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 Oral Contraceptives, Insulin Resistance and Cardiovascular Risk Profile in Pre-Menopausal Women (NCT01475513), a non-randomized phase 4 study. The primary outcome is Change From Baseline in Insulin Sensitivity.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01475513 |
| Phase | Phase 4 |
| Condition | Insulin Sensitivity, Cardiovascular Risk, Perimenopausal Disorder |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 47 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Virginia Commonwealth University |
| Results posted | Yes |
2. Clinical Question
Population
The registry describes pre-menopausal women and identifies groups of African-American women and Caucasian women. The listed conditions include insulin sensitivity, cardiovascular risk and perimenopausal disorder. The record does not give further eligibility details or report the characteristics of the participants who contributed data to the primary outcome.
Intervention
The listed intervention is Ortho Cyclen®, a drug. The study’s brief description says its purpose is to examine whether birth control pills change heart disease risk and how the body handles blood sugar when given to different women. Further details about how the drug was administered are not reported in the registry record.
Comparator
The two described groups are African-American women and Caucasian women. These are group labels, not evidence of a randomized treatment comparison. The record identifies the allocation as non-randomized and does not describe an untreated or active control group. Therefore, differences between the groups cannot automatically be interpreted as effects caused by treatment.
Primary question
The primary endpoint is change from baseline in insulin sensitivity, measured using a frequently sampled intravenous glucose tolerance test, from baseline to 6 months. The endpoint description says higher values indicate better insulin sensitivity. The record does not report the observed changes, their confidence intervals, or an estimated comparison between groups, so the size and precision of any observed change cannot be assessed from the registry record.
3. Trial Design
The registry classifies this as a Phase 4, non-randomized, parallel-group study with no masking. It lists an enrollment of 47 and describes groups of African-American women and Caucasian women. The listed intervention is Ortho Cyclen®. The registry does not establish in the outcome information how participants were assigned to the groups or provide enough detail to characterize the groups as comparable treatment arms.
Non-randomized allocation is important when interpreting a group comparison. In general, random assignment helps balance measured and unmeasured participant characteristics across groups. Without it, characteristics associated with both group membership and an outcome may contribute to an observed difference. The record does not report an adjustment strategy or other method intended to address such differences. The groups should therefore be read as non-randomized, not as a like-for-like control comparison.
The primary outcome is defined as change in insulin sensitivity between baseline and 6 months. The record also lists secondary outcomes concerning insulin response, glucose effectiveness, disposition index, fasting insulin, fasting glucose, insulin and glucose areas under the curve, and systolic blood pressure. These measures broaden the set of questions addressed, but the registry does not report their numerical results.
The study is marked completed, with a start date of 2011-11 and a primary completion date of 2014-05-28. The registry record does not report the recruitment process, participant flow, treatment adherence, protocol deviations, or the timing and content of any follow-up beyond the stated outcome timeframe. Those details would be needed to understand how the planned measurements were carried out and which participants contributed to each analysis.
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 | African-American Women | Caucasian Women |
|---|---|---|
| STARTED | 20 | 26 |
| COMPLETED | 17 | 16 |
| NOT COMPLETED | 3 | 10 |
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 | African-American Women | Caucasian Women | Total |
|---|---|---|---|---|
| Participants analysed | 18 | 17 | 35 | |
| Age, Continuous | years | 20.3 (SD 3.43) | 21.6 (SD 3.92) | 21.0 (SD 3.68) |
| Sex: Female, Male: Female | Participants | 18 | 17 | 35 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 18 | 0 | 18 |
| Race (NIH/OMB): White | Participants | 0 | 17 | 17 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| Region of Enrollment: United States | Participants | 18 | 17 | 35 |
6. Primary Endpoint
The registry lists the primary outcome as Change From Baseline in Insulin Sensitivity, measured over Baseline, 6 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | min ^ -1 / mIU / L |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change from baseline in insulin sensitivity, measured with a frequently sampled intravenous glucose tolerance test (FSIVGTT). The stated timeframe is baseline to 6 months, and the unit is min ^ -1 / mIU / L. The endpoint is described as a mean, with a 95% confidence interval as the dispersion measure. The registry states that higher values indicate better insulin sensitivity.
Insulin sensitivity describes how responsive the body is to insulin in handling glucose. As a general statistical point, a continuous measure can capture degrees of change rather than reducing observations to categories. A baseline-to-follow-up change focuses on how the measurement differs over time, but interpreting that change depends on the actual values, how they were calculated, and the participants included.
The record identifies why this endpoint is relevant to the study’s stated interest in blood-sugar handling. However, it does not report the observed mean change or confidence interval. There is consequently no registry result from which to assess the direction, magnitude, or precision of the primary endpoint change. The endpoint definition alone describes what was intended to be measured; it is not evidence of what was observed.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a study question and outcome definitions, but it does not report a numerical primary-outcome result. Although the primary endpoint is specified as mean change in insulin sensitivity from baseline to 6 months, no observed mean change or 95% confidence interval is reported. The record also lists zero analyses. The direction, size, and precision of the primary endpoint result therefore cannot be evaluated from the registry information.
This distinction matters because an endpoint definition is not an outcome finding. Knowing that higher insulin-sensitivity values indicate better insulin sensitivity explains the scale’s stated direction, but it does not show whether values increased or decreased during the study. Without an estimate and its uncertainty, it is not possible to judge whether a measured change was small or large, or whether the data are compatible with a range of possible effects.
Even if group-specific results were available, the study’s non-randomized allocation would limit causal interpretation. In general, groups that differ in characteristics at baseline may also differ in their subsequent outcomes. An observed difference could reflect treatment, group composition, other influences, or a combination of these. The registry does not report a statistical adjustment plan or results that would clarify how such differences were handled. The race-based group labels should not be treated as randomized treatment assignments.
The registry lists 16 outcome measures and names secondary measures related to insulin response, glucose effectiveness, disposition index, fasting insulin and glucose, areas under the curve, and systolic blood pressure. A list of outcomes does not establish that every measure was analyzed, and the record does not provide numerical findings for these outcomes. No multiplicity strategy is reported, so the record does not indicate how the potential for false-positive findings across multiple analyses was addressed.
The posted serious adverse-event counts are zero in each listed group, and deaths are also recorded as zero. These figures describe the reported serious-event categories and the at-risk denominators shown in the safety record. They do not establish that no adverse effects of any kind occurred. The registry does not report the broader non-serious adverse-event profile in the registry record for this analysis.
Overall, the record supports a description of the study design, intended primary measure, and reported serious-event counts. It does not support a conclusion about the observed effect on insulin sensitivity or cardiovascular risk. Such conclusions require outcome estimates and appropriate uncertainty information, neither of which is reported for the primary endpoint in the registry record.
9. Statistical Methods Explained
The registry describes the primary measure as a mean of a continuous outcome and specifies a 95% confidence interval as its dispersion measure. The primary outcome is change in insulin sensitivity between baseline and 6 months. The registry record does not report the numerical estimate or interval. The concepts below are general explanations of how these statistics are usually interpreted, not claims about analyses conducted in this study.
What does a mean change represent?
For a continuous outcome, a mean summarizes values by their arithmetic average. A mean change summarizes the average within-participant difference between two time points when change is calculated for participants with measurements at both times. That summary can help describe the direction and typical size of change in the analyzed group. It does not show how much individual participants varied, and it can be influenced by the distribution of values and by which participants have usable measurements.
The registry identifies a baseline-to-6-month change but does not give the calculation details beyond that description. For example, it does not report the analysis population, whether the endpoint was calculated for each participant before averaging, or how missing follow-up measurements were handled. Those details are not reported in the registry record and should not be inferred from the endpoint title alone.
How should a confidence interval be read?
In general, a confidence interval communicates uncertainty around an estimate. A narrower interval indicates greater precision under the assumptions of the statistical method; a wider interval indicates less precision. It is not a range containing a fixed proportion of individual participant measurements, and it does not by itself establish whether an estimate is clinically important. Interpretation depends on the estimate, the interval, the outcome scale, and the study design.
The record specifies a 95% confidence interval but does not provide its bounds or the associated mean change. It is therefore not possible to assess precision for the primary endpoint or determine which values remain compatible with the observed data. The confidence level stated in the endpoint description is a method specification, not a reported result.
Why does the allocation matter?
As a general principle, randomization can reduce systematic differences between comparison groups by using chance to assign participants. In a non-randomized study, group membership may be related to participant characteristics that also relate to the outcome. A raw group difference can then combine treatment-associated change with pre-existing differences or other influences. Statistical adjustment can sometimes address measured differences, but it cannot guarantee removal of unmeasured confounding.
This study is classified as non-randomized, and the described groups are African-American women and Caucasian women. The record does not report an adjustment method or the information needed to evaluate baseline comparability. Accordingly, any hypothetical between-group contrast should not be read as a randomized treatment effect. The available record does not report such a contrast in any case.
What does the outcome list tell the reader?
The registry lists 16 outcome measures and identifies several secondary outcomes. In general, examining multiple outcomes can answer different scientific questions, but repeated statistical testing can increase the chance of at least one apparently notable result arising by chance. A prespecified multiplicity strategy may control or otherwise address that issue. The registry record does not report such a strategy or numerical analyses for the listed measures. The number of registered outcomes should not be mistaken for the number of completed statistical tests.
How should planning calculations be distinguished from results?
In general, sample-size calculations describe the amount of information a future or planned study might need under stated assumptions. A planning illustration based on an observed effect is not observed power and does not demonstrate that a study had adequate precision. The stated planning assumptions refer to a two-sided significance level of 0.05, equal allocation, a normal approximation, and an effect expressed as a fraction of the observed effect; the record does not report numerical sample-size illustrations in the registry record.
Planning assumptions do not replace an outcome estimate, confidence interval, or analysis of the enrolled participants. Because no primary analysis result is reported, no conclusion about the observed endpoint or its uncertainty can be drawn from planning information. The actual registry record also does not report its own sample-size justification.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 16 outcome measures, including the primary insulin-sensitivity measure and secondary measures related to insulin response, glucose handling, fasting measures, areas under the curve, and systolic blood pressure. Multiple outcomes can be scientifically useful, but they also raise a general statistical issue: testing many hypotheses can increase the chance of a false-positive finding. A prespecified approach might control that risk, distinguish primary from exploratory analyses, or otherwise explain how results are interpreted. A multiplicity method is not reported in the registry record.
The record lists zero analyses and does not report numerical outcome results. It therefore does not show which outcomes were analyzed, what statistical tests were used, or how any multiplicity strategy was applied. The registered count of outcome measures should not be interpreted as proof that every measure was tested.
Missing-data handling is not reported in the registry record. There is no information about missing baseline or follow-up measurements, withdrawals, or how incomplete observations were handled. The analysis population is also not reported. Without these details, the reader cannot determine how many participants contributed to the primary endpoint analysis or whether the analyzed participants differed from those enrolled.
The record does not report an intention-to-treat or per-protocol approach, a prespecified statistical analysis plan, or interim analyses. These omissions do not establish that such procedures were absent from the study; they mean they are not reported in the registry record. They limit assessment of the analysis process and the scope of any conclusions that could be drawn from results.
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 |
|---|---|---|---|
| African-American Women | 0 | 20 | 0.0% |
| Caucasian Women | 0 | 26 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| African-American Women | 0 of 20 |
| Caucasian Women | 0 of 26 |
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 |
|---|---|
| African-American Women | 0 of 20 |
| Caucasian Women | 0 of 26 |
The registry’s serious adverse-event record lists zero serious events among the African-American women group, with 20 at risk, and zero among the Caucasian women group, with 26 at risk. Deaths are recorded as zero in each group. These are group-specific entries; they should be read with their listed denominators rather than combined into a new total.
In general, a zero count means no event was recorded in the specified category for the listed group. It does not prove that the underlying risk is zero, and it does not establish that no adverse effects occurred. The figures concern serious adverse events and deaths as reported in the record; they do not describe all possible symptoms, non-serious events, or longer-term outcomes.
The registry does not report additional safety details, such as event descriptions beyond the serious-event categories available, severity gradings, relatedness assessments, or exposure duration for these safety counts. The zero counts should therefore be interpreted narrowly as the reported serious-event and death entries, not as a complete assessment of safety.
12. What the Result Does, and Does Not, Mean
The study’s stated aim is to examine whether birth control pills change heart disease risk and how the body handles blood sugar in different women. Its primary endpoint is a baseline-to-6-month change in insulin sensitivity measured by FSIVGTT. The registry also lists related metabolic and cardiovascular outcomes. These details show what the study set out to assess, but the registry record does not report quantitative results for the primary endpoint or the listed secondary outcomes.
Consequently, the record does not establish the direction or size of an observed change in insulin sensitivity. It also does not show how precise any estimate was, because no primary endpoint confidence interval is reported. Without those results, it is not possible to assess whether the data support a particular interpretation of the endpoint. The endpoint description that higher values indicate better insulin sensitivity is a statement about the measure, not a result.
The non-randomized design further limits causal interpretation. In general, differences between the described groups may reflect factors associated with group membership, not only the intervention. The record does not report an adjustment strategy or a randomized control comparison that would support stronger causal attribution.
The serious adverse-event entries report zero events and zero deaths in each listed group. Those entries should not be generalized to all adverse effects or taken as proof of no risk. They cover only the reported categories.
In short, the registry record allows readers to identify the study’s design, groups, intervention listing, endpoint definition, and limited serious-event counts. It does not report the evidence needed to determine the observed effect on insulin sensitivity or cardiovascular risk. No conclusion that the intervention did or did not change these outcomes follows from the design description alone.
13. Why This Trial Matters Statistically
This study is statistically notable for the questions it links: insulin sensitivity, blood-sugar handling, and cardiovascular risk in pre-menopausal women. Its primary endpoint is a continuous measure, described as a mean change from baseline to 6 months. Continuous measures can preserve information about degrees of change, while the confidence interval specified for the endpoint would ordinarily help readers judge the precision of an estimate. The numerical estimate and interval are not reported in the registry record.
The non-randomized allocation is central to interpreting any comparison. General statistical reasoning distinguishes an association between group membership and outcome from a causal treatment effect. Without random assignment or a reported strategy for addressing confounding, differences between the described groups cannot be attributed to treatment alone. This is especially important because the groups are described by race rather than as randomized treatment assignments.
The study also registers multiple outcomes spanning insulin response, glucose measures, and blood pressure. That breadth can reflect a multidimensional research question, but it makes transparent analysis reporting important. The registry record does not report outcome analyses or a plan for handling multiplicity, missing data, or analysis populations. Those omissions leave uncertainty about how the registered questions were evaluated.
The completed status and enrollment entry document study activity, but they do not substitute for outcome estimates. The record is therefore useful for understanding the intended design and measurement framework, while its lack of reported analysis results prevents statistical assessment of the primary question. This distinction is a practical reminder that trial registration, endpoint specification, and results reporting serve different purposes.
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.
A major limitation for interpretation is that the registry record does not report the primary endpoint estimate or its 95% confidence interval. The primary question concerns change in insulin sensitivity from baseline to 6 months, but the available record gives only the measure’s definition and direction. There is no numerical result with which to assess magnitude or precision.
The study is non-randomized and describes groups by race. The record does not report an adjustment strategy or sufficient baseline information to assess group comparability. Consequently, the design description does not support treating group differences as effects caused by the listed intervention. The record also does not clarify the relationship between the intervention listing and each described group in enough detail to establish a like-for-like treatment comparison.
Further limitations concern reporting. Although 16 outcome measures are listed, numerical results are not reported, and no analyses are listed. The registry does not report a statistical analysis plan, multiplicity approach, missing-data method, analysis populations, participant flow, or information about adherence and protocol deviations. These details are not reported in the registry record, so their absence from this account should not be taken as evidence that the study did not address them elsewhere.
The safety record reports serious adverse-event and death counts, but does not provide a complete adverse-event profile. The scope of the reported safety information is therefore limited. Finally, the registry entry does not report a sample-size justification or numerical planning illustrations. The enrollment entry alone cannot establish the precision or adequacy of an outcome analysis.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Oral Contraceptives, Insulin Resistance and Cardiovascular Risk Profile in Pre-Menopausal Women — NCT01475513.
- Registry record last updated 2018-08-08; status last verified 2018-07.
- Results first posted 2018-07-10.
- 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 Phase 4, non-randomized, unmasked, parallel-group study with an enrollment of 47. The listed intervention is Ortho Cyclen®. The described groups are African-American women and Caucasian women. The study’s stated purpose concerns heart disease risk and blood-sugar handling in different women.
The primary endpoint is mean change from baseline to 6 months in insulin sensitivity measured by FSIVGTT, with higher values indicating better insulin sensitivity. A 95% confidence interval is specified, but no numerical endpoint result or analysis is reported in the registry record. The record lists 16 outcome measures and identifies secondary metabolic and blood-pressure outcomes.
The serious adverse-event entries report zero events and zero deaths in each group. These counts do not represent a complete account of all adverse effects. Important analysis details, including missing-data handling, analysis populations, and multiplicity methods, are not reported in the registry record.