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 Treatment for Non-Alcoholic Fatty Liver With Different Doses of Vitamin E (NCT01792115), a randomized phase 2 study. The primary outcome is Biochemical: Number of Patients With Normal Transaminases at End of Treatment..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01792115 |
| Phase | Phase 2 |
| Condition | Fatty Liver |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 22 |
| Arms in the primary outcome | 3 |
| Lead sponsor | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) |
| Results posted | Yes |
2. Clinical Question
Population
Adults at least 18 years of age with a suggestion of non-alcoholic fatty liver disease (NAFLD). The registry describes fatty liver as the condition of interest; it does not give further detail about the analyzed population for the primary outcome.
Intervention
Daily vitamin E at 200 IU, 400 IU, or 800 IU for 24 weeks. The registry also describes an optional open-label extension using 800 IU/day for up to 120 weeks after the initial treatment period.
Comparator
The posted randomized arms are the three vitamin E doses. The intervention list includes diet and exercise, but the registry record does not describe a separate randomized diet-and-exercise arm among the posted primary-outcome results.
Primary question
At the end of treatment, how many participants in each dose arm had normal transaminases, defined as AST <=32 or ALT <=35 U/L? The registry presents counts for each arm but does not report a statistical comparison among doses.
The trial addresses whether different doses of vitamin E are associated with different biochemical response counts among participants with fatty liver. The registry background notes uncertainty about whether a lower dose could have an effect similar to the higher dose used in earlier studies, and describes an interest in understanding how vitamin E may work at different doses.
The primary outcome is a count meeting a threshold-based definition at 24 weeks, rather than a continuous change in enzyme concentration. The record also lists secondary outcomes for absolute and percent changes in AST and ALT, absolute change in GGT, and percent change in liver fat. Those measures could describe biochemical or liver-fat changes in different ways, but their numerical results are not reported in the posted results.
The record does not report an untreated or placebo comparison for the primary outcome. Consequently, the reported arm counts address response counts across the three dose groups, not whether vitamin E differs from no vitamin E or from diet and exercise alone.
3. Trial Design
This is a randomized, phase 2, parallel-group trial with no masking. The registry lists total enrollment as 22 and status as completed. The posted primary-outcome results are organized by three randomized vitamin E dose arms: 200 IU/day, 400 IU/day, and 800 IU/day. Each arm description specifies 24 weeks of assigned treatment.
The registry gives a study start date of 2013-05-01 and a primary completion date of 2019-08-30. It also describes an optional open-label extension: participants in each dose group were invited to receive 800 IU/day for up to 120 weeks after the initial 24-week period. The primary outcome is specified at the end of treatment, at 24 weeks; the record does not provide results for the extension in the posted primary-outcome figures.
The study is unmasked, so participants and study personnel were not blinded to assigned treatment according to the registry description. Random allocation can help balance baseline characteristics on average, but the record does not report the sequence-generation method, allocation concealment procedures, or how randomization was implemented. These details are not reported in the registry record.
The brief summary describes screening with an examination, medical history, and blood and urine collection. It also says participants would meet with a nutritionist during the first 12 weeks and receive personalized diet and exercise guidance; the summary text is incomplete. Although diet and exercise appear in the intervention list, a separate diet-and-exercise randomized arm is not represented in the posted primary-outcome arm results. The role of those activities in relation to all randomized groups is therefore not fully specified by the registry record.
The primary endpoint results report 6 participants with normal transaminases in the 200 IU/day arm, 6 in the 400 IU/day arm, and 6 in the 800 IU/day arm. The corresponding endpoint denominators are 7, 6, and 8 participants. The safety listings use a denominator of 7 for both the 200 IU/day and 400 IU/day groups and 8 for the 800 IU/day group; those denominators should not be assumed to be the same analysis population as the primary endpoint.
The registry does not report the trial's sample-size justification, target power, or planned statistical analysis. It also does not explain the difference between the enrollment figure and the participants represented in the endpoint groups. No assumptions about these design details can be made from the posted 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
| Stage | Vit E 200 IU/d | Vitamin E 400 | Vitamin E 800 |
|---|---|---|---|
| STARTED | 7 | 7 | 8 |
| COMPLETED | 7 | 6 | 8 |
| NOT COMPLETED | 0 | 1 | 0 |
Reasons for not completing this period:
| Reason | Vit E 200 IU/d | Vitamin E 400 | Vitamin E 800 |
|---|---|---|---|
| Lost to Follow-up | 0 | 1 | 0 |
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 | Vit E 200 IU/d | Vitamin E 400 | Vitamin E 800 | Total |
|---|---|---|---|---|---|
| Participants analysed | 7 | 7 | 8 | 22 | |
| Age, Continuous | years | 52.3 (SD 14.6) | 43.9 (SD 9.3) | 48.4 (SD 11.3) | 48.2 (SD 11.8) |
| Sex: Female, Male: Female | Participants | 5 | 3 | 2 | 10 |
| Sex: Female, Male: Male | Participants | 2 | 4 | 6 | 12 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 5 | 4 | 5 | 14 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 2 | 3 | 3 | 8 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 1 | 1 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): White | Participants | 2 | 3 | 2 | 7 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 5 | 4 | 5 | 14 |
| Diabetes: Has Diabetes | Participants | 0 | 2 | 3 | 5 |
| Diabetes: No Diabetes | Participants | 7 | 5 | 5 | 17 |
6. Primary Endpoint
The registry lists the primary outcome as Biochemical: Number of Patients With Normal Transaminases at End of Treatment., measured over 24 weeks.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the number of participants with normal transaminases at the end of treatment, defined at 24 weeks. A participant meets the registry definition if AST is <=32 or ALT is <=35 U/L. The outcome is therefore a count of participants meeting a biochemical threshold, rather than the average enzyme value or the average change from baseline.
A threshold-based endpoint can be useful when the clinical or biological question concerns how many participants reach a specified range. It is also straightforward to describe as a count in each treatment group. However, a count alone does not show the magnitude of enzyme changes among participants who remain outside the threshold, nor does it distinguish a small change from a large change for those who cross it. The definition uses an “or” condition, so meeting either enzyme threshold qualifies.
The registry reports 6 participants meeting the definition in each of the three dose arms. The endpoint denominators are 7 for 200 IU/day, 6 for 400 IU/day, and 8 for 800 IU/day. The record does not report baseline enzyme status, individual participant values, the handling of missing measurements, or an adjusted estimate comparing dose groups. It also does not provide a confidence interval or a hypothesis test for this endpoint.
The registry lists secondary outcomes including absolute and percent change in AST, absolute and percent change in ALT, absolute change in GGT, and percent change in liver fat. These outcomes may offer complementary descriptions of changes, but their numerical results are not reported in the posted results described in the record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary outcome is descriptive. At 24 weeks, the count meeting the normal-transaminase definition is 6 in each listed vitamin E dose arm. The endpoint denominators are 7 for the 200 IU/day arm, 6 for the 400 IU/day arm, and 8 for the 800 IU/day arm. Because the denominators differ, equal counts do not by themselves imply equal response proportions. No proportions need to be inferred to read the posted result: the registry gives counts, not a dose-group effect estimate.
The record does not provide a confidence interval, p-value, or other measure of uncertainty for the primary outcome. It therefore does not quantify how compatible the observed counts are with a range of possible differences among dose groups. With small arm counts, an individual participant's classification can have a noticeable influence on the displayed count. This is a general feature of small samples, not evidence that any particular participant's result was misclassified.
No adjusted or unadjusted comparison among dose arms is posted. The registry also does not give baseline characteristics or baseline transaminase values alongside the primary result. Without those details, it is not possible to assess balance in prognostic factors or to understand how many participants may already have met the threshold before treatment. Randomization is an important design feature, but it does not replace reporting the analysis and its uncertainty.
The completed status and enrollment entry provide trial-level context, but they do not resolve which participants contributed to each endpoint. The enrollment figure is 22, while the endpoint groups are reported with denominators of 7, 6, and 8. The safety listings use a different denominator for the 400 IU/day group. Reasons for these differences, including whether they reflect missing endpoint measurements or different analysis populations, are not reported in the registry record.
The registry's primary outcome is a threshold classification at one specified time point. It does not directly summarize the trajectory of AST or ALT over time, the magnitude of change, or the listed liver-fat outcome. Although the record lists several secondary measures, their numerical findings are not available in the posted results summarized by the registry entry.
In general, a randomized comparison is most informative when the assigned groups, analysis population, outcome definition, and uncertainty around treatment contrasts are all reported. Here, the randomization and endpoint counts are recorded, but the comparative estimates and statistical tests are not. The counts can be described as observed results; they do not establish that one dose differs from another or that any dose caused the outcome.
9. Statistical Methods Explained
The registry describes a randomized, parallel-group, unmasked phase 2 study. In a parallel design, participants are assigned to a group and receive that group's intervention during the comparison period. Randomization is intended, in general, to reduce systematic differences between groups at the point of assignment. It does not ensure that groups will be identical, especially in a small trial, and the record does not report baseline characteristics that would allow readers to examine observed balance.
What does the endpoint count?
The primary outcome is binary at the participant level: each participant either meets the normal-transaminase definition at 24 weeks or does not. The registry defines the qualifying result as AST <=32 or ALT <=35 U/L. The posted arm values are counts of participants meeting that definition. They are not means, changes from baseline, or estimates of the difference between treatments.
For binary outcomes, a group count is commonly interpreted alongside the number of participants assessed. The registry reports the counts and denominators by arm, but it does not provide a comparative estimate or confidence interval. In general, an effect estimate would state the contrast being used, such as a difference in response proportions or a relative measure, and a confidence interval would describe the statistical uncertainty around that estimate. Neither is reported for this endpoint.
What does randomization tell us?
Random allocation supports a fair comparison by making assignment independent of participants' measured and unmeasured characteristics in expectation. That protection depends on the actual allocation process and can be weakened in practice by problems such as departures from assigned treatment, missing outcome measurements, or selective analysis. The registry says the study was randomized, but the sequence-generation process, allocation concealment, adherence, and participant flow are not reported in the registry record.
The trial was unmasked. In general, knowledge of treatment assignment can affect behavior, co-interventions, outcome assessment, or decisions about which measurements are available. The concern depends on the outcome and how it is assessed. AST and ALT are laboratory measures, but the registry does not describe laboratory procedures, centralized assessment, or safeguards for outcome measurement.
Why do confidence intervals matter?
In general, a confidence interval presents a range of values compatible with the data and the statistical model used. Its width reflects precision: a wide interval signals that the data do not pin down the effect closely. A point estimate alone can conceal substantial uncertainty. Since no confidence interval or treatment contrast is posted for the primary endpoint, the precision of differences among the vitamin E doses cannot be evaluated from the registry result.
A p-value, when reported, addresses how unusual data at least as extreme as the observed data would be under a specified null hypothesis and model. It is not the probability that a treatment effect is true, and it does not communicate the size or clinical importance of an effect. The registry does not report a p-value or a formal comparison for the primary outcome.
What can the sample-size illustration establish?
In general, planning calculations can illustrate how many participants per arm might be needed to detect a chosen effect under specified assumptions. The registry's planning description says its illustration uses the observed effect, a two-sided significance level of 0.05, equal allocation, and a normal approximation; the target effect is a stated fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence that the trial was designed with those assumptions. The trial's own sample-size justification is not reported in the registry record. Numerical planning results are not reported in the record details, so no required sample size can be stated.
In general, calculations based on an observed effect can be unstable when the observed estimate comes from a small study. A sample-size illustration should not be read as evidence that the study had adequate power, nor does a planning target substitute for a confidence interval or a completed analysis. The registry does not report the protocol assumptions that would be needed to characterize the original design calculation.
What is over-dispersion?
In general, over-dispersion describes variability greater than a statistical model assumes. It matters when a model's standard errors rely on an assumption that variation follows a particular distribution; underestimated variability can make intervals too narrow and tests too optimistic. The primary outcome is reported as counts in small groups, but the registry does not report a fitted model or dispersion assessment. No claim about over-dispersion or model adequacy can be made from these results.
The study also lists continuous secondary outcomes, including enzyme changes and liver-fat change. In general, continuous outcomes can be summarized using a location measure and a measure of spread, while binary outcomes are often summarized using counts and proportions. The registry's listed secondary outcomes do not come with numerical estimates or uncertainty measures in the posted results. The analysis methods for them are not reported in the registry record.
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.
| Arm | Participants | Events | Observed % | Clopper-Pearson 95% CI | Wilson 95% CI | Bayesian 95% credible interval |
|---|---|---|---|---|---|---|
| Vit E 200 IU/d | 7 | 6 | 85.7% | 42.1% to 99.6% | 48.7% to 97.4% | 47.3% to 96.8% |
| Vitamin E 400 | 6 | 6 | 100.0% | 54.1% to 100.0% | 61.0% to 100.0% | 59.0% to 99.6% |
| Vitamin E 800 | 8 | 6 | 75.0% | 34.9% to 96.8% | 40.9% to 92.9% | 40.0% to 92.5% |
R code and output
arm <- c("Vit E 200 IU/d", "Vitamin E 400", "Vitamin E 800")
n <- c(7, 6, 8)
events <- c(6, 6, 6)
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 Vit E 200 IU/d 7 6 85.7 42.1 99.6 48.7 97.4 47.3 96.8
ARM Vitamin E 400 6 6 100.0 54.1 100.0 61.0 100.0 59.0 99.6
ARM Vitamin E 800 8 6 75.0 34.9 96.8 40.9 92.9 40.0 92.511. Multiplicity, Missing Data and Analysis Populations
The registry lists multiple outcomes: the primary biochemical count and secondary measures of AST, ALT, GGT, and liver fat. Testing multiple outcomes or multiple dose contrasts can increase the chance of at least one apparently notable result arising by chance. In general, a prespecified analysis plan can clarify which comparisons are primary and whether any adjustment or hierarchical testing approach is intended. The registry record does not report a multiplicity strategy or a statistical analysis plan.
The primary outcome counts are posted by arm, but no comparative statistical analysis is reported. There are no posted p-values, confidence intervals, adjusted estimates, or unadjusted estimates for the primary outcome. The record also does not state whether all planned comparisons were conducted or how secondary outcomes were analyzed. The number of outcome measures is recorded as 8, and six secondary outcomes are listed; numerical secondary results are not reported in the registry entry.
The record does not describe missing-data handling, the number of participants with missing primary measurements, or the reasons for any missingness. It also does not identify whether the primary analysis included all randomized participants, participants who completed treatment, or another analysis population. In general, these choices matter because excluding participants with unavailable outcomes can affect comparability if missingness is related to treatment assignment or outcome status.
The endpoint denominators differ from the overall enrollment entry and from one safety denominator. These figures do not establish why participants are absent from a particular analysis. Without a participant-flow account and explicit analysis-population definitions, the extent and treatment of missing data cannot be assessed. The relevant details are not reported in the registry record.
12. 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 |
|---|---|---|---|
| Vit E 200 IU/d | 1 | 7 | 14.3% |
| Vitamin E 400 | 0 | 7 | 0.0% |
| Vitamin E 800 | 3 | 8 | 37.5% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Vit E 200 IU/d | 0 of 7 |
| Vitamin E 400 | 0 of 7 |
| Vitamin E 800 | 0 of 8 |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Vit E 200 IU/d | 7 of 7 |
| Vitamin E 400 | 7 of 7 |
| Vitamin E 800 | 8 of 8 |
Most frequent serious adverse event terms
| Event term | Organ system | Vit E 200 IU/d | Vitamin E 400 | Vitamin E 800 |
|---|---|---|---|---|
| Gastrointestinal Bleed | Gastrointestinal disorders | 0 of 7 | 0 of 7 | 1 of 8 |
| Diuretic-induced hypokalemia | Renal and urinary disorders | 0 of 7 | 0 of 7 | 1 of 8 |
| Diverticulitis with recto-vaginal fistula | Gastrointestinal disorders | 0 of 7 | 0 of 7 | 1 of 8 |
| Hypertensive crisis (medication non-compliance) | Cardiac disorders | 1 of 7 | 0 of 7 | 0 of 8 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Vit E 200 IU/d | Vitamin E 400 | Vitamin E 800 |
|---|---|---|---|---|
| Iron deficiency or anemia | Blood and lymphatic system disorders | 3 of 7 | 4 of 7 | 4 of 8 |
| Hypokalemia | Metabolism and nutrition disorders | 2 of 7 | 0 of 7 | 2 of 8 |
| Headache/Migraine | Nervous system disorders | 1 of 7 | 0 of 7 | 1 of 8 |
| Shoulder pain | Musculoskeletal and connective tissue disorders | 0 of 7 | 0 of 7 | 2 of 8 |
| Epistaxis | Vascular disorders | 0 of 7 | 0 of 7 | 2 of 8 |
| Overt gastrointestinal bleeding | Gastrointestinal disorders | 0 of 7 | 0 of 7 | 2 of 8 |
| Depression | Psychiatric disorders | 0 of 7 | 1 of 7 | 0 of 8 |
| Rash | Skin and subcutaneous tissue disorders | 1 of 7 | 0 of 7 | 0 of 8 |
| Viral gastroenteritis | Infections and infestations | 1 of 7 | 0 of 7 | 0 of 8 |
| Galactorrhea | Reproductive system and breast disorders | 1 of 7 | 0 of 7 | 0 of 8 |
Serious events with the highest arm-level rate: hypertensive crisis (medication non-compliance) (14.3%), gastrointestinal bleed (12.5%), diuretic-induced hypokalemia (12.5%), diverticulitis with recto-vaginal fistula (12.5%).
The serious adverse event listings report 1 affected participant among 7 at risk in the 200 IU/day group, 0 among 7 in the 400 IU/day group, and 3 among 8 in the 800 IU/day group. Deaths are recorded as 0 in each group. The separate “other” adverse-event listing reports 7 affected among 7 at risk in the 200 IU/day group, 7 among 7 in the 400 IU/day group, and 8 among 8 in the 800 IU/day group. These are counts from the registry safety listings, not comparative estimates.
The safety denominators do not match the primary-outcome denominator for the 400 IU/day group, which is 6. The registry does not explain the difference or provide details about safety follow-up duration, event collection, severity grading, or whether participants could contribute more than one event. The counts should therefore be read within their own listed safety groups rather than combined with the primary outcome.
The record also lists serious-event terms with percentages: hypertensive crisis (medication non-compliance), 14.3%; gastrointestinal bleed, 12.5%; diuretic-induced hypokalemia, 12.5%; and diverticulitis with recto-vaginal fistula, 12.5%. The record does not make clear in this listing how these percentages relate to the arm-level counts or what denominators apply to each term. They should not be interpreted as arm-specific rates or as evidence of comparative risk.
In general, event counts alone do not show whether one treatment has a higher risk than another. Interpretation depends on consistent definitions, observation time, denominators, and uncertainty around comparisons. No comparative safety analysis is reported in the registry record.
13. What the Result Does, and Does Not, Mean
The registry result establishes that the posted primary endpoint count was 6 in each vitamin E dose arm at 24 weeks. The endpoint definition was normal transaminases, meaning AST <=32 or ALT <=35 U/L. The associated denominators were 7, 6, and 8 for the 200 IU/day, 400 IU/day, and 800 IU/day arms, respectively. These are descriptive details about the posted results.
The counts do not establish that the doses are equivalent. A finding of equal counts is not the same as a formal equivalence or non-inferiority result, which would require a prespecified margin and an appropriate analysis. Neither is reported in the registry record. The counts also do not establish that one dose is superior, because no dose-group contrast or uncertainty estimate is posted.
The result does not show how the endpoint changed from baseline, whether participants met the threshold before treatment, or how enzyme values evolved during treatment. It does not answer the listed secondary questions about AST, ALT, GGT, or liver fat because numerical findings for those outcomes are not reported in the posted results. Nor does it compare vitamin E with an untreated, placebo, or diet-and-exercise-only group.
In general, randomized assignment helps make treatment groups comparable, but the interpretation of a trial still depends on complete outcome reporting, analysis populations, and uncertainty estimates. The registry identifies the study as randomized and gives arm-level outcome counts, but does not report the analysis plan, missing-data approach, or comparative estimates. Those omissions limit what can be concluded statistically from the record.
The safety listings describe serious and other adverse events by group and record no deaths in the listed groups. They do not provide a statistical comparison, a clear explanation of event-term denominators, or enough detail to infer comparative safety. The posted safety counts should be interpreted as descriptive registry entries rather than as evidence that risks are the same or different across doses.
Overall, the registry supports a narrow reading: it records a small set of 24-week biochemical response counts across three vitamin E dose groups. It does not, on its own, establish a dose-response relationship, quantify the precision of treatment differences, or determine the clinical importance of the observed counts.
14. Why This Trial Matters Statistically
This trial is statistically notable because it asks a dose-comparison question using a threshold-based binary endpoint in a small randomized study. The endpoint count is easy to communicate, but counts without comparative estimates or uncertainty can invite stronger conclusions than the data reporting supports. Equal observed counts across dose groups do not establish equivalence, and different denominators make raw counts especially important to interpret in context.
The registry also illustrates why analysis populations and participant flow matter. Enrollment is recorded as 22, while the primary endpoint denominators are 7, 6, and 8, and the safety listings use 7, 7, and 8. The registry does not explain these differences. A clear account of who was randomized, who completed treatment, and who contributed each outcome would help readers understand the scope of the results.
Unmasked treatment assignment is another design feature relevant to interpretation. Laboratory thresholds may be less subjective than some outcomes, but the record does not describe measurement procedures or protections against assessment bias. Transparent reporting of outcome collection and analysis methods would help assess how the design affects the endpoint.
More broadly, a registry entry can preserve useful details about trial design and results while still lacking the information needed for an inferential reading. Comparative effect estimates, confidence intervals, analysis populations, missing-data methods, and multiplicity plans would help distinguish a descriptive pattern from evidence about differences among doses. Their absence is not evidence of a particular result; it marks the limits of what can be learned from the posted record.
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 primary outcome is presented as a count at a single time point, with no baseline values or change-from-baseline analysis reported. It is therefore not possible to tell from the primary endpoint counts whether participants entered the study above or below the thresholds, or how close their measured enzyme values were to those cutoffs. The definition also combines AST and ALT using an “or” rule, and the record does not report how many participants qualified through each measure.
The trial has small arm-level endpoint denominators, and the registry provides no confidence intervals or formal comparisons. This limits assessment of precision and makes the counts sensitive to individual participant outcomes. No inference about equivalence, superiority, or a dose-response pattern is justified by the counts alone.
The registry does not report baseline characteristics, adherence, treatment discontinuation, participant flow, missing-data handling, or the analysis population. It also does not report the randomization method or allocation concealment. The incomplete brief summary and the lack of a described separate diet-and-exercise randomized arm leave some aspects of the intervention context unclear.
The safety denominators differ from the primary endpoint denominators, and the registry does not explain why. The listed serious-event percentages do not have clearly stated denominators in the safety information. Follow-up details and comparative safety analyses are not reported in the registry record, limiting interpretation of those figures.
Finally, the registry lists several secondary outcomes but does not report their numerical results or the statistical plan for evaluating multiple outcomes. The trial's own sample-size justification is also not reported in the registry record. These limitations concern the information available in the registry entry and should not be taken as claims about analyses that may have been conducted elsewhere.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Treatment for Non-Alcoholic Fatty Liver With Different Doses of Vitamin E — NCT01792115.
- Registry record last updated 2020-11-04; status last verified 2020-03-05.
- Results first posted 2020-10-19.
- 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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19. Record Summary
The registry record describes NCT01792115, a completed randomized, unmasked, parallel-group phase 2 trial sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases. Total enrollment is listed as 22. The study compared vitamin E at 200 IU/day, 400 IU/day, and 800 IU/day for 24 weeks, with an optional open-label extension using 800 IU/day for up to 120 weeks described in the arm information.
The primary outcome was the number of participants with normal transaminases at 24 weeks, defined as AST <=32 or ALT <=35 U/L. The registry reports 6 participants meeting this definition in each dose group, with endpoint denominators of 7, 6, and 8, respectively. It does not report a comparative statistical analysis or uncertainty estimates for this outcome.
Secondary outcomes include changes in AST, ALT, GGT, and liver fat. Safety listings report serious events, other adverse events, and deaths by group, but do not include a comparative safety analysis. The statistical plan, sample-size justification, missing-data methods, and analysis populations are not reported in the registry record.