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 Comparison of 24-hours Versus 72-hours of Octreotide Infusion in Preventing Early Rebleed From Esophageal Varices (NCT03624517), a randomized phase 4 study. The primary outcome is Esophageal Varices Rebleed Within 72-hours After Control of Initial Bleed.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03624517 |
| Phase | Phase 4 |
| Condition | Esophageal Varices, Liver Cirrhoses, Bleeding Esophageal Varices |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 34 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Medical University of South Carolina |
| Results posted | Yes |
2. Clinical Question
Population
The study concerns cirrhotic patients with bleeding esophageal varices who received endoscopic therapy to control an initial bleed. The registry record describes treatment after variceal banding. Detailed eligibility criteria and additional participant characteristics are not reported in the registry record.
Intervention
One group received an octreotide infusion over 72 hours after the initial bleed was controlled. Octreotide is the listed drug intervention. The registry record describes the study as evaluating safety and efficacy alongside endoscopic therapy.
Comparator
The comparison group received an octreotide infusion over 24 hours. Both groups are described as receiving octreotide; the planned contrast is the duration of infusion, rather than octreotide versus no octreotide.
Primary question
The primary question is whether the number of participants with esophageal-varices rebleeding within 72 hours after control of the initial bleed differed between the 72-hour and 24-hour infusion groups. The posted result records 1 event among 19 participants in the 72-hour group and 0 among 15 in the 24-hour group. These small event counts make the estimated difference imprecise.
The record also lists rebleeding and survival outcomes at 7 days and 30 days after control of the initial bleed. Numerical results for those secondary outcomes are not reported in the registry record. The clinical question is therefore best read as a comparison of two infusion durations for early rebleeding, with the posted primary result addressing the specified 72-hour period. It does not answer whether either infusion duration is better than no infusion, or establish effects for outcomes whose results are not posted.
3. Trial Design
The registry identifies NCT03624517 as a phase 4, randomized, single-masked, parallel-group study. It compares a 24-hour octreotide infusion with a 72-hour octreotide infusion, each in the context of endoscopic therapy. The registry lists the Medical University of South Carolina as sponsor. Recorded enrollment is 34.
The trial start date is 2018-09-19, and the primary completion date is 2024-12-01. The current status is listed as terminated. A reason for termination, details about the timing of termination, and information about whether termination affected recruitment or follow-up are not reported in the registry record. A planned recruitment target and the reason for selecting it are also not reported.
Randomized allocation means the study was designed to assign participants to treatment groups by chance. The allocation procedure, concealment methods, and randomization ratio are not reported in the registry record. The record says the study was single-masked, but does not identify which people involved in the trial were masked or explain how masking was maintained. It is therefore not possible to assess those design details from the record.
The posted primary outcome counts are 0 participants with the event among 15 in the 24-hour group and 1 among 19 in the 72-hour group. These arm counts accompany the primary result; the record does not describe the analysis population or explain how participants with missing outcome information were handled. No analysis methods are listed. The study is described as multi-center in its official title, but further information about sites or site-level recruitment is 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 | 24-hour octreotide infusion | 72-hour octreotide infusion |
|---|---|---|
| STARTED | 15 | 19 |
| COMPLETED | 15 | 19 |
| NOT COMPLETED | 0 | 0 |
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 | 24-hour Octreotide Infusion | 72-hour Octreotide Infusion | Total |
|---|---|---|---|---|
| Participants analysed | 15 | 19 | 34 | |
| Age, Continuous | years | 52 (SD 16) | 54 (SD 11) | 53.12 (SD 13.06) |
| Sex: Female, Male: Female | Participants | 7 | 6 | 13 |
| Sex: Female, Male: Male | Participants | 8 | 13 | 21 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 3 | 0 | 3 |
| Race (NIH/OMB): White | Participants | 11 | 16 | 27 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 1 | 3 | 4 |
| Region of Enrollment: United States | participants | 15 | 19 | 34 |
6. Primary Endpoint
The registry lists the primary outcome as Esophageal Varices Rebleed Within 72-hours After Control of Initial Bleed, measured over 72 hours.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the count of participants with esophageal-varices rebleeding within 72 hours after control of the initial bleed. The registry defines rebleeding through a list of clinical criteria: a drop in hemoglobin by more than 20 percentage points from baseline; sustained tachycardia above 100 beats per minute, with or without hematochezia or melena; transfusion of >2 units of packed red blood cells after esophageal band ligation; recurrence of hematemesis or ongoing melena; or an urgent or emergent need for a transjugular intrahepatic portosystemic shunt to control suspected rebleeding.
The endpoint counts participants who experienced an event, rather than measuring the severity or duration of an event. In general, a binary endpoint turns each participant’s outcome into an event or no-event classification over a defined period. This can make a direct comparison between groups possible, but the interpretation depends on the event definition and on complete, consistent outcome assessment. The record does not report how the criteria were adjudicated, whether assessors were masked, or how cases meeting more than one criterion were handled.
The 72-hour window is the stated primary timeframe and is aligned with the longer infusion duration. The endpoint is used to assess early rebleeding after control of the initial bleed; it does not by itself describe later rebleeding, survival, or other aspects of safety. Numerical results for the separately listed 7-day and 30-day outcomes are not reported in the registry record.
7. Results Posted in the Registry
- 72-hour octreotide infusion: 5.3% (1/19) versus 0.0% (0/15) on control; risk difference 5.3 percentage points (95% CI -4.8 to 15.3); unadjusted two-proportion z-test p = 0.367.
Risk difference: 72-hour octreotide infusion
95% CI: -4.8 to 15.3 percentage points
Recalculated from the posted summary statistics
8. Statistical Interpretation
In the posted primary results, no participant in the 24-hour group experienced the defined rebleeding event within 72 hours, while 1 participant in the 72-hour group did. The reported risk difference, comparing the 72-hour group with the 24-hour group, is 0.053. The point estimate is positive, meaning the observed event proportion was higher in the 72-hour group in this sample. With only one event across the two groups, that direction should not be treated as a stable estimate of the difference that might occur in a broader population.
The confidence interval for the risk difference runs from -0.048 to 0.153. It includes zero, the value corresponding to no difference in event risk, and also spans values on either side of zero. The data therefore do not determine the direction or size of a population difference with precision. The reported unadjusted p-value is 0.367. The registry record does not report a prespecified decision threshold or a detailed statistical analysis plan, so the p-value should be read alongside the estimate, interval, and very small event count, rather than as a standalone verdict.
This result does not establish that the infusion durations have equal effects. A failure to distinguish the groups in a small trial can reflect limited information, particularly when the event is uncommon in the observed sample. Conversely, the positive point estimate does not establish that the 72-hour duration increases rebleeding. The interval remains compatible with effects in either direction, and the registry does not report a powered equivalence or non-inferiority analysis.
The record lists two secondary outcomes: rebleeding at 7 days and 30 days, and survival at 7 days and 30 days after control of the initial bleed. Their numerical results are not reported. As a result, the early primary endpoint is the only outcome with a posted between-group estimate in the registry record. The record lists adverse-event counts separately, but does not provide a causal assessment linking events to treatment. Overall, the primary result is a descriptive comparison with substantial uncertainty, not a definitive estimate of the relative effects of the two infusion durations.
9. Statistical Methods Explained
The primary outcome is binary: each participant is classified according to whether the defined rebleeding event occurred within the stated 72-hour timeframe. For a binary outcome, the risk in a group is the proportion of participants in that group who experienced the event. A risk difference subtracts the comparator group’s risk from the other group’s risk. Here the comparison is stated as 72-hour infusion versus 24-hour infusion, and the posted risk difference is 0.053. A positive value means the observed event risk was higher in the 72-hour group; a negative value would mean it was lower. The point estimate describes the observed data and does not, by itself, establish a causal or generalizable effect.
What does the confidence interval add?
A confidence interval gives a range of values compatible with the observed data under the statistical procedure used to construct it. It communicates uncertainty around an estimate more directly than a point estimate alone. The reported interval, -0.048 to 0.153, includes zero and values below and above zero. This indicates that the posted data do not pin down whether the underlying difference favors one duration or the other. The exact interval method is not reported in the registry record, so its assumptions cannot be checked from the record.
How should the p-value be read?
The unadjusted p-value is 0.367. In general, a p-value measures how unusual data at least as incompatible with a specified null model would be if that model were true, according to the chosen statistical test. It is not the probability that the null hypothesis is true, and it does not measure the probability that the result is due to chance. The statistical test and its assumptions are not reported in the registry record. The p-value should not replace consideration of the effect estimate, confidence interval, outcome counts, and study design.
Why do the event counts matter?
The observed comparison is based on 0 events in the 24-hour group and 1 in the 72-hour group. When event counts are this small, a single outcome can have a large influence on the estimated difference. The data consequently provide limited information about the range of differences that might be seen in a larger study. This is a general statistical concern, not a claim about any unreported analysis. The record does not report a method for handling sparse data or state whether an alternative analysis was considered.
What are the planning illustrations?
The registry record describes sample-size planning illustrations based on the observed effect, with two-sided significance level 0.05, equal allocation, and a normal approximation. The effect to detect is described as a fraction of the observed effect. These are planning calculations rather than evidence about how the trial was designed; they should not be read as observed power. The record does not report the trial’s own sample-size justification or the assumptions used to choose its enrollment target. Illustrations based on a small observed effect estimate can be especially sensitive to uncertainty in that estimate, so they are not a substitute for a prospectively specified design rationale.
For general planning, a power calculation asks how much information a proposed study would need to detect a chosen effect under specified assumptions. It does not show that a completed study had adequate power, nor does it change the uncertainty in the observed result. The registry’s planning assumptions are stated, but the calculated planning values are not included among the registry entries reported for this explanation. The record also does not report interim analyses, stopping rules, adjustment for multiple comparisons, or a detailed statistical analysis plan. Without those details, the posted estimate and interval can be described, but the full analytic pathway cannot be reconstructed.
10. Confidence Intervals and Precision
The estimate of the risk difference is 0.053, with a confidence interval from -0.048 to 0.153. The interval is wide relative to the point estimate and crosses zero. It therefore reflects substantial uncertainty about both the direction and magnitude of the difference. The posted data are compatible with a lower event risk in the 72-hour group, little or no difference, or a higher event risk in that group, within the range represented by the interval and its assumptions.
Confidence intervals are useful because they show how much the estimate may vary under repeated sampling and a specified statistical method. They are not a guarantee that the true effect lies within a particular interval, and they do not assign probabilities to individual values inside it. The registry record does not identify the interval-construction method, so method-specific interpretation is not possible.
Precision is limited in this result because the event counts are sparse: the observed counts are 0 and 1. A single event has substantial influence when so few events are observed. The arm sizes are recorded as 15 and 19, but those figures alone do not establish how many participants contributed complete endpoint data or whether all randomized participants were included in the analysis. Analysis-population details are not reported in the registry record.
The interval should therefore carry more interpretive weight than the point estimate alone. The positive point estimate is not a precise prediction, and the inclusion of zero does not prove that the durations are equivalent. A more precise comparison would require more information, but the registry record does not provide a basis for specifying how much additional information would be needed for a particular clinical decision.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary rebleeding outcome within 72 hours and two secondary outcome descriptions: rebleeding at 7 days and 30 days, and survival at 7 days and 30 days after control of the initial bleed. The record lists 3 outcome measures and 0 analyses. Numerical results for the secondary outcomes are not reported in the registry record. It is consequently not possible to compare those outcomes with the primary result or assess whether the findings are consistent across follow-up periods.
When a study examines multiple outcomes or multiple comparisons, the chance of finding at least one apparently notable result can increase. Statistical methods may address this multiplicity, depending on the study’s aims and analysis plan. The registry record does not report whether a multiplicity strategy was prespecified or used. It also does not report a detailed analysis plan, so there is no basis to determine which analyses were planned in advance or how the primary and secondary outcomes were treated statistically.
Missing-data handling is not reported. The record does not say whether any participants lacked a 72-hour outcome assessment, how missing outcomes were classified, or whether any imputation or sensitivity analysis was used. The posted arm counts and event counts do not resolve these questions. The analysis population is also not reported: the record does not say whether the primary comparison included all randomized participants or followed another rule.
These gaps limit interpretation of both the numerical estimate and its potential susceptibility to analysis choices. They do not demonstrate that missing data or multiplicity affected the result; they mean that the registry record does not document how those issues were addressed. The reported primary comparison can still be described as posted, but its analytic context remains incomplete.
12. 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 |
|---|---|---|---|
| 24-hour octreotide infusion | 0 | 15 | 0.0% |
| 72-hour octreotide infusion | 1 | 19 | 5.3% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| 24-hour octreotide infusion | 0 of 15 |
| 72-hour octreotide infusion | 1 of 19 |
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 |
|---|---|
| 24-hour octreotide infusion | 2 of 15 |
| 72-hour octreotide infusion | 8 of 19 |
Most frequent serious adverse event terms
| Event term | Organ system | 24-hour octreotide infusion | 72-hour octreotide infusion |
|---|---|---|---|
| Death (Sepsis) | General disorders | 0 of 15 | 1 of 19 |
Most frequent non-serious adverse event terms
| Event term | Organ system | 24-hour octreotide infusion | 72-hour octreotide infusion |
|---|---|---|---|
| Mechanical Ventilation >12h | Respiratory, thoracic and mediastinal disorders | 1 of 15 | 2 of 19 |
| Dysphagia/Odynophagia | Gastrointestinal disorders | 0 of 15 | 2 of 19 |
| Nasogastric Tube Insertion | Gastrointestinal disorders | 0 of 15 | 2 of 19 |
| Vasopressor Use | Vascular disorders | 1 of 15 | 1 of 19 |
| Infection | Infections and infestations | 0 of 15 | 1 of 19 |
Serious events with the highest arm-level rate: death (sepsis) (5.3%).
The posted serious adverse-event figures are 0 participants affected among 15 in the 24-hour group and 1 among 19 in the 72-hour group. The record lists 0 deaths in the 24-hour group and 1 in the 72-hour group. The serious-event term listed is “Death (Sepsis),” with 5.3% recorded. These figures describe what is posted; they do not establish that an event was caused by octreotide or by the duration of infusion. A causal assessment is not reported in the registry record.
The record also lists other adverse events affecting 2 participants in the 24-hour group and 8 in the 72-hour group. The registry distinguishes these from serious adverse events, but further definitions, event-level details, severity grading, and attribution are not reported. The counts are not adjusted comparisons, and the record does not provide a statistical analysis of safety outcomes. With these group sizes and the limited detail available, the counts should be treated as descriptive rather than as a precise estimate of relative safety.
Adverse-event counts answer a different question from the primary rebleeding endpoint. They should not be combined with that endpoint or interpreted as proof for or against a treatment effect. The record does not report a full account of safety monitoring or how events were collected.
13. What the Result Does, and Does Not, Mean
The result means that, among participants represented in the posted primary outcome counts, 0 in the 24-hour group and 1 in the 72-hour group met the registry’s definition of rebleeding within 72 hours. The estimated risk difference was 0.053, comparing 72-hour with 24-hour infusion. Its confidence interval, -0.048 to 0.153, indicates considerable uncertainty and includes zero. The unadjusted p-value is 0.367.
This does not show that the two infusion durations have identical effects. A non-significant or imprecise result is not evidence of equivalence unless the study was designed and analyzed to assess equivalence, and such an analysis is not reported. Nor does the positive point estimate prove that the longer infusion increases rebleeding. The small number of observed events leaves the direction and size of any population difference uncertain.
The result also does not answer whether octreotide is effective compared with no octreotide, because both groups received an octreotide infusion. It addresses the duration contrast within the described endoscopic-treatment setting. It cannot establish the effects of either duration on outcomes beyond the posted primary endpoint. Although the record lists rebleeding and survival outcomes at 7 days and 30 days, their numerical results are not reported.
Safety counts should be interpreted separately. The record gives counts for serious and other adverse events, but does not report causal attribution or detailed safety analyses. The study’s terminated status and missing information about the reason for termination, recruitment, analysis population, and missing outcomes add important context. Taken together, the posted findings are limited evidence from a small randomized comparison, not a definitive answer about the relative effects of the two infusion durations.
14. Why This Trial Matters Statistically
This trial is statistically instructive because the estimated contrast is based on very few primary events. In that setting, the point estimate can appear concrete while remaining highly uncertain. Reading the risk difference together with its confidence interval and the underlying counts helps prevent overinterpretation of a single event or of the direction of the estimate.
The study also illustrates why a randomized design does not remove every interpretive limitation. Randomization is intended to support a fair comparison, but the registry record does not provide the allocation procedure, masking details, analysis population, missing-data approach, or a detailed statistical plan. These details help readers assess how the intended design was carried through and how the reported estimate was obtained.
The distinction between a primary endpoint and listed secondary outcomes matters as well. The 72-hour rebleeding result is posted, but numerical results for the listed 7-day and 30-day rebleeding and survival outcomes are not. Without those results, the short-term primary comparison cannot be extended to later outcomes. Likewise, descriptive safety counts do not establish causation or substitute for a complete safety analysis.
Finally, the record describes planning illustrations based on the observed effect, while the trial’s own design justification is not reported. Planning calculations based on an observed estimate should not be confused with evidence that the completed trial had a particular power. This distinction is especially important when the observed estimate is uncertain. The record’s terminated status also makes transparent reporting of recruitment, follow-up, and analysis choices valuable for understanding the limits of the evidence.
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 primary comparison has few observed events, which limits the precision of the risk-difference estimate. The confidence interval spans zero and extends in both directions, so the posted result does not establish the direction of a population effect. Recorded enrollment is 34, and the arm counts for the primary result are 15 and 19; the registry record does not explain whether all randomized participants contributed outcome data.
The study is listed as terminated, but the reason and its implications are not reported. Recruitment progress, follow-up completeness, and any effect of termination on the study’s ability to address its original aims are not described. The record also does not report the sample-size justification or a detailed statistical analysis plan. As a result, the rationale for the enrollment target and the planned analytic approach cannot be assessed.
Several design and analysis details remain unavailable: the randomization procedure, the identity of the masked parties, outcome-assessment procedures, analysis population, missing-data handling, and the method used to calculate the confidence interval and p-value. No analyses are listed in the record. The secondary outcomes are named but lack numerical results, limiting assessment beyond the primary 72-hour endpoint.
The endpoint definition includes several possible clinical criteria, but the record does not describe adjudication or how disagreements were resolved. Safety reporting is also limited to group counts and a listed serious-event term; event details, attribution, and a statistical comparison are not reported. These limitations do not invalidate the posted results, but they restrict how confidently the results can be interpreted or generalized beyond the study as recorded.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Comparison of 24-hours Versus 72-hours of Octreotide Infusion in Preventing Early Rebleed From Esophageal Varices — NCT03624517.
- Registry record last updated 2025-11-20; status last verified 2025-11.
- Results first posted 2025-11-20.
- 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.
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19. Record Summary
NCT03624517 is a phase 4, randomized, single-masked, parallel-group study comparing 24-hour and 72-hour octreotide infusions alongside endoscopic therapy for bleeding esophageal varices. Recorded enrollment is 34. The study is listed as terminated; its start date is 2018-09-19 and its primary completion date is 2024-12-01. The sponsor is the Medical University of South Carolina.
The primary outcome is rebleeding within 72 hours after control of the initial bleed. The posted counts are 0 among 15 participants in the 24-hour group and 1 among 19 in the 72-hour group. The risk difference is 0.053, with a confidence interval from -0.048 to 0.153 and an unadjusted p-value of 0.367. The interval and sparse event counts indicate substantial uncertainty.
Rebleeding and survival at 7 days and 30 days are listed as secondary outcomes, but their numerical results are not reported in the registry record. Details about the reason for termination, statistical plan, missing data, and analysis population are also not reported.