Veteran Support and Resources for Diabetes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Veteran Support and Resources for Diabetes (NCT04041375), a randomized na study. The primary outcome is Change in Diabetes Distress Screening Scale (DDS17).

2. Clinical Question

The study asks whether a telephone-based peer coaching program can improve Veterans’ physical and emotional health more than a directory of VA and community resources with encouragement to follow up with a primary care physician. The primary outcome named in the registry is change in diabetes-related distress. The record describes the intervention as peer coaching by a Veteran with knowledge of diabetes, mental health and community resources, intended to help participants connect with VA or community care according to their preferences.

This is a question about a comparison between assigned study approaches, not a test of whether any particular resource was used or whether one individual resource caused an outcome. The registry also lists secondary outcomes concerning diabetes self-care, smoking, depressive symptoms, anxiety symptoms and use of community resources. The primary outcome remains the DDS17 change measure.

3. Trial Design

The registry describes a randomized, double-masked, parallel-group study of Veterans with diabetes. The listed interventions are iNSPiRED, a peer coaching intervention, and Usual Care, a directory of resources with encouragement to follow up with a primary care physician. Enrollment is reported as 219. The study status is completed. The recorded start date is 2019-10-01, and the primary completion date is 2022-08-09.

In a randomized parallel design, participants are assigned to an intervention arm and the comparison is made between the groups over the study period. Random assignment can help balance measured and unmeasured characteristics on average, although it does not guarantee balance in any particular study. The registry reports randomization; details of the sequence generation, allocation concealment and implementation are not reported in the registry record.

The registry labels the study double-masked but does not specify which people were masked or how masking was maintained. That detail matters when interpreting participant-reported measures: knowledge of assignment could affect reporting or assessment, but whether and how this possibility was addressed is not reported in the registry record. The study model is parallel rather than a crossover design, so the posted description does not indicate that participants switched between the approaches.

The intervention is described as telephone-based coaching from a Veteran familiar with diabetes, mental health and community resources. The comparison arm receives a directory and encouragement to follow up with primary care. The registry does not report the frequency or duration of coaching, the degree of intervention completion, or the amount of resource use. Those details would help characterize what participants actually received and whether the planned contrast was achieved.

The record identifies diabetes as the condition and describes the target group as Veterans with diabetes-related distress. It does not give additional eligibility criteria, recruitment locations, demographic characteristics or details of usual care beyond the directory and encouragement to follow up. The phase is listed as NA. These omissions limit how fully the study population and the delivery context can be characterized from the registry record alone.

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: One participant who provided informed consent withdrew prior to completing baseline/randomization.

Intervention Phase

Reasons for not completing this period:

Follow-up Phase

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: Full sample

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 Change in Diabetes Distress Screening Scale (DDS17), measured over Baseline, Month 3, Month 6.

The primary endpoint is change in the Diabetes Distress Screening Scale, identified as DDS17. Diabetes distress refers to emotional and practical strain related to living with and managing diabetes. The registry says the instrument was developed with input from people with diabetes and clinicians with relevant expertise. It organizes items into four subscales: Emotional Burden, Physician-related Distress, Regimen-related Distress and Interpersonal Distress.

Each item is rated from 1, meaning no problem, to 6, meaning a serious problem. The total score and subscale scores are calculated as averages across their respective items. The minimum total score is 1 and the maximum is 6; higher scores indicate worse distress. The listed primary outcome is change in the total DDS17 score, with measurement at baseline, Month 3 and Month 6.

A distress measure is relevant to this intervention because peer navigators are intended to help participants connect with health and community resources while addressing diabetes-related stress. That rationale does not establish that the measure changed or that any change was caused by coaching. The registry record does not report the numerical primary outcome results, the definition used to calculate change, or a single contrast across the listed time points. Those details are needed to judge the magnitude and precision of the primary comparison.

As a general measurement point, an average score preserves the scale’s units and provides a concise summary of responses, but it can conceal differences across subscales or participants. A change score describes movement between assessments; its meaning depends on the comparison, the time point and the analysis approach. The registry’s outcome description explains scoring and direction but does not report an interpretation threshold for a clinically important change.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry establishes the broad design and identifies the primary measure, but it does not provide a full statistical analysis plan or a numerical primary comparison. The following explanations are general statistical context; they should not be read as claims that a particular method was used in this study unless it is explicitly identified in the registry record.

What does the mean summarize?

The DDS17 is described as a continuous score formed by averaging item responses. A mean summarizes the center of a set of scores, while a standard deviation describes how spread out the scores are around that mean. The registry identifies the primary outcome’s parameter as a mean and its dispersion as a standard deviation. Those summaries can help describe the distribution within each arm, but they do not by themselves establish a between-arm effect. To answer the comparative question, the reader needs an estimate that directly contrasts the arms and a measure of its uncertainty.

A change outcome also requires a clear definition. It may refer to a difference between a follow-up value and baseline, or to a model-based contrast that uses measurements from more than one time point. Those approaches can yield different estimates and precision. The registry lists baseline, Month 3 and Month 6, but does not report how change was calculated or which time-point contrast was used for the primary analysis.

Why does uncertainty matter?

General statistical interpretation uses a confidence interval to show a range of estimates compatible with the observed data under the method’s assumptions. A narrow interval indicates greater precision than a wide interval, while an interval that includes values on both sides of a no-difference value may leave the direction or size uncertain. A p-value addresses compatibility with a specified null model; it does not measure the probability that the null hypothesis is true, the clinical importance of an effect, or the chance that the result will replicate. The registry record does not report a primary confidence interval or p-value, so these features cannot be assessed for this comparison.

Randomization supports comparison of assigned groups by reducing systematic differences in expectation, but analysis still matters. For example, an analysis based on assigned groups generally preserves the original randomized comparison, whereas an analysis based on treatment received can be affected by post-randomization differences. The registry record does not report the primary analysis population or whether analyses followed assignment regardless of intervention participation.

How can repeated measurements be handled?

When an outcome is recorded at multiple visits, an analysis can compare groups separately at each time point, estimate an overall group difference across follow-up, or examine whether changes over time differ between groups. These choices address related but non-identical questions. Repeated observations from the same participant are correlated; treating them as independent can misstate uncertainty. General methods for repeated measurements account for that within-participant relationship, but the registry record does not identify a repeated-measures model or other method used for the DDS17.

Missing follow-up values can also affect repeated-measure analyses. General approaches make assumptions about why data are missing and how the observed values relate to the unobserved ones. A complete-case analysis, for instance, uses participants with the needed observations, while other approaches may use partial data or imputation. Each approach has assumptions and possible limitations. The registry record does not describe missingness, imputation, sensitivity analyses or the number of participants contributing DDS17 data at each assessment.

What does multiplicity change?

The registry lists 13 outcome measures and 34 analyses. In general, examining multiple outcomes, time points and contrasts creates multiple opportunities for a result to appear statistically notable by chance. A prespecified hierarchy or adjustment can help define how findings should be interpreted, but there is no universal method that can be inferred solely from the number of analyses. Whether outcomes were prespecified, which comparisons were primary within secondary outcomes, and whether any adjustment was made are not reported in the registry record.

How should planning illustrations be read?

The stated planning assumptions describe illustrations based on the observed effect, with a two-sided significance level of 0.05, equal allocation between arms and a normal approximation. The stated effect to detect is a fraction of the observed effect. Such illustrations address how many participants per arm might be needed under those assumptions; they are not observed treatment effects and are not observed power. They do not show that the trial was originally designed using those assumptions. The registry record does not report the trial’s own sample-size justification or statistical plan. No planning value should be interpreted as an outcome estimate.

The general lesson is to separate design information, descriptive summaries, comparative estimates and uncertainty. The registry describes randomization, masking, the parallel model and the scale. It does not provide enough analysis detail to reconstruct the primary estimate or verify which statistical procedures were used. That distinction is essential: a method that is reasonable in general cannot be attributed to this trial without documentation in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists 13 outcome measures and 34 analyses. This indicates that the results span more than the single primary outcome and involve multiple analyses. As a general statistical concern, the more outcomes, time points and comparisons examined, the more important it is to know which analyses were prespecified and how the family of tests was handled. A multiplicity procedure can change how evidence is assessed across a set of comparisons; the registry record does not report whether one was used.

The primary outcome itself is described at baseline, Month 3 and Month 6, and the registry notes that it has several categories or time points rather than one reduced comparison. The record does not identify a single primary contrast across those assessments. It also does not report the prespecified order or priority of secondary analyses, or whether the secondary measures were exploratory or confirmatory. These omissions make it difficult to distinguish the central planned test from findings considered among a broader set of analyses.

Missing-data information is also not reported in the registry record. The number of participants with an observed DDS17 score at each assessment, reasons for missing assessments, and the statistical handling of missing values are not stated. Missing observations can affect both the estimated group difference and its precision, particularly when missingness is related to participant characteristics or outcomes.

The analysis population is not reported in the registry record. The record therefore does not establish whether the primary comparison included everyone as randomized, only those with outcome data, or another defined population. Nor does it report sensitivity analyses to examine the effect of missing data or alternative analysis choices. These are reporting limitations, not evidence that a 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.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: hospitalization (2.8%), death (0.9%).

The registry reports serious adverse event counts separately for iNSPiRED and Usual Care. For iNSPiRED, 12 participants are listed as affected among 110 at risk; for Usual Care, 11 are listed as affected among 108 at risk. The registry separately reports 2 deaths in iNSPiRED and 0 in Usual Care. These are counts as recorded, not calculated rates, and they should be interpreted alongside the record’s definitions and reporting period, which are not described in the information available.

The most frequently listed serious-event terms are Hospitalization, at 2.8%, and Death, at 0.9%. The registry also reports other adverse events affecting 1 participant in iNSPiRED and 0 in Usual Care, with 110 and 108 respectively listed as at risk. These counts do not show whether events were related to an intervention, how many events each affected participant experienced, or when events occurred. Causal attribution, event timing and severity details beyond the serious-event classification are not reported in the registry record.

Adverse-event counts in randomized groups are descriptive. The arm counts alone do not establish that an intervention caused an event or that any difference between arms is meaningful. The record does not report a statistical comparison of safety outcomes. The death counts are shown separately from the serious-event affected counts; the registry information does not state how those categories overlap. The available figures should therefore be read as reported safety summaries rather than a causal assessment.

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

This trial is designed to address a practical access question: whether peer coaching can help Veterans with diabetes-related distress connect with VA or community resources more effectively than receiving a directory and encouragement to follow up with primary care. Its primary outcome, change in DDS17 score, focuses on diabetes-related distress rather than resource access alone. The registry also identifies secondary outcomes concerning self-care, smoking, depressive symptoms, anxiety symptoms and community-resource use.

The design information supports describing the intended comparison: randomized assignment, a parallel model and two named study approaches. The record reports enrollment of 219 and completed status. These registry entries establish the broad structure of the study, but they do not reveal how many participants completed each assessment, the extent to which coaching was received, or the magnitude of any outcome difference.

The main boundary on interpretation is that a numerical primary result is not reported in the registry record. The record notes multiple categories or time points and does not reduce the primary outcome to one comparison. Without a comparative estimate and its uncertainty, readers cannot judge the direction or precision of the primary finding. This absence is not the same as a finding of no effect, and it does not establish that the groups were equivalent.

Even if a group difference were available, interpretation would still depend on missing information such as the analysis population, missing-data methods and multiplicity approach. An observed difference would not by itself prove that coaching caused the difference; randomization helps support a causal comparison, but departures from assignment, missing data and measurement issues can influence interpretation. The registry record does not provide enough detail to assess those possibilities.

Nor does the study description show that every participant used a resource or received the same amount of coaching. The program is intended to support connection to services according to preference, while the comparator receives a directory for independent use. The record does not report intervention adherence or resource uptake. The conclusions that can be drawn from this record are therefore about the question and design, not about whether one approach improved health or whether any specific service was beneficial.

13. Why This Trial Matters Statistically

Statistically, this study brings together an intervention aimed at navigation and support with an outcome centered on diabetes-related distress. That pairing makes the estimand important: a comparison of assigned approaches on distress is different from a comparison of resource use, self-care behavior or any specific health service. The registry lists all of these kinds of outcomes, so clarity about which comparison is primary is essential.

The DDS17 score is an average on a defined scale, with higher scores indicating worse distress. Describing that direction helps readers interpret any future or posted numerical estimate. But a scale description is not an effect estimate. The registry record does not report a single primary comparison or its precision, so it is not possible to assess the size of an observed difference from the record information described.

The trial also illustrates why a label such as randomized or double-masked is not a substitute for reporting analysis details. Randomization describes assignment, while masking describes an intended feature of study conduct. To evaluate the result, readers also need to know who was masked, how outcomes were analyzed, how missing observations were handled and how multiple outcomes were addressed. These details are not reported in the registry record.

With 13 outcome measures and 34 analyses listed, the distinction between a principal result and a broader set of findings is especially relevant. Prespecification and multiplicity handling help readers understand how strongly to treat individual comparisons. Without that information, isolated secondary results, if encountered in other reporting, would require care in interpretation.

Finally, the planning assumptions based on the observed effect are illustrations, not evidence of what the trial was originally powered to detect. Keeping planning calculations separate from observed results prevents a common interpretive error. The registry’s design, endpoint and analysis gaps make this an example of why complete reporting of estimates, uncertainty and analytic decisions is necessary for a transparent statistical reading.

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.

Several limitations specific to this trial’s registry information affect interpretation. The primary outcome is identified as DDS17 change at baseline, Month 3 and Month 6, but the registry notes that the outcome spans several categories or time points and is not reduced to one comparison. The numerical primary result, its uncertainty and its analysis contrast are not reported in the registry record. The direction and magnitude of the primary finding therefore cannot be assessed.

The intervention and comparator are described at a broad level. The intervention is peer coaching, and the comparator is a directory with encouragement to follow up with a primary care physician. Details on coaching frequency, duration, fidelity, participant engagement and actual resource use are not reported in the registry record. Consequently, the degree of separation between the approaches in practice cannot be characterized.

The record identifies a double-masked design but does not specify who was masked or how masking was maintained. It does not report additional participant characteristics, recruitment settings or detailed eligibility criteria, which limits assessment of the population to which findings might apply. The primary outcome population is described as the full sample, but the number with available measurements at each assessment is not stated.

Analysis details are also absent: the primary statistical model, analysis population, missing-data approach, multiplicity plan and sensitivity analyses are not reported in the registry record. These omissions prevent evaluation of whether estimates account for repeated measurements and whether conclusions depend on analytic assumptions. The record’s adverse-event summaries do not provide event timing, causal attribution or a statistical safety comparison.

These are limitations of what is reported in the registry record. They should not be taken as proof that the study did not collect or analyze the relevant information. They do mean that the registry description alone does not support a detailed assessment of the primary result or its robustness.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Veteran Support and Resources for Diabetes — NCT04041375.
• Registry record last updated 2024-11-07; status last verified 2024-10.
• Results first posted 2024-07-05.
• 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.

18. Record Summary

NCT04041375, titled Veteran Support and Resources for Diabetes, is a completed randomized, double-masked, parallel-group study sponsored by the VA Office of Research and Development. Enrollment is reported as 219. The recorded study start date is 2019-10-01, and the primary completion date is 2022-08-09.

The study compares iNSPiRED peer coaching with Usual Care, described as a directory of resources and encouragement to follow up with a primary care physician. The primary outcome is change in DDS17 score at baseline, Month 3 and Month 6; higher scores indicate worse diabetes-related distress. The registry also lists secondary outcomes covering diabetes self-care, smoking, depressive symptoms, anxiety symptoms and use of community resources.

A single numerical primary comparison and its uncertainty are not reported in the registry record. The record also does not report the analysis population, missing-data methods, multiplicity handling or a detailed statistical plan. Serious adverse-event counts and deaths are reported by arm, but causal attribution and event timing are not stated.