Metabolic and Neuro-Endocrine Effect of Treating PCOS in Adolescents: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Metabolic and Neuro-Endocrine Effect of Treating PCOS in Adolescents (NCT03981861), a na phase 2, phase 3 study. The primary outcome is Oral Glucose Tolerance Test.

2. Clinical Question

The clinical question is therefore about the measurements recorded in a group of adolescents with PCOS receiving the combination treatment, including whether glucose and insulin measurements changed over the stated follow-up. Because the registry identifies a single group and does not report a separate comparator, any before-and-after pattern would not by itself establish that the treatment caused the change. Natural changes over time, other influences, and measurement variability cannot be separated from a treatment effect using a single-group comparison alone.

3. Trial Design

The registry describes a completed study with a single-group model and lists its phase as phase 2 and phase 3. Enrollment is 12. Allocation is recorded as NA, and masking is listed as none. The intervention is metformin and spironolactone, and the arm description identifies the group as the “Overall Study.” There is no like-for-like control arm described in the registry record.

The study began on 2016-07-02, and the primary completion date is 2018-07-09. The status is completed. The stated purpose was to examine the effect of a combination of low-dose metformin and spironolactone on functional brain MRI, menstrual regulation, and metabolism in adolescents with PCOS. The primary outcome measure is an oral glucose tolerance test, described as measuring glucose and insulin at baseline and 2 hours after 75g of glucola, with change assessed from baseline to 6 months.

A single-group design can describe measurements collected during treatment and changes over time in the enrolled group. It does not offer a concurrent comparison for estimating what would have happened over the same period without treatment. That distinction matters when interpreting any change: a before-and-after difference can reflect treatment, but can also reflect other time-related influences or measurement variability.

The registry record does not report more detailed design information such as treatment dose, adherence procedures, eligibility criteria, or whether participants had additional care during follow-up. It also does not report an analysis plan or numerical outcome results. Consequently, the design description supports a limited account of the study structure, rather than a detailed assessment of how its results were generated or how representative the participants may be.

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

Reasons for not completing this period:

5. Baseline Characteristics

The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.

6. Primary Endpoint

The registry lists the primary outcome as Oral Glucose Tolerance Test, measured over Change Measures: Baseline & 6 Months.

The primary endpoint is titled “Oral Glucose Tolerance Test.” It is a continuous measure reported as a mean with standard deviation, in mg/dL. Its description says that glucose and insulin are measured at baseline and 2 hours after 75g of glucola. The stated timeframe is change from baseline to 6 months.

An oral glucose tolerance test is used to assess how glucose levels respond after a glucose-containing drink. Recording glucose and insulin provides measurements related to the body’s response during the test. Comparing measurements over time can describe whether the recorded values changed during the study period. In general, the mean describes the average measurement in a group, while the standard deviation describes the spread of individual measurements around that average. These summaries are useful for describing the group, but they do not show every participant’s measurement or the distribution’s full shape.

The registry record does not include the actual baseline or follow-up means, standard deviations, or a numerical change estimate. It also does not clarify in the endpoint description whether glucose and insulin are reported as separate outcome values or how a change is calculated for each. The endpoint definition therefore identifies what was intended to be measured and when, but not the observed result or its precision.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registry describes the primary outcome as continuous, with a mean and standard deviation, measured in mg/dL. These summaries answer different descriptive questions. The mean gives the average measurement in the group; the standard deviation indicates how dispersed individual measurements are around that average. General interpretation: a small standard deviation relative to the mean indicates measurements are more concentrated, while a larger one indicates greater spread. Neither summary identifies the range of observed values or describes all features of the distribution.

What does a change over time represent?

The endpoint timeframe is change from baseline to 6 months. In a repeated-measure setting, a change can be described by comparing each participant’s measurements across assessments, or by comparing group summaries at the assessment times. These approaches do not necessarily produce the same estimate. The registry record does not report which approach was used, how the change was calculated, or whether the reported measure refers to glucose, insulin, or separate summaries for both. It also does not post the measurements or a numerical change estimate.

General explanation: a change estimate is most informative when its definition is explicit. For example, an analysis should make clear which measurement is subtracted from which, which participants contribute to the calculation, and how missing observations are treated. These details matter because an average change calculated from participants with measurements at both times may represent a different subset from a comparison of group-level averages. The registry record does not report these analytic details, so no particular calculation method should be assumed.

How should uncertainty be understood?

General explanation: a confidence interval expresses uncertainty around an estimated quantity. It indicates a range of values that are compatible with the data and the method’s assumptions. A narrow interval conveys more precision than a wide interval, while neither guarantees that the estimate is free from bias. The registry record does not report a confidence interval for the primary endpoint, or any estimate to which such an interval could be attached.

A p-value, when reported, addresses how unusual data would be under a specified null model and assumptions. It does not measure the size or clinical importance of an effect, and it does not establish causation. No primary endpoint p-value is reported in the registry record. Because no estimate, uncertainty interval, or test result is posted, the primary outcome cannot be assessed for statistical evidence or precision from this record.

What does the design permit?

The study is listed as single group, with allocation NA and no masking. General explanation: a within-group assessment can describe how measurements differ over time in the participants observed. A concurrent comparator helps distinguish changes associated with the intervention from changes that might have occurred over time for other reasons. The registry record does not identify a separate control group. Therefore, even if a change estimate were posted, it would be a before-and-after description rather than a randomized treatment contrast.

Masking is recorded as none. This is a design descriptor, not a result. General explanation: when participants or study personnel know the treatment being received, some outcomes or study procedures may be more susceptible to expectation or assessment effects than others. The registry record does not detail who knew treatment assignments, how outcome measurement was conducted, or whether any protections against measurement bias were used. It would be inappropriate to infer those procedures from the masking label alone.

How do planning illustrations differ from results?

The stated planning assumptions describe illustrations based on an observed effect: a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. The assumptions also specify that the effect to detect is a stated fraction of the observed effect. For time-to-event planning, the illustrations use a total event count; for other outcomes, they use participants per arm. These are planning scenarios, not observed trial outcomes and not observed power.

General explanation: sample-size planning asks how much information a future study might need for a specified design and target effect under stated assumptions. It does not show that the study under discussion had that design, that the assumed effect is reliable, or that the analysis achieved a particular probability of detecting an effect. Here, the registered design is single group, while the planning assumptions refer to equal allocation between two arms. The illustrations should therefore not be mistaken for a description of the registered design or for evidence of a randomized comparison. The registry record does not report the trial’s own sample-size justification.

The record lists five outcome measures and zero analyses. That distinction is important: an outcome’s presence in the registry is not a numerical result, and a planned or registered endpoint is not evidence that a particular analysis was completed or posted. The registry record does not report the statistical model, covariates, distributional assumptions for the endpoint, handling of repeated measurements, or any adjustment for multiple analyses. No such choices can be reconstructed from the endpoint’s mean-and-standard-deviation label.

In general, over-dispersion occurs when observed variability exceeds what a chosen statistical model assumes. Accounting for it can prevent uncertainty from being understated in analyses where it is relevant. The primary measure is described as continuous and summarized by a mean and standard deviation; the record does not report a model that would permit assessing whether over-dispersion was considered. This concept should not be read as a claim that over-dispersion occurred in this study.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists five outcome measures and zero analyses. The primary outcome is identified as an oral glucose tolerance test. The registry record does not report whether the other measures were secondary outcomes, how they were related to the primary measure, or which analyses were planned for them. It also does not report a multiplicity strategy, such as adjustment of significance thresholds or a hierarchy for interpreting outcomes. Without that information and without posted analyses, the risk of interpreting chance findings across multiple outcomes cannot be assessed.

The registry record does not report how missing data were handled. It does not state whether all enrolled participants contributed measurements at baseline and 6 months, whether any observations were excluded, or whether an imputation or other missing-data method was used. Enrollment of 12 does not establish the number of observations available for any endpoint analysis. The number included in the primary analysis is not reported in the registry record.

The analysis population is also not reported. The record does not specify whether analyses were based on all enrolled participants, participants who began treatment, participants with measurements at both time points, or another defined group. These are meaningful distinctions: the population analyzed determines which participants the resulting estimate describes. Because the study is single group, the record also does not describe an intention-to-treat comparison between randomized groups.

These omissions do not demonstrate that multiplicity or missing-data procedures were absent; they mean the procedures are not reported in the registry record. They limit reproducibility and prevent assessment of whether the posted outcome analysis, if available elsewhere, followed a prespecified plan.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Deaths

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 0% reporting threshold.

The registry reports the safety figures for the “Overall Study” group. Serious adverse events are listed for 0 of 12 at risk; other adverse events are listed for 0 of 12 at risk; deaths are listed as 0. These are registry-reported counts, not estimates of the chance of an event in a broader population.

A count of zero in the registry record means no events are recorded in that category for the group and reporting period represented by the record. It does not establish that an event is impossible, nor does it show how carefully events were monitored or how complete the reporting was. The record does not describe event definitions, severity assessment procedures, follow-up completeness, or the duration of safety surveillance beyond the study dates.

The safety figures should also be read in the context of the enrollment of 12 and the single-group design. They do not provide a comparative safety estimate against an untreated or alternative-treatment group. The registry record does not list top serious adverse event terms. The counts therefore describe what is registered, but they do not support a broad conclusion about safety or comparative risk.

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

The record establishes that a completed, single-group study examined metformin and spironolactone in adolescents with PCOS. It identifies the oral glucose tolerance test as the primary outcome, describes measurements of glucose and insulin at baseline and 2 hours after 75g of glucola, and specifies a change timeframe from baseline to 6 months. It also records enrollment of 12 and reports zero serious adverse events, zero other adverse events, and zero deaths in the overall group.

The registry record does not report numerical primary outcome results or statistical analyses. It therefore does not show whether glucose or insulin measurements increased, decreased, or remained similar over the stated timeframe. There is no reported effect estimate or confidence interval to indicate the size or precision of any change, and no reported p-value to assess statistical evidence under a stated test.

Even if before-and-after estimates were available, the single-group design would limit causal interpretation. A change within the group would not isolate the contribution of treatment from other changes over time. The record does not identify a concurrent comparison group, and it does not report random allocation or masking.

The safety counts are limited registry reports, not proof that treatment has no adverse effects. Similarly, the absence of posted outcome analyses is not evidence that no measurements were taken; it means the registry record does not provide numerical analyses for interpretation. The study’s broad aims include functional brain MRI, menstrual regulation, and metabolism, but the record does not give numerical findings for those aims.

Accordingly, the record documents a study question and design, but it does not establish whether the intervention changed the primary measure, how precisely any change was measured, or whether any change was caused by treatment. No treatment recommendation follows from the information reported.

13. Why This Trial Matters Statistically

This study is statistically informative as an example of how design and reporting determine what can be concluded. The registry identifies a defined population, a treatment, a single-group model, and a primary continuous measure. Those details help frame the clinical question. At the same time, the absence of numerical results and analyses means the central statistical questions—how large any change was, how variable it was, and how precisely it was estimated—remain unanswered in the registry record.

The single-group design is especially important when interpreting measurements across time. A before-and-after pattern can describe the participants’ experience during the study, but without a concurrent comparator it cannot separate treatment-associated change from other influences that may occur over time. Recognizing that distinction prevents a within-group change from being mistaken for a controlled treatment effect.

The endpoint’s summary as a mean with standard deviation also illustrates why descriptive statistics and inferential statistics are not interchangeable. A mean describes the group’s average measurement, and a standard deviation describes spread. Neither, by itself, provides the uncertainty around a change estimate or a causal interpretation. Those assessments require results and methods that are not reported in the registry record.

The record also shows why registration details and posted analyses serve different purposes. An endpoint description tells readers what was intended to be measured; an analysis reports what was observed and how it was evaluated. The registry lists five outcome measures but zero analyses. That gap limits assessment of outcome reporting, missing data, multiplicity, and analytic choices.

Finally, planning illustrations should be distinguished from the trial’s observed evidence. Their assumptions describe hypothetical planning scenarios and do not convert a single-group study into a two-arm comparison or indicate observed power. Clear separation of design, planning, safety counts, and outcome results is essential for a balanced statistical reading.

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 registry record provides limited information for evaluating this study’s results. Although it identifies an oral glucose tolerance test and a timeframe from baseline to 6 months, it does not report the numerical endpoint values, change estimate, confidence interval, or test results. It also lists five outcome measures and zero analyses. The primary outcome’s results and the findings for the other stated study aims therefore cannot be assessed from the registry record.

The single-group design has no separately described control arm. It can support description of measurements over time in the enrolled group, but it cannot by itself distinguish treatment effects from other influences that change over time. Allocation is recorded as NA and masking as none. The record does not provide further details about outcome assessment procedures or steps taken to reduce bias.

Enrollment is 12, but the number of participants contributing data to the primary endpoint is not reported in the registry record. Eligibility criteria, participant characteristics, adherence, treatment dose, and the handling of incomplete follow-up are also not reported. Without these details, the representativeness of the enrolled group and the completeness of the endpoint data cannot be evaluated.

The registry record does not report the statistical analysis plan, analysis population, missing-data methods, multiplicity procedures, or a sample-size justification for the trial itself. Planning illustrations based on observed effects are not a substitute for those details and do not establish observed power. The record also does not describe the methods used to collect and classify adverse events. These limitations restrict reproducibility and the scope of conclusions that can be drawn from the registered information.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Metabolic and Neuro-Endocrine Effect of Treating PCOS in Adolescents — NCT03981861.
• Registry record last updated 2021-02-23; status last verified 2021-02.
• Results first posted 2021-02-23.
• Data retrieved from ClinicalTrials.gov on 2026-11-09.
• Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.

18. Record Summary

NCT03981861 is a completed, single-group study titled “Metabolic and Neuro-Endocrine Effect of Treating PCOS in Adolescents.” It lists phase 2 and phase 3, enrollment of 12, no masking, and metformin and spironolactone as the intervention. The primary outcome is an oral glucose tolerance test, described as measuring glucose and insulin at baseline and 2 hours after 75g of glucola, with change assessed from baseline to 6 months.

The registry record reports zero serious adverse events, zero other adverse events, and zero deaths in the overall study group. It lists five outcome measures but zero analyses. Numerical primary outcome results, uncertainty estimates, and analysis methods are not reported in the registry record. The single-group design does not provide a like-for-like control comparison, so the registered information does not establish a treatment effect.