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 Superior Hypogastric Blockade for Postoperative Pain (NCT03428152), a registered phase not stated study. The primary outcome is Postoperative Pain Scores.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03428152 |
| Phase | Phase not stated |
| Condition | Superior Hypogastric Plexus Block, Hysterectomy, Pain, Postoperative |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 78 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Derince Training and Research Hospital |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing hysterectomy for gynecologic disease are the clinical population described. The primary outcome population is listed as 37 patients with a superior hypogastric block, with 7 excluded, and 41 patients without the block, with 11 excluded. The registry record does not report further eligibility criteria, reasons for exclusion, or patient characteristics.
Intervention
The intervention is a superior hypogastric block performed during pelvic surgery. The study rationale describes the block as a possible approach to postoperative visceral pelvic pain and proposes assessing pain scores and opioid consumption. The registry record does not provide procedural details beyond naming the block.
Comparator
The comparison group is described as patients without a superior hypogastric block. This group could include patients with an epidural catheter, patients receiving another block technique such as a TAP block, or patients considered unsuitable for the superior hypogastric block. The record therefore does not describe a uniform, like-for-like control intervention.
Primary question
The primary question is whether postoperative pain scores differ between patients with and without a superior hypogastric block during the postoperative 48 hour follow-up. Pain is measured using a Visual Analogue Scale (VAS) at PACU and specified ward time points. The registry record does not report numerical group results, an estimated comparison, or a statistical test answering this question.
3. Trial Design
This completed study concerns superior hypogastric block during hysterectomy surgery and postoperative pain. Derince Training and Research Hospital is identified as the sponsor. The recorded study start is 2018-02-09, and primary completion is recorded as 2018-07-23. The registry status is COMPLETED. These administrative details establish the study’s recorded timeline and status, but do not establish that outcome results were posted.
The intervention arm is described as participants with a superior hypogastric block. The comparison arm includes participants without that block. The registry description says that this group may include patients with an epidural catheter, patients receiving another block technique, or patients unsuitable for superior hypogastric block, including when the surgeon opens the retro-peritoneum intraoperatively. These are clinically different circumstances, so the arms are not described as a uniform treatment-versus-control comparison.
Allocation is not stated, and the registry record specifically flags that this is not a randomized comparison. Without random allocation, differences between groups may reflect characteristics or clinical circumstances that also influence pain and postoperative care. The record does not report whether or how those factors were measured or adjusted for. The study should therefore be read as a comparison between the recorded groups, not as a randomized estimate of the block’s effect.
The primary outcome is described as mean postoperative VAS pain scores during follow-up in PACU and on the ward. Listed assessment times include PACU and postoperative 1st, 6th, 12th, 24th, and 48th hours. The registry also lists secondary outcomes concerning rescue analgesic time, operation duration, hospital stay, and complications due to the block. Numerical results and detailed analysis procedures for these outcomes are not reported in the registry record.
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 | Hypo | NoHypo |
|---|---|---|
| STARTED | 37 | 41 |
| COMPLETED | 30 | 30 |
| NOT COMPLETED | 7 | 11 |
Reasons for not completing this period:
| Reason | Hypo | NoHypo |
|---|---|---|
| Physician Decision | 4 | 2 |
| Protocol Violation | 3 | 5 |
| Lack of Efficacy | 0 | 4 |
Analysis population for the primary outcome, as defined in the registry: 37 patients with a superior hypogastric block (7 was excluded); 41 patients without a superior hypogastric block (11 was excluded).
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 | Hypo | NoHypo | Total |
|---|---|---|---|---|
| Participants analysed | 37 | 41 | 78 | |
| Age, Continuous | years | 52.36 (SD 6.51) | 51.63 (SD 7.49) | 52 (SD 6.96) |
| Sex: Female, Male: Female | Participants | 37 | 41 | 78 |
| Sex: Female, Male: Male | Participants | 0 | 0 | 0 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: Turkey | Participants | 37 | 41 | 78 |
6. Primary Endpoint
The registry lists the primary outcome as Postoperative Pain Scores, measured over postoperative 48 hour follow-up (PACU and ward).
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Standard Deviation |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is postoperative pain measured with a 10 cm Visual Analogue Scale. The description specifies a score from 0-10, where 0 means no pain and 10 means the worst pain ever. Scores are planned for PACU and at postoperative 1st, 6th, 12th, 24th, and 48th hours on the ward. The registry identifies the outcome as a mean with standard deviation, a common way to describe the central level and spread of a continuous measurement.
Pain scores are used because pain is a patient-relevant symptom that can be recorded repeatedly after surgery. Repeated measurements can describe how reported pain varies over the postoperative period rather than relying on a single assessment. However, measurements at different times are related: scores from the same patient are not independent observations. A sound analysis would need to account for that relationship if it compared patterns over time. The registry record does not report the analysis approach.
The endpoint definition does not itself establish a difference between groups. A numerical comparison, its uncertainty, and the method used to handle repeated scores would be needed to interpret the observed pattern. Those results are not reported in the registry record. The registry’s stated primary outcome population includes 37 patients with the block, with 7 excluded, and 41 without the block, with 11 excluded; reasons for exclusion and the handling of unavailable scores are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a clinical question and a primary pain outcome, but it does not provide the numerical pain-score results. There is no posted mean or standard deviation for either group, no reported difference between groups, and no confidence interval or p-value. The direction, magnitude, and precision of any observed difference therefore cannot be assessed from the registry record. A conclusion about whether the groups had similar or different pain scores would go beyond what is reported.
The study compares patients with a superior hypogastric block with patients without that block. Allocation is not stated, and the record identifies the comparison as nonrandomized. The no-block group may include patients receiving other forms of care or those considered unsuitable for the block. Consequently, even if group results were available, a raw difference could reflect differences in patient circumstances, clinical decisions, or co-interventions as well as any association with the block. The registry record does not describe adjustment for such factors.
The listed primary outcome covers repeated pain assessments in PACU and on the ward through postoperative 48 hour follow-up. A pattern across those times could convey information not captured by one average alone. But repeated measurements within a patient are correlated, and the analysis should account for that correlation. The record does not report whether the investigators used a repeated-measures model, separate comparisons at each time, or another approach. Nor does it report how missing measurements were handled.
The registry lists secondary outcomes, including rescue analgesic time, duration of operation, length of hospital stay, and complications due to the block. Numerical results for these outcomes are not reported in the registry record. The study summary also describes opioid consumption as part of the investigators’ theory, but a corresponding numerical result is not reported in the registry record. Thus, the posted information does not permit an assessment of these secondary outcomes or their uncertainty.
Completion status indicates the recorded study status, not that results are available or that the primary question has been resolved. The record’s outcome population lists 37 patients in the block group, with 7 excluded, and 41 in the group without the block, with 11 excluded. It does not state why these participants were excluded, whether exclusions occurred before or after outcome collection, or how the analysis population was defined. These omissions limit interpretation even before considering the absence of numerical results.
The most defensible reading is therefore descriptive: the registry specifies a nonrandomized group comparison and a repeated VAS outcome, but supplies no primary outcome estimate. Neither benefit nor lack of difference can be inferred from absent results. The record also does not establish that any observed association, if one were later reported, would be caused by the block.
9. Statistical Methods Explained
Statistical methods help translate observed measurements into estimates while accounting for variation and design. In this study, the registered primary measure is a continuous pain score summarized by a mean and standard deviation. The record does not report numerical scores or an analysis, so the concepts below explain how such data are generally interpreted rather than describing methods confirmed for this trial.
What does a mean and standard deviation describe?
For a continuous outcome, the mean is a measure of the center of the observed scores. The standard deviation describes how dispersed individual scores are around that mean. They answer different questions: the mean describes a group’s average level, while the standard deviation describes variability among observations. A mean alone does not show how precisely the group mean has been estimated. Precision depends in part on the amount of information and the variability in the data.
A mean difference between groups, if reported, would express the contrast in average scores on the VAS scale. Its interpretation would depend on the scale, the clinical context, the study design, and the uncertainty around the estimate. The registry record does not report such a contrast. No difference should be calculated from the outcome definition or participant counts.
What does a confidence interval add?
In general, a confidence interval gives a range of values compatible with the data under the stated statistical method. It conveys uncertainty about an estimate, rather than showing the full spread of individual patient outcomes. A narrow interval indicates greater precision than a wide interval, though precision does not by itself establish that a result is clinically important or free from bias. No confidence interval for the primary outcome is reported in the registry record.
A p-value, when used, summarizes how unusual the observed data would be under a specified null hypothesis and analysis assumptions. It does not give the probability that a treatment works, nor does it measure the size or importance of a difference. It should be read alongside the estimate, its interval, and the design. No p-value or tested hypothesis for the primary outcome is reported in the registry record.
Why do repeated pain measurements need care?
The registered assessments occur at PACU and at postoperative 1st, 6th, 12th, 24th, and 48th hours. Repeated scores from the same patient tend to be related because they come from the same person and postoperative course. Treating every score as if it came from a different person can make uncertainty estimates misleading. General approaches can model within-person correlation or summarize a prespecified aspect of the trajectory. The appropriate choice depends on the research question and data structure. The registry record does not state which approach was used or whether all scheduled measurements were analyzed together.
Analyzing each time point separately creates a further issue: multiple statistical tests increase the chance of at least one apparently notable result when no real difference exists. A prespecified primary time point, an overall repeated-measures test, or an adjustment for multiple comparisons can address this concern in different ways. The registry record does not report a multiplicity plan, analysis hierarchy, or results at individual time points. The timing schedule alone does not reveal how investigators handled multiple assessments.
Why can over-dispersion matter?
Over-dispersion is a general issue for count outcomes when observed variation exceeds what a chosen statistical model expects. It can lead to uncertainty estimates that are too small if ignored. This concept is relevant to some event-count analyses, but the primary outcome is a continuous VAS score, not a count. The registry record does not report a model for any secondary outcome that would allow a judgment about over-dispersion.
What changes in a nonrandomized comparison?
Randomization, when used, aims to make treatment groups comparable on average with respect to measured and unmeasured factors. This record does not report randomized allocation; allocation is not stated, and the comparison is described as nonrandomized. The no-block group can include patients with different procedures or clinical reasons for not receiving the block. Such differences may be related to postoperative pain and can complicate interpretation of a group contrast. Statistical adjustment can address measured differences under appropriate assumptions, but cannot guarantee removal of bias from unmeasured factors. The registry record does not report adjusted estimates, covariates, or an adjustment plan.
Observed group differences in a nonrandomized study are therefore associations unless the design and analysis support stronger causal interpretation. A statistical model cannot, by itself, turn a nonrandomized comparison into a randomized one. Understanding who entered each group, why, and how outcomes were measured is important alongside any model-based estimate.
What does the planning illustration represent?
The registry’s sample-size assumptions describe a planning illustration based on an observed effect, with a two-sided significance level of 0.05, equal allocation, and a normal approximation. The effect to detect is framed as a stated fraction of the observed effect. Such calculations are hypothetical planning scenarios, not observed trial outcomes and not observed power. The record does not report the calculated sample-size values in the registry record for this analysis, nor does it report the trial’s own design justification. The planning assumptions should not be mistaken for evidence about the precision or success of the actual study.
Overall, the statistical methods that would be useful for interpreting this endpoint include a clearly defined group contrast, uncertainty intervals, appropriate handling of repeated observations, transparent treatment of missing scores, and careful consideration of nonrandom allocation and multiplicity. These are general considerations. The registry record does not report enough analysis detail or numerical results to determine how they were addressed in this study.
10. Multiplicity, Missing Data and Analysis Populations
The primary outcome is measured repeatedly, with assessments listed for PACU and postoperative 1st, 6th, 12th, 24th, and 48th hours. Considering multiple time points raises a multiplicity question: testing each time separately can increase the chance of a seemingly unusual finding across the set of tests. An overall model or a prespecified primary time point can offer a different way to frame the question. The registry record does not report which approach was planned or used, whether any adjustment was made, or which outcome was treated as primary in the analysis.
The registry lists secondary outcomes concerning rescue analgesic time, operation duration, length of hospital stay, and complications due to the block. The study summary also mentions opioid consumption as an investigator interest. Considering multiple outcomes can create additional opportunities for selective emphasis unless analyses and interpretation are prespecified. The registry record does not report a multiplicity strategy or numerical results for the secondary outcomes.
Missing-data handling is also unclear. The primary outcome population is described as 37 patients with a block, with 7 excluded, and 41 without a block, with 11 excluded. The reasons for exclusion, timing of exclusion, availability of scores at each assessment, and statistical treatment of missing values are not reported in the registry record. It is therefore not possible to determine whether exclusions were related to outcomes or how they might affect interpretation.
The record does not state whether the primary analysis used all eligible participants, only participants with recorded scores, or another analysis population. A complete-case analysis and methods that use partial repeated measurements can rely on different assumptions. Without the analysis population and missing-data method, the reported participant descriptions do not establish which observations contributed to any outcome estimate. No numerical outcome analysis is reported in the registry record.
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 |
|---|---|---|---|
| Hypo | 0 | 37 | 0.0% |
| NoHypo | 0 | 41 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Hypo | 0 of 37 |
| NoHypo | 0 of 41 |
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 |
|---|---|
| Hypo | 0 of 37 |
| NoHypo | 0 of 41 |
The registry lists serious adverse events in the Hypo group for 37 participants at risk, with 0 affected, and in the NoHypo group for 41 participants at risk, with 0 affected. It also lists other adverse events for 37 participants at risk in Hypo, with 0 affected, and 41 participants at risk in NoHypo, with 0 affected. Deaths are listed as 0 in each group. These are the recorded figures, not proof that the risk of an event is absent.
A zero count means that no events of the specified category are recorded for the listed group in this registry entry. It does not establish that no event could occur, and it does not show how precisely the underlying risk is known. Rare events may not appear in a study record, particularly when the amount of observed information is limited. No confidence intervals for these safety counts are reported in the registry record.
The record’s secondary outcome list includes complications due to the superior hypogastric block. The posted adverse-event figures should be read in the context of the registry’s reporting, rather than as a complete description of every possible postoperative complication. Definitions, surveillance procedures, and the period over which adverse events were collected are not reported in the registry record. These counts do not support a broader safety conclusion.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a completed study examined superior hypogastric block during hysterectomy in relation to postoperative pain. It identifies a nonrandomized comparison, describes the group definitions, and specifies repeated VAS assessments through postoperative 48 hour follow-up. It also records adverse-event counts and lists several secondary outcomes. These details describe the research question and its planned measurement context.
The record does not report numerical primary pain scores, a difference between groups, a confidence interval, or a p-value. It therefore does not show the size or precision of any pain-score contrast. The absence of a reported result is not evidence that the groups were the same, and it is not evidence that the block reduced pain. No direction or magnitude can be inferred from the record.
The design also limits what an observed comparison could establish. Allocation is not stated, the comparison is identified as nonrandomized, and the group without the block may include patients receiving other techniques or those considered unsuitable for the block. These features create the possibility that the groups differ for reasons related to their clinical circumstances. The record does not report an adjustment strategy that would address such differences.
Even with a numerical difference, interpretation would require considering uncertainty, repeated measurements, missing scores, and multiplicity across assessments and outcomes. Those analysis details are not reported in the registry record. The adverse-event counts show zero recorded events in the listed categories for both groups, but do not establish absence of risk or comprehensive safety surveillance.
The appropriate conclusion is limited: the record documents a clinical question and its outcome definitions, but does not provide results needed to answer the primary question. It cannot establish either a treatment effect or a lack of effect. The listed sample-size assumptions are planning illustrations, not observed power and not a substitute for an outcome estimate with its uncertainty.
13. Why This Trial Matters Statistically
This trial is statistically notable because it links a clinically specific intervention with repeated measurement of postoperative pain. A pain trajectory can carry different information from a single score: measurements can reflect the course of recovery across PACU and the ward. At the same time, repeated scores from one patient are correlated, so the analysis must account for their dependence if it estimates an overall pattern or compares groups over time. The registry record defines the timing but does not report the analysis.
The comparison also illustrates why design matters as much as the choice of statistical test. The record describes no randomized allocation and identifies the comparison as nonrandomized. Patients without the block may have other procedures or clinical reasons for not receiving it. A difference between these groups, if reported, would need to be interpreted in light of that treatment selection and possible confounding; a model alone cannot guarantee a causal answer.
The registered endpoint is a mean of a continuous score, which invites attention to both the size of a group contrast and its precision. A point estimate without an uncertainty interval can be difficult to interpret, while a p-value alone does not communicate clinical magnitude. Yet no numerical estimate or uncertainty is reported in the registry record. The case demonstrates the distinction between registering an outcome and reporting evidence about that outcome.
Finally, zero adverse-event counts should be read as observed registry counts, not as proof of zero risk. Counts, follow-up, event definitions, and precision all matter in safety interpretation. Taken together, the record is useful for understanding the question and design constraints, while its absent outcome analysis prevents a statistical judgment about the primary endpoint.
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.
Several trial-specific limitations affect interpretation. First, allocation is not stated and the comparison is explicitly described as nonrandomized. The block and no-block groups may therefore differ in ways that influence pain outcomes. The no-block group is heterogeneous by description: it can include patients with an epidural catheter, patients receiving another block technique, or patients unsuitable for superior hypogastric block. This weakens a simple interpretation of the group contrast as the effect of one procedure versus no procedure.
Second, the primary outcome population lists 37 patients with the block, with 7 excluded, and 41 without the block, with 11 excluded. Reasons for these exclusions and their timing are not reported in the registry record. It is not possible to assess whether exclusions could have introduced selection bias or how the listed population relates to the enrolled participants.
Third, although the outcome is scheduled across PACU and several ward assessments through 48 hours, the record does not report numerical scores, whether all scheduled assessments were collected, or how missing measurements were handled. It also does not state whether the analysis accounted for correlation among repeated scores, or how multiplicity across time points and secondary outcomes was addressed.
Fourth, the record’s adverse-event counts do not include reported confidence intervals or details of event definitions and surveillance. The entries of zero recorded events cannot establish that no risk exists. The record also does not report results for its listed secondary outcomes or a numerical result for opioid consumption mentioned in the study summary.
Finally, the record does not report an analysis plan, covariate adjustment, or an outcome estimate. These gaps prevent assessment of both the size and precision of any group difference. The completed status alone does not resolve these limitations.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Superior Hypogastric Blockade for Postoperative Pain — NCT03428152.
- Registry record last updated 2024-03-13; status last verified 2024-02.
- Results first posted 2019-06-03.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record describes a completed study of superior hypogastric block during hysterectomy, sponsored by Derince Training and Research Hospital. The recorded start date is 2018-02-09, and primary completion is 2018-07-23. The primary outcome is mean VAS pain score during postoperative 48 hour follow-up, with assessments in PACU and at specified ward times.
The comparison is nonrandomized, and allocation is not stated. The group without the block may include patients receiving other techniques or patients unsuitable for the block. The outcome population is listed as 37 with the block, with 7 excluded, and 41 without the block, with 11 excluded. Reasons for exclusion are not reported in the registry record.
Although the record lists secondary outcomes and adverse-event counts, numerical primary outcome results, uncertainty estimates, and an analysis are not reported in the registry record. The reported adverse-event entries list zero serious and other events, and zero deaths in both groups; these counts do not establish absence of risk. Overall, the registry defines the question and study context but does not provide results that answer the primary question.