the analysis used in this trial: the specific primary contrast and model are not reported in the registry record.

The registry identifies one primary outcome measure, but gives more than one measurement occasion and does not reduce these to one comparison. The record's note says the primary outcome has several categories or time points and is not reduced to one comparison. It lists zero analyses. Thus, there is no reported estimate, standard error, confidence interval, test statistic, or p-value for a single efficacy contrast to interpret.

How should uncertainty be understood?

In general, an effect estimate is the numerical summary of a comparison, such as a difference in average scores. A confidence interval expresses the range of values reasonably compatible with the data and the analysis assumptions. A narrow interval indicates greater precision than a wide interval, while an interval spanning effects in opposing directions can leave the direction uncertain. These concepts do not yield a trial-specific conclusion without a reported estimate and interval. Neither is reported for the primary outcome in the registry record.

A p-value, in general, summarizes how unusual data at least as incompatible with a specified null hypothesis would be if that hypothesis and the test assumptions held. It does not measure the size or practical importance of an effect. The registry record does not list a primary outcome p-value or its analysis, so no significance claim can be assessed.

What does the planning information mean?

The record describes planning illustrations based on an observed effect, using a two-sided significance level of 0.05, equal allocation between the two arms, and a normal approximation. The stated effect to detect is a fraction of the observed effect. Such illustrations are hypothetical planning calculations, not outcomes observed in participants and not observed power. They depend on assumptions about the target effect and analysis. The registry does not report a trial-specific sample-size justification. In addition, because the primary outcome is not reduced to one comparison, the planning assumptions do not establish which outcome contrast a reader should treat as definitive.

In general, power planning concerns the probability that a specified analysis would detect a chosen effect under specified assumptions. It does not determine whether an effect occurred, nor does it replace an estimate with its uncertainty. The registry record's planning description should therefore be kept separate from the trial's observed efficacy results, which are not reported as a comparison.

What can be said about analysis choices?

A statistical analysis plan would ordinarily clarify the outcome contrast, handling of baseline measurements, analysis population, missing-data approach, and any adjustments for multiple testing. The registry record does not report those choices. It also does not specify whether the primary analysis would follow assigned groups, how protocol deviations would be treated, or whether any covariates would be included. These are not details that can be reconstructed from the outcome name or randomized design.

In general, over-dispersion refers to variability greater than an analysis model expects; it can make standard errors too small if the model does not account for the extra variability. This concept is particularly relevant to some count outcomes. The registered primary outcome is a continuous score summarized by a mean and standard deviation, and no trial-specific model or over-dispersion issue is reported. A general explanation of statistical concepts cannot fill in an unreported analysis plan.

10. Multiplicity, Missing Data and Analysis Populations

The record lists one primary outcome measure, but gives baseline and post-group, approximately 3 months, as measurement occasions. It also indicates that the primary outcome has several categories or time points and is not reduced to one comparison. As a result, the record does not identify one primary contrast among the listed measurement occasions. The number of analyses listed is zero.

Multiplicity arises in general when investigators make several statistical comparisons: the more opportunities to find an apparently unusual result, the greater the chance of at least one such result under a null hypothesis. Analysis plans can address this through prespecified primary comparisons or statistical adjustments. The registry record does not report a multiplicity strategy, a hierarchy of comparisons, or whether any adjustment was planned. It is therefore not possible to determine how multiple assessments or domains were handled statistically.

Missing-data methods are also not reported in the registry record. The enrollment figure does not establish how many participants completed each assessment or contributed to an outcome analysis. The record does not describe withdrawals, incomplete questionnaires, imputation, or sensitivity analyses. These omissions matter because a comparison based on incomplete outcome data can depend on who remains observed and on assumptions about unobserved scores.

The analysis population is not reported. In general, an analysis based on assigned groups preserves the comparison created by randomization, while other approaches may include different participant subsets or require additional assumptions. The record does not say which approach was used or planned, nor how deviations from the assigned intervention were handled. These are limits on interpretation, not evidence that any particular method was or was not used.

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 lists serious adverse events, other adverse events, and deaths for each intervention group. For STRW, the listed figures are 0 serious adverse events among 26 at risk, 0 other adverse events among 26 at risk, and 0 deaths. For PEERS, the corresponding figures are 0 serious adverse events among 22 at risk, 0 other adverse events among 22 at risk, and 0 deaths. No top serious adverse event terms are listed.

These are counts within the safety groups recorded in the registry. A count of zero means no event of that category was recorded in the listed group; it does not demonstrate that the underlying risk is zero. The registry record does not provide event descriptions, exposure time, or further detail on how adverse events were collected. The figures should therefore be read as descriptive reporting, not as a precise estimate of comparative safety.

The safety information does not answer the primary efficacy question about VABS-3 scores. Nor do the counts establish that all possible harms were assessed or reported. They describe the event categories and at-risk counts recorded for the two arms, without supporting a broader conclusion beyond those entries.

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

The registry record describes a randomized trial comparing STRW, a daily living skills intervention, with PEERS, a social skills intervention, in adolescents with autism spectrum disorder. It identifies VABS-3 as the primary outcome measure and specifies baseline and post-group, approximately 3 months, as measurement occasions. The Daily Living Skills domain is particularly relevant to STRW's stated targets, and higher raw scores are described as indicating a better adaptive level.

Those design details explain what the investigators set out to compare, but they do not establish the result. The registry record does not report arm-specific primary outcome scores, a change estimate, a between-group contrast, a confidence interval, or a p-value. The primary outcome is not reduced to one comparison, and no analysis is listed. There is therefore no reported numerical efficacy result from which to infer the direction, size, or precision of a difference between the interventions.

The registered enrollment of 58 and the brief summary's description of 56 adolescents should not be mistaken for analysis counts. The record does not explain the difference or report how many participants contributed outcome data at each assessment. It also does not report the analysis population, missing-data method, or primary statistical model. Those details would be needed to understand how a treatment estimate was constructed and how robust it might be.

Likewise, a completed trial status is not an efficacy finding. The recorded zero adverse event and death counts describe the reported safety categories and groups, but do not answer whether the primary scores differed. The planning description is hypothetical and is not evidence of a treatment effect.

The defensible conclusion is limited: the registry defines a randomized behavioral-intervention comparison and a relevant adaptive-behavior measure, but does not report the numerical primary outcome analysis needed to judge the comparison. The record does not support a claim that one intervention produced better scores, nor does it establish equivalence or absence of an effect.

13. Why This Trial Matters Statistically

This trial illustrates why outcome definitions and outcome results must be kept distinct. VABS-3 is specified as a standardized adaptive-behavior measure, and the Daily Living Skills domain aligns with the stated focus of STRW. That alignment makes the endpoint relevant to the intervention's purpose, but relevance does not substitute for a reported treatment estimate. Without arm-specific scores and a defined contrast, readers cannot assess the magnitude or precision of a difference.

The record also illustrates the importance of prespecifying how repeated measurements will answer a single primary question. Baseline and post-group assessments provide a structure for examining outcomes over time, but post-group scores, changes from baseline, and baseline-adjusted comparisons are not interchangeable. The record does not specify which was intended as the primary analysis. Clear reporting of the contrast, model, and analysis population would make interpretation more reproducible.

For a randomized trial, the analysis should connect assignment to outcome measurement in a transparent way. Reporting how many participants contributed data at each assessment, how missing scores were handled, and whether analyses followed assigned groups helps readers judge potential bias and uncertainty. Those details are not reported in the registry record. Their absence is especially consequential when the record gives enrollment figures but not outcome-analysis counts.

Finally, planning calculations and observed results have different roles. Planning assumptions can illustrate what sample sizes might be needed for selected effects under specified methods; they cannot show what happened in a completed trial. A statistical interpretation requires the observed effect and its uncertainty. This record establishes the study question and broad design, but the missing primary analysis prevents an evidence-based quantitative interpretation of the comparison.

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.

A central limitation of interpretation is that the registry record does not report numerical primary outcome results. Although it names VABS-3 and the baseline and post-group measurement occasions, it provides no group means, standard deviations, changes, or treatment contrast. It also lists no analyses and does not reduce the multiple occasions to one comparison. The direction and precision of any efficacy difference are therefore not assessable from the record.

The record does not report the statistical analysis plan, including the primary contrast, model, handling of baseline scores, or analysis population. Missing-data procedures and numbers contributing outcome data at each assessment are also not reported. Without those details, readers cannot assess whether the analyzed participants would preserve the balance intended by randomization or how incomplete measurements may affect an estimate.

There is a difference between the registered enrollment of 58 and the brief summary's description of a trial in 56 adolescents; the reason is not reported in the registry record. The title specifies 9th and 10th graders, while the summary describes participants aged 14-21 years with high functioning ASD. Further eligibility criteria and the relationship between these descriptions are not reported.

Masking is recorded as single, but the identity of the masked parties is not reported. The record also does not report allocation concealment, intervention adherence, or protocol deviations. The listed safety counts are descriptive and do not provide detailed event information or exposure time. These limitations restrict interpretation of both efficacy and safety beyond the specific registry entries.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Daily Living Skills Intervention for 9th and 10th Graders With Autism Spectrum Disorders — NCT03984513.
• Registry record last updated 2023-06-27; status last verified 2023-06.
• Results first posted 2023-06-27.
• 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

NCT03984513 is a completed randomized, single-masked, parallel-group trial sponsored by Children's Hospital Medical Center, Cincinnati. It compares STRW, a daily living skills intervention, with PEERS, a social skills intervention, for adolescents with autism spectrum disorder. The registered enrollment is 58; the brief summary describes 56 adolescents. The listed phase is NA.

The primary outcome is VABS-3, recorded as a mean with standard deviation at baseline and post-group, approximately 3 months. The Daily Living Skills domain raw-score range is 0 to 286, with higher scores indicating a better adaptive level. The registry record does not report a single primary comparison or an efficacy analysis. Safety entries list 0 serious adverse events, 0 other adverse events, and 0 deaths in each group, with at-risk counts of 26 for STRW and 22 for PEERS.