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 Low-dose Propofol for the Treatment of Severe Refractory Migraine Headache in the Emergency Department (NCT02492295), a na na study. The primary outcome is Pain Assessed by Numeric Pain Score.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02492295 |
| Phase | NA |
| Condition | Migraine Headache |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 12 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Albert Einstein Healthcare Network |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned people with severe refractory migraine headache in the Emergency Department. The registry record lists migraine headache as the condition and describes a proposed study of refractory migraine. Specific eligibility criteria and further details about the intended population are not reported in the registry record.
Intervention
The intervention was propofol administered intravenously. The registry describes an initial low-dose bolus followed by repeat boluses as needed. It characterizes the study as examining low-dose propofol for refractory migraine in the Emergency Department.
Comparator
No comparator group is listed. The registry record describes a single-group study, with allocation listed as NA and masking listed as none. The design therefore does not set out a randomized or concurrent control comparison.
Primary question
The primary outcome was a numeric pain score assessed 60 minutes after completion of propofol administration. The study question was whether pain was reduced after treatment. The registry record reports that 0 participants were analyzed and that no data were available, so it does not report an outcome estimate that answers this question.
This clinical question is narrower than a comparison of propofol with another treatment: the registry describes an observational study of people receiving propofol, without a listed comparator. Even if pain scores had been reported, a change after treatment in a single group would not by itself separate a treatment-associated change from other explanations, such as the course of symptoms over time or other care. Those are general considerations for interpreting an uncontrolled study, not findings from this registry record.
The registry record does not report the eligibility rules, the numeric pain scale, or a threshold defining a meaningful reduction. It also does not report results for the secondary outcomes. Consequently, the planned question can be described, but the posted record cannot establish the size or precision of any pain reduction or answer whether the intervention differed from another approach.
3. Trial Design
The registry describes a prospective, observational study of low-dose propofol for refractory migraine in the Emergency Department. Its design is listed as single-group, with allocation recorded as NA and masking as none. No comparison arm is listed. Phase is recorded as NA. The study was sponsored by Albert Einstein Healthcare Network.
The registry lists enrollment as 12. That enrollment figure does not indicate how many participants contributed outcome data: the primary outcome entry states that 0 participants were analyzed, explains that the principal investigator had left the institution, and says efforts to make contact were unsuccessful and no data were available. The difference between enrollment and analysis is important; the record does not give participant-level flow or explain whether any enrolled participants completed the study procedures.
The listed start is 2014-08, and the primary completion date is 2016-01-01. The status is terminated. The reason for termination is not reported in the registry record. Nor does the record report whether the planned enrollment was reached, whether recruitment stopped early, or what procedures followed termination.
The brief summary describes the motivation as evaluating propofol in an Emergency Department setting for refractory migraine and identifies pain reduction after treatment as the primary outcome. It also lists several secondary outcomes, including additional rescue medication, willingness to use propofol again, Emergency Room re-admissions, and measures related to sedation. Specific results for these outcomes are not reported in the registry record.
The registry does not report a full statistical analysis plan, sample-size justification for the original study, or details of any interim analyses. The design and outcome information therefore describe the intended evaluation, while the posted results do not provide an analyzed clinical outcome.
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.
Before assignment: 0 Participants analyzed. PI has left the institution. Efforts made to contact were unsuccessful. No data available
Overall Study
| Stage | Propofol |
|---|---|
| STARTED | 0 |
| COMPLETED | 0 |
| NOT COMPLETED | 0 |
Analysis population for the primary outcome, as defined in the registry: 0 Participants analyzed. PI has left the institution. Efforts made to contact were unsuccessful. No data available
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: 0 Participants analyzed. PI has left the institution. Efforts made to contact were unsuccessful. No data available
| Characteristic | Unit | Propofol |
|---|---|---|
| Participants analysed | 0 | |
| Age, Categorical: <=18 years | — | |
| Age, Categorical: Between 18 and 65 years | — | |
| Age, Categorical: >=65 years | — | |
| Sex: Female, Male: Female | — | |
| Sex: Female, Male: Male | — | |
| Region of Enrollment: United States | participants | — |
6. Primary Endpoint
The registry lists the primary outcome as Pain Assessed by Numeric Pain Score, measured over 60 minutes.
| 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 is a numeric pain score assessed 60 minutes after completion of propofol administration. The description also calls this assessment one hour after completion. The record labels the endpoint as pain assessed by Numeric Pain Score and describes reduction of pain after treatment as the primary outcome.
A numeric pain score is a way to represent a participant’s reported pain intensity on a numerical scale. As a general measurement principle, recording pain numerically can make symptom reports easier to summarize and compare across assessments. The meaning of a score depends on the scale used and the way it is collected; the scale, its range, and instructions for participants are not reported in the registry record.
The endpoint description specifies a post-treatment assessment time, but does not state a baseline value, a formal change-score definition, or a threshold for a clinically important change. Those details should not be inferred from the word “reduction.” The registry record reports no analyzed participants and no available data for this endpoint. It therefore gives no post-treatment score, change estimate, measure of variability, or uncertainty interval. The planned measurement is identifiable, but its observed result and precision are not reported.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record does not report a primary outcome result. Although the primary endpoint is identified as a numeric pain score at 60 minutes after propofol administration, the results entry states that 0 participants were analyzed and that no data were available. No group summary, treatment-associated change, confidence interval, or statistical test result is reported. The clinical question therefore remains unanswered by the posted outcome data.
Enrollment is listed as 12, but enrollment is not interchangeable with analysis. The record attributes the absence of data to the principal investigator having left the institution and unsuccessful efforts to contact that investigator. It does not report whether participants had outcome measurements collected before the data became unavailable, nor does it describe any recovery or reconstruction of those data. The enrollment figure cannot be used to infer how many participants had usable pain scores.
The design also limits what a result from the proposed study could establish. This was listed as a single-group observational study, with no comparator group and no masking. In general, an uncontrolled before-and-after observation can describe outcomes over time among people who receive an intervention, but cannot by itself distinguish the intervention’s contribution from other influences. In this record, even such a within-group description is unavailable because no primary outcome data are reported.
The adverse-event entries list 0 at risk and 0 affected for serious and other events. In the context of the record’s explicit statement that no participants were analyzed and no data were available, these entries should not be read as evidence that no adverse events occurred. The registry does not provide an analyzed safety population or event findings that would support that interpretation.
The registry lists secondary outcomes, but does not report their results. It also does not report estimates of precision, such as confidence intervals, for the primary or secondary outcomes. Without outcome observations, there is no basis in the posted record for judging the magnitude, direction, or precision of a treatment-associated change. The record documents a planned evaluation and the absence of usable posted results, rather than evidence for or against an effect.
9. Statistical Methods Explained
The registry classifies the study as prospective and observational, and lists a single-group model. These terms describe the intended structure: participants were to be followed forward in time, and the registry does not identify a randomized allocation or a separate comparator group. Allocation is listed as NA and masking as none. The record does not report more detailed procedures for recruitment, follow-up, or outcome collection.
In a single-group study, an outcome measured after an intervention can describe what happened among participants with available measurements. If measurements at an earlier time are also collected, a change over time may be summarized. These are general analytical possibilities, not claims about analyses completed in this study. The primary endpoint description specifies a numeric pain score after treatment, but the registry record does not report a baseline score or a defined change calculation. It also reports that 0 participants were analyzed and that no data were available. Thus, no within-group estimate can be reconstructed from the posted results.
For a numerical outcome, a statistical summary might include a central estimate and a measure of variation. A confidence interval, in general, communicates a range of values compatible with the data and a specified statistical procedure; it reflects uncertainty in an estimate rather than a range containing a known proportion of individual outcomes. No estimate or confidence interval is reported for the primary endpoint. A p-value, if reported, would address compatibility with a specified statistical model and null hypothesis; it would not by itself convey the size or clinical importance of an effect. The registry record reports no primary-outcome p-value or other test result.
The lack of a comparator is relevant to causal interpretation. In general, a comparison group can help distinguish changes associated with an intervention from changes that might occur without it, although the design and analysis determine how well that distinction is made. Here, the registry lists no control arm and no randomization. Even complete post-treatment measurements would not, on their own, establish what outcomes would have been under an alternative treatment or without propofol. In the posted record, the absence of outcome data further prevents descriptive assessment of the planned endpoint.
The registry lists 12 as enrollment, but the primary outcome entry reports 0 participants analyzed. Those statements refer to different aspects of a study: enrollment describes the registry’s participant count, while analysis requires outcome data available for the relevant analysis. The record does not provide a participant flow accounting, missingness pattern, or outcome availability by participant. It also does not describe any imputation, exclusion rules, or sensitivity analysis. No assumptions about these procedures can be made from the registry entry.
The record includes a planning illustration described as using a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. It states that the effect to detect is a stated fraction of an observed effect, and distinguishes total event counts for time-to-event illustrations from participants per arm for other illustrations. These are planning assumptions, not the study’s reported analysis. They do not change the registry’s single-group design, and they should not be interpreted as observed power. The registry record does not report the original study’s sample-size justification. It also does not report an observed effect estimate in the primary results, so the effect underlying the planning illustration cannot be assessed from the posted results.
For a general planning calculation, the assumed effect and variability determine how much information a study would need to detect a specified difference under the chosen model. If the assumed effect is smaller, more information is generally needed to detect it at the same statistical criteria. Such calculations are prospective illustrations, not evidence that a study achieved a particular probability of detecting an effect after it was conducted. In this case, the planning assumptions describe an equal-allocation, two-arm scenario, whereas the registry design is single-group. The assumptions therefore do not describe a like-for-like analysis of the registered design.
The registry lists multiple secondary outcomes, including additional rescue medications, willingness to use propofol again, Emergency Room re-admissions, and measures related to oxygen saturation, blood pressure, and airway repositioning. In general, testing multiple outcomes raises questions about the interpretation of chance findings and whether any adjustment or prespecified outcome hierarchy was used. The record does not report a multiplicity procedure or a detailed statistical plan. Because no outcome results are reported, multiplicity cannot be assessed empirically for this study.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies a primary pain outcome and lists several secondary outcomes. The secondary outcomes include pain assessed by Numeric Pain Score, additional rescue medications, willingness to use propofol again as assessed by a patient questionnaire, Emergency Room re-admissions, hypoxia defined as SpO2 of <88%, hypotension defined as blood pressure of < 100/60, and the number of patients needing a basic airway repositioning maneuver during sedation. Pain assessed by Numeric Pain Score appears twice in the secondary-outcome list. The record does not explain the repeated entry.
When a study assesses multiple outcomes, a statistical analysis plan may specify which results are primary, how secondary results will be interpreted, and whether methods to address multiplicity will be used. This is a general issue: without such information, a reader cannot determine whether the interpretation accounts for the number of statistical comparisons. A multiplicity adjustment or outcome hierarchy is not reported in the registry record. Nor are outcome-specific estimates or tests available for review.
The record explicitly states that 0 participants were analyzed for the primary endpoint, that the principal investigator had left the institution, that attempts to contact were unsuccessful, and that no data were available. It does not report the amount or pattern of missing outcome data, whether any outcomes were collected but not transferred, or how missing values would have been handled. Imputation, complete-case rules, and sensitivity analyses are not reported in the registry record.
The analysis population is not described beyond the statement that 0 participants were analyzed for the primary outcome. The record does not specify an intention-to-treat population, a per-protocol population, or a safety population with analyzable participant data. The adverse-event entries list zero at risk and zero affected, but the available record does not establish that a safety analysis was conducted. These reporting gaps prevent assessment of outcome completeness and the methods used to address missingness.
11. What the Result Does, and Does Not, Mean
The record establishes what the study intended to examine: low-dose propofol in an Emergency Department setting for severe refractory migraine, with a numeric pain score assessed 60 minutes after administration as the primary endpoint. It also establishes that the registry lists the study as prospective, observational, single-group, and terminated. Those details describe the study and its intended question, not a clinical outcome.
The primary results entry reports 0 participants analyzed and no data available. Consequently, the posted results do not show whether pain scores changed after treatment, how large any change might have been, or how precisely it could be estimated. They also do not provide a basis for judging the listed secondary outcomes. The record cannot support a conclusion that propofol did or did not reduce pain in this study.
The absence of a comparator matters separately from the absence of data. In general, observations from a single group do not offer a direct estimate of what would have happened under another treatment or without the intervention. This study’s registry record does not list a comparison arm. A causal comparison is therefore not available even as a planned contrast in the recorded design.
Similarly, the adverse-event entries should not be taken as proof that no events occurred. They list zero at risk and zero affected, while the primary outcome entry says that no participants were analyzed and no data were available. These entries do not document an observed safety result in a defined, analyzed population.
The planning assumptions included in the record are not observed results and do not resolve these limitations. They are described as illustrations for a two-arm equal-allocation scenario, while the registered design is single-group. No estimate of effect, uncertainty interval, or completed analysis is reported. The most defensible interpretation is that the registry documents a planned clinical question but does not provide outcome evidence with which to answer it.
12. Why This Trial Matters Statistically
This record is statistically important because it illustrates the distinction between a registered study and an analyzable result. The registry lists enrollment as 12, but the primary outcome entry reports 0 participants analyzed and says no data were available. Enrollment alone cannot establish that outcome information was collected, retained, or suitable for analysis. Clear reporting of that distinction is essential when readers assess what a study can contribute.
The record also shows why design information and outcome information need to be read together. The proposed evaluation was prospective and observational, but its model is single-group and no comparator is listed. Even if outcome measurements were available, that design would answer a different question from a controlled comparison. In this case, the absence of data means that the record does not provide even a descriptive estimate of the primary endpoint.
Missing results also constrain statistical interpretation in a direct way. Without participant-level outcomes or a reported summary, there is no estimate to interpret and no uncertainty interval to judge. It is not possible to distinguish a precise null finding from an imprecise estimate, or from an outcome that was never available for analysis. Those situations have different meanings, and the registry record identifies the lack of available data rather than reporting a completed estimate.
Finally, the planning illustration is distinct from evidence generated by the study. It describes assumptions for an equal-allocation, two-arm scenario, while the registered design is single-group. Keeping planning calculations separate from observed results avoids treating a hypothetical design exercise as evidence about participant outcomes. The record’s value is therefore in documenting the intended question, design, and reporting gap, not in quantifying a treatment effect.
13. 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 trial-specific limitation is that the registry reports no analyzed participants and no primary outcome data. The explanation is that the principal investigator had left the institution and efforts to contact that investigator were unsuccessful. The record does not say whether outcome data were collected, whether they were lost, or whether they remain available elsewhere. It gives no results for the secondary outcomes.
The study was registered as a single-group observational study, with no comparator and no masking. That design would limit causal interpretation even if results were available. The registry also does not provide detailed eligibility criteria, the pain scale’s range, a baseline measurement, a definition of pain-score reduction, or a threshold for a meaningful change. These omissions make the planned endpoint less fully specified for external interpretation.
The status is terminated, but the reason for termination is not reported in the registry record. The record does not explain whether recruitment ended as planned or whether the listed enrollment of 12 represents completed recruitment. It also does not give a participant flow account or describe missing-data handling, analysis populations, multiplicity procedures, or a detailed analysis plan.
The adverse-event entries list zero at risk and zero affected, but the record’s statement that no participants were analyzed and no data were available prevents treating these entries as evidence of no harm. The planning illustration describes a two-arm scenario despite the single-group study design and cannot substitute for a study-specific analysis. Together, the unavailable outcomes and design and reporting limits prevent assessment of effectiveness, precision, or safety from this record.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Low-dose Propofol for the Treatment of Severe Refractory Migraine Headache in the Emergency Department — NCT02492295.
- Registry record last updated 2020-03-19; status last verified 2017-05.
- Results first posted 2020-03-19.
- 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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17. Record Summary
The registry record describes a prospective, observational, single-group study of low-dose propofol for severe refractory migraine in the Emergency Department. The primary endpoint was a numeric pain score assessed 60 minutes after completion of propofol administration. Enrollment is listed as 12; the primary outcome entry reports 0 participants analyzed and no data available, citing the principal investigator’s departure from the institution and unsuccessful contact efforts.
The study is listed as terminated, with phase recorded as NA, allocation as NA, and masking as none. No comparator group is listed. The registry reports no primary outcome estimate or secondary-outcome results. The reason for termination, detailed analysis plan, missing-data methods, and multiplicity procedures are not reported in the registry record. The posted information describes the intended evaluation but does not provide an analyzable clinical result.