Temporary Aortic Occlusion With the Abdominal Tourniquet for Refractory Postpartum Haemorrhage: A Proof-of-Concept Study in a War-Affected Region: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Temporary Aortic Occlusion With the Abdominal Tourniquet for Refractory Postpartum Haemorrhage: A Proof-of-Concept Study in a War-Affected Region (NCT07016568), a na na study. The primary outcome is Time to Bleeding Control After AAJT-S Device Application.

2. Clinical Question

This is a proof-of-concept question about immediate bleeding control in the described clinical setting. It is not a comparative question about whether the device performs better than another treatment, because the registry record identifies a single group and no control arm. The record also describes hemodynamic stabilization time and long-term maternal recovery status as secondary outcomes. Numerical results for these secondary outcomes are not reported in the registry record. The primary question is therefore clear from the stated endpoint and study purpose, but the posted information does not establish how often bleeding was controlled or how long control took.

3. Trial Design

The registry record describes a completed, single-group device study with enrollment of 4. Its title identifies it as a proof-of-concept study in a war-affected region. LLC UkrMedGroup is listed as the sponsor. The recorded start date is 2024-12-01, and the recorded primary completion date is 2025-04-15. The phase is listed as NA.

The listed arm is the AAJT-S Device Intervention Arm. Participants are described as receiving standard postpartum haemorrhage management, followed by AAJT-S application if bleeding remains uncontrolled after uterotonics and uterine balloon tamponade. The arm description is incomplete in the registry record, so details beyond that sequence are not reported. The stated purpose is to assess whether the device can temporarily control severe bleeding while clinicians prepare surgery or other definitive treatment.

Allocation is listed as NA, masking as NONE, and the model as SINGLE GROUP. These design features mean the record does not describe random assignment, masking, or a concurrent control group. Consequently, the study is suited to describing observations after device use, but its design does not provide a direct comparison with another intervention or with an untreated group. It also cannot separate the device’s contribution from other care delivered around the same time.

The registry record lists five outcome measures, including the primary time-to-bleeding-control measure and the named secondary outcomes of hemodynamic stabilization time and long-term maternal recovery status. It lists no analyses. Detailed eligibility criteria, the full device procedure, follow-up schedule, and additional protocol details are not reported in the registry record. The available design information should therefore be read as a high-level description rather than a complete account of how the study was conducted.

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.

Before assignment: All enrolled participants (N=4) met the eligibility criteria and were assigned to the intervention arm. No screening failures, exclusions, or withdrawals occurred prior to device application.

Overall Study

5. Baseline Characteristics

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

6. Primary Endpoint

The registry lists the primary outcome as Time to Bleeding Control After AAJT-S Device Application, measured over Within 10 minutes of AAJT-S device application.

The primary endpoint is time to bleeding control after AAJT-S application, measured in minutes. It is defined as the interval from inflation of the device to visible cessation of external vaginal bleeding in patients with severe postpartum haemorrhage due to uterine atony. The attending provider determines bleeding control by visual clinical assessment. The stated timeframe is within 10 minutes of device application.

This endpoint focuses on an immediate clinical event rather than a later recovery outcome. The study description gives a specific reason for measuring it: temporary control could provide time to prepare for definitive surgical management or transfusion. Measuring elapsed time also captures how quickly bleeding control is observed, not merely whether control is recorded at some later point. That rationale comes from the endpoint description; it does not establish that the intended clinical benefit occurred.

The registry record specifies the mean and standard deviation as the summary format for this continuous measure. The mean describes the average observed time, while the standard deviation describes variation in times among participants. However, the actual mean, standard deviation, and participant-level observations are not reported in the registry record. The endpoint definition alone therefore does not show the observed time to control, the range of observed experience, or how consistently the event occurred. The posted information also does not report a numerical estimate of how many participants achieved bleeding control within the stated timeframe.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The primary endpoint is continuous: it measures elapsed time in minutes. The registry record specifies that the intended summary is a mean with a standard deviation. A mean is a measure of the center of a set of observations, while a standard deviation describes how spread out those observations are around the mean. Together, these summaries can describe average timing and variation, but only when the underlying outcome values and the number of observations contributing to them are available. The registry record does not report the primary mean, standard deviation, or analysis population.

A mean can be sensitive to unusually long or short observations, particularly when the number of observations is limited. The standard deviation helps describe variation, but it does not show the full shape of the data. For an endpoint such as time to visible bleeding cessation, additional information about individual values, skewness, or the proportion with an observed event could help readers understand the pattern. Such information is not reported in the registry record. This is a general statistical consideration, not a claim about the distribution in this study.

In general, a confidence interval expresses uncertainty around an estimate by giving a range of values compatible with the data and the method used. A point estimate without an interval can conceal substantial uncertainty, while an interval can show whether the estimate is precise or imprecise. No confidence interval for the primary endpoint is reported in the registry record. Without an estimate and its uncertainty, readers cannot judge the precision of the average time from the posted results.

A p-value, when used, quantifies how compatible data are with a specified statistical model or null hypothesis. It does not measure the probability that a treatment works, nor does it measure clinical importance. The registry record lists no analyses and reports no p-value for the primary endpoint. The planned statistical test, null hypothesis, and any adjustment for the outcome structure are not reported in the registry record. It would therefore be inappropriate to infer that a particular test was performed or that a particular threshold determined the study’s conclusions.

The study model is single-group, and allocation is listed as NA. Those features matter to interpretation: statistical summaries within the group would describe the observed participants, but would not estimate a contrast with a separate control group. A within-group endpoint summary cannot by itself distinguish the effect of device application from the effects of accompanying care, timing, or other clinical circumstances. No comparative estimate is reported in the registry record.

The registry record also includes assumptions for a sample-size planning illustration: a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect defined as a stated fraction of the observed effect. It specifies that time-to-event illustrations use total events under the Schoenfeld method and other illustrations use participants per arm. These assumptions describe a planning illustration, not the actual single-group study design. No numerical planning estimates or observed-effect value are reported in the registry record. A planning illustration is not evidence of an observed result and is not observed power.

The illustration’s equal-allocation assumption describes two arms, whereas the study design is listed as single-group. This distinction prevents confusing an illustrative planning scenario with the participants or allocation actually recorded for this trial. Sample-size calculations depend on assumptions about the effect to detect and the statistical method. If those assumptions differ from the actual question or design, the illustration should not be interpreted as a feature of the trial’s conduct. The protocol’s sample-size justification is not reported in the registry record.

Over-dispersion is a general issue when data vary more than an assumed statistical model allows. If a model underestimates variation, standard errors may be too small and uncertainty may appear less than it is. This concept is most directly relevant to models for counts or rates, and the registry record does not identify a count model for the primary continuous time endpoint. There is no basis in the record to say that over-dispersion was assessed or present in this study. It is a general methods consideration, not a description of the study analysis.

Time-to-event methods can account for the timing of an event and, when appropriate, observations for which the event was not observed during follow-up. The primary outcome is expressed as time to bleeding control, but the registry record specifies a mean and standard deviation and does not report a time-to-event analysis. It does not state how a participant without observed control within the timeframe would be handled, whether any observations were censored, or whether all events occurred during observation. Those choices are important for interpreting timing data and are not reported in the registry record.

Overall, the available methods information specifies the endpoint’s definition and intended summary format, and lists assumptions for a separate planning illustration. It does not document the analysis performed, the uncertainty of the primary estimate, missing-data handling, or the assumptions of an inferential model. Those absences limit statistical interpretation; they do not establish that a particular method was or was not used outside the registry record.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("AAJT-S Device Intervention Arm")
n   <- c(4)
m   <- c(2)
sp  <- c(0.01)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  AAJT-S Device Intervention Arm  4  2.000  0.010  1.984  2.016

11. Multiplicity, Missing Data and Analysis Populations

The registry record lists five outcome measures, including time to bleeding control as the primary outcome and hemodynamic stabilization time and long-term maternal recovery status as secondary outcomes. The titles of the other outcome measures are not reported in the registry record. No analyses are listed. Thus, the record does not show which outcomes were analyzed, whether all planned measures were reported, or whether any outcomes were changed or omitted.

Multiplicity arises when several outcomes or statistical tests are considered. In general, examining many outcomes can increase the chance of finding a result that appears notable by chance. A prespecified hierarchy, adjustment procedure, or clear distinction between confirmatory and exploratory analyses can help readers understand how multiple results were handled. The registry record does not report a multiplicity strategy, outcome hierarchy beyond identifying the primary outcome, or inferential results. No claim about adjustment or its absence in the conduct of the study can be made from the available record.

Missing-data methods are also not reported. The record does not state whether any primary or secondary outcome observations were missing, how missing observations were handled, or whether sensitivity analyses were performed. The analysis population is not reported, so it is not possible to determine which enrolled participants contributed to each outcome. Enrollment of 4 does not by itself establish the denominator for any endpoint analysis.

The registry record lists no analyses, and does not describe interim analyses, stopping rules, or a statistical analysis plan. Those details are not reported in the registry record. Without analysis populations, missing-data information, and a multiplicity approach, readers cannot fully assess how the reported outcomes would relate to the study’s planned questions. In this case, numerical outcome analyses are not reported, so multiplicity and missingness cannot be evaluated from observed estimates.

12. Safety Results

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

Deaths

Other (non-serious) adverse events

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

The registry record reports 0 serious adverse events and 0 other adverse events in the AAJT-S Device Intervention Arm. It reports 4 at risk for each of those event categories, and 0 deaths. These figures describe the safety entries recorded for this group; they should not be interpreted as a comparative safety estimate because there is no control group.

A count of zero means that no event in that category was recorded in the registry entry. It does not establish that the underlying risk is zero, particularly when the reported group is small. The figures also do not show how long participants were monitored, what definitions were used for serious and other adverse events, or how events were elicited and adjudicated. Those details are not reported in the registry record.

The registry lists no top serious adverse-event terms. That absence does not add detail about surveillance or establish that no clinically relevant event of any kind occurred. The posted figures should be read narrowly as recorded counts for the specified categories and group, not as evidence that the device is free of safety concerns.

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

The registry record documents a completed proof-of-concept study of AAJT-S use for refractory postpartum haemorrhage and defines a specific immediate endpoint: time from device inflation to visible cessation of external vaginal bleeding. It also describes a clinical rationale for the endpoint, namely temporary control while definitive treatment is prepared. These details explain the question the study was intended to address.

The record does not report the numerical primary outcome. It provides no mean time, standard deviation, confidence interval, p-value, or analysis record. It therefore does not show how quickly bleeding control was observed, how variable the times were, or how precisely an average could be estimated. The named secondary outcomes also have no numerical results reported in the registry record.

The study’s single-group design cannot provide a controlled comparison. The sequence of standard management followed by device application is not a substitute for a concurrent control group, and it does not isolate the device’s contribution from other care or events. Even a favorable within-group observation would not by itself establish comparative effectiveness. Conversely, the absence of a reported numerical endpoint is not evidence that bleeding control did not occur.

The safety entries record 0 serious adverse events, 0 other adverse events, and 0 deaths, with 4 at risk in each listed event category. This is a limited description of recorded events in the study group. It does not establish the absence of risk, describe unreported outcomes, or permit comparison with another treatment.

Accordingly, the record supports a description of the study’s purpose, design, endpoint definition, enrollment, and recorded safety counts. It does not provide enough outcome or analysis information to judge the magnitude, precision, or comparative meaning of the primary result. The result does not establish that the device works or does not work; the registry record does not report the numerical evidence needed for that conclusion.

14. Why This Trial Matters Statistically

This study raises a demanding measurement question: whether visible cessation of external bleeding can be timed after temporary aortic occlusion in severe postpartum haemorrhage. The endpoint is defined with a starting event, an observed stopping event, an assessment method, and a stated timeframe. Those details make the intended measurement understandable and connect it to the stated aim of allowing time for definitive treatment.

Statistically, however, a clear endpoint definition is only the start of interpretation. Readers also need the observed values, the number of observations contributing to the result, and a measure of uncertainty. For a continuous time outcome, the registry record’s intended mean and standard deviation would help describe central tendency and variability if reported. They are not reported in the registry record, so the endpoint cannot be evaluated quantitatively.

The single-group design also highlights the distinction between feasibility or proof-of-concept observations and comparative evidence. A description of what happened after device application may inform whether the procedure can be studied further, but without a comparator it cannot estimate a contrast against another approach. The registry record does not report a comparative effect, and its design does not include a control arm.

The safety figures are also informative as a record of what was entered, but their interpretation depends on context such as observation duration, definitions, and ascertainment methods. Those details are not reported in the registry record. Zero recorded events in the listed categories should not be mistaken for a precise estimate of safety.

This trial matters statistically because it illustrates the difference between a well-defined research question and a reported, interpretable result. The registry captures the target population and endpoint concept, but not the numerical primary outcome or its uncertainty. Transparent outcome reporting is necessary for readers to distinguish an intended measure from evidence about what was observed.

15. 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 principal limitation for interpretation is the absence of a reported numerical primary endpoint. Although the endpoint is defined as time to visible cessation of external vaginal bleeding, the mean and standard deviation are not reported in the registry record. No confidence interval, p-value, or analysis record is listed. The primary result’s magnitude and precision therefore cannot be assessed.

Enrollment is 4, but the registry does not report the analysis population or the denominator contributing to each outcome. Missing outcome data, if any, and their handling are not reported in the registry record. The available information cannot establish whether the primary measure was obtained for every enrolled participant.

The design is single-group, with allocation listed as NA and masking as NONE. There is no concurrent comparator, so the study cannot provide a direct estimate of a difference against another treatment. Standard management before device application is described, but it is not a control group. The registry record also does not provide enough detail to assess how accompanying care or other clinical circumstances were accounted for.

The endpoint relies on visual clinical assessment by the attending provider. The record does not report additional measurement procedures, assessor training, or steps to standardize assessment. These details could matter when determining the timing of a visually assessed event, but they are not reported in the registry record.

The arm description is incomplete, and the full device application procedure is not reported. The registry lists five outcome measures, but only the primary and two secondary outcome titles are available in the record details; the other outcome titles are not reported in the registry record. Follow-up details, missing-data methods, multiplicity handling, interim analyses, and the statistical analysis plan are also not reported. These limitations concern what can be established from the registry entry and should not be treated as claims about procedures beyond that record.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Temporary Aortic Occlusion With the Abdominal Tourniquet for Refractory Postpartum Haemorrhage: A Proof-of-Concept Study in a War-Affected Region — NCT07016568.
• Registry record last updated 2025-10-20; status last verified 2025-10.
• Results first posted 2025-10-20.
• 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.

19. Record Summary

The registry record identifies NCT07016568 as a completed, single-group proof-of-concept study of the Abdominal Aortic and Junctional Tourniquet - Stabilized (AAJT-S) for refractory postpartum haemorrhage. Enrollment is 4. The listed primary outcome is time from device inflation to visible cessation of external vaginal bleeding, summarized as a mean and standard deviation within 10 minutes of application. The named secondary outcomes are hemodynamic stabilization time and long-term maternal recovery status.

Allocation is listed as NA, masking as NONE, and the study model as SINGLE GROUP. The sponsor is LLC UkrMedGroup. The record lists 0 serious adverse events, 0 other adverse events, and 0 deaths, with 4 at risk in each adverse-event category. It lists no analyses. The numerical primary outcome, analysis population, missing-data approach, and statistical analysis plan are not reported in the registry record. Therefore, the study question and design can be described, but the primary outcome’s magnitude and precision cannot be assessed from the posted results.