This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record. Numerical trial results on this page are restricted to the results posted in the ClinicalTrials.gov record; calculations added by Clinical Biostats are labelled as such.
1. Trial at a Glance
This page covers the registry results for Fish Oil for HIV-Related Inflamm-aging and Immune Senescence (NCT02102724), a randomized na study. The primary outcome is Change in Markers of Immune Senescence Between Baseline Values and Values After 12 Weeks of Supplementation.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02102724 |
| Phase | NA |
| Condition | HIV Infection |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 37 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Rush University Medical Center |
| Results posted | Yes |
2. Clinical Question
Population
Older adults with HIV infection. The registry record lists HIV infection as the condition and describes participants as HIV-infected older adults. Enrollment is listed as 37.
Intervention
Fish oil gelcaps containing 1.6 grams of omega-3 fatty acids for 12 weeks: 800 mg of EPA, 600 mg DHA, and 200 mg other omega-3 fatty acids.
Comparator
Placebo consisting of 1 gram of oleic sunflower oil for 12 weeks.
Primary question
How do changes in specified CD4+ and CD8+ T-lymphocyte senescence markers compare between the fish-oil and placebo groups from baseline to the end of the 12-week supplementation period?
The trial’s rationale is that HIV infection is associated with premature immune aging, and persistent inflammation is proposed as a contributor. Fish oil is described in the registry record as having anti-inflammatory properties. The study therefore tests whether a 12-week course of supplementation is associated with changes in cellular markers of immune senescence. That rationale does not itself establish that the intervention changes the markers.
The outcome description identifies percentages of peripheral CD4+ and CD8+ T lymphocytes expressing the CD28-/CD57- or CD28-/CD57+ marker combinations. For each marker, the stated change score is the baseline percentage minus the percentage at Week 12. The planned comparison is between the groups’ change scores. The registry record does not report numerical estimates for these comparisons, so it does not establish the direction, size, or precision of any difference.
3. Trial Design
This was a randomized, double-masked, parallel-group clinical trial sponsored by Rush University Medical Center. Its status is listed as completed. The recorded start is 2014-04, and primary completion is listed as 2015-12. The registry lists the phase as NA. Enrollment is listed as 37.
Participants were assigned to fish oil or placebo. The fish-oil arm received gelcaps containing omega-3 fatty acids for 12 weeks, while the placebo arm received oleic sunflower oil for 12 weeks. The record describes masking as double but does not identify which roles or individuals were masked. Details such as the randomization sequence, allocation concealment, and how masking was maintained are not reported in the registry record.
The primary outcome is a continuous measure expressed as a percentage of cells. It concerns changes from baseline to the end of the 12-week supplementation period in CD28 and CD57 markers on peripheral CD4+ and CD8+ T lymphocytes. The record specifies Wilcoxon rank sum tests for intergroup change scores. It also lists a mean as the outcome parameter and a 95% confidence interval as the dispersion measure, but numerical estimates are not reported in the registry record.
Safety information lists the groups separately, with 18 participants at risk for the reported serious and other adverse-event summaries in the fish-oil group and 19 in the placebo group. Those figures describe the safety summaries; they should not be treated as confirmation that all randomized participants completed treatment or had complete primary-outcome measurements. Completion, adherence, withdrawals, and the analysis population are not reported in the registry record.
The registry record does not describe the sample-size justification, an interim-analysis plan, or a detailed statistical analysis plan. The study’s completed status and its recorded design features do not fill in those missing methodological details.
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
| Stage | Fish Oil | Placebo |
|---|---|---|
| STARTED | 18 | 19 |
| COMPLETED | 16 | 18 |
| NOT COMPLETED | 2 | 1 |
Reasons for not completing this period:
| Reason | Fish Oil | Placebo |
|---|---|---|
| Lost to Follow-up | 1 | 0 |
| surgery for brain aneurysm | 1 | 1 |
Analysis population for the primary outcome, as defined in the registry: Wilcoxon rank sum tests for intergroup change scores
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.
| Characteristic | Unit | Fish Oil | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 18 | 19 | 37 | |
| Age, Continuous | years | 55 (SD 5.4) | 53 (SD 6.1) | 54 (SD 5.8) |
| Sex: Female, Male: Female | Participants | 9 | 9 | 18 |
| Sex: Female, Male: Male | Participants | 9 | 10 | 19 |
| Region of Enrollment: United States | participants | 18 | 19 | 37 |
6. Primary Endpoint
The registry lists the primary outcome as Change in Markers of Immune Senescence Between Baseline Values and Values After 12 Weeks of Supplementation, measured over End of 12-Week Supplementation Period.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | percentage of cells |
| Endpoint classification | Continuous Endpoint |
The primary endpoint concerns change in the percentage of peripheral CD4+ and CD8+ T lymphocytes expressing specified senescence-marker combinations. The markers are CD28 and CD57, and the combinations listed are CD28-/CD57- and CD28-/CD57+. Measurements are described at baseline and after 12 weeks of supplementation. For each marker, the stated change score is calculated by subtracting the Week 12 percentage from the baseline percentage.
These cell-surface markers are used in the trial to characterize immune senescence. The study’s rationale connects HIV-related persistent inflammation with premature aging of the immune system and asks whether supplementation is associated with changes in these cellular measures. This is a biological-marker question; the registry record does not describe a clinical event or symptom endpoint.
Because the change is baseline minus Week 12, a positive value would indicate a lower Week 12 percentage than at baseline, while a negative value would indicate a higher Week 12 percentage. That direction describes the arithmetic only; it does not, by itself, establish whether a change is clinically meaningful or beneficial. The endpoint spans CD4+ and CD8+ cells and more than one marker combination. Numerical results for the individual categories are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies the trial as completed and describes its primary outcome and planned group comparison. It does not report the numerical results needed to interpret the primary endpoint: there are no group-level change estimates, between-group effect estimates, confidence-interval limits, or test results in the record. Consequently, the direction and magnitude of the observed marker changes, and the precision of any group contrast, are not reported in the registry record.
The endpoint is a change score, defined as baseline percentage minus Week 12 percentage. Its sign would indicate the direction of change in the measured cell percentage, but would not alone establish the importance of that change. Interpretation would also depend on the actual estimates, their uncertainty, how the several marker categories relate to one another, and the clinical context. Those numerical and contextual details are not reported in the registry record.
The record names a Wilcoxon rank sum test for intergroup change scores. That identifies a comparison method, not the result of the comparison. No p-value or other inferential result is reported in the registry record. A named test cannot establish whether the data favored one group, whether a difference was compatible with chance variation, or how large a difference may have been.
The trial’s enrollment is listed as 37, and the safety summaries list 18 participants at risk in the fish-oil group and 19 in the placebo group. These registry entries do not show how many participants contributed complete primary-outcome data, whether all randomized participants were analyzed, or how missing measurements were handled. Those details are not reported in the registry record, limiting assessment of potential bias and the reliability of the primary comparison.
Accordingly, the available record supports describing the research question, trial design, endpoint, and named test. It does not support a conclusion about whether fish oil changed the measured immune-senescence markers relative to placebo. A completed trial is not, by itself, evidence of a particular outcome. The posted data must include numerical outcome estimates and their uncertainty before the treatment contrast can be assessed.
9. Statistical Methods Explained
The registry record names a Wilcoxon rank sum test for comparing intergroup change scores. The following explanation is general: a rank sum test converts observed values into ranks and assesses whether values from one independent group tend to be higher or lower than values from another. It can be useful when a comparison should not rely on a normal-distribution model for the raw measurements. It does not, without additional assumptions, test only a difference in group means.
What does the rank sum test compare?
In this trial, the values to be compared are described as change scores, rather than only the Week 12 measurements. Each score is calculated from a participant’s baseline and Week 12 percentages. The test then compares the distributions of those changes between the fish-oil and placebo groups. General statistical interpretation requires care: if the distributions have different shapes or spreads, a rank-based result should not automatically be described as a difference in medians. The record does not report distributional plots, test statistics, or numerical results, so the pattern of the observed data cannot be assessed.
The endpoint is expressed as a percentage of cells, while the analysis uses within-participant change scores and a between-group test. A change score addresses how each participant’s measure shifts over the measurement period; the group comparison asks whether those shifts differ between assigned groups. This is distinct from testing whether one group changed from its own baseline. A within-group change alone would not establish a difference between treatments.
How should the confidence interval be understood?
The record identifies the mean as the outcome parameter and a 95% confidence interval as the dispersion measure. General explanation: a confidence interval communicates the precision of an estimate under the method used to construct it. A narrower interval indicates greater precision than a wider interval, while an interval that includes values on both sides of a reference value may leave substantial uncertainty about direction. A confidence interval is not a guarantee that the true value lies within its limits, nor does it by itself establish clinical importance.
The numerical means and confidence-interval limits are not reported in the registry record. The interval’s construction method is also not reported. The named rank sum test and the listed mean with confidence interval describe different statistical summaries; the record does not explain how these were combined or which summary was intended for the between-group contrast. It is therefore not possible to reconstruct or interpret a particular estimate.
Why do distributions and over-dispersion matter?
General statistical explanation: a statistical method’s assumptions affect what its output means. When measurements are highly skewed, contain influential observations, or have unequal distributions between groups, a simple mean-based model may not represent the data well. Rank-based methods can reduce reliance on a particular parametric distribution, but they do not remove every assumption or make the analysis immune to outliers, ties, missing observations, or measurement problems. Over-dispersion, in general, means that observed variability exceeds what a model assumes; if present and ignored in a model that depends on a variance assumption, uncertainty may be understated. The registry record does not report whether over-dispersion was assessed or relevant to this analysis.
The change-score definition also matters. Subtracting Week 12 from baseline gives a value whose sign runs opposite to a Week 12-minus-baseline convention. The method is explicitly stated, so the direction of a reported change would need to be read using that convention. No direction or value is available in the registry record.
What can be inferred from a test result?
General explanation: a p-value, if reported, describes how compatible the observed data are with a specified null model under the test’s assumptions. It is not the probability that the null hypothesis is true, and it does not measure the size or clinical relevance of an effect. Estimation and uncertainty are therefore important alongside a test result. In this record, no p-value, test statistic, or numerical effect estimate is reported, so there is no inferential result to interpret.
The record also states planning assumptions for a sample-size illustration: a two-sided significance level of 0.05, equal allocation, a normal approximation, and detection of a stated fraction of an observed effect. These are planning assumptions, not evidence that the trial was designed with those assumptions and not a measure of observed power. The record does not report the trial’s own sample-size justification. No planning participant counts are reported in the registry record. Any planning illustration should be understood as conditional on its assumptions, rather than as a trial result or proof that the study could detect a particular effect.
Finally, the endpoint includes several marker categories and cell types. A separate test for each could raise multiplicity concerns, because making several comparisons can increase the chance of at least one apparently unusual result. The registry record does not explain whether each category was tested separately, how results were selected for reporting, or whether multiplicity was addressed. Without that information and the numerical outcomes, neither the strength nor the scope of statistical evidence can be evaluated.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists one outcome measure and one analysis, while the primary outcome description includes CD4+ and CD8+ T lymphocytes and the CD28-/CD57- and CD28-/CD57+ marker combinations. It also specifies measurements at baseline and after 12 weeks. Thus, the single listed outcome measure encompasses multiple categories of measurement. The record does not report a single numerical comparison that combines those categories, and numerical results for the categories are not reported in the registry record.
Multiplicity arises when multiple hypotheses or outcome categories are tested. General statistical explanation: the more comparisons made, the greater the chance of observing at least one result that appears unusual under a null model. Methods such as prespecifying a primary contrast, adjusting inference, or interpreting estimates as exploratory can address different aspects of this issue. Which approach was used in this trial is not reported in the registry record. A multiplicity adjustment should not be assumed from the number of listed analyses.
Missing-data procedures are not reported in the registry record. The record does not describe the amount or pattern of missing primary-outcome measurements, whether participants who discontinued were included, or whether values were imputed. It also does not state whether the primary analysis followed an intention-to-treat principle, used a per-protocol population, or applied another analysis-population definition.
These omissions matter because missing measurements can affect both the estimated change and the group comparison, particularly if missingness differs between groups or is related to participants’ outcomes. The available enrollment and safety denominators do not resolve how many participants contributed to each primary comparison. The handling of missing data, the analysis population, and any multiplicity strategy are not reported in the registry record.
11. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Fish Oil | 1 | 18 | 5.6% |
| Placebo | 1 | 19 | 5.3% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Fish Oil | 0 of 18 |
| Placebo | 0 of 19 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Fish Oil | 8 of 18 |
| Placebo | 4 of 19 |
Most frequent serious adverse event terms
| Event term | Organ system | Fish Oil | Placebo |
|---|---|---|---|
| lymphoma | Blood and lymphatic system disorders | 0 of 18 | 1 of 19 |
| brain aneurysm | Nervous system disorders | 1 of 18 | 0 of 19 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Fish Oil | Placebo |
|---|---|---|---|
| GI disturbance | Gastrointestinal disorders | 8 of 18 | 4 of 19 |
Serious events with the highest arm-level rate: brain aneurysm (5.6%), lymphoma (5.3%).
The safety summaries list the fish-oil group with 18 participants at risk and one participant affected by a serious adverse event; the placebo group lists 19 at risk and one affected by a serious adverse event. Deaths are listed as 0 in both groups. For other adverse events, the registry lists 8 affected in the fish-oil group and 4 in the placebo group. These are descriptive counts, not a statistical comparison of risk.
The registry also lists “brain aneurysm” with 5.6% and “lymphoma” with 5.3% among the top serious terms. The record does not identify those terms with a particular treatment group in the information. They should not be interpreted as rates for a specific arm or as evidence of a causal relationship to supplementation.
Adverse-event counts do not establish that treatment caused an event. The record does not report event timing, severity beyond the serious-event classification, relatedness assessments, recurrent events, or how events were collected. The numbers also do not describe the primary immune-marker outcome. Small descriptive counts can be unstable and do not, on their own, establish that one group had a higher underlying risk.
12. What the Result Does, and Does Not, Mean
The registry record supports a clear description of the study question: whether changes in specified immune-senescence markers differed between fish oil and placebo over 12 weeks in older adults with HIV infection. It also identifies a randomized, double-masked, parallel design and a Wilcoxon rank sum test for intergroup change scores. Those design and methods details describe how the question was framed; they do not reveal the answer.
The numerical primary-outcome estimates and inferential results are not reported in the registry record. Therefore, the direction and magnitude of any between-group difference, its precision, and its compatibility with chance variation cannot be determined from this record. No conclusion that fish oil improved, worsened, or had no effect on the measured markers is supported by the information.
The endpoint is a cellular marker measure, not a direct measure of clinical outcomes. Even if numerical changes were available, their clinical meaning would depend on the size and precision of the between-group contrast and on how those marker changes relate to health outcomes. The registry record does not report that relationship or a threshold for interpreting a meaningful change.
Likewise, the adverse-event counts are descriptive and do not establish causation or comparative safety. The record does not provide enough detail to determine whether reported events were judged related to study supplementation. Absence of a reported death in the safety summaries is not a substitute for a complete assessment of other harms.
The most defensible reading is therefore limited: the trial was completed, its registered question and endpoint are identifiable, and a group-comparison method is named, but the primary numerical result is not reported in the registry record. A treatment conclusion would require outcome estimates, uncertainty, and enough information about missing data and analysis choices to judge how the comparison was conducted.
13. Why This Trial Matters Statistically
This trial illustrates how a biological rationale becomes a statistical question. The rationale links HIV infection, persistent inflammation, and premature immune aging; the endpoint translates that question into measured percentages of specified cell types and marker combinations. The trial then defines change from baseline to Week 12 and compares those changes between randomized groups. Keeping these steps distinct helps prevent the proposed mechanism from being mistaken for an observed result.
It also highlights the difference between an outcome concept and an analyzable contrast. The primary outcome is described as one measure, but it includes CD4+ and CD8+ cells and multiple marker combinations. A reader needs to know which contrasts were estimated, how each was reported, and whether multiplicity was considered. Those details are not reported in the registry record, and numerical outcome results are not reported either.
The record names a rank-based test while listing means and 95% confidence intervals as the outcome summary. This makes clear why statistical reporting should connect the estimand, test, and uncertainty measure. A test alone does not communicate the size or precision of a treatment contrast, and a mean alone does not explain how the distribution was compared.
Finally, a completed trial can still have an incomplete results record for interpreting its main question. Design details and safety summaries are useful, but they cannot replace primary-outcome estimates, missing-data information, and analysis-population definitions. The distinction between what was planned, what was measured, and what was reported is central to sound interpretation of clinical evidence.
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 most direct limitation for interpretation is that numerical primary-outcome results are not reported in the registry record. There are no group-specific change estimates or between-group estimates, confidence-interval limits, or test results. This prevents assessment of the direction, magnitude, and precision of the principal comparison.
The primary endpoint includes several cell types and marker combinations. The record does not report category-specific findings or explain whether the categories were analyzed as separate comparisons, combined in a prespecified way, or treated as exploratory. A multiplicity strategy is not reported. This makes it difficult to know how an overall conclusion would relate to the several measurements named in the outcome description.
Several details needed to assess conduct and analysis are also not reported in the registry record: the randomization procedure, allocation concealment, the roles covered by double masking, adherence, withdrawals, missing primary measurements, and the analysis population. The record names a Wilcoxon rank sum test and lists means with 95% confidence intervals, but does not report how the confidence intervals were constructed or how the summary and test were connected.
The enrollment is listed as 37, while the safety summaries give group-specific at-risk counts. Those safety figures do not establish the number contributing to the primary analysis or the completeness of follow-up. The trial’s own sample-size justification and any interim-analysis plan are not reported in the registry record. The planning assumptions described for an illustration should not be treated as the trial’s design justification or as observed power.
Finally, the endpoint is a set of immune-cell markers. The registry record does not establish how changes in these markers correspond to clinical outcomes. Safety reporting is also limited to counts and listed serious-event terms, without event attribution or additional detail about timing and severity.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Fish Oil for HIV-Related Inflamm-aging and Immune Senescence — NCT02102724.
- Registry record last updated 2019-03-26; status last verified 2019-03.
- Results first posted 2019-03-26.
- 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.
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Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
NCT02102724 is a completed randomized, double-masked, parallel trial sponsored by Rush University Medical Center. It lists enrollment of 37 and examines fish oil versus oleic sunflower oil placebo for 12 weeks in older adults with HIV infection.
The primary outcome concerns baseline-to-Week 12 changes in CD28 and CD57 marker combinations on peripheral CD4+ and CD8+ T lymphocytes. The stated analysis compares intergroup change scores using Wilcoxon rank sum tests. The record lists a mean and 95% confidence interval as the outcome summary, but numerical primary results are not reported in the registry record.
The safety summaries list one serious adverse event in each group and no deaths in either group. Other affected-event counts and serious-event terms are also listed, but the record does not establish causation. Details about missing data, analysis populations, multiplicity, and the trial’s sample-size justification are not reported in the registry record.