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 A Pilot Study of Switching From One Pain Medication to Another (Opioid Rotation) (NCT00580294), a na na study. The primary outcome is Change in Patient Global Impression of Change.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00580294 |
| Phase | NA |
| Condition | Pain |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 12 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Icahn School of Medicine at Mount Sinai |
| Results posted | Yes |
2. Clinical Question
Population
The registry record describes participants with pain who were switching from another pain medication. It lists enrollment as 12. The specific eligibility criteria and participant characteristics are not reported in the registry record, so the population cannot be characterized further from the posted information.
Intervention
Participants switched to oxymorphone extended release, using oral oxymorphone and intravenous patient-controlled analgesia with oxymorphone. After 24 hours, participants were discharged with oral extended-release oxymorphone and immediate-release oxymorphone as needed.
Comparator
There was no separate control group. The registry lists a single-group model and allocation as NA. The prior pain medication is part of the switching context, not a randomized or concurrent comparison arm.
Primary question
The primary outcome was change in Patient Global Impression of Change (PGIC), assessed at baseline and 12 hours. The registry describes the measure as two questions about change in overall status and overall activity. It does not report the numerical mean change or its 95% confidence interval, so the size and precision of the posted primary result cannot be assessed from this record.
3. Trial Design
This completed pilot study examined rapid opioid rotation to oxymorphone. The registry lists the study as a single-group trial with allocation recorded as NA and masking recorded as NONE. There is no concurrent control group, so the design does not support a randomized comparison between oxymorphone and another treatment.
The registry describes participants switching to extended-release oxymorphone through oral administration and intravenous patient-controlled analgesia. After 24 hours, participants were discharged with oral extended-release oxymorphone and immediate-release oxymorphone as needed. The stated purpose was to examine whether switching from another pain medication to oxymorphone could be done over a 24-hour period.
Enrollment is listed as 12. The study phase is recorded as NA. The sponsor is Icahn School of Medicine at Mount Sinai. The registry lists a start date of 2007-11, a primary completion date of 2008-08, and a status of COMPLETED. These record details establish the study setting and design, but do not establish that every enrolled participant completed each assessment.
The primary outcome was a continuous measure summarized as a mean, with a 95% confidence interval specified as its dispersion. The registry gives the outcome timeframe as baseline and 12 hours. The numerical outcome estimate is not reported in the registry record. Details of the analysis population, participant flow, and any methods used to account for repeated measurements are also not reported in the registry record.
Because the study has no control arm, changes over time cannot be separated from other influences using a between-group comparison. The design is useful for describing the planned switching approach and the recorded outcome framework, but it provides limited evidence for attributing an observed change specifically to the intervention.
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 | Oxymorphone |
|---|---|
| STARTED | 12 |
| COMPLETED | 12 |
| NOT COMPLETED | 0 |
5. Baseline Characteristics
The table reproduces the baseline characteristics posted in the registry, which describe the participants analysed at baseline and help show whether the randomized groups were comparable.
| Characteristic | Unit | Oxymorphone |
|---|---|---|
| Participants analysed | 12 | |
| Age, Continuous | years | 50.4 (SD 12.4) |
| Sex: Female, Male: Female | Participants | 10 |
| Sex: Female, Male: Male | Participants | 2 |
| Average Pain Intensity | units on a scale | 7.34 (SD 1.18) |
6. Primary Endpoint
The registry lists the primary outcome as Change in Patient Global Impression of Change, measured over baseline and 12 hours.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | units on a scale |
| Endpoint classification | Continuous Endpoint |
The primary endpoint is change in Patient Global Impression of Change (PGIC), described as a mean measured in units on a scale. The registry says participants answered two questions concerning change from baseline in overall status and overall activity. Each question used a 7-point scale: 1 means very much improved, 2 much improved, 3 minimally improved, 4 no change, 5 minimally worse, 6 much worse, and 7 very much worse.
A patient-reported measure can capture a participant’s own overall view of change, rather than relying only on a clinical or laboratory measure. In this study, that perspective is relevant to the stated question about switching pain medications. The scale’s direction is explicit: lower values correspond to improvement categories, while higher values correspond to worsening categories. However, the registry does not explain how responses to the two questions were combined, or how the change score was calculated.
The timeframe is baseline and 12 hours. The registry specifies a mean and a 95% confidence interval, but the numerical estimate and interval are not reported in the registry record. Without them, the direction, magnitude, and precision of the primary endpoint cannot be evaluated from the posted results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a primary outcome and its intended summary, but it does not report the numerical mean change or 95% confidence interval. It therefore does not establish whether the recorded average change indicated improvement, no change, or worsening, nor how precisely that average was estimated. No p-value or other numerical analysis result is reported in the registry record.
The scale runs from very much improved at 1 to very much worse at 7. This ordering is important when reading any reported change: a lower score is located toward the improvement end of the scale, and a higher score toward the worsening end. The registry does not state the subtraction convention used to calculate change, so the sign of a hypothetical difference should not be inferred without the analysis definition.
A mean can give a compact description of a group’s responses, but it does not show how individual responses were distributed. Participants could have different experiences even when the mean is similar. Also, a 7-point response scale is ordered, but the steps between adjacent response categories are not necessarily perceived as equal. Reporting a mean treats the scale as though averaging its values is informative; that choice can be useful, but it does not replace the underlying response distribution.
A 95% confidence interval, when reported, describes the statistical uncertainty around an estimated mean under the assumptions of the analysis. A narrower interval indicates greater precision for that estimate, while a wider interval indicates more uncertainty. It is not a range that guarantees where an individual participant’s response lies. Because the interval itself is absent, precision cannot be judged.
This was a single-group pilot with no concurrent comparator. Even if a before-and-after change were reported, the design alone would not distinguish a treatment-related change from other explanations, such as changes over time or features of the assessment context. The registry record also does not report an analysis plan or enough detail to assess how repeated observations, missing responses, or the two PGIC questions were handled.
The record lists two outcome measures and no analysis results. The absence of numerical results in the registry record should not be interpreted as evidence that there was no change or that the intervention had no effect. It means the posted information does not permit an estimate of the primary outcome’s direction, size, or precision.
9. Statistical Methods Explained
The primary endpoint is described as a mean of a continuous measure, with a 95% confidence interval. A mean is an average that summarizes the center of a set of recorded values. It can be a useful group-level summary, but it does not describe the range of responses or whether participants’ experiences were similar. Here, the measure is based on ordered response categories. Treating the scores as suitable for a mean assumes that averaging the category values provides a useful summary, even though adjacent categories may not represent equal-sized changes in experience.
What does a confidence interval convey?
In general, a confidence interval expresses uncertainty about an estimated quantity under the assumptions of the statistical method. The estimate is the central summary, and the interval indicates how much uncertainty surrounds it. A confidence interval is not a prediction interval for individual participants, and it does not by itself show whether a result is clinically important. Its interpretation also depends on the analysis being appropriate for the data and study design.
The registry names a 95% confidence interval as the dispersion measure for the primary outcome, but does not report its endpoints. It is therefore not possible to assess the observed precision, or to determine whether the estimate is compatible with a broad range of values. The method used to construct the interval is not reported in the registry record.
How does the single-group design affect interpretation?
In a single-group study, an outcome measured at more than one time can describe change among participants with recorded assessments. A within-participant analysis can account for the fact that measurements from the same person are related. However, the registry does not report whether the primary analysis used paired observations, how it defined change, or whether it adjusted for any other factors.
Without a concurrent control group, a before-and-after difference cannot isolate the effect of the intervention from other influences that may occur over time. A randomized comparison would address a different question by comparing outcomes between assigned groups. This pilot does not have that structure. Thus, even if an estimate were available, it would be a description of change in the study group rather than a controlled estimate of the effect of oxymorphone relative to another treatment.
What does the scale imply for analysis?
The PGIC categories have a clear order from improvement to worsening. The ordering makes it possible to say which response is more favorable in direction, but it does not guarantee equal spacing between response values. A mean can conceal the distribution of responses: the same average could arise from different patterns across participants. Category counts or a distributional summary could add information, but those results are not reported in the registry record.
The endpoint description refers to two questions, one about overall status and one about overall activity. It does not explain whether scores were averaged, combined in another way, or analyzed separately. It also does not specify how a missing response to either question would affect a participant’s endpoint value. These details matter because different scoring choices can produce different summaries.
How should the planning assumptions be read?
The registry describes sample-size calculations as planning illustrations based on an observed effect, rather than as the trial’s own design. The stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is described as a stated fraction of the observed effect. These are assumptions for hypothetical planning calculations, not evidence that this pilot used a two-arm design. The actual trial is listed as single-group.
The numerical observed effect and the planning sample-size values are not reported in the registry record. These illustrations should not be interpreted as observed power or as proof that the study could reliably detect a particular effect. Sample-size calculations depend on their assumptions, including the effect chosen for planning, and do not substitute for reporting the study’s estimate and uncertainty.
For count outcomes, over-dispersion occurs when event counts vary more than a model’s assumptions expect; accounting for it can be important because uncertainty may otherwise be understated. That concept does not directly describe the mean PGIC endpoint. The registry does not report an analysis model for the primary endpoint, so no model-specific assessment can be made.
10. Multiplicity, Missing Data and Analysis Populations
The registry lists two outcome measures, but the details available for interpretation identify the primary endpoint as change in PGIC. The other outcome measure’s definition and analysis are not reported in the registry record. The record does not describe whether additional outcomes were designated as secondary, how multiple outcomes were handled, or whether any adjustment for multiple statistical tests was planned.
Multiplicity matters when several outcomes or comparisons are tested: looking across many results can increase the chance of finding an apparently unusual result by chance. This general concern does not show that a particular result is biased, and it cannot be evaluated for this study without the analysis plan and results. No p-values or outcome estimates are reported in the registry record.
The registry lists enrollment as 12 and the adverse-event risk group as 12, but does not report the number of participants with observed primary endpoint data. It does not provide participant flow, missing-data counts, reasons for missingness, or methods for handling missing observations. It also does not identify an analysis population, such as all enrolled participants or only those with an available assessment.
These omissions limit the ability to assess whether the reported endpoint, if available elsewhere, represents the full enrolled group or a subset. Missingness can affect an estimate when the likelihood of an unavailable response is related to participants’ outcomes or circumstances. The registry record does not provide enough information to characterize that possibility or determine whether a missing-data method was used.
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 |
|---|---|---|---|
| Oxymorphone | 0 | 12 | 0.0% |
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 |
|---|---|
| Oxymorphone | 0 of 12 |
The registry lists 12 participants at risk for serious adverse events in the oxymorphone group and 0 participants affected by serious adverse events. It also lists 12 participants at risk for other adverse events and 0 participants affected. No serious adverse-event terms are listed. The death count is not reported in the registry record.
A zero count means that the registry reports no affected participants in the listed group for that category. It does not establish that the risk is zero, and it does not describe events that may not have been captured or entered in the record. The figures also do not provide information about event severity apart from the serious versus other categorization, timing, duration, or relationship to treatment.
The record does not report the safety observation period or explain how adverse events were collected. Consequently, the counts cannot be interpreted as a complete account of safety over a specified duration. They should be read as the posted event counts for the recorded group, not as a comparison with another treatment, since the study has no control group.
12. What the Result Does, and Does Not, Mean
The registry record describes a pilot of switching participants to oxymorphone, with oral and intravenous patient-controlled administration and discharge treatment after 24 hours. It identifies change in PGIC at baseline and 12 hours as the primary endpoint. These details clarify what the study set out to examine and how the patient-reported outcome was framed.
The record does not report the primary numerical estimate, its 95% confidence interval, or other outcome analysis results. It therefore does not support a conclusion about the average direction or size of change, or how precisely that change was estimated. The missing numerical result is not evidence of no effect; it is an absence of interpretable outcome statistics in the registry record.
The design also limits what can be concluded. With a single group and no concurrent comparator, the study cannot establish whether any change was caused by the switch rather than by other changes over time or circumstances of measurement. A pilot can provide descriptive information about a study approach, but this record does not report enough outcome or implementation detail to assess the experience of participants beyond the listed intervention description.
The serious and other adverse-event summaries each list zero affected participants among 12 at risk. Those counts are a description of the registry entries, not proof of no risk. The death count and safety observation period are not reported in the registry record.
Overall, the posted record establishes the trial’s design, intervention outline, primary measure, and event counts. It does not establish the primary result, its precision, or a comparative treatment effect. Those distinctions are essential when interpreting a completed study whose registry entry lacks numerical efficacy results.
13. Why This Trial Matters Statistically
This trial illustrates how a clearly named endpoint does not by itself make a study result interpretable. The registry describes a patient-reported scale, its response categories, and the planned assessment timeframe. Yet without the mean change and its confidence interval, a reader cannot evaluate the observed direction, magnitude, or precision. Reporting the estimate and uncertainty is central to understanding what the data show.
The study also demonstrates the interpretive limits of a single-group design. Measurements over time may describe participants’ experiences, but a concurrent comparator is needed for a direct between-group contrast. In its absence, causal attribution is limited even if a change estimate is available. That limitation is especially important when a study’s purpose concerns a treatment transition and the record does not include a control arm.
The PGIC scale further illustrates a common measurement issue: ordered categories can be summarized by a mean, but the mean alone may not reveal how responses are distributed. The method used to combine the two questions is not reported in the registry record. Clear scoring rules and response distributions would help readers understand what a group average represents.
Finally, the entry separates planning assumptions from the design actually used. The sample-size calculations are described as planning illustrations involving hypothetical equal allocation between two arms, while the trial itself is listed as single-group. Keeping those concepts distinct prevents a planning calculation from being mistaken for trial design or observed power. Together, these features make the record a useful example of why design, outcome definition, analysis details, and numerical results must be considered separately.
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 important limitation for interpreting outcomes is that numerical primary results are not reported in the registry record. The mean change and 95% confidence interval are absent, as are other outcome estimates and p-values. Without those statistics, the primary endpoint cannot be evaluated for direction, magnitude, or precision.
The trial is listed as single-group, with allocation recorded as NA and masking as NONE. There is no concurrent control group, so the design cannot distinguish a change over time from a change attributable to the intervention. The registry does not report whether participants’ prior medications or clinical characteristics were similar, nor does it provide eligibility criteria or a detailed description of the enrolled population.
The outcome description leaves analysis details unresolved. The registry does not state how the two PGIC questions were combined, how the change score was defined, or how missing responses were handled. It also does not report the analysis population or participant flow. These omissions make it difficult to understand which observations would contribute to the primary estimate.
Safety interpretation is limited by the absence of a reported observation period and the lack of detail on event collection. The death count is not reported in the registry record. The posted zero counts should therefore be read within the limits of the available event summary.
Finally, although the record lists two outcome measures, the additional outcome’s details and the statistical plan are not reported. The registry does not report whether interim analyses or multiplicity procedures were used. No conclusion about those methods can be drawn from the available record.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: A Pilot Study of Switching From One Pain Medication to Another (Opioid Rotation) — NCT00580294.
- Registry record last updated 2016-02-03; status last verified 2016-01.
- Results first posted 2016-02-03.
- 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
NCT00580294 is a completed pilot study of rapid opioid rotation and titration of oxymorphone. The registry lists a single-group design, no masking, and enrollment of 12. Participants switched to oral and intravenous patient-controlled oxymorphone, followed after 24 hours by discharge with oral extended-release oxymorphone and immediate-release oxymorphone as needed.
The primary outcome is change in Patient Global Impression of Change, assessed at baseline and 12 hours and summarized as a mean with a 95% confidence interval. The scale covers very much improved through very much worse. The primary numerical result and its interval are not reported in the registry record. Serious and other adverse-event counts are each listed as 0 affected among 12 at risk; the death count is not reported.