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 Gomco Versus Mogen: Which is Best? A Randomized Controlled Trial (NCT01726036), a randomized na study. The primary outcome is Neonatal Salivary Cortisol Level.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01726036 |
| Phase | NA |
| Condition | Circumcision, Male |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 274 |
| Arms in the primary outcome | n/a |
| Lead sponsor | TriHealth Inc. |
| Results posted | Yes |
2. Clinical Question
Population
The population of interest is neonates undergoing circumcision. The registry record identifies the condition as male circumcision and describes both interventions as clamps used for neonatal circumcision. It does not give further eligibility criteria or a detailed description of the analyzed population, so characteristics such as age limits, clinical setting, and exclusions are not reported in the registry record.
Intervention
The intervention is circumcision using the Gomco Circumcision Clamp. The registry describes this device as being used for neonatal circumcision. It does not report procedural details beyond the named clamp, so the specific technique, operator instructions, or other aspects of care are not reported in the registry record.
Comparator
The comparator is circumcision using the Mogen Circumcision Clamp, also described as a device used for neonatal circumcision. The study is a randomized comparison of the two clamps, but the registry record does not state the allocation ratio or describe how randomization was implemented.
Primary question
The primary question is whether neonatal salivary cortisol, used as an indicator of pain, differs in relation to the two clamp procedures. The stated assessment concerns levels before and after the procedure, approximately 2 hours before and 15 minutes after it. Although the endpoint description refers to change, the registry record does not report a numerical comparison of the change between groups or a statistical test addressing that question.
3. Trial Design
The registry identifies this study as a randomized, parallel-group trial comparing two devices: the Gomco Circumcision Clamp and the Mogen Circumcision Clamp. The study title describes it as a randomized controlled trial. The record lists single masking, but does not identify who was masked or explain how masking was maintained. It also does not describe the randomization sequence, allocation concealment, or the planned balance between groups.
The recorded enrollment is 274. That figure describes enrollment, not necessarily the number included in the primary-outcome analysis. The registry record does not give the analyzed sample size for the cortisol endpoint, reasons for exclusion from analysis, or group-specific numbers contributing pre-procedure and post-procedure measurements. The adverse-event record gives separate at-risk counts for the two groups, but those figures do not establish how many participants contributed to the primary analysis.
The study concerns male circumcision, and the intervention descriptions specify neonatal circumcision. The primary outcome is neonatal salivary cortisol, with measurement described approximately 2 hours before and 15 minutes after the procedure. The study is marked completed. Its recorded start is 2012-10 and its primary completion is 2014-03. The phase is listed as NA.
The registry record does not report a protocol-level explanation of the sample-size choice, the intended analysis population, or the statistical plan. It also does not specify whether other aspects of peri-procedural care were standardized. Those omissions limit how fully the conduct and analysis can be reconstructed from the registry record. Randomization is relevant to the intended comparison, but the available record alone does not establish that the groups were comparable in every respect or that all randomized participants were analyzed.
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 | Gomco Circumcision Clamp | Mogen Circumcision Clamp |
|---|---|---|
| STARTED | 137 | 137 |
| COMPLETED | 121 | 130 |
| NOT COMPLETED | 16 | 7 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
Population: Male infants receiving circumcisions
| Characteristic | Unit | Gomco Circumcision Clamp | Mogen Circumcision Clamp | Total |
|---|---|---|---|---|
| Participants analysed | 137 | 137 | 274 | |
| Age, Customized: Gestational Age | Weeks | 39.44 (SD 1.08) | 39.29 (SD 1.14) | 39.36 (SD 1.11) |
| Sex: Female, Male: Female | Participants | 0 | 0 | 0 |
| Sex: Female, Male: Male | Participants | 137 | 137 | 274 |
6. Primary Endpoint
The registry lists the primary outcome as Neonatal Salivary Cortisol Level, measured over Approximately 2 hours before and 15 minutes after the procedure.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | mcg/dL |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is titled Neonatal Salivary Cortisol Level and is measured in mcg/dL. The outcome description says pain will be assessed by change in salivary cortisol, with measurements before and after the procedure. The stated timeframe is approximately 2 hours before and 15 minutes after the procedure. The measure is a continuous outcome summarized using a mean and standard deviation.
In general, a before-and-after measure can describe how a biomarker changes over time around an event. Comparing changes between randomized groups can address whether the measured change differs between the assigned procedures, subject to the analysis plan and the completeness and quality of the measurements. A mean describes the central level of a continuous measure, while a standard deviation describes how spread out individual measurements are around that mean. Neither summary alone conveys the uncertainty in a group comparison.
The registry record does not report the cortisol values, group means, standard deviations, mean changes, or an estimated between-group contrast. It therefore does not establish the direction, size, or precision of any difference in this endpoint. The record also does not explain how a change was calculated, how missing pre- or post-procedure measurements were handled, or which statistical test was used.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies neonatal salivary cortisol as the primary outcome and describes an assessment before and after circumcision. However, it does not report numerical cortisol results or a single comparison between the Gomco and Mogen groups. The posted results therefore do not allow readers to determine the estimated difference in change, its direction, or its magnitude. No conclusion about which clamp had a higher or lower cortisol response can be drawn from the registry record.
The record notes that the primary outcome has several categories or time points and was not reduced to one comparison. That limitation matters for interpretation: a before-and-after endpoint can be represented in different ways, such as by comparing changes or by modeling measurements over time. Without a reported contrast and analysis method, the statistical question that was actually tested is not clear. The record also does not provide a confidence interval or p-value for the primary comparison.
In general, an estimate describes the observed difference under a specified analysis, while a confidence interval conveys how uncertain that estimate is under the model used. A narrow interval would indicate greater precision than a wide interval, but precision is not the same as clinical importance. A p-value, when reported, addresses compatibility with a specified null model; it does not measure the size or importance of an effect. None of these measures can be interpreted for the primary comparison because they are not reported in the registry record.
Enrollment was 274, but the registry record does not state how many participants contributed usable cortisol measurements or how many were included in the analysis. The adverse-event at-risk counts are 99 for Gomco and 117 for Mogen, but those counts are not identified as the primary-outcome analysis populations. They should not be used to infer the number analyzed for cortisol.
The study is randomized, which is a design feature intended to support a fair comparison of assigned groups. Nevertheless, the record does not provide enough details about allocation procedures, masking, follow-up, missing measurements, or analysis to evaluate how these features affected the outcome comparison. The listed record supports describing the trial question and design, but it does not support a statistical conclusion about the primary endpoint.
9. Statistical Methods Explained
What does a randomized parallel-group design mean?
In general, randomization assigns participants to study groups using a chance-based process. Its purpose is to reduce systematic differences between groups at the point of assignment, including differences that may not be measured. A parallel-group design means participants are assigned to one group and evaluated in that group rather than switching between the study procedures. The registry identifies this study as randomized and parallel, with Gomco and Mogen clamp groups. It does not report the sequence-generation method, allocation concealment, or allocation ratio. Those details are not reported in the registry record, so the randomization process cannot be fully evaluated from the record.
What does single masking tell readers?
The record labels masking as single. In general, masking can reduce the influence of expectations on treatment delivery, measurement, or reporting. The term alone does not say who was masked. The registry record does not identify the masked participants or personnel, describe how masking was maintained, or explain whether masking was feasible during the procedure. It is therefore not possible to determine from the record which parts of the study may have been protected from knowledge of group assignment.
How should a continuous outcome be understood?
Salivary cortisol is recorded as a continuous measure in mcg/dL, and the listed summary type is the mean with standard deviation. In general, a mean combines the individual values into a measure of central tendency. The standard deviation describes the spread of those values, not the uncertainty of the mean or of a group difference. A statistical comparison of group means generally needs an estimated contrast and a measure of its uncertainty. The registry record does not report those quantities for the primary endpoint.
The endpoint description refers to change between a pre-procedure and a post-procedure measurement. In general, a change score is calculated from paired measurements on the same participant. An alternative approach may model the post-procedure value while accounting for the pre-procedure value, or model measurements at both times. These approaches can target related but not identical quantities and rely on different modeling choices. The registry record does not report which approach was used, how the change was defined, or whether baseline cortisol was included in an adjusted analysis.
Why do the analysis details matter?
In general, an analysis plan specifies the outcome definition, comparison, statistical model, handling of missing data, and population to be analyzed. These decisions determine what the resulting estimate means. The record lists one analysis, but does not describe its model or test. It also does not report whether the analysis followed randomized assignment, used only participants with complete measurements, or applied another rule. Without those details and the numerical result, the analysis cannot be independently interpreted or checked against the stated endpoint.
A confidence interval, if reported, would describe uncertainty around an estimated contrast under the assumptions of the analysis. Its width is affected by the amount of information in the data and by variation in the outcome. In general, a point estimate without an interval gives an incomplete account of precision, while a p-value without an effect estimate does not show the size of the observed difference. Neither an interval nor a p-value for the primary comparison is reported in the registry record.
What can sample-size planning illustrations show?
In general, a planning calculation asks how many participants might be needed to detect a specified effect under stated assumptions. The registry description of its planning illustrations refers to a two-sided significance level of 0.05, equal allocation, a normal approximation, and effects expressed as fractions of an observed effect. Such illustrations are not the same as the trial’s own design justification, and they are not observed power. The registry record does not report the protocol’s sample-size justification or the assumptions used by investigators when planning enrollment.
A planning estimate depends on assumptions about the effect to detect, outcome variability, allocation, and statistical method. If assumptions do not match the actual study, the resulting illustration may not describe the trial’s achieved precision. The record does not report a numerical cortisol effect estimate from which readers could assess such assumptions, nor does it provide a primary-outcome analysis to connect planning with observed results. Any planning illustration should therefore be understood as conditional on its stated assumptions, not as evidence that the trial detected or failed to detect a difference.
Why does variability matter?
In general, greater variability in a continuous outcome makes it harder to distinguish a group difference from random variation, all else being equal. The standard deviation is one way to describe variability in the individual measurements. When outcome data are strongly skewed or contain influential extreme values, a mean-based summary or a normal approximation may not adequately describe the data. The registry record does not report the cortisol distribution or diagnostics, so the suitability of any particular model cannot be assessed.
10. Multiplicity, Missing Data and Analysis Populations
The registry record lists two outcome measures and one analysis, but does not describe the full set of outcomes, how they were prioritized, or whether any statistical adjustment was used for multiple testing. The primary outcome is identified as neonatal salivary cortisol, yet its description refers to measurements at more than one time point and the record notes that the outcome was not reduced to one comparison. The registry record does not explain how those time points or categories were handled in analysis.
In general, multiplicity arises when several outcomes, time points, or comparisons are examined. If a study tests multiple hypotheses, the chance of at least one apparently unusual result can increase unless the analysis plan addresses that issue. An adjustment or a prespecified hierarchy can help define how results should be interpreted. No such strategy is reported in the registry record, so it is not possible to establish whether multiplicity was considered in the analysis.
The record does not report the number of participants with complete pre- and post-procedure cortisol measurements, the amount or pattern of missing data, or the method used to handle missing observations. These details matter because an analysis limited to participants with complete measurements may differ from an analysis that uses other approaches, especially if missingness is related to participant characteristics or outcomes. No analysis population, such as all randomized participants or a subset meeting specified criteria, is described for the primary endpoint. The registry record therefore does not allow readers to determine how missing data or analysis-population choices may have affected the result.
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 |
|---|---|---|---|
| Gomco Circumcision Clamp | 0 | 99 | 0.0% |
| Mogen Circumcision Clamp | 0 | 117 | 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 |
|---|---|
| Gomco Circumcision Clamp | 0 of 99 |
| Mogen Circumcision Clamp | 2 of 117 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Gomco Circumcision Clamp | Mogen Circumcision Clamp |
|---|---|---|---|
| Adhesion at 2 months | Surgical and medical procedures | 0 of 99 | 1 of 117 |
| Pustule at head of penis - self resolved | Surgical and medical procedures | 0 of 99 | 1 of 117 |
The adverse-event record lists serious adverse events for the Gomco group as 0 among 99 participants at risk and for the Mogen group as 0 among 117 participants at risk. These are the serious-event counts and denominators recorded for the groups. The record lists no top serious-event terms. Death counts are not reported in the registry record.
For other adverse events, the record lists 0 among 99 participants at risk in the Gomco group and 2 among 117 participants at risk in the Mogen group. These counts describe the posted adverse-event entries; the record does not provide event descriptions or explain how events were collected, classified, or attributed. It also does not report the timing, duration, or severity of the other adverse events.
In general, a zero recorded count means no events of that category are listed for the stated group in the record. It does not, by itself, establish that no event could occur or explain the completeness of surveillance. The at-risk denominators are not identified as the primary-outcome analysis populations. These safety entries should be read separately from the cortisol endpoint and do not establish a comparative effect on neonatal pain.
12. What the Result Does, and Does Not, Mean
The registry record describes a randomized, parallel-group comparison of Gomco and Mogen circumcision clamps in a study focused on neonatal pain. It identifies salivary cortisol, measured before and after the procedure, as the primary outcome. This establishes the intended topic of the trial, but the record does not provide the numerical primary-outcome results needed to assess the observed comparison.
The result does not establish whether the mean cortisol change differed between the groups, how large any difference was, or how precisely it was estimated. The record does not provide group values, an effect estimate, a confidence interval, or a p-value for a single primary comparison. It is therefore not possible to characterize the primary finding as favoring either group, as statistically distinguishable, or as similar on the basis of the posted results.
In general, absence of a reported estimate is not evidence that the groups had identical outcomes. It also does not establish that a difference exists. Those interpretations require results that are not reported in the registry record. A comparison of observed averages, even if available, would need to be considered alongside its uncertainty, the endpoint definition, and the analysis population.
The adverse-event entries describe recorded counts in the stated groups, but they do not substitute for the primary endpoint. They also do not provide enough detail to characterize the nature or clinical context of the other adverse events. The safety record should not be used to draw a conclusion about the comparative cortisol response.
Overall, the study design and stated outcome define a clinically relevant statistical question, while the posted results do not provide the primary comparison required to answer it. Readers can identify what was intended to be measured and how the groups were organized, but cannot infer the direction, magnitude, or precision of the primary outcome from the registry record.
13. Why This Trial Matters Statistically
This trial matters statistically because it illustrates the distinction between a clear study question and a reportable answer to that question. The registry identifies two randomized groups and names a continuous primary outcome, but does not report a numerical between-group comparison. Without an estimate and its uncertainty, readers cannot assess the direction or precision of the result, regardless of how clearly the question is framed.
The endpoint also involves measurement before and after a procedure. In general, repeated measurements require a defined comparison: the analysis might focus on change, adjust for the pre-procedure value, or model measurements over time. These choices determine the estimand, meaning the specific quantity the analysis is intended to estimate. The record describes change but does not report the calculation or analysis used, and notes that the outcome was not reduced to one comparison.
The study further highlights the difference between enrollment and the analysis population. Enrollment is recorded as 274, while the number contributing the primary endpoint is not reported in the registry record. Without analyzed counts and information on missing measurements, the relationship between enrollment and the precision of the primary comparison cannot be assessed.
Finally, the safety counts are separate from the primary outcome, and the registry record does not describe the statistical approach to multiple outcomes or time points. These reporting gaps do not invalidate the study design, but they restrict what can be concluded from the posted record. A statistical interpretation depends not only on design labels and endpoint names, but also on a defined analysis and results that show both effect size and uncertainty.
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 trial-specific limitation for interpretation is that the registry record does not report numerical results for the primary cortisol endpoint. It does not provide pre-procedure or post-procedure values, group means, standard deviations, changes, or a between-group estimate. The direction and size of any observed difference are therefore unknown from the posted results.
The endpoint description refers to change, but the record also indicates that the primary outcome has several categories or time points and was not reduced to one comparison. The analysis method and the specific contrast are not reported. Without that information, readers cannot determine which statistical quantity would answer the stated question or whether the analysis matches the endpoint description.
The registry record does not report group-specific primary-outcome analysis counts, missing-measurement amounts, or the analysis population. The recorded enrollment of 274 should not be treated as the number analyzed for cortisol. Although the adverse-event record includes at-risk denominators, it does not identify them as the cortisol analysis populations.
Further limitations of the available record include the absence of details about randomization procedures, allocation concealment, who was masked, and how masking was maintained. The record does not report a protocol-level sample-size justification, a detailed statistical analysis plan, a multiplicity strategy, or the handling of missing data. These items are not reported in the registry record, so their impact cannot be evaluated.
The adverse-event entries provide counts but limited context. Event descriptions and death counts are not reported in the registry record. These constraints apply to interpretation of the posted record and do not establish what may have been described in other study materials.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Gomco Versus Mogen: Which is Best? A Randomized Controlled Trial — NCT01726036.
- Registry record last updated 2019-06-05; status last verified 2018-01.
- Results first posted 2019-05-16.
- 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 NCT01726036, titled “Gomco Versus Mogen: Which is Best? A Randomized Controlled Trial.” It identifies TriHealth Inc. as the sponsor and records the study as completed. The study is randomized, single-masked, and parallel, with enrollment of 274. The listed interventions are the Gomco Circumcision Clamp and the Mogen Circumcision Clamp.
The primary outcome is neonatal salivary cortisol level in mcg/dL, described as a mean with standard deviation and measured approximately 2 hours before and 15 minutes after the procedure. The stated purpose is to compare the clamps in relation to neonatal pain. A numerical primary-outcome comparison, its uncertainty, and details of the analysis population are not reported in the registry record.
The adverse-event record lists no serious events in either group, with at-risk counts of 99 for Gomco and 117 for Mogen. It lists other adverse events for the groups as 0 and 2, respectively. Death counts are not reported in the registry record.