The Role Of Omega-3 Fatty Acids In Adolescent Depression: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for The Role Of Omega-3 Fatty Acids In Adolescent Depression (NCT00962598), a randomized phase 2 study. The primary outcome is ACC Glx/Water.

2. Clinical Question

The study addresses a biological measurement in adolescents with MDD. Its stated purpose is not framed as a test of symptom improvement, remission, or another clinical outcome. Although the condition and treatment are clinically relevant, the posted primary outcome concerns the ratio of Glutamine-Glutamate and water in the brain.

The treatment was compared with corn oil in a randomized, parallel-group design. The registry describes quadruple masking, but does not report which roles were masked. The primary outcome timeframe is baseline and 10-weeks. Because the outcome has several categories or time points and has not been reduced to a single comparison in the registry record, the direction and size of a primary treatment contrast cannot be read from the record.

3. Trial Design

This was a phase 2, randomized, quadruple-masked, parallel-group study sponsored by Icahn School of Medicine at Mount Sinai. The registry lists enrollment of 16 and a completed status. The recorded start was 2006-01, and primary completion was 2013-06. These registry dates describe the study record; they do not supply outcome results or explain the timing of recruitment and follow-up.

The listed interventions were omega-3 fatty acids and corn oil. For omega-3 fatty acids, the initial dose was 1.2g/d. The dose was to increase gradually by 0.6 per 2 weeks, up to a possible maximum daily dose of 3.6 g/d. The corn oil dosage was to correspond to the experimental treatment's titration schedule. The record therefore describes an active comparator designed to follow the same dosing schedule, rather than a comparison with no assigned intervention.

The stated treatment phase lasted 10 weeks. The primary outcome timeframe is baseline and 10-weeks. The record describes the measurement as the ACC Glx/Water ratio and says it reflects the ratio of Glutamine-Glutamate and water in the brain, with the ratio divided by 10000 for analysis purposes. Proton magnetic resonance imaging is identified as the measurement approach in the study summary.

The registry record does not report the allocation sequence method, concealment procedures, the specific roles included in quadruple masking, or adherence and treatment-discontinuation details. It also does not report a sample-size justification, a detailed protocol, or a statistical analysis plan. These omissions do not establish what procedures were or were not used; they mean those details are not reported in the registry record.

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 ACC Glx/Water, measured over baseline and 10-weeks.

The primary endpoint is titled ACC Glx/Water. It is a continuous measure reported as a mean with standard deviation, with units given as ratio * 10^-4. The registry describes it as the ratio of Glutamine-Glutamate and water in the brain, and notes that the ratio was divided by 10000 for analysis purposes. The stated timeframe is baseline and 10-weeks.

In general, a continuous endpoint represents a measured quantity that can take a range of values, rather than a count of events or a yes-or-no outcome. Reporting a mean describes the central value in a group, while a standard deviation describes the spread of measurements around that mean. Neither summary alone establishes whether groups differ; an estimated contrast and its uncertainty are needed to assess the evidence for a difference.

The study summary identifies proton magnetic resonance imaging as the method used to examine brain chemistry. The registry’s description connects Glutamate with Glutamine and identifies Glutamate as a precursor to Glutamine and an excitatory neurotransmitter. That biological context explains what the measure is intended to represent; it does not establish that a change in the ratio corresponds to a particular change in depressive symptoms or clinical status.

The registry record does not provide numerical baseline or 10-weeks values, a between-group estimate, or an uncertainty interval for ACC Glx/Water. It also does not report a detailed definition of the analysis population for this endpoint. The measure can therefore be described from the record, but its observed treatment comparison cannot be interpreted.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does a continuous endpoint mean?

ACC Glx/Water is recorded as a continuous endpoint. In general, continuous measurements can vary along a scale, so a study can describe them with means and measures of spread. The registry identifies the mean as the parameter and standard deviation as the dispersion measure. A mean can summarize the typical level in a group, while the standard deviation indicates how variable participant measurements are around that group mean. A group mean is not a description of every participant’s measurement.

A treatment comparison would normally make the contrast between groups explicit. For a measure recorded at baseline and follow-up, possible summaries can answer different questions: the follow-up group means, changes within each group, or a direct between-group contrast in change. These are not automatically equivalent. The registry record does not report which numerical contrast was analyzed, and it does not provide estimates for any of these possibilities. No particular model or adjustment should be inferred from the outcome label alone.

How should uncertainty be read?

In general, a confidence interval gives a range of values compatible with the observed data and the method used to calculate the interval. Its width conveys precision: a wider interval indicates less precision than a narrower interval, all else equal. The interval is especially useful alongside an estimated effect because it shows both the direction and the range of plausible magnitudes under the analysis. No confidence interval or treatment estimate for ACC Glx/Water is reported in the registry record.

A p-value, in general, describes how unusual data at least as discrepant as those observed would be under a specified null hypothesis and statistical model. It is not the probability that the null hypothesis is true, nor does it establish that an effect is important. A p-value cannot substitute for an estimate and its interval. The registry record does not report a primary outcome p-value.

What does the masking and allocation information tell readers?

Randomized allocation means the trial record identifies assignment as randomized, and parallel design means participants were assigned to study arms followed in parallel. These design features can support a fair comparison when implemented and analyzed appropriately. The registry records quadruple masking, but does not identify which study roles were masked or explain the procedures used. Thus, the masking label alone does not tell readers whether participants, care providers, outcome assessors, or analysts were among the masked roles.

Randomization does not remove all uncertainty, particularly in a study with enrollment listed as 16. The amount of information available for an outcome also depends on how many measurements were obtained and analyzed and how variable they were. The registry record does not report outcome-specific group counts, variability, or missing measurements. No precision assessment can be reconstructed from the enrollment figure alone.

Why can over-dispersion matter?

In general, over-dispersion means that observed variability is greater than a statistical model expects. When that occurs, a model that assumes less variability can produce uncertainty estimates that are too small and evidence that appears more precise than warranted. Model choice should reflect the outcome’s distribution and the way the data were collected. ACC Glx/Water is described as a continuous measure with a mean and standard deviation, but the registry record does not report a fitted model, a variance assessment, or any finding about over-dispersion. This general consideration should not be read as evidence that over-dispersion occurred in this study.

How should the planning assumptions be understood?

The record describes sample-size planning illustrations using a two-sided significance level of 0.05, equal allocation between arms, and a normal approximation. The target effect is expressed as a stated fraction of the observed effect. In general, such calculations ask how many participants per arm would be needed under chosen assumptions to detect a target effect at a chosen significance level. They are prospective planning illustrations, not a measure of the study’s observed power and not a substitute for its actual outcome estimate and uncertainty.

The observed effect used by a planning illustration can itself be uncertain, particularly when estimated from a study with limited information. A planning calculation based on an observed effect should therefore not be treated as proof that a future study will reproduce that effect. The registry record does not report the trial’s own sample-size justification, and it does not provide the outcome estimate needed to independently assess the illustration assumptions. No planning value should be interpreted as a result from the randomized comparison.

What analysis details are absent?

The registry records 0 analyses and does not report the analysis model, an adjustment strategy, the handling of missing outcome measurements, or an analysis population for the primary endpoint. It also does not report whether an interim analysis was planned or conducted. These details affect how an estimate should be interpreted, but their absence from the registry record does not prove that no such methods were used outside the record.

The outcome is not reduced to one comparison because it has several categories or time points. General statistical practice requires clarity about the outcome contrast being tested, especially when multiple choices could be considered. Without that definition and without posted results, there is no basis for reconstructing a primary test, checking its assumptions, or judging the precision of an estimate. The sponsor’s own analysis would take precedence over a simple unadjusted recalculation if the record identified a discrepancy; no recalculated outcome comparison is available in the registry record.

10. Multiplicity, Missing Data and Analysis Populations

The registry record notes that the primary outcome has several categories or time points and is not reduced to one comparison. When a study considers multiple measurements or comparisons, multiplicity can matter: the chance of at least one apparently notable result can increase as more tests are considered. In general, a prespecified analysis plan can identify the primary contrast and explain whether and how multiple testing is addressed. The registry record does not report a multiplicity strategy or identify a single numerical primary contrast.

The record lists 2 outcome measures and 0 analyses. It does not report which outcome measures were analyzed, whether all planned measurements were collected, or how the endpoint categories or time points relate to the planned primary comparison. Without this information and without outcome estimates, there is no basis for assessing selective reporting or interpreting a result across multiple tests.

Missing-data methods and analysis populations are also not reported in the registry record. In general, missing measurements can affect both the estimated effect and its precision; the consequences depend on why measurements are missing and how the analysis handles them. A complete-case analysis, an imputation method, and a model using available measurements rely on different assumptions. None should be attributed to this study without documentation.

The record does not state whether the primary outcome analysis was intended to follow randomized assignment, include only participants with measurements, or use another population definition. These omissions limit reproducibility and make it difficult to connect the registered design to any estimated treatment effect. They do not establish that missing data or multiplicity problems occurred; they identify information not reported in the registry record.

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 reports serious adverse event figures separately for Corn Oil and Omega-3 Fatty Acids. For Corn Oil, 0 serious adverse events were recorded among 7 at risk; for Omega-3 Fatty Acids, 0 were recorded among 9 at risk. The record also reports 0 other adverse events among 7 at risk in the Corn Oil group and 0 among 9 at risk in the Omega-3 Fatty Acids group. Deaths are recorded as 0 in both groups.

These figures describe the adverse-event counts in the registry record. They do not establish that no adverse events could occur, and they do not give a precise estimate of the frequency of uncommon events. A zero count in a group does not mean that the underlying risk is zero. The number at risk, the way events were collected, the observation period for safety, and the definitions used all affect interpretation.

The registry does not list serious adverse event terms, and the timeframe for these safety counts is not reported in the registry record. The figures should therefore be read as a limited account of recorded events, not as a complete characterization of safety or a comparison with enough detail to estimate relative risk. These safety counts are separate from the primary brain chemistry outcome and do not provide evidence about its results.

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

The registry documents a randomized, parallel-group phase 2 study of omega-3 fatty acids and corn oil in adolescents with major depressive disorder. Its stated purpose was to examine effects on brain chemistry during a 10-week treatment phase. The primary measure, ACC Glx/Water, is described as a ratio involving Glutamine-Glutamate and water in the brain, assessed at baseline and 10-weeks.

That information establishes what comparison the study was designed to investigate, not what the comparison found. The registry record does not report group outcome values, a treatment-effect estimate, a confidence interval, or a p-value. It therefore cannot show whether the measure changed, whether groups differed, or how precisely any difference was estimated. Missing results must not be interpreted as no effect, equal outcomes, or evidence favoring either intervention.

The endpoint is a brain chemistry measure, not a reported clinical symptom endpoint. Even if a numerical change in ACC Glx/Water were available, its interpretation would depend on the size and precision of the change, the analysis definition, and the relationship between the measure and outcomes relevant to participants. The registry record does not report evidence that would establish such a relationship for this trial. The biological description of Glutamate and Glutamine supplies context for the measure, but is not a clinical result.

The safety figures report no serious or other adverse events in the listed groups and no deaths. Those counts are limited to what the registry records and do not determine the overall safety profile. The record also omits safety timeframe details and serious-event terms.

In general, randomized designs can support causal comparisons when allocation, follow-up, measurement, and analysis are appropriately conducted. The registry’s design labels alone cannot demonstrate that all relevant assumptions were met. With no posted primary outcome analysis and limited analysis details, the defensible conclusion is that the record describes the research question and design but does not provide the results needed to answer that question.

13. Why This Trial Matters Statistically

This trial is statistically notable as a randomized study of a biological endpoint rather than a reported symptom outcome. The primary measure is a continuous brain chemistry ratio, with a baseline and 10-weeks timeframe. That makes the definition of the analyzed contrast important: a group mean at follow-up, a within-group change, and a between-group difference in change would convey different information.

The registry records enrollment of 16 and identifies a phase 2 study. In general, the amount of information in a study affects the precision of estimated effects. With limited enrollment, estimates can be uncertain, but the actual precision cannot be judged from enrollment alone; outcome variability and analyzed group counts are also needed. Those endpoint details are not reported in the registry record.

The record also illustrates why a registered outcome is not equivalent to a posted result. It identifies the measure and timeframe but does not provide numerical outcome summaries, an analysis, or a multiplicity approach. Because the outcome has several categories or time points, knowing the specific contrast and how choices among measurements were handled would be especially important for interpreting any reported estimate.

Finally, the sample-size assumptions described in the record are planning concepts, not evidence about what the trial observed. A planning illustration is conditional on its assumptions and does not replace an effect estimate with an uncertainty interval. The distinction between design information, planned analysis, observed data, and inferential results is central to reading this record responsibly.

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 primary limitation for interpreting efficacy is that the registry record does not report numerical results for ACC Glx/Water. There are no group means, standard deviations, treatment estimates, confidence intervals, or p-values in the posted information. The record’s completed status does not supply those missing results, and the absence of a reported comparison cannot be taken as evidence of no difference.

The registered primary endpoint has several categories or time points and is not reduced to a single comparison. The record does not clarify the intended contrast, identify a primary analysis time point beyond the listed baseline and 10-weeks timeframe, or describe how multiple measurements were handled. It also does not report missing-data procedures, the analysis population, an analysis model, or outcome-specific group counts.

Enrollment is listed as 16, but that figure alone does not reveal how many participants contributed measurements at each time point or how much information the endpoint contains. The registry does not report the standard deviations or other outcome distributions needed to judge precision. Nor does it report the trial’s own sample-size justification.

The study summary describes a 10-week omega-3 fatty acid treatment phase and a brain chemistry aim. The record does not provide enough detail to assess adherence, treatment discontinuation, imaging measurement procedures, or the specific roles covered by quadruple masking. Further, the ACC Glx/Water measure is not a reported symptom outcome, and the record does not establish how this biological measure relates to clinical changes.

Safety interpretation is also limited by the absence of serious adverse event terms and a reported safety timeframe. These gaps should be treated as limits of the registry record, not proof that procedures, results, or monitoring were absent from the study itself.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: The Role Of Omega-3 Fatty Acids In Adolescent Depression — NCT00962598.
• Registry record last updated 2018-04-24; status last verified 2018-04.
• Results first posted 2017-05-24.
• 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

The registry record describes NCT00962598, The Role Of Omega-3 Fatty Acids In Adolescent Depression, as a completed phase 2 randomized, quadruple-masked, parallel-group study sponsored by Icahn School of Medicine at Mount Sinai. Enrollment is listed as 16; the recorded start was 2006-01 and primary completion was 2013-06.

The comparison was omega-3 fatty acids versus corn oil in adolescents with major depressive disorder. The omega-3 regimen began at 1.2g/d and increased gradually by 0.6 per 2 weeks to a possible maximum daily dose of 3.6 g/d. The primary measure was ACC Glx/Water, a brain chemistry ratio assessed at baseline and 10-weeks.

The registry record does not report numerical primary outcome results or analyses. Its safety entries list 0 serious adverse events and 0 other adverse events in both groups, with 0 deaths. The outcome comparison, analysis details, missing-data approach, and multiplicity strategy are not reported in the registry record.