Measurement of Cardiometabolic Risk in Antipsychotic-Treated Children: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Measurement of Cardiometabolic Risk in Antipsychotic-Treated Children (NCT00894738), a registered phase not stated study. The primary outcome is Carotid Artery Intima-media Thickness Measured by Ultrasonography..

2. Clinical Question

3. Trial Design

The registry describes a completed preliminary study of direct measures of cardiometabolic risk in children treated with antipsychotics. Washington University School of Medicine is listed as the sponsor. The study start date is 2010-01-01, the primary completion date is 2016-03-31, and the status is COMPLETED. Enrollment is listed as 44.

The two described groups were children with psychiatric diagnoses currently treated with antipsychotic medications and healthy controls. The controls are described as age- and gender-matched, without psychiatric diagnoses, not taking antipsychotic medications, and otherwise healthy. Allocation is not stated. The registry explicitly cautions that the arms are not a like-for-like control comparison, so differences between groups cannot automatically be attributed to antipsychotic treatment.

The listed intervention is a set of procedures: MRS, ultrasonography, DEXA, and blood tests. The study’s stated aims include beginning to establish the reliability and validity of hepatic triglyceride content and carotid intima-media thickness as biomarkers; describing their distribution across DEXA-measured adiposity; and examining their ability to predict risk as assessed by laboratory tests, including fasting lipids, liver function tests, C-reactive protein, and serum fibrinogen.

The registry lists two outcome measures and two analyses, but does not report detailed analysis methods, group allocation counts, eligibility criteria, or the timing of procedures beyond the primary outcome’s Week 1 timeframe. Randomization is not reported in the registry record. The registered primary endpoint is mean carotid artery intima-media thickness measured by ultrasonography.

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

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 Carotid Artery Intima-media Thickness Measured by Ultrasonography., measured over Week 1.

The primary endpoint is mean carotid artery intima-media thickness measured by ultrasonography, with millimeters as the unit, at Week 1. Intima-media thickness refers to the measured thickness of layers in the carotid artery wall. It is used in research as a structural marker relevant to vascular health and can be studied alongside other cardiometabolic indicators.

The registry’s broader rationale is to investigate whether direct measures such as carotid intima-media thickness and hepatic triglyceride content can serve as biomarkers of cardiometabolic risk in children treated for mental illness. It also describes assessing whether these measures predict risk indicated by laboratory tests. The primary endpoint is specifically carotid intima-media thickness; the registry does not give a corresponding numerical result, group mean, standard deviation, or estimate of association.

The registered summary statistic is a mean with standard deviation. The mean describes the group’s average measurement, while the standard deviation describes how spread out individual measurements are around that average. Those summaries can help characterize the measure in each group, but do not by themselves establish that a biomarker is reliable, valid, or predictive. Such conclusions require appropriate analyses and sufficient information about measurement procedures, uncertainty, and relevant sources of bias. Those details and the endpoint results are not reported in the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a mean and standard deviation describe?

The primary endpoint is continuous: it is a measurement in millimeters rather than a category or event count. A mean gives the average measurement in a group. A standard deviation describes how widely individual measurements vary around that mean. Reporting both can convey a group’s typical level and the spread of observations, but they do not show the full shape of the data. Skewness, outliers, or clusters can be hidden by these summaries.

For a group comparison, a difference between means is often an intuitive summary. Its interpretation depends on how participants entered each group, the completeness and quality of measurements, and whether important differences between groups are addressed. The registry does not report the primary endpoint’s group means or standard deviations, nor does it describe a model used to compare groups. A numerical contrast or its uncertainty therefore cannot be evaluated from the record.

What would an uncertainty interval add?

In general, a confidence interval expresses the range of effect estimates compatible with the data and the assumptions of the analysis. A narrow interval indicates greater precision than a wide interval, while an interval that includes values on different sides of no difference may leave the direction or size of an effect uncertain. An interval does not repair bias, establish causality, or prove that a biomarker is clinically useful. The registry does not report a confidence interval for the primary outcome.

A p-value, when reported, describes how unusual the observed data would be under a specified null model and its assumptions. It is not the probability that the null hypothesis is true, nor is it a measure of effect size or practical importance. The registry record does not report a p-value for carotid intima-media thickness. Without effect estimates and uncertainty, statistical significance cannot be assessed from the posted record.

Why does the group structure matter?

This study compares children receiving antipsychotic medications with healthy controls. The registry does not state that allocation was randomized and explicitly cautions that the arms are not a like-for-like control comparison. In general, an observational group contrast can reflect differences in participant characteristics, clinical circumstances, or other factors associated with group membership. Statistical adjustment can sometimes address measured differences, but it cannot guarantee removal of unmeasured confounding. The registry does not report whether adjustment was performed or which variables would have been included.

Age- and gender-matching is described for the healthy controls, but matching alone does not ensure comparability on other relevant characteristics. A suitable analysis may need to account for the matching structure, if applicable, as well as other design features. The registry does not provide enough detail to determine how matching was implemented or incorporated into analysis. It would be inappropriate to infer a particular model from the brief description.

What is the role of the biomarker analyses?

The stated scientific purpose is preliminary: to begin evaluating reliability and validity of hepatic triglyceride content and carotid intima-media thickness as biomarkers. Reliability concerns whether a measure is sufficiently consistent when it is repeated under appropriate conditions. Validity concerns whether a measure captures or relates to the construct it is intended to represent. Predictive assessment asks whether a measure can help anticipate an outcome or risk indicator. These are related but distinct questions; a measure can be associated with another indicator without being reliable or useful for prediction.

The registry describes examining biomarkers across a range of DEXA-measured adiposity and assessing prediction of risk indicated by fasting lipids, liver function tests, C-reactive protein, and serum fibrinogen. It does not report the analyses, estimates, validation approach, or predictive performance. The record therefore cannot establish whether these aims were met. No particular correlation, regression, discrimination measure, or validation procedure should be assumed.

How should planning illustrations be read?

Planning illustrations based on an observed effect are hypothetical calculations for future study design, not observed power and not evidence that the effect is real or reproducible. The registry’s stated assumptions are a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation, with planning directed at a stated proportion of the observed effect. Such illustrations depend on the estimate used as their starting point and on the assumptions chosen. They do not substitute for a prespecified sample-size justification for this study. The registry does not report the trial’s own sample-size justification.

In general, a planning calculation for participants per arm for 80% power estimates the group size under its assumptions for detecting a specified effect at a specified significance level. It is not a statement of the probability that the completed study found a real effect. The record does not report a protocol-based sample-size calculation, and planning illustrations should not be mistaken for an observed result.

Why can over-dispersion matter?

For continuous measurements, variability affects the precision of group summaries and comparisons. If a statistical model assumes less variability than the data actually contain, its uncertainty estimates may be too small and its inferential results too optimistic. More generally, over-dispersion means the observed variation is greater than a model’s assumed variation. This concept is especially familiar in count-data models, but the broader lesson is that uncertainty estimates should reflect the actual data structure. The registry does not report an assessment of dispersion or the model details needed to evaluate this issue.

The registry lists two analyses, but does not identify their methods or link them to particular outcomes. There is no basis in the record for claiming that a particular statistical test, adjustment, or diagnostic was used. Interpretation should remain limited to the design and endpoint descriptions that are actually reported.

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("Antipsychotic-Treated", "Healthy Control")
n   <- c(24, 19)
m   <- c(0.508, 0.519)
sp  <- c(0.053, 0.048)
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  Antipsychotic-Treated  24  0.508  0.053  0.486  0.530
CARM  Healthy Control  19  0.519  0.048  0.496  0.542

11. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and two analyses, but does not report the full analysis plan, identify all planned hypotheses, or state whether any adjustment for multiple testing was used. When several outcomes or comparisons are examined, the chance of at least one apparently unusual result can increase. In general, multiplicity procedures can control that risk, but their appropriateness depends on which hypotheses are considered part of the same family and on the scientific goals. The record does not provide enough detail to determine whether multiplicity was a concern or how it was handled.

Missing-data methods and outcome-specific denominators are not reported in the registry record. The enrollment figure does not show how many participants contributed a primary endpoint measurement or whether data were incomplete. In general, analyses based only on complete observations can be biased if missingness is related to participant characteristics or outcomes. Other approaches make assumptions about the missing-data process and should be described and justified. No specific approach can be attributed to this study from the registry information.

Analysis populations are also not reported. The record does not state whether all enrolled participants, participants with available measurements, or another defined population were included in each analysis. Since allocation is not stated and the comparison is not described as randomized, it would also be inappropriate to assume an intention-to-treat population. Without analysis-population definitions, missing-data handling, and denominators, the representativeness and precision of reported estimates cannot be assessed. The primary endpoint results themselves are not reported in the registry record.

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

The registry record describes a preliminary investigation of direct cardiometabolic risk measures in children treated with antipsychotics, with healthy controls as a comparator. It establishes that carotid artery intima-media thickness was the primary endpoint, measured by ultrasonography in millimeters at Week 1, and that the endpoint was to be summarized as a mean with standard deviation. It also describes broader aims involving hepatic triglyceride content, DEXA-measured adiposity, and laboratory indicators of cardiometabolic risk.

The record does not report the numerical primary outcome or the findings of the broader biomarker assessments. It therefore cannot establish the size or direction of a group contrast, the precision of an estimate, or whether either biomarker predicts the listed laboratory indicators. Absence of those results in the registry record is not evidence that the groups were identical, that an association was absent, or that an analysis failed.

Even if group results were available, an observational comparison of antipsychotic-treated children and healthy controls would not by itself isolate the effect of medication. The registry does not state that allocation was randomized and cautions that the groups are not a like-for-like control comparison. Group differences could be associated with other differences between the populations. The posted information does not report adjustment methods that might help address measured differences.

The registry lists no serious events, other events, or deaths in either group. Those entries describe the adverse-event counts recorded there; they do not establish the absence of all harms or answer whether the biomarkers are valid. The study’s preliminary purpose is relevant to measurement and research design, but its posted record does not support a clinical conclusion about treatment or an individual child’s risk.

13. Why This Trial Matters Statistically

This study is statistically notable because it focuses on the measurement properties and potential predictive value of biomarkers, rather than presenting itself as a randomized test of antipsychotic treatment. For research in children, direct measures such as hepatic triglyceride content and carotid intima-media thickness may be studied alongside established laboratory indicators to understand whether they capture useful aspects of cardiometabolic risk. The registry frames this as an early step toward evaluating reliability and validity, not as a definitive validation.

The design also illustrates why a control group’s description matters. Age- and gender-matched healthy controls can provide a reference for understanding measurements, but the registry warns that the comparison is not like-for-like and does not report random allocation. A difference between groups would need cautious interpretation because it might reflect group characteristics beyond medication exposure. This is a central distinction between describing an association and identifying a causal effect.

The listed outcomes and stated aims raise separate statistical questions: how measurements are distributed across adiposity, how well they relate to laboratory indicators, and whether they are reliable and valid as biomarkers. Each requires suitable methods and uncertainty estimates. The registry’s brief record does not provide those results, making transparency about what is and is not reported important for readers who may otherwise mistake a study rationale for evidence of validation.

Finally, the planning illustrations are not observed power and should not be read as confirmation of a finding. Their value is prospective: under stated assumptions, they can inform planning for future studies. The distinction between exploratory estimation and confirmatory evidence is especially important in a preliminary biomarker study.

14. Limitations

• The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
• Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.

The principal limitation for interpreting the posted record is that it does not report the primary endpoint results. Group means, standard deviations, outcome-specific denominators, uncertainty intervals, and hypothesis-test results are not reported. Without these, the direction, magnitude, and precision of any observed contrast cannot be assessed.

The registry identifies the study as preliminary, while its broader aims involve reliability, validity, and prediction. It does not report the methods or results needed to judge those properties. In particular, the record does not describe repeat measurements or a reliability analysis, a validation strategy, or performance measures for prediction. The stated aims should not be mistaken for findings.

The comparison is limited by the group structure described in the record. Antipsychotic-treated children with psychiatric diagnoses are contrasted with healthy children without psychiatric diagnoses who are not taking antipsychotics. Allocation is not stated, and the registry cautions that the arms are not a like-for-like control comparison. The record does not report covariate adjustment or other methods for addressing differences between groups.

Important reporting details are absent, including eligibility criteria, group allocation counts, missing-data procedures, analysis populations, and the statistical methods used for the two listed analyses. The registry also does not report the trial’s own sample-size justification. These omissions prevent a detailed assessment of selection, precision, and analytic choices. The listed zero adverse-event counts should likewise be interpreted as registry entries, not as a comprehensive safety assessment.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Measurement of Cardiometabolic Risk in Antipsychotic-Treated Children — NCT00894738.
• Registry record last updated 2026-08-20; status last verified 2026-08.
• Results first posted 2019-06-06.
• 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

NCT00894738 is a completed preliminary study sponsored by Washington University School of Medicine, with enrollment listed as 44. The registry lists Mental Disorders as the condition and procedures including MRS, ultrasonography, DEXA, and blood tests. The study aimed to examine cardiometabolic biomarkers in children treated with antipsychotics in comparison with healthy controls.

The primary endpoint was mean carotid artery intima-media thickness measured by ultrasonography in millimeters at Week 1. The record describes broader aims concerning hepatic triglyceride content, adiposity, and laboratory indicators, but does not report the numerical results. Allocation is not stated, and the registry cautions that the groups are not a like-for-like control comparison. It lists zero serious events, zero other events, and zero deaths in each group.