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 Efficient Anterior Shoulder Ultrasound Reduction Multicenter Prospective Randomized Trial (NCT04820491), a randomized na study. The primary outcome is Length of Stay in the Emergency Department (ED).
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT04820491 |
| Phase | NA |
| Condition | Shoulder Dislocation |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 9 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Virginia Commonwealth University |
| Results posted | Yes |
2. Clinical Question
Population
People with shoulder dislocation receiving care in an emergency department. Further eligibility details, such as age range or exclusions, are not reported in the registry record.
Intervention
Ultrasound as a diagnostic test. The study description says ultrasound was intended for diagnosis and confirmation of shoulder-dislocation reductions; the arm description does not provide additional workflow details.
Comparator
X-ray as the diagnostic test. The registry record does not describe the precise imaging sequence or when each test was to be used.
Primary question
Does use of ultrasound, compared with X-ray, affect emergency-department length of stay for this condition? The primary endpoint was defined as time from first provider contact to discharge from the emergency department.
The clinical question concerns an operational outcome: time spent in the emergency department. The study was not described as a comparison of treatments for the dislocation. Its stated purpose was to assess whether the diagnostic approach, including diagnosis and confirmation of reduction, affected the duration of the visit. That distinction matters when interpreting the question: the measured outcome was length of stay, not the success of a particular reduction technique or a patient health outcome.
The record also names patient satisfaction, time to diagnosis, confirmation of reduction, cost of treatment, and total number of X-rays as secondary outcomes. However, it does not report results for these outcomes. Nor does it provide enough detail to determine how the diagnostic approaches were operationalized in practice. With the study terminated and primary-outcome chart data not extracted, the registry record does not answer whether the groups differed in emergency-department length of stay.
3. Trial Design
The EASiUR Trial was recorded as a randomized, parallel-group study with no masking. It compared two diagnostic-test groups: X-ray and ultrasound. The registry lists the condition as shoulder dislocation and identifies Virginia Commonwealth University as the sponsor. The study began on 2021-03-26, and the listed primary completion date is 2021-10-21. Its status is terminated.
Random allocation means that assignment to the study groups was intended to use a chance-based process. The registry record does not report how the random sequence was generated, whether assignment was concealed before enrollment, or how participants were allocated in practice. The parallel model indicates that the groups were distinct rather than a crossover comparison in which each participant received both approaches. The record states that masking was none; it does not describe whether outcome assessors were otherwise separated from knowledge of group assignment.
Enrollment is reported as 9. The record does not report a reason for termination, a detailed recruitment timeline, the number screened or eligible, or whether enrollment reached a planned target. The phase is listed as NA. No sample-size justification or statistical analysis plan is reported in the registry record.
The intervention descriptions contain only the names X-Ray and Ultrasound, and the arm descriptions are blank. The brief study description gives the broad intent of using ultrasound to diagnose and confirm reductions, but details about imaging protocols, clinician training, crossover or rescue testing, and the timing of each procedure are not reported. Those details could affect both the intervention contrast and the interpretation of time spent in the emergency department. As a result, the design can be described at the level of a randomized comparison of diagnostic approaches, but not as a fully specified clinical workflow.
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 | X-Ray | Ultrasound |
|---|---|---|
| STARTED | 5 | 4 |
| COMPLETED | 4 | 4 |
| NOT COMPLETED | 1 | 0 |
Reasons for not completing this period:
| Reason | X-Ray | Ultrasound |
|---|---|---|
| Withdrawal by Subject | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Data was not extracted from patient charts due to termination of the study and in compliance with the HIPAA "Minimum Necessary" standard.
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.
Population: Demographic data was not collected directly from participants but was to be extracted from participant charts. Data was not extracted from patient charts due to termination of the study and in compliance with the HIPAA "Minimum Necessary" standard.
| Characteristic | Unit | X-Ray | Ultrasound | Total |
|---|---|---|---|---|
| Participants analysed | 5 | 4 | 9 | |
| Age, Customized: Unknown | participants | 5 | 4 | 9 |
| Sex/Gender, Customized: Unknown | Participants | 5 | 4 | 9 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | participants | 5 | 4 | 9 |
6. Primary Endpoint
The registry lists the primary outcome as Length of Stay in the Emergency Department (ED), measured over up to 8 hours or time to admission.
| Element | Registry entry |
|---|---|
| Result type | N/A |
| Measure of spread | not applicable |
| Unit | not stated |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint was length of stay in the emergency department. The registry defines it as the interval from the first provider contact to discharge from the emergency department, with the stated timeframe of up to 8 hours or time to admission. The unit, statistical parameter, and measure of dispersion are not reported in the registry record.
Length of stay is an operational endpoint: it describes how long a patient remains in the emergency-department care process. It is relevant to the stated study purpose because diagnostic testing and confirmation procedures may be part of that process. In general, measuring an interval from a defined start point to a defined end point can make workflow duration comparable across study groups, provided that timestamps are collected consistently and the endpoint is handled consistently when admission occurs.
The endpoint does not, by itself, indicate whether a reduction was successful, whether the diagnosis was correct, or whether patients were satisfied. Those topics appear among the named secondary outcomes, but results for them are not reported. Most importantly, the registry says patient-chart data were not extracted for the primary endpoint because the study was terminated and in compliance with the HIPAA “Minimum Necessary” standard. Thus, although the endpoint is defined, no group-level length-of-stay values or comparison are available in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The central interpretive fact is that the registry defines a primary endpoint but does not report analyzed primary-outcome data. It states that chart data were not extracted because the study was terminated and to comply with the HIPAA “Minimum Necessary” standard. The record also lists zero analyses. Consequently, there is no reported group estimate, uncertainty interval, or statistical test for emergency-department length of stay. The posted results do not establish the direction or size of a difference between the X-ray and ultrasound groups.
Enrollment is reported as 9. That enrollment figure describes the study size recorded in the registry; it is not an outcome estimate and cannot substitute for the missing length-of-stay data. The adverse-event groups list 5 people at risk in the X-Ray group and 4 in the Ultrasound group, but those safety counts do not supply the primary endpoint or document the process used to analyze it.
Without an estimate and its uncertainty, readers cannot judge how precisely the study might distinguish between the diagnostic approaches. In general, a confidence interval communicates the range of effect estimates compatible with the data under the analysis assumptions. No confidence interval is reported for the primary endpoint. A p-value is also not reported, and, in any event, a test result alone would not describe the magnitude or precision of an effect.
The registry lists secondary outcomes, including patient satisfaction, time to diagnosis, confirmation of reduction, cost of treatment, and total number of X-rays. Their results are not reported either. The record therefore does not support conclusions about whether the approaches differed on those measures. The absence of posted estimates should not be interpreted as evidence that the approaches were equivalent, nor as evidence that one was better or worse.
The study's randomized designation identifies its intended comparison structure, but randomization does not overcome missing outcome data. The record does not provide the allocation sequence, an analysis population, a statistical model, or details about handling admission and other endpoint circumstances. These omissions prevent assessment of whether a reported comparison would have accounted for the design and endpoint appropriately.
Any planning illustration based on an observed effect must be interpreted as a hypothetical planning exercise, not as an observed trial result or observed power. The registry record does not report a primary-outcome effect estimate from which readers can assess such an illustration. Overall, the available information describes the research question, design, and some safety counts, but it does not provide a statistical answer to the primary question.
9. Statistical Methods Explained
The registry identifies a randomized, parallel-group comparison and lists no analyses. It does not report a statistical analysis plan, a primary-outcome model, or an inferential result. The following concepts explain what such methods would generally mean; they are not a description of analyses performed in this study.
What does randomization contribute?
In general, randomization assigns participants to study groups using chance, with the aim of making the groups comparable in expectation at the time of assignment. It helps protect a comparison from systematic differences in participant characteristics, but it does not guarantee balance in a small study. It also does not ensure that participants receive the assigned approach, that outcomes are collected, or that the analysis follows the planned assignment. The registry identifies randomization but does not report sequence generation, concealment, adherence, or the analysis approach.
How could length of stay be analyzed?
In general, an interval endpoint can be summarized by a measure of central tendency and a measure of variability, then compared between groups using an approach suited to its distribution and the study question. Some methods estimate a difference in mean duration; other methods focus on ranks or time-to-event features. The best choice depends on the data, the endpoint definition, and the analysis plan. Here, the registry gives no unit, parameter, dispersion measure, or analysis method, and it reports no extracted patient-chart data. No particular statistical method can therefore be attributed to the trial.
The endpoint definition ends at discharge from the emergency department, while the timeframe also mentions time to admission. In general, admission can affect how an endpoint is observed and interpreted: the analysis must specify whether admission is an endpoint event, a competing event, or handled in another way. The registry does not report how admission was to be treated analytically. It also does not describe rules for incomplete timestamps, transfers, or other circumstances that might affect measurement.
What does precision mean?
In general, a point estimate is a single numerical summary of a group contrast, while a confidence interval expresses uncertainty around that estimate under the assumptions of the analysis. Wider intervals indicate less precise estimates; narrower intervals indicate greater precision. A confidence interval does not guarantee that the true effect lies within its limits, and it does not correct for biased measurement or missing outcomes. No estimate or confidence interval for length of stay is reported in the registry record.
A p-value, when reported, describes how unusual data at least as inconsistent with a specified null hypothesis would be under the assumptions of a statistical test. It does not measure the probability that the null hypothesis is true, the size of an effect, or its practical importance. No primary-outcome p-value is reported, and no analysis is listed. There is consequently no statistical test to interpret for the primary question.
What is over-dispersion, in general?
For count outcomes, over-dispersion means that observed variability exceeds what a chosen count model assumes. If ignored, the model may understate uncertainty and produce confidence intervals or tests that are too optimistic. Analysts can assess the fit of a model and consider alternatives that allow greater variability. This is a general concept relevant to count outcomes; the record does not report a count-outcome model or an over-dispersion assessment. It should not be confused with the continuous duration endpoint, for which other distributional considerations may be relevant.
How should planning calculations be read?
In general, sample-size calculations describe how much information a proposed study might need under specified assumptions. They are not a measure of what the completed study actually observed. A planning illustration based on an observed effect is especially dependent on that effect estimate and on assumptions about the design and analysis; it is not observed power and should not be treated as evidence that the trial had a particular ability to detect an effect.
The planning assumptions recorded for illustrations are a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect expressed as a stated fraction of the observed effect. For time-to-event calculations, the stated quantity is total events; for other calculations, it is participants per arm. These assumptions describe planning illustrations, not the trial's own design. The record does not report a sample-size justification for the study, and its primary outcome lacks an extracted effect estimate. Without the actual numerical illustrations and the underlying outcome estimate, no specific planning requirement can be interpreted from the registry record.
Finally, a statistical analysis depends on a defined population. An intention-to-treat analysis generally retains participants in their randomized groups, while a per-protocol analysis uses a population defined by adherence criteria. Those choices can answer different questions and may yield different estimates. The registry does not report an analysis population or a rule for handling missing data. With no listed analyses and no extracted primary-outcome chart data, it is not possible to determine which population or method would have been used.
10. Multiplicity, Missing Data and Analysis Populations
The record lists a primary endpoint and secondary outcomes that include patient satisfaction, time to diagnosis, confirmation of reduction, cost of treatment, and total number of X-rays. It also reports 6 outcome measures and 0 analyses. Results for the primary and secondary outcomes are not reported. The registry does not report a multiplicity strategy, such as a prespecified hierarchy of tests or an adjustment to account for testing several outcomes. In general, examining multiple outcomes can increase the chance of at least one apparently unusual result, so a planned interpretation strategy is important. No such strategy is available to assess for this study.
For the primary endpoint, the record explicitly says that data were not extracted from patient charts because of termination and compliance with the HIPAA “Minimum Necessary” standard. The record does not report whether data were collected before termination, how much outcome information was unavailable, or whether any other variables were retained. It gives no missing-data method, imputation procedure, or sensitivity analysis. Therefore, the missingness mechanism and its possible influence on an analysis cannot be evaluated.
The registry also does not report the analysis population, including whether the planned analysis would have followed randomized assignment or restricted the analysis based on treatment received. The participant flow from screening through assignment and follow-up is not reported in the available record. No assumptions about these matters should be inferred from the randomized designation alone. These gaps limit both reproducibility and assessment of possible bias.
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 |
|---|---|---|---|
| X-Ray | 0 | 5 | 0.0% |
| Ultrasound | 0 | 4 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| X-Ray | 0 of 5 |
| Ultrasound | 0 of 4 |
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 |
|---|---|
| X-Ray | 0 of 5 |
| Ultrasound | 0 of 4 |
The registry reports safety counts separately for the X-Ray and Ultrasound groups. In the X-Ray group, 5 were at risk; 0 serious adverse events, 0 other adverse events, and 0 deaths are listed. In the Ultrasound group, 4 were at risk; 0 serious adverse events, 0 other adverse events, and 0 deaths are listed. These are counts in the registry, not estimates of comparative risk.
In general, an adverse-event count depends on who was observed, how long observation lasted, which events were sought, and how events were defined and recorded. The registry record does not describe those surveillance details or provide event terms. The zero counts therefore mean that no events in those categories are listed for the reported groups; they do not establish that no events occurred outside the reported observation or recording process.
The group sizes are limited, and zero events in a small observed group do not precisely determine the frequency of uncommon events in a broader population. No risk difference, confidence interval, or formal safety comparison is reported. These counts should be read as descriptive registry entries, not as proof of safety or as a basis for comparing the diagnostic approaches.
12. What the Result Does, and Does Not, Mean
The registry record establishes that a randomized comparison of X-ray and ultrasound was planned for people with shoulder dislocation, with emergency-department length of stay as the primary endpoint. It also identifies a set of secondary outcomes and reports safety counts. These details clarify the study's intended question and some of its design features.
It does not establish whether ultrasound changed emergency-department length of stay relative to X-ray. The primary outcome data were not extracted from patient charts, and no analyses are listed. There is no reported group estimate, confidence interval, or test result for the primary endpoint. The same lack of reported results applies to the named secondary outcomes. Thus, the record does not show that the approaches were equivalent, nor does it show that one was superior.
In general, a non-significant test, if one existed, would not by itself demonstrate equivalence; equivalence requires a suitable design and a prespecified margin. No equivalence margin or analysis is reported. Likewise, a missing result is not a null result. It represents an absence of an estimate in the registry record, rather than a finding that the groups had identical outcomes.
The posted safety counts list no serious adverse events, other adverse events, or deaths in either group. Those descriptive counts do not answer the primary operational question and cannot establish the absence of risk. The record does not describe safety follow-up in enough detail to draw broader conclusions from the counts.
The most defensible conclusion is limited: this was a terminated randomized study with enrollment reported as 9, and the registry lacks extracted primary-outcome data and analyses. The clinical question remains unanswered by the posted results. Any numerical planning illustration should be understood as a planning exercise under stated assumptions, not as an observed treatment effect or as evidence of observed power.
13. Why This Trial Matters Statistically
This study illustrates an important distinction between a clearly stated research question and an answer supported by outcome data. The registry identifies the population of interest, the two diagnostic approaches, and a time-based primary endpoint. Yet the outcome values needed to estimate a group comparison were not extracted. A well-defined endpoint is necessary for analysis, but its definition cannot replace its measurement.
It also demonstrates why the status and completeness of a registry record matter when interpreting trial statistics. The study is marked terminated, enrollment is reported as 9, and the primary endpoint has no extracted chart data. Without an estimate and an account of its uncertainty, readers cannot judge the magnitude or precision of a possible difference in emergency-department duration. Randomization describes the intended assignment method; it does not create evidence when outcomes are unavailable.
The question itself is statistically useful because it concerns a process measure with a stated start and end point. However, endpoint implementation details, including the handling of admission and the measurement of timestamps, are not reported. Clear operational definitions and analysis rules are particularly important when a study compares diagnostic pathways, because the workflow may determine how the duration is recorded.
The record is also a reminder that zero adverse-event counts and absent efficacy results have different meanings. The safety entries describe observed registry counts in the listed groups, while the primary outcome has no analyzed data. Neither should be stretched beyond what it records. Overall, the study is informative about the intended design and the limits of the available evidence, but not about the comparative statistical result.
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 most consequential limitation is that the primary outcome was not extracted from patient charts. The registry attributes this to termination and compliance with the HIPAA “Minimum Necessary” standard. As a result, no length-of-stay comparison, uncertainty estimate, or analysis is available. The record also reports 0 analyses, so the secondary outcomes do not supply an alternate basis for evaluating the stated question.
Enrollment is reported as 9, but the registry does not explain why the study was terminated or whether recruitment ended before a planned target. A sample-size justification and detailed statistical plan are not reported in the registry record. The record does not provide participant flow, eligibility criteria, baseline characteristics, or group-specific primary-outcome data. It is therefore not possible to assess representativeness, comparability in the enrolled sample, or the extent of missing outcome information.
The intervention descriptions are brief, and the arm descriptions are blank. Details about the diagnostic workflow, timing, training, protocol adherence, and possible use of more than one imaging approach are not reported. The outcome definition names first provider contact and emergency-department discharge, while also specifying a timeframe of up to 8 hours or time to admission; rules for admission and incomplete time measurements are not described.
The record does not report random-sequence generation, allocation concealment, a statistical analysis population, handling of missing data, or a multiplicity strategy. Masking is listed as none, but the record does not specify which study personnel knew assignments or how outcome measurement was conducted. Safety counts are reported without detailed event definitions or follow-up information. These limitations constrain interpretation independently of the missing primary outcome and should prevent conclusions beyond the descriptive details recorded.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Efficient Anterior Shoulder Ultrasound Reduction Multicenter Prospective Randomized Trial — NCT04820491.
- Registry record last updated 2022-11-16; status last verified 2022-10.
- Results first posted 2022-11-16.
- Data retrieved from ClinicalTrials.gov on 2026-11-09.
- Group sizes, means, event counts and sponsor-reported p-values are reproduced as posted. Effect estimates, confidence intervals and p-values not attributed to the sponsor are independently calculated from the posted summary statistics.
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18. Record Summary
The registry record identifies NCT04820491 as the EASiUR Trial, sponsored by Virginia Commonwealth University. It is a randomized, parallel-group study with no masking, comparing X-Ray and Ultrasound for shoulder dislocation. The phase is listed as NA. The study began on 2021-03-26, has a primary completion date of 2021-10-21, and is marked terminated. Enrollment is reported as 9.
The primary endpoint is emergency-department length of stay, defined from first provider contact to discharge, with a timeframe of up to 8 hours or time to admission. Patient-chart data were not extracted for this endpoint, and the registry lists 0 analyses. Secondary outcomes are named, but their results are not reported. Safety entries list no serious adverse events, other adverse events, or deaths in either group. The reason for termination and a detailed analysis plan are not reported in the registry record.