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 Ramipril for the Treatment of Oligospermia (NCT01856361), a randomized na study. The primary outcome is Sperm Density in Infertile Men With Documented Oligospermia..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01856361 |
| Phase | NA |
| Condition | Oligospermia, Teratospermia, Asthenozoospermia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Quadruple |
| Enrollment | 2 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Weill Medical College of Cornell University |
| Results posted | Yes |
2. Clinical Question
Population
Infertile men with documented low sperm count, described in the record as oligospermia. The listed conditions also include teratospermia, asthenozoospermia, and male infertility.
Intervention
Ramipril, started at 2.5 mg and increased to 5 mg during the study, with treatment planned for 32 weeks.
Comparator
A placebo presented as a similar pill, with a planned dose increase during the study and a 32-week treatment period.
Primary question
Whether sperm density in men with documented oligospermia differed between the ramipril and placebo groups at 32 weeks. No outcome data were collected, so the comparison was not analyzed.
The study was intended to evaluate whether ramipril could affect sperm production, with sperm density designated as the primary endpoint. The registry summary also identifies sperm count, sperm shape, and motility as areas of interest. Listed secondary outcomes include total motile sperm count, total sperm count, sperm motility, morphology in the ejaculate, pregnancy rate, and hormonal profile.
The clinical question is therefore a comparison between assignment to ramipril and assignment to placebo in a population selected for low sperm count. It is not a comparison of treatment before and after use, and the registry does not report an analyzed contrast. The record describes the planned question and endpoints, but it does not establish whether ramipril changed sperm density or any secondary outcome.
3. Trial Design
The study is recorded as randomized, quadruple masked, and parallel-group. In a randomized study, assignment to treatment is intended to reduce systematic differences between groups; masking is intended to limit the influence of treatment knowledge on participants, care, or assessment. The record identifies the masking level but does not explain which groups of people were masked or how masking was maintained. The phase is listed as NA.
The planned comparison was between ramipril and placebo. The ramipril arm began at 2.5 mg at week zero and increased to 5 mg at the visit 4 weeks into the study, for a total of 32 weeks. The placebo arm was described as receiving a similar pill, with participants asked to take two pills starting at the visit 4 weeks into the study, also for a total of 32 weeks. The record does not report the allocation ratio.
Enrollment was 2. The study started in 2013-07, with primary completion recorded as 2016-06, and its status is TERMINATED. The registry explanation says data were not collected on the 2 participants because the principal investigator moved to a different practice and the study ended before results could be analyzed. The sponsor is Weill Medical College of Cornell University.
The record does not report a sample-size justification, a detailed statistical analysis plan, an interim-analysis plan, or procedures for allocation concealment. Those details cannot be inferred from the randomized and masked design labels. Most importantly, planned design features do not substitute for completed outcome collection: there is no reported randomized comparison of clinical results.
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 | Ramipril | Placebo |
|---|---|---|
| STARTED | 1 | 1 |
| COMPLETED | 1 | 1 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Data was not collected on the 2 participants as the principal investigator on this trial moved to a different practice and thus the study terminated before any results could be analyzed.
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 | Ramipril | Placebo | Total |
|---|---|---|---|---|
| Participants analysed | 1 | 1 | 2 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 1 | 1 | 2 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 1 | 1 | 2 |
6. Primary Endpoint
The registry lists the primary outcome as Sperm Density in Infertile Men With Documented Oligospermia., measured over 32 weeks.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is sperm density in infertile men with documented oligospermia, with a stated timeframe of 32 weeks. Sperm density describes the concentration of sperm in a semen sample. As a general statistical concept, it can serve as a quantitative measure related to sperm production and can be used to compare groups assigned to different interventions. Its interpretation depends on how the sample is collected and measured, and on how the endpoint is summarized and analyzed.
The registry record does not specify the unit, the measurement method, the statistical parameter, or the measure of dispersion for this endpoint. It also does not describe a threshold for a meaningful change. These omissions limit the detail with which a future estimate could be interpreted, even if outcome data were available.
No data were collected on the participants for the primary outcome, and no results were analyzed. Consequently, there is no reported sperm-density value, between-group estimate, confidence interval, or test result. The endpoint identifies what the trial intended to assess; it does not show what happened to sperm density during the study.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central statistical fact is that this terminated trial has no analyzed primary-outcome data. Although enrollment was 2 and the registry describes randomization to ramipril or placebo, it states that data were not collected on those participants and that the study ended before results could be analyzed. There is therefore no observed treatment effect to interpret for sperm density at 32 weeks.
No group-level sperm-density summaries, treatment contrast, confidence interval, or p-value are reported in the registry record. Without an estimate and its uncertainty, readers cannot assess the direction, size, or precision of a possible difference between the groups. The record also does not permit an assessment of whether the groups were comparable at baseline or whether the planned treatment schedule was completed.
The registry lists secondary outcomes, including sperm measures, pregnancy rate, and hormonal profile, but it reports no analyzed results for them. Their inclusion in the study plan is not evidence that they were measured or that an effect was found. The registry does not report results for these outcomes.
The adverse-event fields record 0 serious events and 0 other events among 1 participant at risk in each arm. These are limited counts, not a basis for a broad safety comparison. Death counts are not reported in the registry record. The safety entries do not compensate for the absence of efficacy outcome data.
The planned statistical framework for any sample-size illustrations describes a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. Such planning quantities are not observed power and do not establish that the trial could detect an effect. The record does not report a design-specific sample-size justification, and the lack of collected outcome data prevents estimation of an effect from this trial.
Accordingly, the registry supports a description of the intended comparison, study design, termination, and recorded adverse-event counts. It does not support a conclusion about whether sperm density or any secondary outcome differed between ramipril and placebo. The absence of an analyzed result is not evidence for either benefit or lack of benefit; it is an absence of outcome evidence from this trial.
9. Statistical Methods Explained
Statistical methods determine how a trial turns collected measurements into estimates and how much uncertainty to attach to those estimates. In this study, the record identifies a randomized parallel-group comparison, a primary endpoint, and a 32-week timeframe. It does not report the analysis procedures that would have been used for the primary or secondary outcomes. No outcome data were collected, so no trial estimate or inferential result is available to review.
Random assignment is generally used to support a fair comparison by making treatment allocation independent of participants’ measured and unmeasured characteristics in expectation. In a small study, however, randomization does not guarantee that the groups will be similar on every characteristic. The record gives an enrollment of 2 but does not report the allocation ratio, group baseline characteristics, or participant-level assignments. It is therefore not possible to assess balance or reconstruct the allocation process from the registry record.
A parallel-group design assigns participants to a treatment group for comparison with a separate group. The intended contrast is ramipril versus placebo. The record labels the study quadruple masked, but it does not specify which people were masked, how the masking was implemented, or whether it was maintained. Masking is generally intended to reduce the chance that knowledge of assignment influences behavior, treatment, assessment, or reporting. The label alone does not demonstrate that these risks were eliminated.
The primary outcome is sperm density at 32 weeks. To estimate a treatment contrast, investigators would need measured outcomes and a defined summary or model. The registry does not report whether the planned analysis would compare group means, use a transformed outcome, adjust for baseline sperm density, or use another method. These choices matter because the measurement scale, distribution, and handling of baseline values can affect both the estimate and its uncertainty. None should be assumed from the endpoint name.
A confidence interval is a general way to describe the precision of an estimated effect. A narrower interval indicates greater precision under the model used; a wider interval indicates greater uncertainty. A p-value, as a general concept, measures how compatible the observed data are with a specified null hypothesis under a statistical model. Neither statistic can be calculated or interpreted for the primary outcome from this registry record, because no outcome data or treatment-effect estimate is reported. The record also does not state a confidence-interval method or a planned hypothesis test.
The registry’s stated planning framework describes a two-sided significance level of 0.05, equal allocation between the arms, and a normal approximation. It describes planning illustrations based on a stated fraction of an observed effect, with participant counts per arm for ordinary outcomes and total event counts for time-to-event outcomes. These assumptions describe a planning exercise, not an analysis of trial outcomes. Sample-size illustrations are not observed power. The registry record does not report the trial’s own sample-size justification or identify an effect size used in its original design.
There is an important limitation in interpreting any observed-effect-based planning illustration alongside the outcome description: the registry says data were not collected on the 2 participants and that the study ended before results could be analyzed. The record does not explain how an observed effect was established for planning. Without a reported outcome estimate, the illustrations cannot be treated as evidence of an effect from this trial. They cannot show whether the intended study was adequately sized.
Over-dispersion is a general concern when outcome variability is greater than a model assumes. If present, it can make standard errors too small and statistical tests too optimistic unless the analysis accounts for it. The registry does not report an outcome distribution or any model, so there is no basis for determining whether over-dispersion is relevant to this endpoint in this study. More generally, model assumptions cannot be checked without observations.
Multiplicity refers to the added chance of false-positive findings when several outcomes or hypotheses are tested. The record lists multiple secondary outcomes, but it does not report a multiplicity-adjustment strategy, a hierarchy of hypotheses, or which outcomes would be confirmatory. Any statistical interpretation of multiple outcome tests would require those details and the actual results. Neither is available in the registry record.
Missing-data methods are also not reported. The primary-outcome description says data were not collected on the 2 participants because the study terminated before results could be analyzed. This is not a situation where a missing-data model can be assessed from the record: there are no collected primary-outcome observations to describe. The registry does not say whether any other measurements, visits, or safety assessments were completed, or how missing observations would have been handled under the planned analysis.
Finally, analysis populations are not reported. The record does not say whether the intended analysis would include all randomized participants, only participants with measured outcomes, or another defined group. These distinctions can affect the meaning of a treatment estimate. Since no participant outcome data were analyzed, there is no reported intention-to-treat, per-protocol, or other analysis population result. The statistical methods that can be described are therefore limited to the registered design and planning assumptions, not completed analysis procedures.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists five outcome measures and describes several secondary areas: total motile sperm count, total sperm count, sperm motility, morphology in the ejaculate, pregnancy rate, and hormonal profile. It identifies sperm density as the primary endpoint. The record does not report how hypotheses across these endpoints would have been prioritized or whether any adjustment for multiple testing was planned.
As a general statistical issue, testing multiple outcomes can increase the chance of finding an apparently unusual result even when no underlying effect exists. An analysis plan can address this by defining a primary hypothesis, specifying an order for secondary tests, or adjusting inference across a family of comparisons. The registry record does not report such a strategy, so the intended interpretation of any set of outcome tests is not specified.
Missing-data procedures and analysis populations are also not reported. The primary-outcome description states that data were not collected on the 2 participants and that the study terminated before results could be analyzed. This leaves no outcome dataset on which to evaluate missingness or compare analysis populations. The record does not specify an intention-to-treat or per-protocol analysis, nor a method for handling missing measurements. No conclusions about completed analyses can be drawn from the listed outcome plan.
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 |
|---|---|---|---|
| Ramipril | 0 | 1 | 0.0% |
| Placebo | 0 | 1 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Ramipril | 0 of 1 |
| Placebo | 0 of 1 |
The registry records 0 serious adverse events among 1 participant at risk in the ramipril arm and 0 among 1 participant at risk in the placebo arm. It also records 0 other adverse events among 1 participant at risk in each arm. No serious adverse-event terms are listed. Death counts are not reported in the registry record.
These entries should be read as recorded counts with small reported groups, not as proof that either intervention is free of adverse effects. The figures do not estimate how common an event would be in a larger population, and they do not establish a comparative safety difference. No rate needs to be calculated to see the central limitation: the record reports only 1 participant at risk in each arm.
The registry also says the trial terminated before outcome data could be collected and analyzed. The adverse-event fields are still registry entries, but they do not provide detailed descriptions, timing, severity beyond the serious-versus-other categories, or a basis for broader safety conclusions. No medical conclusion about ramipril or placebo follows from these counts alone.
12. What the Result Does, and Does Not, Mean
The record documents an intended randomized comparison of ramipril with placebo for sperm density in men with documented oligospermia. It also records the planned treatment schedules, a 32-week primary-outcome timeframe, and several secondary outcome areas. These registry entries describe the study question and design; they are not results.
The trial enrolled 2 participants and was terminated. The registry explanation states that data were not collected on those participants after the principal investigator moved to a different practice, and that the study ended before any results could be analyzed. As a result, there is no reported estimate of the effect of ramipril on sperm density, no uncertainty interval, and no statistical test of the planned comparison.
This lack of results does not show that ramipril changed sperm density, and it does not show that ramipril had no effect. It means that the registry record does not contain analyzed outcome evidence to answer the clinical question. The same limitation applies to listed secondary outcomes, including sperm measures, pregnancy rate, and hormonal profile.
The adverse-event entries report zero serious and zero other events among one participant at risk in each arm. Those small counts should not be generalized into a claim about safety. They describe what is recorded for this trial, while leaving substantial uncertainty about events beyond the recorded participants.
Likewise, planning assumptions or sample-size illustrations cannot replace observations. They may describe hypothetical requirements under specified statistical assumptions, but they do not represent observed power, an effect estimate, or proof that a treatment difference exists. The meaningful conclusion is narrow: this registry record documents a planned study that ended before the planned outcome comparison could be made.
13. Why This Trial Matters Statistically
This trial is statistically notable because it illustrates the difference between a registered design and an analyzed clinical comparison. Randomization, masking, a defined endpoint, and a planned timeframe describe how investigators intended to structure the study. They do not themselves generate evidence about a treatment effect. That requires collected outcome data and an analysis.
Enrollment was 2, and the registry states that data were not collected on those participants before termination. The absence of an estimate is more fundamental than imprecision around an estimate: there is no reported primary-outcome contrast to quantify. A confidence interval or p-value cannot repair the lack of measured outcomes, and a planning illustration cannot stand in for the missing comparison.
The record also shows why registered outcome lists and results must be distinguished. Sperm density is identified as the primary endpoint, and several sperm-related, pregnancy, and hormonal outcomes are listed. Without analyzed results, the presence of those outcomes in the record does not establish that they were measured or that any result favored either arm.
Finally, the limited adverse-event counts demonstrate the need to read denominators alongside event counts. Zero recorded events among one participant at risk in each arm offers little basis for generalizing safety. Taken together, the record is useful for understanding the intended design and the reason no results are available, but it cannot resolve the planned clinical question.
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 important limitation is that the registry reports no collected data for the 2 participants and no analyzed results before the study terminated. There is consequently no primary-outcome estimate and no secondary-outcome analysis. The stated reason for termination is that the principal investigator moved to a different practice.
The record does not report the unit or measurement procedure for sperm density, the planned statistical model, the treatment-effect summary, or the method for estimating uncertainty. It also does not describe baseline values, participant-level allocation, the allocation ratio, analysis populations, missing-data procedures, or a multiplicity strategy. These gaps prevent a detailed assessment of the intended analysis even apart from the absence of data.
A design-specific sample-size justification is not reported. Any effect-based planning illustration should not be confused with observed power or with an estimate from this study. The record does not explain how an observed effect used in planning could be reconciled with its statement that no participant data were collected.
The safety fields report 0 serious and 0 other events among 1 participant at risk in each arm, with deaths not reported in the registry record. Such limited entries cannot support broad safety conclusions. Overall, the registered information permits description of the intended trial and its termination, but not estimation of efficacy or a robust comparison of harms.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Ramipril for the Treatment of Oligospermia — NCT01856361.
- Registry record last updated 2017-06-02; status last verified 2017-04.
- Results first posted 2017-06-02.
- 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
NCT01856361 is a randomized, quadruple-masked, parallel-group trial sponsored by Weill Medical College of Cornell University. It planned to compare ramipril with placebo for sperm density in infertile men with documented oligospermia. The primary endpoint timeframe was 32 weeks; listed secondary outcomes included sperm measures, pregnancy rate, and hormonal profile.
The record lists enrollment of 2, a start date of 2013-07, primary completion in 2016-06, and status TERMINATED. It states that data were not collected on the 2 participants because the principal investigator moved to a different practice and the study ended before results could be analyzed. No treatment-effect analysis is reported. The adverse-event fields record zero serious and zero other events among one participant at risk in each arm; deaths are not reported in the registry record.