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 Testosterone Replacement in Men With Diabetes and Obesity (NCT01127659), a randomized phase 4 study. The primary outcome is Insulin Sensitivity.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01127659 |
| Phase | Phase 4 |
| Condition | Hypogonadism |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Double |
| Enrollment | 137 |
| Arms in the primary outcome | n/a |
| Lead sponsor | University at Buffalo |
| Results posted | Yes |
2. Clinical Question
Population
Men with diabetes and hypogonadotropic hypogonadism, and obese non-diabetic men with hypogonadotropic hypogonadism, were assigned to testosterone or placebo. The registry also describes eugonadal comparison groups with diabetes or obesity who were not treated. The record does not report the criteria used to define these groups or further eligibility details.
Intervention
Testosterone was the active drug intervention for participants with hypogonadotropic hypogonadism. The registry describes separate testosterone groups for men with diabetes and obese non-diabetic men. Dose, formulation, route, and treatment schedule are not reported in the registry record.
Comparator
Placebo was the randomized comparator for participants with hypogonadotropic hypogonadism, with separate placebo groups for men with diabetes and obese non-diabetic men. The eugonadal groups were described as untreated; they are not described as randomized placebo comparators.
Primary question
The primary outcome was insulin sensitivity, assessed as glucose infusion rate during hyperinsulinemic-euglycemic clamps from baseline to 6 months. The registry record does not report the outcome values or a treatment-effect estimate, so the direction and precision of any difference cannot be evaluated from this record.
3. Trial Design
This was a Phase 4, randomized, double-masked, parallel-group study sponsored by the University at Buffalo. The registry lists enrollment of 137 and a completed status. The study began in 2010-05, with primary completion in 2015-03. These are registry-level details; they do not establish how many participants contributed data to a particular outcome analysis.
The randomized comparisons were between testosterone and placebo among men with hypogonadotropic hypogonadism. The record describes those comparisons separately for participants with diabetes and obese non-diabetic participants. It also lists eugonadal participants with diabetes and eugonadal obese participants who were not treated. Those groups may describe comparison populations, but the record does not say they were randomized or masked. Their presence should therefore not be interpreted as extending the randomized treatment contrast to all listed groups.
The registry lists testosterone and placebo as drug interventions. It does not report the testosterone regimen, placebo formulation, treatment adherence, or details of masking procedures. The parallel-group designation means the study is recorded as comparing groups assigned to different interventions rather than as a crossover design; further implementation details are not reported in the registry record.
The stated study purpose included examining testosterone deficiency and treatment effects across body-response indicators in men with diabetes or obesity. Insulin sensitivity is the primary outcome, and body composition is listed as a secondary outcome. The registry does not report the full protocol, planned comparisons for every group, or the analysis population. Accordingly, the design description identifies the broad structure of the study but does not resolve how all intended comparisons were carried out.
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 | Diabetes With HH: Testosterone | Diabetes With HH: Placebo | Obese Testosterone | Obese Placebo | Eugonadal Diabetes | Eugonadal Obese |
|---|---|---|---|---|---|---|
| STARTED | 22 | 22 | 12 | 10 | 50 | 21 |
| COMPLETED | 20 | 14 | 10 | 6 | 50 | 21 |
| NOT COMPLETED | 2 | 8 | 2 | 4 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Glucose infusion rate in HE clamps was measured
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.
Only the first 6 of 7 groups are shown.
| Characteristic | Unit | Diabetes With HH: Testosterone | Obese With HH: Testosterone | Obese With HH: Placebo | Diabetes With HH: Placebo | Eugonadal Diabetes | Eugonadal Obese |
|---|---|---|---|---|---|---|---|
| Participants analysed | 22 | 12 | 10 | 22 | 50 | 21 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 22 | 12 | 10 | 22 | 50 | 21 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Continuous | years | 54 (SD 7) | 46 (SD 9) | 53 (SD 7) | 54 (SD 9) | 52 (SD 9) | 50 (SD 8) |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 22 | 12 | 10 | 22 | 50 | 21 |
| Region of Enrollment: United States | participants | 22 | 12 | 10 | 22 | 50 | 21 |
6. Primary Endpoint
The registry lists the primary outcome as Insulin Sensitivity, measured over baseline to 6 months.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mg/kg fat free mass/min |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is insulin sensitivity, expressed as a mean in mg/kg fat free mass/min. The registry describes measurement by HE clamps at baseline and 6 months and identifies the measured quantity as glucose infusion rate. A hyperinsulinemic-euglycemic clamp is a controlled physiological procedure: insulin is infused while glucose is adjusted to maintain a target blood-glucose level. In general, the glucose infusion required under the clamp conditions is used as an indicator of insulin-mediated glucose handling. This is a general explanation of the measurement, not a claim about the trial’s observed findings.
Expressing the rate relative to fat-free mass accounts for body composition in the stated unit. The planned timeframe makes change between baseline and 6 months relevant to the endpoint. However, the registry record does not report the numerical means, standard deviations, change estimates, confidence intervals, or a treatment comparison for this outcome. It also does not give sufficient detail to assess the clamp protocol or the exact analytic definition used for the reported endpoint.
The registry indicates that the primary outcome was not reduced to one comparison because it involved several categories or time points. That matters when interpreting any single contrast: the endpoint label alone does not establish which group comparison, time point, or summary would represent the prespecified primary test. Those details are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies insulin sensitivity as the primary outcome and describes its measurement through glucose infusion rate during HE clamps from baseline to 6 months. It does not report an outcome value, a between-group estimate, a confidence interval, or a significance test. Consequently, this record does not establish whether the testosterone and placebo groups differed, how large any difference was, or how precisely it was estimated.
The record lists a continuous outcome summarized as a mean with standard deviation. Those descriptors tell the reader the intended form of measurement and dispersion, but they do not substitute for numerical results. Without the means, standard deviations, group sizes contributing to the outcome, and analysis details, the treatment contrast cannot be reconstructed from the registry information. No recalculated effect estimate is available from the record.
The study includes distinct clinical contexts: diabetes with hypogonadotropic hypogonadism and obesity without diabetes with hypogonadotropic hypogonadism. The randomized testosterone-versus-placebo comparisons are described within those contexts. A result from one context would not automatically establish the same result in the other. The eugonadal groups are described as untreated, so comparisons involving them would answer a different question from a randomized testosterone-versus-placebo comparison. The registry record does not report estimates for any of these contrasts.
Several features needed for a fuller statistical reading are absent. The exact primary contrast, model, adjustment variables, handling of repeated measurements, and participant-level analysis set are not reported in the registry record. Neither are missing-data counts or methods. The record lists zero analysis entries, which means it supplies no analysis-level results to interpret; it does not by itself show that no analysis was conducted outside the registry.
Statistical significance and clinical importance cannot be assessed without an estimated effect and its uncertainty, and the registry does not report either. Even a reported p-value alone would not describe the size or precision of an effect; the estimate and confidence interval would be needed for that assessment. No conclusion about benefit, lack of benefit, or harm should be drawn from the absence of posted primary-outcome results.
The enrollment figure is a registry description, not an outcome-specific analysis denominator. It cannot establish how many participants completed treatment, had clamp measurements at both time points, or contributed to a particular comparison. Thus, neither precision nor attrition can be inferred from enrollment alone.
9. Statistical Methods Explained
For a continuous outcome such as insulin sensitivity, a mean describes the center of the observed measurements, while a standard deviation describes their spread around that mean. In general, these are descriptive summaries. A treatment comparison requires an estimate of how the groups differ, with an uncertainty measure such as a confidence interval. The registry record identifies the mean and standard deviation as the outcome summary but does not report numerical summaries or a treatment-effect estimate.
What does a confidence interval tell the reader?
In general, a confidence interval gives a range of estimates compatible with the data and the statistical procedure used. A narrower interval indicates greater precision than a wider interval, all else equal. It does not mean that every value inside the interval is equally likely, nor does it establish clinical importance. No confidence interval for insulin sensitivity is reported in the registry record, so the precision of a treatment comparison cannot be assessed.
Why does the comparison need to be specified?
A study can measure the same endpoint in several groups and at several time points. The question answered by comparing testosterone with placebo among men with diabetes is not identical to the question answered in obese non-diabetic men. Comparing either randomized group with an untreated eugonadal group is different again, because the registry describes those participants as not treated rather than as randomized placebo recipients. The registry notes multiple categories or time points and does not reduce the primary outcome to one comparison. The exact primary contrast and testing procedure are not reported in the registry record.
What does randomization contribute?
In general, random assignment is intended to make treatment groups comparable with respect to measured and unmeasured characteristics, on average, before treatment. This supports a causal interpretation of an appropriately analyzed randomized comparison, subject to issues such as adherence, missing outcomes, and deviations from the assigned intervention. Randomization does not guarantee identical groups in a particular study, and it does not remove the need to report the analysis population and methods. The registry describes randomization for the testosterone and placebo groups with hypogonadotropic hypogonadism, but it does not report allocation procedures or the analysis approach.
The study is recorded as double-masked. In general, masking can reduce the risk that knowledge of assignment influences participant behavior, clinical management, or outcome assessment. How masking was implemented and maintained is not reported in the registry record. The eugonadal groups are described as untreated, and the record does not state that they were masked or randomized.
How should the planning assumptions be read?
The record describes planning illustrations based on the observed effect, using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. For non-time-to-event illustrations, the stated quantity is participants per arm for 80% power; the record also distinguishes illustrations for other power targets. Such calculations are hypothetical planning aids, not observed trial results and not observed power. The effect to detect is described as a stated fraction of the observed effect, but the record does not give the numerical observed effect needed to assess those illustrations. It also does not report that these planning assumptions were the trial’s original design assumptions.
In general, a planning calculation estimates how much information a future study might need under specified assumptions. The estimate depends on the effect size chosen, variability, significance level, allocation, and statistical model. If assumptions differ from the eventual study or future research question, the resulting planning figure may not be appropriate. These illustrations cannot recover missing primary-outcome estimates or demonstrate that the completed study had a particular level of power.
Why do variability and model choice matter?
For continuous outcomes, variation among participants affects how precisely a group mean or difference can be estimated. The standard deviation is one summary of that variation. If the outcome distribution is skewed, has influential extreme values, or differs substantially in variability between groups, a simple normal-based analysis may need careful assessment. This is a general statistical consideration; the registry does not report distributional diagnostics or the analysis model used for insulin sensitivity.
Measurements at baseline and follow-up are related within a participant. In general, an analysis can account for that relationship, for example by modeling follow-up values while adjusting for baseline, or by analyzing change from baseline. Different approaches can produce different estimates and uncertainty. The registry gives the timeframe as baseline to 6 months but does not report which approach was used. It also does not state whether the analysis included all available measurements or only participants with measurements at both time points.
The endpoint is expressed per unit of fat-free mass. In general, this scaling can help make measurements more comparable across participants with different body composition, but interpretation still depends on the precise measurement and analysis definitions. The registry record does not provide further technical details on the clamp procedure, data processing, or any covariate adjustment.
Finally, a p-value, if available, would address compatibility of the observed data with a specified null hypothesis under a statistical model; it would not measure the probability that the null hypothesis is true. Because no analysis-level p-value or estimate is reported, there is no inferential result to interpret. The registry’s design fields and outcome description clarify what was intended to be studied, but they do not supply the evidence needed to judge the observed treatment effect.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies insulin sensitivity as the primary outcome and body composition as a secondary outcome. It also notes that the primary outcome involves several categories or time points and is not reduced to one comparison. When multiple comparisons or outcomes are examined, the chance of at least one false-positive finding can increase if each is tested without an appropriate plan. In general, trial protocols may address this through a hierarchy of outcomes, adjusted significance thresholds, or other prespecified procedures. The registry record does not report a multiplicity strategy, so it is not possible to determine how any family of tests was handled.
The statistical analysis plan, exact primary contrast, and any interim-analysis plan are not reported in the registry record. No interim analysis should be inferred from the completion status or the available design description. The record also does not report whether analysis choices were prespecified before results were examined.
Missing data can affect both the size and comparability of treatment groups. In general, loss of follow-up or unavailable clamp measurements may reduce precision, and the consequences depend on why measurements are missing and how the analysis handles them. The registry does not report missing-outcome counts, reasons for missingness, imputation procedures, or sensitivity analyses. It also does not identify an intention-to-treat, per-protocol, or other analysis population.
Enrollment of 137 is not an outcome-specific denominator and should not be treated as proof that all enrolled participants contributed to the primary analysis. The number analyzed for insulin sensitivity, and the number with measurements at each time point, are not reported in the registry record. Without those details and the analysis plan, robustness to missing data and multiplicity cannot be assessed.
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 |
|---|---|---|---|
| Diabetes With HH: Testosterone | 0 | 22 | 0.0% |
| Diabetes With HH: Placebo | 0 | 22 | 0.0% |
| Obese With HH: Testosterone | 0 | 12 | 0.0% |
| Obese With HH: Placebo | 0 | 10 | 0.0% |
| Eugonadal Diabetes | 0 | 50 | 0.0% |
| Eugonadal Obese | 0 | 21 | 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 |
|---|---|
| Diabetes With HH: Testosterone | 0 of 22 |
| Diabetes With HH: Placebo | 0 of 22 |
| Obese With HH: Testosterone | 0 of 12 |
| Obese With HH: Placebo | 0 of 10 |
| Eugonadal Diabetes | 0 of 50 |
| Eugonadal Obese | 0 of 21 |
The registry lists serious adverse events and other adverse events separately for the diabetes with hypogonadotropic hypogonadism groups, the obese with hypogonadotropic hypogonadism groups, and the eugonadal groups. The reported serious-event count is 0 in each listed group, and the reported other-event count is also 0 in each listed group. The record lists participants at risk for each category and group, but these safety denominators should be read within their stated group labels rather than combined into an overall total.
A reported count of 0 means that no events in that category were recorded in the registry entry for that group. It does not prove that the underlying risk is zero, that no event occurred outside the reporting window, or that the treatment has no safety concerns. Rare events are especially difficult to assess when the number of participants observed is limited. The registry does not list serious-event terms, and it does not provide event-level timing or participant narratives.
Deaths are recorded as null rather than as a numerical count. Their status is therefore not reported in the registry record; null should not be interpreted as zero deaths. The safety entry does not provide enough information to evaluate duration of exposure, completeness of adverse-event ascertainment, or differences in risk between treatment groups. These figures describe what the registry reports, not a comprehensive safety conclusion.
12. What the Result Does, and Does Not, Mean
The trial addresses a clinically specific research question: insulin sensitivity in men with diabetes or obesity and hypogonadotropic hypogonadism, with testosterone compared with placebo within the hypogonadism groups. The primary endpoint is based on glucose infusion rate during HE clamps from baseline to 6 months. These design details identify the intended measurement and randomized comparisons, but they do not reveal the observed outcome.
The registry record does not report numerical primary-outcome results, a treatment-effect estimate, an uncertainty interval, or an analysis-level significance test. It therefore cannot show whether insulin sensitivity changed, whether changes differed between testosterone and placebo, or how precise any such difference was. No statement that testosterone was effective or ineffective follows from a missing result.
The same caution applies to comparisons involving the untreated eugonadal groups. Those groups differ in the way the registry describes their treatment and assignment, so a contrast with a randomized treatment group would not have the same interpretation as the randomized testosterone-versus-placebo comparison. The record does not report estimates for those comparisons or explain their role in the analysis.
Statistical evidence and clinical relevance are related but distinct. In general, the estimated size of an effect and its uncertainty help assess whether a result is compatible with a small or larger difference; clinical relevance also depends on the meaning of the measure and the context in which it is used. Since the registry does not provide the estimate or its precision, neither question can be answered from this record.
The enrollment figure, completed status, and safety counts do not fill this evidence gap. Enrollment is not the same as the number analyzed for the primary endpoint, and zero recorded event counts do not establish absence of risk. The registry record is useful for describing the study’s broad design, endpoint, and reported safety entries, but its posted information is insufficient to judge the primary treatment effect.
13. Why This Trial Matters Statistically
This trial is statistically notable for combining randomized treatment comparisons with additional untreated comparison groups. The randomized comparisons concern testosterone versus placebo among men with hypogonadotropic hypogonadism, separately in the diabetes and obese non-diabetic contexts. The eugonadal groups are described as untreated, so they do not have the same assignment structure. Keeping these contrasts distinct is essential: randomization supports a different interpretation from a comparison between groups that were not described as randomized.
The outcome is a physiological continuous measure collected at baseline and 6 months. Repeated measurements can provide information about change, but a sound interpretation depends on how baseline and follow-up are incorporated, how missing measurements are handled, and which contrast is designated primary. Those analytic details are not reported in the registry record. The record also notes multiple categories or time points without reducing the primary outcome to a single comparison, which leaves the precise inferential target unclear.
Another statistical lesson is the distinction between a registry description and a reported result. A completed study with a stated primary outcome is not, by itself, evidence of a treatment difference. Without outcome estimates and uncertainty, readers cannot assess direction, magnitude, precision, or compatibility with no difference. Planning illustrations based on an observed effect are not a substitute for the observed effect itself, and they do not represent observed power.
The safety listing illustrates a related point: recorded zero counts are bounded by the groups and event categories reported, while null death entries remain unreported rather than zero. Careful interpretation preserves those distinctions instead of making broader claims than the registry supports. Here, the design is informative, but missing analysis results limit what can be concluded statistically.
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 main limitation of the registry information is the absence of numerical results for the primary endpoint. No group means, standard deviations, between-group estimates, confidence intervals, or p-values are reported. As a result, the treatment contrast cannot be evaluated for direction, magnitude, or precision. The registry also does not report outcome-specific denominators, so the enrollment figure cannot establish how many participants contributed to the endpoint analysis.
The exact primary comparison is not clear from the record, which notes multiple categories or time points without reducing the endpoint to one comparison. The analysis model, baseline adjustment, handling of repeated measurements, and definition of the analysis population are not reported. Missing-data counts and methods are also absent, limiting assessment of attrition and potential bias.
The study includes diabetes and obese non-diabetic groups, as well as eugonadal groups described as untreated. The registry does not fully explain the planned analytic role of every group or provide estimates for comparisons across them. The randomized testosterone-versus-placebo contrast should not be conflated with comparisons involving untreated groups.
Important intervention details, including dose, formulation, route, schedule, and adherence, are not reported in the registry record. Nor are the clamp protocol details, outcome data-processing procedures, or multiplicity strategy. These omissions restrict reproducibility and make it difficult to assess whether the reported endpoint and intended analyses were implemented as planned.
Safety interpretation is limited by the lack of event descriptions and the null entries for deaths. The registry reports zero serious and other adverse-event counts in the listed groups, but it does not establish completeness of ascertainment or duration of exposure. These limitations concern the registry information available and should not be treated as proof that the underlying study lacked analyses or procedures.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Testosterone Replacement in Men With Diabetes and Obesity — NCT01127659.
- Registry record last updated 2022-11-29; status last verified 2022-10.
- Results first posted 2017-03-07.
- 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 describes a completed Phase 4, randomized, double-masked, parallel-group study sponsored by the University at Buffalo, with enrollment of 137. It began in 2010-05 and reached primary completion in 2015-03. The study concerned men with diabetes or obesity and hypogonadotropic hypogonadism, with testosterone and placebo interventions. Eugonadal diabetes and obese groups are also listed as untreated comparison groups.
Insulin sensitivity was the primary outcome, expressed as a mean in mg/kg fat free mass/min and measured by glucose infusion rate during HE clamps from baseline to 6 months. Body composition is listed as a secondary outcome. The registry record does not report numerical primary-outcome results or analysis-level estimates, and it does not identify the primary contrast or analysis population in sufficient detail for an inferential assessment.
Serious and other adverse-event counts are recorded as 0 in each listed group. Death counts are null and therefore not reported in the registry record. Overall, the registry describes the trial’s broad design and outcome but does not provide the results needed to assess the primary treatment effect.