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 Clinical Trial of Standard Versus Goal-Directed Perioperative Fluid Management (GDT) for Patients Undergoing Liver Resection (NCT01596283), a randomized phase 3 study. The primary outcome is Postoperative Complications.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01596283 |
| Phase | Phase 3 |
| Condition | Liver Cancer |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 135 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Memorial Sloan Kettering Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing liver resection for liver cancer were the population of interest. The registry record reports 135 participants enrolled. It does not provide further eligibility details or a fuller description of the primary-outcome analysis population.
Intervention
The intervention was goal-directed fluid therapy. The registry description says the approach used a computerized system to guide fluid administration using real-time information. The intervention listing names the Edwards EV1000 system, while the brief summary refers to FloTrac; the registry record does not explain this difference.
Comparator
The comparator was standard fluid management. The brief summary describes fluid amounts guided by weight, blood pressure, heart rate and urine output. The registry does not provide a more detailed standardized treatment algorithm for either arm.
Primary question
The stated primary endpoint was postoperative complications within 30 days after the procedure. The central question was whether the recorded incidence of these complications differed between the standard-management and goal-directed groups. The registry record does not report a single numerical comparison of that primary endpoint.
3. Trial Design
This was a randomized, parallel-group, Phase 3 trial comparing standard fluid management with goal-directed fluid therapy for patients undergoing liver resection. The record lists 135 enrolled participants and describes the study as completed. It also identifies the trial as single-masked; the identity of the masked party is not reported in the registry record.
The arm descriptions state that patients were consented before surgery and randomized in the operating room after the liver had been resected, using envelopes. Thus, the treatment assignment described in the record occurred during the operation, after resection. Both arm descriptions repeat this process. The registry does not report further details about how the envelopes were prepared, safeguarded or opened.
The study start is recorded as 2012-04, and primary completion as 2016-05. The standard arm is described as using conventional fluid-management indicators, while the goal-directed arm used a computerized system. The brief summary names FloTrac, whereas the intervention listing names the Edwards EV1000 system. The registry does not reconcile these names, so the exact relationship between them should not be assumed.
Secondary outcomes listed include low cardiac output time, perioperative and postoperative fluid volume, and postoperative length of stay. The record lists 5 outcome measures but does not provide a single primary-outcome comparison. Detailed protocol procedures, allocation concealment methods, masking procedures and the statistical analysis plan 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 | Goal-directed Therapy (GDT) After Liver Resection | Standard Perioperative Resuscitation After Liver Resection |
|---|---|---|
| STARTED | 69 | 66 |
| COMPLETED | 69 | 66 |
| 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 | Goal-directed Therapy | Standard Perioperative Resuscitation | Total |
|---|---|---|---|---|
| Participants analysed | 69 | 66 | 135 | |
| Age, Continuous | years | 55 (SD 13) | 58 (SD 14) | 57 (SD 13) |
| Sex: Female, Male: Female | Participants | 36 | 39 | 75 |
| Sex: Female, Male: Male | Participants | 33 | 27 | 60 |
| Region of Enrollment: United States | Participants | 69 | 66 | 135 |
6. Primary Endpoint
The registry lists the primary outcome as Postoperative Complications, measured over 30 days post procedure.
| Element | Registry entry |
|---|---|
| Result type | Count Of Participants |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was postoperative complications, measured as the number of participants with complications within 30 days after the procedure. The record says complications were defined in the MSKCC Adverse Events Program, organized by organ-system categories, divided into specific complications and graded. It describes incidence of overall complications, but does not report a single numerical result for that endpoint or a comparison between the randomized groups.
A complication endpoint is used to capture unwanted events arising after surgery across different organ systems. Combining individual complications into an overall measure can represent a broad burden of postoperative morbidity, while category and grade information can retain distinctions about the kinds and severity of events. Interpretation depends on how the categories are defined, how events are assessed and how missing observations are handled. Those operational details, beyond the registry description, are not reported in the registry record.
The endpoint is a participant count, not a continuous measurement such as fluid volume or length of stay. A participant-level event count can be summarized as the number with at least one event, but the registry record does not clarify whether multiple complications in one participant were counted once or in more than one category. The record also does not state the analysis population or provide an effect estimate, confidence interval or significance test for the primary endpoint.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record describes a randomized comparison and identifies postoperative complications within 30 days as the primary endpoint. It does not report the primary endpoint as a single comparison between the groups. The record notes that the primary outcome has several categories or time points and was not reduced to one comparison. As a result, the posted information does not establish the direction, size or precision of a primary-outcome difference.
The serious adverse-event figures are descriptive counts. The standard-fluid-management group lists 23 participants with a serious adverse event among 66 at risk; the goal-directed-fluid-therapy group lists 46 among 69 at risk. The record also lists 0 deaths in the standard group and 3 in the goal-directed group. These figures describe what was recorded in the registry; they are not, on their own, an adjusted comparison or evidence that treatment assignment caused an event. No uncertainty intervals or inferential tests for these adverse-event counts are reported in the registry record.
Several reasons make caution important. The registry gives no detailed account of the adverse-event ascertainment or adjudication process, and it does not report whether any participants were excluded from a particular analysis. It also does not state whether the groups were analyzed according to randomized assignment or according to treatment received. Without this information and a prespecified statistical analysis, readers cannot assess how the recorded counts relate to the trial's planned analysis.
Other listed serious-event terms include intra-abdominal infection or abscess, pleural effusion, ascites, non-infected intra-abdominal/intra-thoracic fluid collection, renal failure and liver dysfunction/failure. Their reported percentages describe entries in the registry, but the record does not provide arm-specific values for each term in the listed summary. They should not be read as comparative treatment effects.
The registry lists 0 analyses. This is consistent with the absence of a reported primary-outcome comparison in the record. It does not mean that no analysis was conducted; it means that a statistical analysis is not posted in the registry record. The available information supports describing the design and the recorded safety counts, but not drawing a conclusion about the relative effect of the two fluid-management strategies.
9. Statistical Methods Explained
The trial is described as randomized and parallel-group. Randomization is a method for assigning participants to treatment groups by chance. When carried out as intended, it helps make groups comparable in expectation with respect to measured and unmeasured characteristics. It does not guarantee that groups will be identical, particularly in a trial of this size. The record says randomization occurred in the operating room after the liver had been resected, using envelopes. Further details about sequence generation and allocation concealment are not reported in the registry record.
What does a binary endpoint mean?
The primary endpoint is recorded as a count of participants with an event. This is a binary participant-level outcome: a participant either meets the endpoint definition or does not. A comparison of binary outcomes can be expressed in different ways, such as a difference in event proportions or a relative measure. The choice of measure affects interpretation, and should be specified in an analysis plan. The registry record does not report a primary-outcome effect estimate or identify the measure used for one.
The endpoint combines postoperative complications described across organ systems and severity grades. Before analyzing such an endpoint, investigators need operational rules for deciding which events qualify, how multiple events in the same participant are counted and how assessments across the follow-up period are combined. The registry describes the broad classification system, but these detailed rules and the handling of multiple complications are not reported in the registry record.
How should a confidence interval be read?
General statistical explanation: a confidence interval expresses the uncertainty around an estimated effect under a specified analysis. A narrower interval indicates greater precision than a wider interval, while the interval's location indicates which effect values remain compatible with the data and method. A confidence interval does not repair limitations in endpoint definition, follow-up or analysis. The registry record does not report a confidence interval for the primary endpoint or for the serious adverse-event counts.
A significance test and a confidence interval answer related but different questions. A test evaluates how compatible the data are with a specified null hypothesis under its assumptions. A confidence interval presents a range of effect values compatible with the observed data and model. Neither alone establishes clinical importance or causation. The registry record does not report a primary-outcome test, a p-value or an analysis model.
Why does the analysis population matter?
General statistical explanation: an intention-to-treat analysis generally retains participants in their randomized groups, while other analysis populations may depend on treatment received or protocol adherence. These approaches can answer different questions and may be affected differently by deviations from assigned treatment. The registry record does not state which analysis population was planned or used, or how protocol deviations were handled.
Missing outcome data can also affect a binary endpoint. If outcome status is unavailable for some participants, the analysis must state how those participants are treated and whether assumptions or sensitivity analyses are used. The registry record does not report missing-data counts, methods for handling missing observations or sensitivity analyses. It is therefore not possible to assess the effect of missing data on the primary endpoint from the posted record.
What can be inferred from the sample-size approach?
General statistical explanation: a sample-size calculation is a planning exercise that links a target effect, a significance level, allocation and assumptions about the outcome to a number of participants. The registry's described planning illustrations are based on the observed effect, use a two-sided significance level of 0.05, assume equal allocation and a normal approximation, and consider stated fractions of that observed effect. Such illustrations are not the trial's original design justification and are not observed power. The registry record does not report the trial's own sample-size justification.
Post hoc power calculations based on an observed effect do not provide an independent measure of the evidence. Precision is more directly conveyed by an effect estimate and its confidence interval. The record does not report the primary-outcome effect and uncertainty needed to interpret such precision. The listed sample-size assumptions should therefore be understood only as planning illustrations, not as proof that the trial was adequately or inadequately powered.
Multiplicity arises when investigators examine several endpoints, categories or time points. Testing many hypotheses can increase the chance of at least one apparently notable result unless the analysis plan controls or otherwise addresses this issue. Because the primary endpoint involves multiple categories or time points and is not reduced to one comparison in the registry, the record does not establish how multiplicity was handled. No adjustment method or hierarchy of endpoints is reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The primary endpoint is described as overall postoperative complications, with events organized by organ system, specific complication and grade. The registry notes that the primary outcome has several categories or time points and is not reduced to one comparison. It does not report which categories or time points were intended for formal testing, whether one was designated as primary within that structure, or how multiple comparisons were handled. A multiplicity strategy is not reported in the registry record.
The registry also lists secondary outcomes: low cardiac output time, total perioperative fluid volume, total postoperative fluid volume and postoperative length of stay. The record does not state whether these were tested in a prespecified order, whether their results were adjusted for multiple testing or whether they were descriptive. No inferential analyses are posted.
Missing-data counts and methods are not reported in the registry record. The record does not specify how incomplete 30-day complication assessments, withdrawals or other unavailable endpoint information were handled. It also does not report a statistical analysis population, such as an intention-to-treat or per-protocol population, or explain how deviations from assigned management were treated.
These omissions limit interpretation. Different analysis populations and missing-data assumptions can change an estimate, while unaddressed multiplicity can make isolated findings harder to interpret. The available record does not permit assessment of those issues for the primary endpoint.
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 |
|---|---|---|---|
| Standard Fluid Management | 23 | 66 | 34.8% |
| Goal Directed Fluid Therapy | 46 | 69 | 66.7% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Standard Fluid Management | 0 of 66 |
| Goal Directed Fluid Therapy | 3 of 69 |
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 |
|---|---|
| Standard Fluid Management | 66 of 66 |
| Goal Directed Fluid Therapy | 69 of 69 |
Most frequent serious adverse event terms
| Event term | Organ system | Standard Fluid Management | Goal Directed Fluid Therapy |
|---|---|---|---|
| Intra-abdominal infection or abscess | Infections and infestations | 9 of 66 | 13 of 69 |
| Ascites | Gastrointestinal disorders | 5 of 66 | 8 of 69 |
| Pleural Effusion | Respiratory, thoracic and mediastinal disorders | 1 of 66 | 9 of 69 |
| Renal Failure | Renal and urinary disorders | 1 of 66 | 3 of 69 |
| Non-infected intra-abdominal/intra-thoracic fluid collection | Respiratory, thoracic and mediastinal disorders | 3 of 66 | 0 of 69 |
| Biliary anastomotic leak | Hepatobiliary disorders | 1 of 66 | 2 of 69 |
| Biloma | Hepatobiliary disorders | 1 of 66 | 2 of 69 |
| Sepsis | Infections and infestations | 1 of 66 | 2 of 69 |
| Wound infection | Infections and infestations | 1 of 66 | 1 of 69 |
| Liver dysfunction/failure | Hepatobiliary disorders | 0 of 66 | 2 of 69 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Standard Fluid Management | Goal Directed Fluid Therapy |
|---|---|---|---|
| Alanine aminotransferase increased | Investigations | 66 of 66 | 69 of 69 |
| Aspartate aminotransferase increased | Investigations | 66 of 66 | 69 of 69 |
| Hyperglycemia | Metabolism and nutrition disorders | 66 of 66 | 69 of 69 |
| Hypoalbuminemia | Metabolism and nutrition disorders | 66 of 66 | 69 of 69 |
| Intra-abdominal infection of abscess | Infections and infestations | 10 of 66 | 13 of 69 |
| Wound infection | Infections and infestations | 7 of 66 | 5 of 69 |
| Liver dysfunction/failure | Hepatobiliary disorders | 1 of 66 | 4 of 69 |
| Biliary anastomotic leak | Hepatobiliary disorders | 2 of 66 | 3 of 69 |
| Ascites | Gastrointestinal disorders | 3 of 66 | 2 of 69 |
| Ileus, paralytic | Gastrointestinal disorders | 3 of 66 | 2 of 69 |
Serious events with the highest arm-level rate: intra-abdominal infection or abscess (18.8%), pleural effusion (13.0%), ascites (11.6%), non-infected intra-abdominal/intra-thoracic fluid collection (4.5%), renal failure (4.3%).
The registry lists serious adverse-event counts separately for the two groups. For standard fluid management, 23 participants with a serious adverse event are recorded among 66 at risk. For goal-directed fluid therapy, 46 are recorded among 69 at risk. The death counts are 0 and 3, respectively. These are descriptive registry figures; no confidence intervals, adjusted estimates or statistical tests are reported for them.
The record also lists serious-event terms with percentages: intra-abdominal infection or abscess, 18.8%; pleural effusion, 13.0%; ascites, 11.6%; non-infected intra-abdominal/intra-thoracic fluid collection, 4.5%; renal failure, 4.3%; and liver dysfunction/failure, 2.9%. The listed summary does not give arm-specific percentages for these terms. The registry record does not clarify the denominator or whether participants could contribute to more than one term, so the percentages should not be treated as mutually exclusive or as a direct comparison between groups.
Serious-event counts do not by themselves establish that an event was caused by the assigned fluid strategy. The registry record does not report event attribution, timing by group or detailed ascertainment procedures. The figures describe recorded safety events, not a causal conclusion.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized, parallel-group trial compared standard fluid management with goal-directed fluid therapy during liver resection and identifies 30-day postoperative complications as its primary endpoint. It also reports serious adverse-event counts and deaths for each group. These details describe the study question, design and some posted safety information.
The record does not provide a single primary-outcome comparison. It therefore does not show how the groups compared on the stated primary endpoint, how large any difference might have been or how precisely such a difference was estimated. The absence of a posted comparison is not evidence that the treatments had the same effect, nor is it evidence that one was better. It means the registry record does not provide the information needed to assess that question.
The serious-event counts should be read as descriptive rather than causal. Randomization supports comparative inference when outcomes are analyzed appropriately, but interpretation also depends on event definitions, completeness of follow-up, the analysis population and the statistical method. Those details and inferential results are not reported in the registry record. The deaths and serious-event counts alone cannot establish whether the assigned strategy caused a difference.
The registry's brief summary describes a computer-guided approach, and the intervention listing names the Edwards EV1000 system. The brief summary also refers to FloTrac; the relationship between the names is not explained in the record. The exact intervention as implemented should therefore not be inferred beyond the registry descriptions.
Overall, the posted information supports a careful account of the trial design and recorded safety figures, but not a conclusion about comparative efficacy or harm. Any stronger interpretation would require the full outcome data, an analysis plan and information about participant follow-up and analysis methods, none of which is reported in the registry record.
13. Why This Trial Matters Statistically
This trial raises a statistical question that is important in perioperative research: how to compare management strategies when the primary outcome comprises complications that can arise in different organ systems and vary in grade. A broad complication endpoint can capture overall postoperative burden, but its interpretation depends on transparent rules for event definitions, counting and analysis.
The registry record also illustrates why a trial's design description and its results need to be distinguished. Randomization and a parallel-group structure describe how the comparison was organized; they do not, by themselves, provide an estimate of the treatment difference. An interpretable result also requires the outcome data, an analysis method and a measure of uncertainty. The record does not report a single primary-outcome comparison.
Safety information is another part of the statistical picture. Counts of serious events and deaths are meaningful descriptions, but comparative interpretation requires context about ascertainment, denominators, follow-up and analysis. The record lists event counts by group without reporting inferential estimates for them. Treating such counts as proof of a causal effect would go beyond what the posted results establish.
Finally, the registry highlights the value of complete reporting. Clear endpoint definitions, an identified analysis population, missing-data methods, multiplicity plans and effect estimates with uncertainty help readers distinguish exploratory descriptions from confirmatory evidence. These details are not reported in the registry record, leaving important questions about the primary endpoint unanswered.
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 limitation for interpretation is that the registry does not report a single comparison for the stated primary endpoint. The endpoint description spans complication categories and grades, and the record notes that the primary outcome was not reduced to one comparison. No effect estimate, confidence interval, test result or group-specific primary-outcome count is posted.
The record does not report the statistical analysis plan, sample-size justification, analysis population, missing-data handling or multiplicity approach. Without these details, readers cannot assess whether the posted outcomes were analyzed according to a prespecified plan, how incomplete follow-up may have been treated or how multiple categories and secondary outcomes were interpreted.
There is also limited detail about the trial procedures. The record calls the study single-masked but does not identify who was masked. It describes envelope randomization after resection but does not report further details about sequence generation or concealment. The exact relationship between the FloTrac reference in the brief summary and the Edwards EV1000 intervention listing is not explained.
The serious adverse-event summary provides counts by group, but does not report inferential comparisons, event attribution or detailed ascertainment procedures. The listed serious-event percentages are not presented by arm in the summary, and their denominators are not specified there. These limitations prevent the adverse-event information from supporting a precise comparative safety interpretation.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Clinical Trial of Standard Versus Goal-Directed Perioperative Fluid Management (GDT) for Patients Undergoing Liver Resection — NCT01596283.
- Registry record last updated 2017-10-18; status last verified 2016-05.
- Results first posted 2017-10-18.
- 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.
Continue through the Clinical Biostats statistical pathway
Use this trial's endpoint as a starting point for deeper study of effect measures, confidence intervals, and sample-size planning.
18. Record Summary
The registry record describes NCT01596283, a completed Phase 3 randomized, single-masked, parallel-group trial of standard versus goal-directed perioperative fluid management for patients undergoing liver resection. It lists 135 participants enrolled and records the study start as 2012-04 and primary completion as 2016-05.
The primary endpoint was postoperative complications within 30 days after the procedure. The record describes complications as organized by organ system, specific event and grade, but does not provide a single primary-outcome comparison. Secondary outcomes include low cardiac output time, perioperative and postoperative fluid volume, and postoperative length of stay.
The posted serious adverse-event figures include 23 participants among 66 at risk in the standard group and 46 among 69 at risk in the goal-directed group; deaths are listed as 0 and 3, respectively. The registry record does not report an inferential analysis of these figures or the primary endpoint.