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 Effect of Medium Chain Fatty Acids on Cognitive Function During Acute Hypoglycemia in Patients With Type 1 Diabetes (NCT00592072), a randomized na study. The primary outcome is Immediate Verbal Memory.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00592072 |
| Phase | NA |
| Condition | Diabetes Mellitus, Type 1 |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | Quadruple |
| Enrollment | 12 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Yale University |
| Results posted | Yes |
2. Clinical Question
Population
People with type 1 diabetes mellitus. The registry record lists an enrollment of 12 participants. It does not provide further eligibility details or a description of the participants’ demographic or clinical characteristics.
Intervention
Medium-chain fatty acids, identified as octanoic and decanoic acid. The study’s stated aim was to examine whether the brain could use these fatty acids or their metabolites as an alternative fuel during acute hypoglycemia.
Comparator
Splenda, identified in the registry as a placebo control. The registry record does not give further details about the control solution or how the intervention and comparator were administered.
Primary question
Whether immediate verbal memory, measured during acute hypoglycemia, differed with medium-chain fatty acid administration compared with the placebo control. The registry record describes a cognitive-function study and a primary endpoint, but it does not report a single comparison estimate for that endpoint.
The study’s broader rationale was that medium-chain fatty acids might provide a rapidly absorbed, non-carbohydrate fuel source and that the brain might use them, or their metabolites, during hypoglycemia. The proposed clinical question therefore concerns cognitive performance under a specific metabolic challenge, rather than long-term cognitive change or the prevention of hypoglycemia.
The registry identifies a randomized crossover design. In general, a crossover study compares interventions within the same participants, which can reduce the influence of stable differences between individuals. That design also means that details such as intervention order, any period between interventions, and the handling of possible carryover can matter to interpretation. Those details are not reported in the registry record.
The primary outcome is described as immediate verbal memory, with a specified timeframe of 90 minutes. The record’s outcome description refers more broadly to cognitive tests and to performance during hypoglycemia, but it does not provide a single posted result comparing the intervention with the control for immediate verbal memory. The clinical question is therefore clear from the study description, while the registry record does not establish an answer to it.
3. Trial Design
The registry record identifies this as a randomized, quadruple-masked crossover study sponsored by Yale University. It lists an enrollment of 12 and a completed study status. The record classifies the phase as not applicable. It names two interventions: medium-chain fatty acids, specified as octanoic and decanoic acid, and Splenda as the placebo control.
Random allocation indicates that assignment was intended to use a chance-based process. In a crossover design, participants receive more than one intervention, allowing comparisons to be made within participants. This structure can be useful when the outcome varies substantially between people, because each participant can serve as their own comparison. However, the registry record does not state the intervention sequence, the number or order of study periods, or whether an interval separated periods.
Quadruple masking indicates that the registry describes the study as masked across four roles, but it does not identify those roles or explain how masking was maintained. The record also does not describe the allocation procedure, whether allocation was concealed, or how treatment identity was handled during data collection and analysis. These implementation details are not reported in the registry record.
The study’s stated purpose was to assess whether the brain could use medium-chain fatty acids or their metabolites as an alternative fuel during acute hypoglycemia in people with type 1 diabetes. The primary endpoint is listed as immediate verbal memory, measured at 90 minutes. The outcome description also mentions cognitive testing such as digit symbol substitution, everyday attention, telephone book searching, and map searching. It describes a scale with a lowest score of 0 and a highest score of 25, with higher scores representing improvement.
The registry lists nine outcome measures, but no analyses. It does not provide a single intervention-versus-control estimate for the primary endpoint, nor does it describe a statistical analysis plan, interim analyses, or the methods used to address the crossover structure. The enrollment rationale includes a stated planning claim based on a validation-span result, but the record does not provide enough detail to infer additional design assumptions.
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.
First Sequence
| Stage | MCT Intervention First, Then Placebo | Placebo Intervention First, Then MCT Intervention |
|---|---|---|
| STARTED | 6 | 6 |
| COMPLETED | 6 | 6 |
| NOT COMPLETED | 0 | 0 |
Wash Out Period
| Stage | MCT Intervention First, Then Placebo | Placebo Intervention First, Then MCT Intervention |
|---|---|---|
| STARTED | 6 | 6 |
| COMPLETED | 5 | 5 |
| NOT COMPLETED | 1 | 1 |
Reasons for not completing this period:
| Reason | MCT Intervention First, Then Placebo | Placebo Intervention First, Then MCT Intervention |
|---|---|---|
| Lost to Follow-up | 1 | 1 |
Second Sequence
| Stage | MCT Intervention First, Then Placebo | Placebo Intervention First, Then MCT Intervention |
|---|---|---|
| STARTED | 5 | 5 |
| COMPLETED | 5 | 5 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: With the validation span test, a decrease in cognitive performance from euglycemia to hypoglycemia (22+/-2.3 vs 13.4+/-2.5) or a difference of 8.6 has been reported. Using this, a sample size of 12 will provide 80% power to detect a 23% (i.e. 2 unit) attenuation of the effect of hypoglycemia on cognitive performance.
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: The baseline number of subjects reflects the number of subjects with baseline data
| Characteristic | Unit | Overall Number of Subjects |
|---|---|---|
| Participants analysed | 11 | |
| Age, Continuous | years | 34.8 (SD 8.9) |
| Sex: Female, Male: Female | Participants | 6 |
| Sex: Female, Male: Male | Participants | 5 |
6. Primary Endpoint
The registry lists the primary outcome as Immediate Verbal Memory, measured over 90 minutes.
| Element | Registry entry |
|---|---|
| Result type | Least Squares Mean |
| Measure of spread | Standard Error |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is immediate verbal memory, recorded in units on a scale and assessed at 90 minutes. The registry describes cognitive testing during acute hypoglycemia and says the scale ranges from 0 to 25, with a higher score indicating better performance. It also names tasks covering memory, attention, and visual or practical information-search activities. The endpoint is intended to capture cognitive performance during the study condition, rather than a long-term change in cognition.
Memory is relevant to the stated study question because the investigators wanted to determine whether the brain could use medium-chain fatty acids, or their metabolites, as an alternative fuel during acute hypoglycemia. A cognitive measure can assess performance under that condition directly. The registry record does not explain why immediate verbal memory was selected over the other cognitive tasks, whether it was the sole primary measure, or how it was scored in practice beyond the scale range and direction.
The endpoint is identified as a least-squares mean with standard error as its dispersion measure. In general, a least-squares mean is an estimate from a statistical model, and a standard error describes the estimate’s sampling precision. The model used to produce this endpoint is not reported in the registry record. Nor does the record post a single primary-outcome estimate, uncertainty interval, or test result comparing medium-chain fatty acids with placebo. The endpoint and its measurement are described, but its comparative result is not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes the study’s design, intended comparison, and primary endpoint, but it does not provide a single primary-outcome comparison. It lists nine outcome measures and zero analyses. It also indicates that the primary outcome has several categories or time points and was not reduced to one comparison. As a result, the record does not support a direct estimate of how immediate verbal memory differed between the medium-chain fatty acid intervention and placebo.
The endpoint description gives the measurement scale and the direction of scoring: the scale ranges from 0 to 25, and higher scores indicate improvement. It identifies the outcome as a least-squares mean with standard error and specifies a 90-minute timeframe. These details explain what a posted estimate would represent, but they are not themselves evidence of an intervention effect. Without a reported comparative estimate and its uncertainty, the size and precision of any difference cannot be assessed from the registry record.
The record’s description of the study hypothesis is not a result. It states that medium-chain fatty acids were being investigated as a possible alternative fuel source during acute hypoglycemia and that the study aimed to assess cognitive performance. A hypothesis describes what a study set out to examine; it does not establish that an intervention changed an outcome. The registry record does not report a result that would confirm or refute the stated hypothesis.
The crossover design makes the unreported analysis details especially relevant. In general, a crossover comparison depends on how repeated measurements and treatment periods are handled. Possible influences include period effects, sequence effects, and carryover from one intervention period to another. The registry record does not describe the sequence, periods, or statistical handling of these considerations, so they cannot be evaluated from the posted information.
The enrollment rationale states that a sample size of 12 would provide 80% power to detect a 23% attenuation, described as 2 units, based on a cited validation-span decrease from 22+/-2.3 to 13.4+/-2.5 and a difference of 8.6. This is a stated planning rationale, not a report of the observed primary endpoint or a substitute for the missing treatment comparison. The record does not explain whether the stated rationale was tied to the final primary endpoint analysis or whether its assumptions were met.
The serious adverse event entries list zero affected participants in both intervention groups. Other adverse events are recorded for 3 of 12 participants in the medium-chain fatty acid group and 0 of 12 in the placebo group. These are descriptive registry counts; the record does not give event descriptions in the adverse-event summary or establish why the events occurred. They should not be treated as an estimate of comparative risk, particularly without information about event definitions, observation periods, or the crossover periods contributing to the counts.
Overall, the posted record supports a description of the research question and design, but not a conclusion about the primary outcome’s comparative effect. The absence of a single primary comparison means that neither the direction nor the precision of an intervention-associated difference can be read from this record. It also does not establish whether the intended analyses were performed elsewhere.
9. Statistical Methods Explained
The registry identifies the primary outcome as a continuous measure reported as a least-squares mean with standard error. It does not report a single numerical comparison for that outcome. The concepts below explain how such statistics are generally interpreted; they do not describe an analysis that can be confirmed from this registry record.
What does a least-squares mean represent?
In general, a least-squares mean is a model-based estimate of an average outcome. Unlike a simple arithmetic mean, it can reflect adjustments or structure included in a statistical model. The estimate’s interpretation depends on which terms the model includes and how those terms are defined. For a crossover study, a model might need to account for repeated measurements and study periods, but the registry record does not identify the model used or say whether any such terms were included.
The endpoint’s measurement scale ranges from 0 to 25, and a higher score is described as an improvement. An estimate on this scale would be interpreted in the context of that scoring direction. The registry record lists the dispersion measure as standard error, but a standard error is not the same as the spread of individual participants’ scores. It describes the sampling precision of an estimated quantity under the model used.
What would a confidence interval add?
In general, a confidence interval presents a range of estimates compatible with the data under specified statistical assumptions. It communicates uncertainty around an estimate and helps readers assess which effect sizes remain plausible. A point estimate alone does not convey that precision. The registry record does not post a confidence interval for the primary comparison, or a single primary comparison estimate from which one could be interpreted.
A confidence interval would not, by itself, establish that a result is clinically important or explain why an observed difference occurred. Its meaning depends on the outcome scale, the model, and the data. In this case, no primary-outcome interval is reported in the registry record, so the precision of the intervention-versus-control comparison cannot be assessed.
How does a crossover design affect analysis?
In general, crossover studies observe participants under multiple interventions. This makes within-participant comparisons possible and can account for stable characteristics that differ between individuals. But repeated observations from the same participant are related, so an analysis should reflect that dependence rather than treating every measurement as independent.
Period and sequence can also matter. A period effect is a change associated with when a measurement occurs, apart from the assigned intervention. A sequence effect concerns the order in which interventions are received. Carryover refers to an influence from an earlier intervention that persists into a later period. These are general design considerations, not confirmed features of the study’s analysis. The registry record does not report the sequence, number of periods, interval between interventions, or the statistical method used to address repeated observations or possible carryover.
What does the stated planning rationale mean?
The registry’s endpoint description states that a validation-span decrease from 22+/-2.3 to 13.4+/-2.5, or a difference of 8.6, had been reported. It then states that a sample size of 12 would provide 80% power to detect a 23% attenuation, described as 2 units, of the hypoglycemia effect. This is a planning statement recorded in the endpoint description. It is not an observed treatment effect, and it does not establish how much power the completed study had for the primary endpoint as ultimately analyzed.
In general, power is a design-stage probability of detecting an effect of a specified size under assumed conditions, if that effect is present. It depends on features such as the outcome variability, analysis method, significance threshold, and target effect. A planning claim cannot be used to infer an observed result. The record does not provide a full sample-size justification or enough detail to verify all assumptions behind the stated rationale.
Why does over-dispersion matter in general?
Over-dispersion is a general concern for some outcome models when the observed variation exceeds what the chosen model expects. If not accounted for, standard errors and tests can be misleading. The primary endpoint is described as a continuous measure, and the registry record does not report an over-dispersion assessment or identify a model for which that issue is relevant. It should not be assumed to have been present or assessed in this study.
What can a significance test say?
In general, a significance test evaluates how compatible observed data are with a specified null hypothesis under a statistical model. A p-value does not measure the probability that the null hypothesis is true, and it does not communicate the magnitude or clinical importance of an effect. Interpretation should consider the estimate and its uncertainty as well as the test result. The registry record does not report a primary-outcome test result or a single primary comparison, so no significance conclusion can be drawn from the posted primary outcome information.
These methods concepts clarify what would be needed to interpret a continuous endpoint in a crossover trial. The registry record supplies the endpoint label, scale, direction, timeframe, and dispersion type, but not the model specification or comparative estimate needed to assess the primary result.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists nine outcome measures, while the primary outcome description refers to several cognitive categories or time points. The record explicitly indicates that the primary outcome was not reduced to one comparison, and it lists zero analyses. Consequently, there is no single primary comparison available in the registry record to interpret alongside the other outcome measures.
When a study evaluates multiple outcomes, tasks, time points, or comparisons, general statistical practice considers the possibility of multiplicity: the more opportunities there are to identify a result, the more important it is to understand which analyses were prespecified and how conclusions account for multiple testing. The registry record does not report a multiplicity strategy, a hierarchy of outcome testing, or which measures were designated as primary beyond naming immediate verbal memory. It is not possible to determine whether any adjustment or other strategy was planned or used.
The registry record also does not report missing-data counts, reasons for missingness, or methods for handling missing outcomes. In a crossover study, information about whether participants completed each intervention period and contributed measurements under both conditions would be relevant. Those details are not reported in the registry record.
Analysis populations are not described. The record does not state whether analyses followed assigned treatment, included only participants completing all periods, or used another population definition. Nor does it report exclusions or a flow of participants through the study. Without these details, readers cannot assess the relationship between enrollment and the analyzed population.
These omissions do not establish that the study lacked a statistical plan or that data were missing. They mean only that multiplicity procedures, missing-data handling, and analysis populations are not reported in the registry record. The lack of a single posted comparison further limits assessment of how the primary endpoint was analyzed.
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 |
|---|---|---|---|
| MCT Intervention | 0 | 12 | 0.0% |
| Placebo Intervention | 0 | 12 | 0.0% |
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 |
|---|---|
| MCT Intervention | 3 of 12 |
| Placebo Intervention | 0 of 12 |
Most frequent non-serious adverse event terms
| Event term | Organ system | MCT Intervention | Placebo Intervention |
|---|---|---|---|
| Gastrointestinal Symptoms | Gastrointestinal disorders | 3 of 12 | 0 of 12 |
The registry’s serious adverse event entries report zero affected participants in the medium-chain fatty acid group and zero in the placebo group. Each group lists 12 participants at risk for serious events. The record does not list serious adverse event terms.
For other adverse events, the registry lists 3 affected participants among 12 at risk in the medium-chain fatty acid group, and 0 affected participants among 12 at risk in the placebo group. These counts describe what the record reports; they do not establish that the intervention caused the events or that the absence of recorded events in the comparator group indicates no risk.
The adverse-event summary does not give event descriptions, severity details, timing, or attribution. The registry record also does not report deaths. Because the design is crossover, the listed group labels should not automatically be read as independent parallel groups or as a complete account of participant exposure. The record does not explain how adverse-event observation periods were assigned or counted.
These figures are descriptive safety information, not a formal comparative safety analysis. The small enrollment and missing detail limit what can be inferred from the counts. The registry record does not provide enough information to assess event type, timing, or relationship to the interventions.
12. What the Result Does, and Does Not, Mean
The record shows that a randomized, quadruple-masked crossover study was conducted to examine cognitive performance during acute hypoglycemia in people with type 1 diabetes. It identifies medium-chain fatty acids as the intervention, Splenda as the placebo control, and immediate verbal memory as the primary endpoint. It also describes the scale and the direction in which scores are interpreted.
What the record does not show is a single primary-outcome estimate comparing the interventions. The registry lists nine outcome measures and zero analyses, and the primary outcome is not reduced to one comparison. Therefore, the posted information cannot establish the size, direction, or precision of an intervention-associated difference in immediate verbal memory. The study’s hypothesis and planning rationale are not evidence of an observed effect.
The registry’s serious adverse event entries report no affected participants in either group, while other adverse events are listed for 3 participants in the medium-chain fatty acid group and none in the placebo group. Those counts do not by themselves establish whether events were caused by an intervention. Event descriptions and other context are not reported in the registry record.
The absence of a posted comparison should not be taken to mean that no analysis was conducted or that the interventions had no effect. It means that the registry record does not report an interpretable primary comparison. Results in a different record or publication cannot be inferred from the information presented in this registry entry.
More generally, a treatment comparison is best interpreted using an effect estimate, its uncertainty, the analysis method, and the population included. Here, the endpoint definition and trial design provide context for the question, but the missing result and analysis details prevent a statistical conclusion about the primary outcome. This is a limitation of what the registry record reports, not a claim about what may exist elsewhere.
13. Why This Trial Matters Statistically
This trial raises a statistical question that is more specific than whether cognitive performance changes during hypoglycemia. It asks whether the same participants’ performance differs between an intervention intended to provide medium-chain fatty acids and a placebo control. The crossover design makes within-participant comparisons central to the intended interpretation, so the analysis needs to reflect repeated measurements and the order in which conditions are experienced.
The registry record identifies a primary endpoint and a defined measurement scale, which helps specify what an outcome comparison would mean. It also gives a stated planning rationale based on a validation-span result and a proposed attenuation of the hypoglycemia effect. Keeping this rationale distinct from observed results is important: a planned detectable effect does not reveal the effect found in the completed study.
The record also illustrates why outcome structure matters. It lists nine outcome measures, and the primary outcome includes several categories or time points rather than one posted comparison. Without knowing which comparisons were prespecified and how multiplicity was handled, readers cannot assess how the outcome set shaped the analysis or interpretation.
Finally, design labels and endpoint definitions are not substitutes for results. Randomization and masking describe important aspects of study conduct, while a comparative estimate and its uncertainty are needed to assess the primary outcome. The registry record supplies the former context but not the latter. This distinction helps readers separate a well-defined research question from evidence that would answer it.
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 the registry record does not report a single primary-outcome comparison. It lists zero analyses and indicates that the primary outcome, which has several categories or time points, was not reduced to one comparison. Thus, the primary endpoint’s comparative estimate and precision cannot be evaluated from the posted record.
The endpoint description gives a scale range, scoring direction, timeframe, and summary-statistic type, but it does not provide the model specification or the statistical handling of the crossover design. The registry record does not report intervention order, study periods, any interval between periods, or how repeated observations and possible carryover were addressed. These details would help readers understand the assumptions behind a within-participant comparison.
Other analysis details are also absent. Multiplicity procedures, missing-data methods, analysis populations, participant flow, and interim analyses are not reported in the registry record. These omissions do not show that such procedures were not used; they limit what can be assessed from the record.
The enrollment was 12, and the registry’s planning rationale is stated in relation to a validation-span result and a target attenuation. The record does not give a full account of the assumptions behind that rationale or establish how closely it corresponded to the final analysis. The planning statement should not be treated as observed power or as evidence of an outcome.
The adverse-event information is also limited. The record gives counts but no event descriptions, timing, attribution, or further context. It does not report deaths. These details matter when interpreting descriptive counts, especially in a crossover design where participants may experience more than one study condition.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Effect of Medium Chain Fatty Acids on Cognitive Function During Acute Hypoglycemia in Patients With Type 1 Diabetes — NCT00592072.
- Registry record last updated 2015-01-22; status last verified 2015-01.
- Results first posted 2015-01-05.
- 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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18. Record Summary
The registry record describes a completed randomized, quadruple-masked crossover study sponsored by Yale University, with an enrollment of 12. It examined medium-chain fatty acids—octanoic and decanoic acid—against Splenda as a placebo control in people with type 1 diabetes, with the aim of studying cognitive performance during acute hypoglycemia.
Immediate verbal memory is listed as the primary endpoint, measured at 90 minutes. The record describes a scale from 0 to 25, with higher scores representing improvement, and identifies the summary as a least-squares mean with standard error. It lists nine outcome measures and zero analyses, and does not report a single primary comparison.
The serious adverse event entries show zero affected participants in each group. Other adverse events are listed for 3 of 12 participants in the medium-chain fatty acid group and 0 of 12 in the placebo group. Event details and a comparative primary-outcome result are not reported in the registry record.