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 Nerve Stimulator for Patients With Upper Extremity Disease, Vascular or Orthopedic Surgery (NCT03112642), a randomized na study. The primary outcome is Dermatomes With Complete Motor Block of the Upper Extremities at 30 Minutes.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT03112642 |
| Phase | NA |
| Condition | Other Biomechanical Lesions of Upper Extremity |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 8 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Rutgers, The State University of New Jersey |
| Results posted | Yes |
2. Clinical Question
Population
The trial concerned patients with other biomechanical lesions of the upper extremity undergoing upper-extremity surgery. The registry record lists enrollment as 8. It does not report further participant characteristics, eligibility details, or the types of operations represented.
Intervention
The test group received an ultrasound-guided local anesthetic block at the supraclavicular level, supplemented by a nerve-stimulator device to guide final needle placement. The device is identified as the Braun DIG-R-C Stimuplex Blockade Monitor System. The local anesthetic is listed as 0.35% marcaine.
Comparator
The standard group received the ultrasound-guided supraclavicular block without the added nerve-stimulator guidance described for the test group. The arm description specifies 40 ml of local anesthetic administered after absence of paresthesia and negative aspiration. These details describe the registry entry; further procedural details are not reported in the registry record.
Primary question
The trial asked whether adding nerve stimulation to ultrasound-guided supraclavicular block improves the block outcome for upper-extremity surgery. The primary endpoint was the number of dermatomes with complete motor block at 30 minutes after the block. The record reports arm-level values but no inferential analysis, confidence interval, or estimated treatment contrast. The posted data therefore do not establish the size or precision of a difference between groups.
3. Trial Design
The registry describes a randomized, parallel-group trial with no masking. Participants were assigned to a Standard Group or a Test Group. The trial is listed with phase NA, and the sponsor is Rutgers, The State University of New Jersey. Enrollment is recorded as 8. The registry status is TERMINATED, with primary completion dated 2021-03-09. The start is recorded as 2013-11.
The Standard Group received an ultrasound-guided local anesthetic block at the supraclavicular level. Its description specifies 40 ml of 0.35% marcaine and says administration followed absence of paresthesia and negative aspiration. The Test Group received an ultrasound-guided block supplemented by a nerve-stimulator device to direct final needle placement. The device is identified as the Braun DIG-R-C Stimuplex Blockade Monitor System. The posted Test Group description ends mid-sentence, so further procedural details are not reported in the registry record.
The primary endpoint concerned dermatomes with complete motor block at 30 minutes post block. The endpoint description also refers to assessments of muscle strength at time zero and at 5 minute intervals through the final measurement at 30 minutes, using the MRC power scale. The record does not explain how those repeated assessments were reduced to the arm-level values posted for the primary endpoint.
The registry lists 6 participants in the Standard Group and 2 in the Test Group. It reports arm-level endpoint values of 18.0 and 6.0, respectively. There are no posted analyses for the endpoint or for a two-arm comparison. The record does not report the randomization sequence method, allocation concealment, the rationale for the enrollment target, or an analysis population. These details should not be inferred from the randomized label alone.
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 | Standard Group | Test Group |
|---|---|---|
| STARTED | 6 | 2 |
| COMPLETED | 6 | 2 |
| NOT COMPLETED | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Dermatomes
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 | Standard Group | Test Group | Total |
|---|---|---|---|---|
| Participants analysed | 6 | 2 | 8 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 3 | 2 | 5 |
| Age, Categorical: >=65 years | Participants | 3 | 0 | 3 |
| Age, Continuous | years | 68.3 (SD 12.86) | 61.5 (SD 1.5) | 66.6 (SD 11.55) |
| Sex: Female, Male: Female | Participants | 0 | 1 | 1 |
| Sex: Female, Male: Male | Participants | 6 | 1 | 7 |
| Race and Ethnicity Not Collected | Participants | — | — | 0 |
| Region of Enrollment: United States | participants | 6 | 2 | 8 |
6. Primary Endpoint
The registry lists the primary outcome as Dermatomes With Complete Motor Block of the Upper Extremities at 30 Minutes, measured over 30 minutes post block.
| Element | Registry entry |
|---|---|
| Result type | Count Of Units |
| Measure of spread | not applicable |
| Unit | dermatomes |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “Dermatomes With Complete Motor Block of the Upper Extremities at 30 Minutes.” It is expressed as a count of dermatomes, with the assessment taken 30 minutes after the block. The description says investigators assessed changes in muscle strength in the myotomal distribution corresponding to brachial plexus dermatomes after supraclavicular block. Strength was assessed using the MRC power scale, which the record describes as 0-5, beginning at time zero and continuing at 5 minute intervals until the final assessment at 30 minutes.
In general, a motor-block endpoint can describe whether and how broadly the intended nerve distribution shows the specified motor response after a regional block. A fixed assessment time makes the endpoint refer to a particular point in the procedure rather than combining observations made at different times. It does not, by itself, establish how the block affects pain, surgery, recovery, or other outcomes.
The registry reports arm-level values of 18.0 for the Standard Group and 6.0 for the Test Group. It does not report a measure of spread, a confidence interval, or a statistical comparison. It also does not explain whether these arm-level values are totals, another summary, or how the repeated strength assessments were used to define a complete motor block. That lack of definition limits interpretation of the values as evidence about the primary question.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted results are limited to arm-level endpoint values and safety counts. The Standard Group had 6 participants and an endpoint value of 18.0; the Test Group had 2 participants and an endpoint value of 6.0. The registry reports no spread estimates, confidence intervals, test statistics, or p-values. It lists 0 analyses. Accordingly, the values alone do not quantify an adjusted or unadjusted treatment effect, and no statistical evidence for a group difference is reported.
The endpoint values require particular caution because the registry does not explain their aggregation. The endpoint is described as a count of dermatomes with complete motor block, while the methods description refers to repeated muscle-strength assessments. Without a clear statement of whether the posted values are totals or another summary, it is not possible to determine what participant-level outcome they represent or how the values should be compared. The count endpoint is also not reduced to a single comparison in the posted record.
The small group sizes make the absence of uncertainty estimates especially important. In general, uncertainty estimates describe the range of values reasonably compatible with the data under a specified analysis. Without such an estimate, readers cannot judge how precisely a contrast is estimated. The imbalance in group sizes is part of the reported design and results, but the registry provides no analysis addressing its implications. No new precision estimate can be recovered from the posted summaries because the necessary endpoint definition and statistical information are absent.
The registry status is TERMINATED. That status does not, by itself, explain why the trial ended, whether the planned enrollment was reached, or whether termination was related to the observed results. The reason for termination is not reported in the registry record. The record also does not report a sample-size justification, interim analyses, or a prespecified statistical plan.
The registry lists 0 serious adverse events and 0 other adverse events in the at-risk counts reported for each arm, and 0 deaths in each arm. These observations describe the entries in the registry; they do not establish that an event could not occur or that the groups have equivalent safety. With few participants, absence of a reported event is not a precise estimate of event risk. The record does not provide additional safety analysis or event descriptions.
Overall, the posted results document that endpoint and safety values were entered for both groups, but do not support a reliable estimate of the comparative effect of adding nerve stimulation. The registry does not report secondary outcomes. Conclusions about other outcomes or broader clinical consequences would go beyond the posted data.
9. Statistical Methods Explained
The trial is listed as randomized, unmasked, and parallel-group. Those design labels describe how the registry classifies assignment and study structure; they do not supply missing details about how the study was conducted or analyzed. The method used to generate the randomization sequence and the approach to conceal allocation are not reported in the registry record. Masking is listed as none, so the registry does not describe the trial as blinded.
What does an arm-level value represent?
The primary endpoint is a count of dermatomes with complete motor block at 30 minutes. The posted values are 18.0 for the Standard Group and 6.0 for the Test Group. A count can be summarized in different ways, including as an aggregate across participants or as a participant-level summary, but the record does not specify which interpretation applies to these values. It also gives no measure of variation among participants. As a result, the numbers should not be treated as means, rates, or individual outcomes unless the registry defines them that way.
In general, a comparison of two groups requires a clearly defined outcome for each participant and a method that matches the outcome’s scale and distribution. For a count outcome, the analysis may need to account for skewness or over-dispersion. In general, over-dispersion means that observed variability is greater than a model assumes; ignoring it can make uncertainty estimates misleading. These are general statistical considerations, not claims about an analysis performed in this trial. No endpoint model or inferential method is reported in the registry record.
Why is there no reported treatment contrast?
A treatment contrast expresses how the outcome differs between groups under a defined analysis. The registry lists 0 analyses and indicates that values are missing or not estimable for a two-arm comparison for this count endpoint. It does not report an estimated contrast, standard error, confidence interval, or significance test. The arm-level values alone do not resolve the unspecified endpoint aggregation or provide the information needed to evaluate uncertainty. Consequently, no inferential comparison should be read into the reported values.
In general, a confidence interval gives a range of estimates compatible with the data and assumptions of a statistical procedure. Its width reflects precision: a wider interval indicates greater uncertainty than a narrower one. A confidence interval is not reported for this endpoint. There is therefore no interval-based assessment of the possible size or direction of a group difference in the registry record.
How should planning calculations be interpreted?
In general, a sample-size calculation is a planning exercise based on assumptions about the outcome, target effect, significance level, power, allocation, and analysis method. It does not describe what happened in the trial. A sample-size illustration based on an observed effect is especially dependent on how that effect was defined and estimated. It is not “observed power,” and it cannot compensate for the absence of an interpretable treatment contrast. The registry record does not report the trial’s own sample-size justification. Because a two-arm effect is not estimable from the posted count outcome, the data do not establish a sound observed effect on which to base a trial-specific planning interpretation.
The general assumptions stated for planning illustrations include a two-sided significance level of 0.05, equal allocation, and a normal approximation, with the target effect expressed as a fraction of an observed effect. These are planning assumptions, not evidence that the trial used those methods in its design or analysis. The registry record does not report a set of target fractions or a trial-specific power calculation. Any planning estimate under such assumptions would be hypothetical rather than an observed result.
What do the repeated assessments add?
The endpoint description refers to muscle-strength assessments at time zero and at 5 minute intervals through 30 minutes, with strength recorded on the MRC power scale. Repeated measurements can describe change over time, but their analysis requires a definition of the outcome at each time and a method for handling the correlation of observations from the same participant. In general, measurements from one participant are not independent of one another. The registry record does not report a repeated-measures model or explain how those observations produced the endpoint values posted at the final time point.
No multiplicity adjustment, missing-data method, or analysis population is reported. No secondary outcome analyses are posted. The absence of these details does not establish that no methods were used outside the registry; it means that such methods cannot be assessed from the registry record. Statistical interpretation should therefore remain descriptive and limited to the recorded arm values and safety entries.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists 2 outcome measures, but it reports 0 secondary outcomes posted and 0 analyses. The primary endpoint is identified, but no inferential results are reported for it. A multiplicity strategy—an approach for controlling error when multiple outcomes or comparisons are tested—is not reported in the registry record. Without posted analyses, there is no basis for determining whether any multiplicity adjustment was used or needed in the trial’s analysis.
Missing-data methods and the number of participants with endpoint observations are not reported in the registry record. The listed group sizes are 6 for the Standard Group and 2 for the Test Group, but the record does not say whether all assigned participants contributed endpoint data. It also does not describe exclusions, withdrawals, or how incomplete repeated assessments were handled.
The analysis population is not reported in the registry record. The record does not say whether analyses were intended to follow randomized assignment, include only participants who received the procedure, or use another population definition. In general, the analysis population matters because exclusions after randomization can affect how fairly the assigned groups are compared. No conclusion about the analysis approach can be drawn from the posted arm counts alone.
The registry does not report interim analyses, a prespecified statistical analysis plan, or a sample-size justification. These details should not be inferred from the randomized design or from the fact that the trial is listed as terminated. The reason for termination and any effect of termination on missing observations are also not reported in the registry record.
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 Group | 0 | 6 | 0.0% |
| Test Group | 0 | 2 | 0.0% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Standard Group | 0 of 6 |
| Test Group | 0 of 2 |
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 Group | 0 of 6 |
| Test Group | 0 of 2 |
The registry reports 0 serious adverse events among 6 participants at risk in the Standard Group and 0 among 2 participants at risk in the Test Group. It also reports 0 other adverse events in the at-risk counts for both groups and 0 deaths in both groups. No serious adverse event terms are listed.
These are event counts as entered in the registry, not proof that risk was absent. In general, a zero observed count can occur even when an event remains possible, and a small group provides limited information about how often uncommon events might occur. The record does not provide confidence intervals or another analysis of safety, so the precision of any risk estimate cannot be assessed.
The posted counts also do not establish that safety was equivalent between groups. The groups differ in their listed sizes, and the registry provides no comparative safety analysis. The adverse-event entries should therefore be read descriptively and within the limited enrollment recorded. Additional definitions, monitoring procedures, and details about how adverse events were collected are not reported in the registry record.
12. What the Result Does, and Does Not, Mean
The registry record describes a randomized comparison of a standard ultrasound-guided supraclavicular block and a block supplemented with nerve-stimulator guidance. It reports an endpoint value of 18.0 for the Standard Group and 6.0 for the Test Group, along with group sizes of 6 and 2. Those entries establish what values were posted, but their meaning is constrained by the lack of an explanation of how the arm-level count was formed.
The record does not report a statistical comparison, confidence interval, p-value, or measure of endpoint variability. It therefore does not quantify the uncertainty around a treatment contrast or establish whether the posted values are compatible with a range of possible group differences. The absence of a reported analysis is not evidence of no difference; it is a limit on what can be concluded from the record.
The data also do not answer broader questions about pain relief, recovery, or other clinical outcomes. Although the brief summary frames the study around improved pain relief, the listed primary endpoint concerns complete motor block at 30 minutes. No secondary outcome results are posted. The stated clinical motivation and the measured endpoint should not be treated as interchangeable.
The safety entries record no reported events in the listed at-risk groups, but they do not prove that adverse events cannot occur or that the approaches have equal safety. The trial is small, and the registry does not include a safety comparison or precision estimates.
Thus, the record documents a trial that was terminated and has limited posted results. It does not provide enough statistical detail to make a firm claim about the comparative effect of adding the nerve-stimulator device. The reason for termination, planned sample-size rationale, missing-data handling, and analysis population are not reported in the registry record.
13. Why This Trial Matters Statistically
This trial illustrates why an endpoint needs a clear operational definition as well as an arm-level number. The registry names a count of dermatomes with complete motor block at 30 minutes, while the accompanying description discusses repeated strength assessments over time. Because the record does not explain how those measurements were converted into the posted values, readers cannot confidently identify the statistical quantity being compared.
It also illustrates the distinction between reporting group summaries and estimating a treatment effect. Arm-level values can be recorded without an inferential comparison, but the values alone do not show the precision of a contrast. Here, no variability measure, confidence interval, or analysis is posted. The registry’s indication that a two-arm comparison is not estimable is an important limit on interpretation rather than a reason to reconstruct a comparison from incomplete summaries.
The enrollment and group sizes also matter for statistical interpretation. With 6 participants in the Standard Group and 2 in the Test Group, the record offers little basis for assessing how representative the observed values might be of a wider population. In general, small studies can produce imprecise estimates, and imbalance can further complicate comparisons. These are general considerations; the record does not supply an uncertainty estimate that would quantify them for this trial.
Finally, a terminated trial with no posted analyses demonstrates why registration status and posted results should be read separately. The status does not reveal the reason for stopping, and absence of an analysis does not settle the clinical question. The registry record is useful for identifying the planned comparison and the results entered, while also leaving substantial uncertainty about endpoint construction, analysis methods, and generalizability.
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 principal limitation is the lack of an interpretable statistical comparison. The registry reports arm-level count values but no estimate of the difference, uncertainty measure, or inferential test. It also does not describe the aggregation underlying the count values. This makes it difficult to connect the posted endpoint values to participant-level motor-block outcomes.
The number of participants is limited, with 6 listed in the Standard Group and 2 in the Test Group. The registry does not report whether all enrolled participants had complete endpoint data, how missing observations were handled, or which analysis population was used. The reason for termination is not reported in the registry record, so the consequences of stopping for enrollment or follow-up cannot be assessed.
Further limitations include the absence of a reported sample-size justification, randomization procedure, allocation concealment method, statistical analysis plan, interim-analysis information, and multiplicity approach. The registry does not report secondary outcome results or additional participant characteristics that would help assess the population represented.
The Test Group description ends mid-sentence, leaving some intervention details unavailable in the registry record. The endpoint description refers to serial strength assessments, but does not specify how those assessments define the final count. Together, these omissions limit reproducibility and constrain interpretation of both the endpoint and the comparison.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Nerve Stimulator for Patients With Upper Extremity Disease, Vascular or Orthopedic Surgery — NCT03112642.
- Registry record last updated 2024-03-05; status last verified 2024-03.
- Results first posted 2024-03-05.
- 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 describes a randomized, unmasked, parallel-group trial of ultrasound-guided supraclavicular block with or without added nerve-stimulator guidance for upper-extremity surgery. Enrollment is recorded as 8, and the status is TERMINATED. The primary endpoint is the count of dermatomes with complete motor block at 30 minutes after the block.
The Standard Group has 6 participants and a posted endpoint value of 18.0. The Test Group has 2 participants and a posted value of 6.0. No analyses are reported, and a two-arm comparison is not estimable from the posted count outcome. The registry also records 0 serious adverse events, 0 other adverse events, and 0 deaths in each group.
The registry record does not report the endpoint aggregation method, uncertainty estimates, sample-size justification, analysis population, missing-data approach, or reason for termination. The posted results are therefore descriptive and do not establish the comparative effect of adding nerve stimulation.