Cardiovascular Risk Stratification in Young People With Type 1 Diabetes: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Cardiovascular Risk Stratification in Young People With Type 1 Diabetes (NCT05283538), a na na study. The primary outcome is Change of Statin Prescription Indication Between Consensus of the French Society of Cardiology and the French Speaking Society of Diabetology 2020 and the ESC/EASD Consensus.

2. Clinical Question

The underlying clinical question is whether assessment of coronary calcium would classify cardiovascular risk differently from recommendations based on clinical guidance, with potential consequences for whether a statin is indicated. The registry summary describes concern that recommendations may assign risk categories using diabetes duration, while CAC could provide an additional measure of coronary calcification. That rationale motivates the comparison, but it is not itself evidence that one approach identifies risk more accurately.

The primary outcome is framed as a count of people whose statin indication would change, rather than as a cardiovascular event, a change in CAC, or a treatment effect. The registry record therefore asks about reclassification of a prescribing indication. It does not report the number reclassified, the direction of any changes, or the extent to which the two approaches agreed.

3. Trial Design

The registry describes a completed, single-group study sponsored by Poitiers University Hospital, with 91 participants enrolled. The listed intervention is coronary artery calcification evaluation, categorized as a diagnostic test. The record gives no randomized allocation and no masking. This is therefore not a randomized comparison of two participant groups or a blinded treatment trial.

The study’s central comparison is made between risk-stratification approaches: the 2019 ESC/EASD recommendations and CAC-based assessment. These approaches are the conceptual comparators for the primary question, not separate trial arms. The listed arm is “Coronary Artery Calcification Evaluation”; its description is blank in the registry record. The record identifies one outcome measure and a timeframe of 1 day for the primary endpoint.

The registry lists the study start as 2022-03-28 and primary completion as 2025-03-28, and its status is completed. The record gives the condition as type 1 diabetes and coronary artery calcification. Phase is listed as not applicable. The registry does not report a detailed protocol, eligibility criteria beyond the age range in the primary outcome description, or the procedures used to obtain and interpret CAC scores.

Because there is no like-for-like control group, any difference in prescribing indications should be understood as a comparison of classification rules applied in the study context, not as a causal estimate of what would happen under alternative treatments. The registry record does not report a statistical analysis plan, the intended sample-size justification, or additional analysis details. It also does not provide the primary outcome result, so the size and pattern of any reclassification cannot be assessed from the posted results.

4. Participant Flow and Accounting

The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.

Overall Study

Analysis population for the primary outcome, as defined in the registry: 2 patients with a missing target LDL and 4 patients with a missing CAC score

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.

Population: Patients with available primary outcome measures.

6. Primary Endpoint

The registry lists the primary outcome as Change of Statin Prescription Indication Between Consensus of the French Society of Cardiology and the French Speaking Society of Diabetology 2020 and the ESC/EASD Consensus, measured over 1 day.

The primary endpoint is the count of participants for whom the indication to prescribe a statin for primary prevention would change when CAC is used as a cardiovascular risk assessment tool instead of the 2019 ESC/EASD guidelines. It is recorded in participants, and the listed timeframe is 1 day. The endpoint description applies to people with type 1 diabetes aged 18 to 35.

This endpoint measures a change in prescribing classification, not a change in cardiovascular health, a change in cholesterol, or a clinical benefit from taking a statin. It is used to quantify how often the two risk-stratification approaches would lead to different indications. In principle, reporting the count could describe how much the choice of assessment method affects treatment eligibility in the studied population.

The registry record describes the comparison but does not report the observed count. It also does not report how many changes would be toward or away from a statin indication, the total number of participants with each indication under either approach, or an uncertainty interval around the count. The population note states that 2 patients had a missing target LDL and 4 had a missing CAC score; it does not explain how those missing values were handled in calculating the endpoint. Consequently, the endpoint’s definition is available, but its result and analytic details are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The study’s endpoint is a count: the number of participants for whom a statin indication for primary prevention would change under CAC-based assessment compared with the 2019 ESC/EASD guidelines. A count is a natural descriptive measure for a question about how many people are classified differently. The registry labels the endpoint as a count of participants and gives a timeframe of 1 day. It does not report the count itself or an inferential analysis of it.

What a count can describe

In general, a count reports the number of observed people meeting a defined condition. To interpret it fully, readers usually need the denominator and the rules used to decide whether each person meets that condition. Here, the record lists 91 enrolled participants, but does not state the denominator used for the primary outcome analysis. It notes 2 patients with a missing target LDL and 4 with a missing CAC score, without explaining whether they were included or excluded from the endpoint calculation. The outcome result and its analysis population are not reported in the registry record.

A count of changed indications would also need to be interpreted alongside the pattern of changes. A single overall count would not, by itself, show how many participants changed from no indication to an indication, how many changed in the opposite direction, or how many had the same classification under both approaches. Those details are not reported in the registry record.

Uncertainty and confidence intervals

General statistical explanation: a confidence interval describes uncertainty around an estimated quantity under the assumptions of the analysis. For a reclassification count or a proportion, an interval can help readers judge whether the estimate is precise or compatible with a wider range of values. A point estimate without an uncertainty measure gives less information about how stable the result may be beyond the observed participants. The registry record does not report an interval or other measure of uncertainty for the primary endpoint, and no recalculated estimate can be made from the posted results because the endpoint count is absent.

General statistical explanation: statistical significance and clinical or decision relevance are different questions. A test can address whether data are inconsistent with a specified null model, while the size and direction of a reclassification describe its practical meaning. This registry record does not report a primary endpoint analysis, a p-value, or a null hypothesis. It is therefore not possible to assess statistical evidence against a particular hypothesis from the posted results.

Why the design matters

The registry lists a single group and a diagnostic test, with no randomized allocation or masking. The two approaches being compared are guideline-based classification and CAC-based classification, rather than assigned interventions in parallel arms. General statistical explanation: a paired or within-person comparison can be useful when two methods are applied to the same individuals, because it focuses on disagreement within individuals rather than differences between separate groups. The record does not give enough analysis detail to confirm how the two approaches were applied or how within-person comparisons were summarized.

This design can describe classification changes in the study sample, but it cannot by itself establish that using one approach causes better health outcomes. Nor does a change in indication establish that the revised classification is more accurate. Evaluating accuracy would generally require an appropriate reference standard or follow-up outcome; the registry record does not report such an analysis.

Missing data and model assumptions

The primary outcome population note identifies missing target LDL data for 2 patients and missing CAC scores for 4 patients. General statistical explanation: missingness can affect a comparison when a participant cannot be classified by one or both methods. Complete-case analysis, imputation, and other approaches can lead to different estimates, depending on the missingness pattern and assumptions. The registry record does not report the method used, the overlap between the missing-data groups, or whether missingness was considered in the analysis.

The registry’s separate planning-illustration assumptions specify a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the detectable effect expressed as a stated fraction of the observed effect. Those assumptions describe a planning illustration, not the study’s reported design: the registry describes a single-group study, not an equal-allocation, two-arm randomized comparison. The planning values and the trial’s own sample-size justification are not reported in the registry record. Such illustrations are not observed power and cannot replace an analysis of the actual endpoint.

General statistical explanation: over-dispersion matters when count data vary more than a chosen statistical model expects; if ignored, uncertainty can be understated. Whether over-dispersion is relevant depends on the outcome structure and model. No count model, dispersion assessment, or inferential analysis is reported in the registry record, so there is no basis to say that over-dispersion was present or how it was handled.

10. Exact Estimates for Each Arm

No two-arm comparison is shown for this trial, but each arm's result can still be summarized with exact interval estimates computed from the posted counts. The Clopper-Pearson interval is exact and conservative; the Wilson interval is a common closer-to-nominal alternative; the Bayesian credible interval uses a uniform Beta(1, 1) prior. For small groups the three can differ noticeably.

R code and output

arm    <- c("Change of Statin Prescription Indication Between C")
n      <- c(85)
events <- c(32)
for (i in seq_along(n)) {
  ci <- binom.test(events[i], n[i])$conf.int          # Clopper-Pearson exact interval
  cr <- qbeta(c(0.025, 0.975), 1 + events[i], 1 + n[i] - events[i])   # Bayesian, uniform Beta(1,1) prior
  wi <- (function(x, n) { p <- x / n; z <- qnorm(0.975); d <- 1 + z^2 / n
    c((p + z^2 / (2 * n) - z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d, (p + z^2 / (2 * n) + z * sqrt(p * (1 - p) / n + z^2 / (4 * n^2))) / d) })(events[i], n[i])
  cat(sprintf("ARM|%s|%d|%d|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f|%.1f\n", arm[i], n[i], events[i], 100 * events[i] / n[i],
              100 * ci[1], 100 * ci[2], 100 * wi[1], 100 * wi[2], 100 * cr[1], 100 * cr[2]))
}

ARM  Change of Statin Prescription Indication Between C  85  32  37.6  27.4  48.8  28.1  48.3  28.1  48.3

11. Multiplicity, Missing Data and Analysis Populations

The registry lists one primary outcome measure. It does not report a multiplicity adjustment, a hierarchy of hypotheses, or whether additional outcomes were assessed outside the registry entry. The number of listed outcome measures does not establish whether the study had other planned analyses. Any approach to multiplicity is not reported in the registry record.

Missing information is explicitly noted for the primary endpoint population: 2 patients had a missing target LDL and 4 patients had a missing CAC score. The record does not state whether these are distinct participants or overlapping groups. It also does not say whether the missing values prevented classification, whether participants were excluded from the endpoint analysis, or whether values were imputed or otherwise addressed. The number included in the primary analysis is not reported in the registry record.

The registry gives 91 as the enrollment count, but enrollment is not necessarily the same as the number contributing to a particular endpoint. No analysis population definition is reported, such as an intention-to-treat or evaluable-participant population. Because the study is a single-group diagnostic assessment, the record also does not describe a treatment-arm analysis population.

These omissions limit interpretation of any potential reclassification result, particularly because the endpoint depends on information used by the competing approaches. The primary outcome count itself is not reported, and there is no stated missing-data strategy or analysis population with which to interpret it. The registry record also does not report interim analyses or a statistical analysis plan. No assumptions about those procedures can be made from the posted record.

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.

The adverse-event figures list 91 participants at risk for serious events and 0 participants affected by serious events in the “Coronary Artery Calcification Evaluation” group. The figures also list 91 at risk for other events and 0 affected by other events, with 0 deaths. These are the registry’s posted counts for the group.

These counts describe what is recorded in the registry; they do not establish that no event of any kind occurred outside the definitions or reporting period used for the entry. The registry record does not provide event terms, a more detailed observation period, or information about how adverse events were collected. The listed primary outcome timeframe is 1 day, but the record does not specify the adverse-event observation timeframe.

The safety counts should be read separately from the primary endpoint, which concerns a change in statin-prescribing indication. The posted adverse-event figures do not provide evidence about the accuracy of CAC-based risk classification or about treatment effects. They are descriptive registry counts, and the record does not provide further detail to interpret them beyond the listed numbers.

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

The study asks whether CAC-based cardiovascular risk assessment would alter statin-prescribing indications compared with the 2019 ESC/EASD recommendations among young people with type 1 diabetes. The registry identifies 91 enrolled participants and describes the primary outcome as a count of participants whose indication would change. However, the registry record does not report that count. As a result, the main quantitative question remains unanswered in the posted results.

The record does not show whether CAC assessment led to more or fewer statin indications, how many participants had unchanged indications, or how well either approach classified cardiovascular risk. It also does not report cardiovascular events or outcomes after treatment. The study’s stated rationale—that CAC might refine risk stratification—is a motivation for examining the question, not a result demonstrating that it does so.

Even a reported change in prescribing indication would have a specific interpretation: it would measure a difference in classification under two approaches. It would not, on its own, show that one approach is more accurate, that the changed indication is appropriate, or that treatment decisions based on it improve health. Those claims would require evidence and analyses not reported in this registry entry.

The record also lacks the primary outcome’s uncertainty estimate, the analysis population, and the method used to handle missing target LDL and CAC information. These gaps prevent assessment of the precision and robustness of a reclassification estimate. The safety counts list 0 serious events, 0 other events, and 0 deaths among 91 participants at risk in the CAC evaluation group, but the registry provides limited detail about event ascertainment.

Overall, the registry record documents a completed single-group diagnostic assessment and its intended comparison. It does not report enough outcome information to quantify reclassification or draw a statistical conclusion about the performance of either risk-stratification approach.

14. Why This Trial Matters Statistically

This study addresses a statistical distinction between risk classification and clinical outcomes. Its primary question is whether applying CAC assessment rather than the 2019 ESC/EASD recommendations would change statin indications. That is a question about agreement and reclassification: it asks whether two approaches lead to the same label for each participant, or different labels. Such questions are important because a change in classification is not automatically a change in underlying risk or evidence of improved prediction.

The single-group design makes clear why the comparison must be described carefully. The registry does not compare randomized treatment groups. Instead, it frames guideline recommendations and CAC-based assessment as alternative approaches for determining indications. A difference between those approaches would be descriptive of how they classify the participants studied; it would not establish a causal treatment effect.

Missing information is also central to statistical interpretation. The record notes missing target LDL data for 2 patients and missing CAC scores for 4 patients, but does not report how those data were handled. When different approaches depend on different measurements, missing values can affect who can be classified by both methods and, therefore, the apparent degree of reclassification. Without the analysis population and missing-data method, precision and potential bias cannot be evaluated.

The registry’s primary result is not reported, so the size of the classification difference cannot be assessed. That absence matters: the design and rationale alone do not establish whether reclassification occurred or how common it was. The record is useful for identifying the question and the limits of the available evidence, but quantitative interpretation requires the outcome count and its analysis details.

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 most direct limitation of the registry entry is that it does not report the primary endpoint result. Although the endpoint is defined as a count of participants whose statin indication would change, the count, its direction, and any uncertainty measure are absent. The primary question therefore cannot be quantified from the posted results.

The analysis population is also not reported. The registry notes 2 patients with missing target LDL and 4 with missing CAC scores, but does not state whether those groups overlap or how missing information affected eligibility for the endpoint analysis. No method for handling missing values is described. This is particularly relevant because the endpoint compares classifications that rely on the information available for each approach.

The study is listed as a single-group diagnostic assessment with no randomized allocation or masking. Its comparison is between risk-stratification approaches, not treatment arms. The record does not report whether a reference standard or follow-up cardiovascular outcome was used to evaluate classification accuracy. Therefore, the design description alone cannot establish which approach better predicts future events or improves decisions.

The registry provides limited detail about the study procedures. It does not report a full protocol, detailed eligibility criteria, CAC interpretation procedures, or a statistical analysis plan. It also does not report interim analyses or a sample-size justification. The planning-illustration assumptions listed in the record are not the study’s own design and do not provide the missing justification or observed endpoint analysis. Safety figures are reported as counts, but event terms and the adverse-event observation period are not detailed.

These are limitations of what the registry record reports; they should not be taken as evidence that unreported procedures were or were not conducted.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Cardiovascular Risk Stratification in Young People With Type 1 Diabetes — NCT05283538.
• Registry record last updated 2026-10-22; status last verified 2026-06.
• Results first posted 2026-10-22.
• 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

NCT05283538 is a completed, single-group study sponsored by Poitiers University Hospital, with 91 participants enrolled. The listed intervention is coronary artery calcification evaluation, categorized as a diagnostic test. The study concerns type 1 diabetes and coronary artery calcification.

The primary endpoint is the count of participants whose statin indication for primary prevention would change using CAC instead of the 2019 ESC/EASD recommendations. Its listed timeframe is 1 day, and its description specifies patients with type 1 diabetes aged 18 to 35. The registry record does not report the primary endpoint count or an analysis of it. The population note identifies missing target LDL data for 2 patients and missing CAC scores for 4 patients, without reporting how these were handled.

The adverse-event listing records 0 serious events, 0 other events, and 0 deaths among 91 participants at risk. The record does not describe the event observation period in detail. Statistical analysis methods, the analysis population, and the sample-size justification are not reported in the registry record.