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 LIBERATE - LIposomal Bupivacaine vERsus Adjuncts in Total shouldErs (NCT03887650), a randomized phase 4 study. The primary outcome is Total Opioid Consumption.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03887650 |
| Phase | Phase 4 |
| Condition | Post-operative Pain, Total Shoulder Arthroplasty, Osteoarthritis of the Shoulder |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 90 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Hartford Hospital |
| Results posted | Yes |
2. Clinical Question
Population
Patients undergoing primary shoulder arthroplasty were the intended population. The registry lists total shoulder arthroplasty, shoulder osteoarthritis, postoperative pain and pain management among the conditions. The primary outcome description refers to opioid use after total shoulder arthroplasty. The record does not provide further eligibility details in the information reported for this comparison.
Intervention
One arm received a single-injection interscalene brachial plexus block with 10mL liposomal bupivacaine 1.3% (133 mg) mixed with 10mL of 0.5% bupivacaine, for a total volume of 20mL.
Comparator
The comparison arm received a single-injection interscalene block with 20mL of 0.5% bupivacaine, 5 mg PF dexamethasone and 5 mcg epinephrine, for a total volume of 20.5mL. The registry labels this arm bupivacaine 0.5% with adjuncts.
Primary question
The central question was whether total opioid consumption differed between the block regimens. Consumption was standardized to morphine milligram equivalents (MMEs). The primary outcome timeframe is described as up to 120 postoperative hours; the trial summary also describes the primary endpoint as opioid consumption during the first three postoperative days. The registry reports medians and interquartile ranges, with a Wilcoxon (Mann-Whitney) comparison.
This is a comparison of treatment groups in a randomized trial, not a comparison of patients who selected their own block regimen. Random allocation supports a causal interpretation in principle, but the strength of any conclusion also depends on trial conduct, outcome measurement and analysis details. The registry record does not report enough detail to assess all of those features. In particular, it does not report the reasons for withdrawal or the method used to handle missing outcome data.
3. Trial Design
LIBERATE (NCT03887650) is listed as a phase 4, randomized, triple-masked, parallel study sponsored by Hartford Hospital. The record describes it as a single-center, prospective, randomized controlled cross-sectional study comparing interscalene brachial plexus block regimens in patients undergoing primary shoulder arthroplasty. The study status is completed. Its recorded start date is 2019-03-11 and its primary completion date is 2022-01-11.
The planned enrollment was 90. The posted primary outcome groups contain 45 participants for liposomal bupivacaine and 42 for bupivacaine with adjuncts. The primary outcome population description says that 3 patients withdrew from the adjuncts group. The record does not state the reasons for those withdrawals or explain the analysis population in further detail. In particular, it does not specify whether the reported group results follow an intention-to-treat, per-protocol or other population definition.
The intervention was a single injection in the interscalene brachial plexus. The liposomal regimen combined liposomal bupivacaine 1.3% with 0.5% bupivacaine. The comparator used 0.5% bupivacaine with PF dexamethasone and epinephrine. The registry identifies triple masking but does not describe which trial roles were masked or how masking was maintained.
The primary outcome is total opioid consumption standardized to MMEs. Its timeframe is recorded as up to 120 postoperative hours, while the brief summary describes the first three postoperative days. The registry lists 8 secondary outcomes, including time to first opioid medication, pain assessments, hospital length of stay, satisfaction with pain control, block-related numbness distress, sensory block duration, the day of final opioid use and motor recovery. Details of the statistical plan, sample-size justification and any interim analyses 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.
Preoperative-48 Hours Postoperative
| Stage | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| STARTED | 45 | 45 |
| COMPLETED | 45 | 44 |
| NOT COMPLETED | 0 | 1 |
Reasons for not completing this period:
| Reason | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| Withdrawal by Subject | 0 | 1 |
48-96 Hours Postoperative
| Stage | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| STARTED | 45 | 44 |
| COMPLETED | 45 | 42 |
| NOT COMPLETED | 0 | 2 |
Reasons for not completing this period:
| Reason | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| Withdrawal by Subject | 0 | 2 |
60 Postoperative Days
| Stage | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| STARTED | 45 | 42 |
| COMPLETED | 44 | 42 |
| NOT COMPLETED | 1 | 0 |
Reasons for not completing this period:
| Reason | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|
| Withdrawal by Subject | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: 3 patients withdrew from Bupivacaine 0.5% with Adjuncts group.
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 | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts | Total |
|---|---|---|---|---|
| Participants analysed | 45 | 45 | 90 | |
| Age, Continuous | years | 72 (66.5 to 77.0) | 73 (66.5 to 78.0) | 73 (66.75 to 78) |
| Sex: Female, Male: Female | Participants | 22 | 23 | 45 |
| Sex: Female, Male: Male | Participants | 23 | 22 | 45 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 1 | 2 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 44 | 44 | 88 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 0 | 0 |
| 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 | 0 | 2 | 2 |
| Race (NIH/OMB): White | Participants | 44 | 42 | 86 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 1 | 1 | 2 |
| Body Mass Index (BMI) | kg/m^2 | 31.30 (27.25 to 33.65) | 31.60 (27.00 to 35.850) | 31.35 (27.25 to 34.23) |
| ASA Physical Status Classification | units on a scale | 2 (2 to 3) | 2 (2 to 3) | 2 (2 to 3) |
| Preoperative shoulder pain: None | Participants | 12 | 11 | 23 |
| Preoperative shoulder pain: Mild | Participants | 16 | 20 | 36 |
| Preoperative shoulder pain: Moderate | Participants | 15 | 7 | 22 |
| Preoperative shoulder pain: Severe | Participants | 2 | 7 | 9 |
| Comorbidities: Diabetes Miletus : yes | Participants | 6 | 9 | 15 |
| Comorbidities: Diabetes Miletus : no | Participants | 39 | 36 | 75 |
| Comorbidities: Hyperlipidemia : yes | Participants | 26 | 25 | 51 |
| Comorbidities: Hyperlipidemia : no | Participants | 19 | 20 | 39 |
| Comorbidities: Hypertension : yes | Participants | 29 | 25 | 54 |
| Comorbidities: Hypertension : no | Participants | 16 | 20 | 36 |
| Comorbidities: COPD : yes | Participants | 0 | 2 | 2 |
| Comorbidities: COPD : no | Participants | 45 | 43 | 88 |
| Comorbidities: RA : yes | Participants | 0 | 3 | 3 |
| Comorbidities: RA : no | Participants | 45 | 42 | 87 |
6. Primary Endpoint
The registry lists the primary outcome as Total Opioid Consumption, measured over Up to 120 postoperative hours.
| Element | Registry entry |
|---|---|
| Result type | Median |
| Measure of spread | Inter-Quartile Range |
| Unit | MME |
| Endpoint classification | not reduced to a single comparison |
Total opioid consumption measures the amount of opioid medication used after surgery, expressed in morphine milligram equivalents. Standardization to a common unit allows different opioid medications to be represented on a shared scale. The primary outcome description says that the measurement covers total opioid use for the first 120 postoperative hours after total shoulder arthroplasty. The brief summary describes the primary endpoint as total opioid consumption in the first three postoperative days. These descriptions do not state the timeframe in the same way, and the registry record does not explain the difference.
The endpoint is useful for comparing medication use between randomized groups over a defined postoperative period. Unlike a single pain rating, total consumption reflects use across that period, although it does not by itself describe pain intensity, timing of doses, reasons for medication use or individual treatment experiences. The registry separately lists pain assessments and time to first opioid medication as secondary outcomes, but the corresponding results are not included in the primary result information.
The outcome is summarized by its median and interquartile range. A median describes the central observation when values are ordered, while the interquartile range describes the middle portion of the observed distribution. These summaries are useful when outcome values are not well represented by a mean and standard deviation. The registry lists the median for each group and the lower and upper interquartile range limits, but does not report a confidence interval for the difference between groups.
The reported endpoint is therefore a group-level measure of opioid consumption, not a complete account of pain control or recovery. Its interpretation depends on the defined follow-up period, the handling of missing data and how consumption was recorded. Those details are not reported in the registry record beyond the outcome description and the stated withdrawal information.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted median total opioid consumption was 71.25 MMEs in the liposomal bupivacaine group, with an interquartile range of 43.0 to 120.0. In the bupivacaine-with-adjuncts group, the median was 90.3 MMEs, with an interquartile range of 57.37 to 133.4. These summaries describe the distributions in the analyzed groups; they do not give the individual values or show how much the distributions overlap.
The registry reports a Wilcoxon (Mann-Whitney) test with p = 0.127. This is a test of evidence against the null hypothesis under the test's assumptions. A p-value does not give the probability that the null hypothesis is true, nor does it quantify the probability that a particular regimen is better. The record does not state a prespecified significance threshold for this analysis, so the p-value should be read as the reported test result rather than as a standalone decision about the trial's conclusion.
The group medians differ descriptively, but a difference between sample medians is not itself an estimate of the uncertainty around a treatment effect. The registry does not report a confidence interval or a direct estimate of the between-group difference for the primary outcome. A confidence interval, in general, communicates the precision of an estimated effect across values compatible with the data and the model. Without such an interval, the posted summary does not show how precisely the treatment contrast is estimated.
The test is nonparametric and compares the distributions or ranks of observations rather than requiring a normal distribution of the outcome. Its p-value should not be interpreted as a test specifically of the difference between medians unless the relevant distributional assumptions support that interpretation. The registry does not report diagnostic information or further details about the test implementation.
The result applies to the primary outcome as recorded, within its stated postoperative timeframe, and to the analysis population represented by the posted group sizes. The outcome timeframe is described both as up to 120 postoperative hours and as the first three postoperative days. Three patients are reported to have withdrawn from the adjuncts group, which has 42 participants in the primary outcome result. The record does not explain withdrawal reasons or missing-data handling. These features limit assessment of the precision and robustness of the comparison.
Overall, the registry reports the observed group summaries and a Wilcoxon p-value, but not a confidence interval for a treatment contrast, a fully described analysis population or details of the statistical plan. The evidence should be read at that level: as a posted comparison of opioid consumption distributions, with the available precision and analysis details limited by what the registry reports.
9. Statistical Methods Explained
The primary result uses a Wilcoxon (Mann-Whitney) test to compare two independent randomized groups. This rank-based method orders the observed outcomes and evaluates whether values in one group tend to be higher or lower than those in the other. It can be useful when an outcome distribution is skewed or otherwise poorly described by a normal model. It does not require the outcome itself to follow a normal distribution, though interpretation still depends on how the groups and observations are defined and on the test's assumptions.
Why report medians and interquartile ranges?
A median gives the midpoint of the ordered observations. The interquartile range describes the central spread, using its lower and upper limits. These summaries provide information about the typical observed value and variability without relying on a mean as the center of the distribution. They do not, on their own, estimate the uncertainty in the difference between randomized groups. For that purpose, an effect estimate with an uncertainty measure, such as a confidence interval, is commonly helpful. The registry does not report a confidence interval or a direct treatment-effect estimate for this outcome.
The posted summaries are 71.25 MMEs, with interquartile range 43.0 to 120.0, for liposomal bupivacaine, and 90.3 MMEs, with interquartile range 57.37 to 133.4, for bupivacaine with adjuncts. The reported test p-value is 0.127. A p-value describes how compatible the observed data are with a specified null model, under the assumptions of the analysis. It is not a measure of effect size, does not show the precision of an estimate by itself and should not be read as the chance that the null hypothesis is true. The registry record does not report a prespecified threshold for interpreting this test.
What does the test compare?
The Wilcoxon (Mann-Whitney) procedure uses ranks of the observations. In general, if the outcome distributions have similar shapes, a rank-based comparison may be interpreted in relation to a location shift. If shapes differ, the test can reflect broader distributional differences rather than only a median contrast. The registry provides no distribution plots or detailed diagnostic results in the statistical information described for this endpoint. The medians and interquartile ranges alone cannot establish that the two distributions have the same shape.
Randomization determines group assignment, while masking is recorded as triple. In general, randomization can reduce systematic differences between groups at baseline, and masking can limit some sources of biased measurement or care. The registry does not report the allocation procedure, the roles masked or the processes used to maintain masking. Consequently, the design labels alone do not establish how successfully these safeguards were implemented.
What is not documented about the analysis?
The registry reports a primary result and eight secondary outcomes, with 32 analyses recorded overall. It does not report the statistical analysis plan, whether a multiplicity adjustment was used, the prespecified analysis population, the treatment of missing outcomes or whether interim analyses occurred. The sample-size assumptions describe planning illustrations based on a fraction of an observed effect, with a two-sided significance level of 0.05, equal allocation and a normal approximation. Those are described as planning illustrations, not the trial's own design justification. The registry does not report the trial's sample-size justification.
In general, over-dispersion means that observations vary more than a statistical model expects. When a model assumes less variation than is present, standard errors and confidence intervals can be too narrow and tests can be poorly calibrated. That issue is relevant to choosing a model for some outcomes, but the primary comparison is rank-based; the registry does not report an over-dispersion assessment or a model-based analysis for this endpoint. No assumption about over-dispersion should be inferred from the posted medians or p-value.
The record says that three patients withdrew from the adjuncts group and reports 42 participants in that group's primary outcome result. It reports 45 in the liposomal bupivacaine group. In general, missing outcomes can affect both the composition of the analysis population and the comparison, depending on why data are missing and how they are handled. The registry record does not report withdrawal reasons, the missing-data mechanism, an imputation procedure or sensitivity analyses. Thus, the extent to which missing data could influence the result cannot be evaluated from the reported information.
The trial's primary outcome is described using two different postoperative time windows: up to 120 postoperative hours and the first three postoperative days. A clearly defined measurement window matters because total consumption accumulates over time; different windows would represent different outcome definitions. The registry record does not explain whether these descriptions refer to the same operational window. The reported summaries should therefore be understood using the outcome wording attached to the posted result, while recognizing that the registry's descriptions are not fully aligned.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| Wilcoxon (Mann-Whitney) | not reported | 0.127 |
The registry reports the sponsor's primary comparison as a Wilcoxon (Mann-Whitney) analysis with p = 0.127. It does not report a confidence interval or a direct estimate of the between-group effect for this comparison. The posted medians and interquartile ranges describe the groups, but are not a substitute for an uncertainty interval around a treatment contrast.
No discrepancy is flagged between the sponsor analysis and the available recalculation information. The sponsor's reported analysis is therefore the inferential result to cite. A simple recalculation from summary statistics cannot reproduce the original participant-level rank test, because the individual observations and test implementation details are not reported. It should not be presented as a replacement for the sponsor's analysis.
The registry record does not give further details about the analysis plan, the prespecified threshold for interpreting the p-value, or the exact analysis population. Three patients are reported to have withdrawn from the adjuncts group; the primary outcome result lists 42 participants in that group and 45 in the liposomal bupivacaine group. The relation between those withdrawals and the analysis is not described beyond those entries. These limitations do not change the reported p-value, but they constrain independent assessment of how the analysis was carried out.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists 8 secondary outcomes and 32 analyses overall. Multiple outcomes and analyses create a multiplicity issue: when many hypotheses are tested, the chance of finding a low p-value by chance can increase. In general, an analysis plan may specify which result is primary and whether adjustment or other control of multiplicity is intended. The registry record does not report whether multiplicity was addressed, how the 32 analyses relate to the outcomes, or which secondary analyses were considered confirmatory. The primary outcome is identified, but that fact alone does not establish how secondary results should be interpreted.
The record does not report a statistical analysis plan, the sponsor's sample-size justification, an interim-analysis plan or a prespecified significance threshold for the reported Wilcoxon test. The planning assumptions describe illustrations using a two-sided significance level of 0.05, equal allocation and a normal approximation. These assumptions are not evidence that the trial used that threshold for its primary analysis. Sample-size planning illustrations are not observed power and do not establish what the trial was designed to detect.
Missing-data information is limited. The primary outcome population description says that 3 patients withdrew from the bupivacaine-with-adjuncts group. The posted primary outcome results list 45 participants in the liposomal bupivacaine group and 42 in the adjuncts group. Reasons for withdrawal, the timing of withdrawal, the amount of outcome data missing and the approach to missing data are not reported in the registry record. The record also does not identify an intention-to-treat, per-protocol or other analysis population.
In general, analyses that omit participants with missing outcomes can be biased if missingness is related to treatment or to the outcome; other approaches also rely on assumptions. Without details of missingness and the analysis method, the robustness of the result to missing data cannot be assessed. The record does not report sensitivity analyses comparing alternative assumptions about missing outcomes.
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 |
|---|---|---|---|
| Liposomal Bupivacaine 1.3% | 0 | 45 | 0.0% |
| Bupivacaine 0.5% With Adjuncts | 0 | 45 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Liposomal Bupivacaine 1.3% | 0 of 45 |
| Bupivacaine 0.5% With Adjuncts | 0 of 45 |
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 |
|---|---|
| Liposomal Bupivacaine 1.3% | 18 of 45 |
| Bupivacaine 0.5% With Adjuncts | 21 of 45 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Liposomal Bupivacaine 1.3% | Bupivacaine 0.5% With Adjuncts |
|---|---|---|---|
| Nausea and vomiting | General disorders | 8 of 45 | 16 of 45 |
| Bruising | Surgical and medical procedures | 5 of 45 | 3 of 45 |
| Rash | Skin and subcutaneous tissue disorders | 1 of 45 | 1 of 45 |
| Ringing in ears | Ear and labyrinth disorders | 1 of 45 | 1 of 45 |
| Swelling | Surgical and medical procedures | 1 of 45 | 0 of 45 |
| Inflammation | Surgical and medical procedures | 1 of 45 | 0 of 45 |
| Numbness and tingling | Nervous system disorders | 1 of 45 | 0 of 45 |
The registry lists zero serious adverse events in each group, with 45 participants at risk in each group. It also lists zero deaths in each group. The serious-event terms list is empty, so no serious adverse event types are identified in the posted record. These entries describe what was reported to the registry and should not be read as proof that no event of any kind occurred.
The registry separately reports other, non-serious adverse events affecting 18 participants in the liposomal bupivacaine group and 21 in the bupivacaine-with-adjuncts group, with 45 participants at risk in each group. These figures are counts of participants reported as affected, not counts of all event episodes. The information reported does not provide event terms, severity detail, timing or an assessment of whether events were related to a study intervention. No percentages or comparative risk estimates are reported.
Safety figures are not a substitute for the primary opioid-consumption outcome, and the outcome summaries do not establish a safety advantage. The registry record does not give further detail about adverse-event ascertainment or the criteria used to classify events as serious. The figures should therefore be interpreted as the registry's reported event counts, with the available detail limited to the categories and denominators stated.
13. What the Result Does, and Does Not, Mean
The posted result describes opioid consumption after total shoulder arthroplasty in two randomized groups receiving different interscalene block regimens. The median was 71.25 MMEs for liposomal bupivacaine and 90.3 MMEs for bupivacaine with adjuncts. Their interquartile ranges were 43.0 to 120.0 and 57.37 to 133.4, respectively. The registry reports a Wilcoxon (Mann-Whitney) p-value of 0.127. These are descriptive group summaries and a reported statistical test, not a complete estimate of the treatment effect's magnitude and precision.
The available information does not show a confidence interval for a treatment contrast. It therefore does not indicate a range of effect estimates compatible with the data under a specified method. Nor does the p-value state the probability that either regimen is superior, the probability that the null hypothesis is true, or the size of any clinically important difference. The registry record does not report a threshold or a clinical criterion for judging the result.
The primary outcome is opioid use, not a comprehensive measure of pain control, satisfaction, recovery or all potential harms. Pain assessments, time to first opioid medication, satisfaction, length of stay, block numbness, sensory block duration, final opioid-use day and motor recovery are listed as secondary outcomes. The information reported for the primary result does not establish what those secondary outcomes showed.
Interpretation is also constrained by the outcome timeframe descriptions, which refer both to up to 120 postoperative hours and to the first three postoperative days. Three withdrawals are reported in the adjuncts group, but the reasons and handling of missing outcomes are not described. The registry does not give further detail about the masking process or analysis population. These omissions limit assessment of how precisely and robustly the posted comparison represents the intended randomized comparison.
Accordingly, the registry supports describing the observed opioid-consumption summaries and the sponsor-reported test. It does not, on its own, establish the clinical importance of a contrast, resolve uncertainty about missing data or provide a complete comparison of benefits and harms. No treatment recommendation follows from these registry figures alone.
14. Why This Trial Matters Statistically
This trial is statistically informative because it compares two active block regimens using a randomized parallel design and reports an outcome with a skew-resistant summary: the median and interquartile range. Total opioid consumption is a cumulative endpoint, so its definition and follow-up window are important. The record's descriptions of up to 120 postoperative hours and the first three postoperative days are not aligned, illustrating why outcome timing needs to be explicit when interpreting cumulative measurements.
The example also shows why a p-value and a treatment-effect estimate answer different questions. The Wilcoxon (Mann-Whitney) test result is reported as p = 0.127, while no confidence interval or direct estimate of the between-group contrast is reported. A test result alone does not communicate the size or precision of an effect. Reporting both an effect estimate and its uncertainty would make the statistical meaning more complete, but those results are not reported in the registry record.
The group summaries must also be read alongside the analysis population. The planned enrollment was 90; the primary outcome results list 45 participants in one group and 42 in the other, and the record states that 3 patients withdrew from the adjuncts group. Without reasons for withdrawal or the missing-data method, readers cannot determine whether the analyzed groups fully preserve the intended randomized comparison.
Finally, the registry records 32 analyses across the outcome set but does not report how multiplicity was handled. This is a reminder that a primary result sits within a broader family of outcomes and analyses. Clear prespecification, transparent population definitions, explicit missing-data methods and uncertainty intervals help readers distinguish confirmatory evidence from exploratory patterns. The available record does not provide all of those details, so the result is best treated as a limited statistical account of the primary comparison.
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.
Several trial-specific details needed to fully interpret the primary comparison are not reported in the registry record. The primary endpoint timeframe is described as up to 120 postoperative hours, while the brief summary refers to the first three postoperative days. The record does not explain whether these descriptions correspond to the same measurement window. Because opioid consumption accumulates over time, ambiguity about the window limits clarity about the exact endpoint being compared.
The primary outcome population description notes 3 withdrawals from the bupivacaine-with-adjuncts group, and the posted outcome group sizes are 45 and 42. The record does not explain why participants withdrew, when they withdrew, whether any outcome data remained available or how missing data were handled. The analysis population is not identified as intention-to-treat, per-protocol or another defined population. The effect of these omissions on the comparison cannot be assessed from the reported information.
The registry reports medians, interquartile ranges and a Wilcoxon p-value, but not a confidence interval or direct estimate for the between-group treatment effect. It does not describe the analysis plan, a prespecified threshold, multiplicity handling or interim analyses. Although the record identifies triple masking, it does not identify the masked roles or explain how masking was maintained. It also describes the study as single-center but provides no further information in the reported trial details about the setting's representativeness.
Safety reporting is limited to serious events, deaths and other adverse-event counts. Serious event terms are not listed, and the record does not provide event-level detail or describe ascertainment. The secondary outcomes are listed, but their results are not part of the primary outcome information considered in this interpretation. These limitations do not negate the posted result; they define what can and cannot be concluded from the registry record.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: LIBERATE - LIposomal Bupivacaine vERsus Adjuncts in Total shouldErs — NCT03887650.
- Registry record last updated 2023-09-15; status last verified 2023-09.
- Results first posted 2023-09-15.
- 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
LIBERATE (NCT03887650) is a completed phase 4 randomized, triple-masked, parallel study sponsored by Hartford Hospital. It compared two single-injection interscalene brachial plexus block regimens for primary shoulder arthroplasty. Planned enrollment was 90. The recorded start date is 2019-03-11, and the primary completion date is 2022-01-11.
The primary outcome was total opioid consumption standardized to MMEs. The reported medians were 71.25 MMEs for liposomal bupivacaine and 90.3 MMEs for bupivacaine with adjuncts; the registry reports interquartile ranges and a Wilcoxon (Mann-Whitney) p-value of 0.127. The primary outcome result lists 45 and 42 participants, respectively, and notes 3 withdrawals from the adjuncts group.
The registry also lists 8 secondary outcomes and 32 analyses overall. The statistical plan, multiplicity approach, missing-data handling and a confidence interval for the primary treatment contrast are not reported in the registry record.