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 Efficacy of Orally Disintegrating Selegiline in Parkinson's Patients Experiencing Adverse Effects With Dopamine Agonists (NCT00443872), a na phase 4 study. The primary outcome is Percentage of Participants With Reduction in Adverse Events.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00443872 |
| Phase | Phase 4 |
| Condition | Parkinson's Disease |
| Allocation | Not applicable (single group) |
| Design model | Single Group |
| Masking | None (open label) |
| Enrollment | 77 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Parkinson's Disease and Movement Disorder Center of Boca Raton |
| Results posted | Yes |
2. Clinical Question
Population
People with Parkinson’s disease who were experiencing at least one dopamine-agonist-related adverse effect: excessive daytime sleepiness, hallucinations, pedal edema, or an impulse control disorder. The registry record says 77 patients enrolled and 60 completed. A person could have more than one listed adverse effect.
Intervention
All subjects received orally disintegrating selegiline, also named as Zelapar. The study description specifies adding it while reducing or eliminating the dopamine agonist associated with an adverse effect.
Comparator
There was no separate control group. The registry describes a one-arm, open-label study, with allocation listed as not applicable. The study therefore does not provide a like-for-like comparison with a group continuing dopamine agonist treatment without selegiline.
Primary question
At 3 Months, what percentage of participants had a reduction in daytime sleepiness, hallucinations, pedal edema, or impulse control disorders after a dopamine agonist dose reduction and addition of orally disintegrating selegiline? The outcome description says the record reports reductions for individual adverse effects and for any adverse effect, but those result values are not reported in the registry record.
The clinical question combines two treatment changes: adding selegiline and reducing or eliminating the dopamine agonist associated with the adverse effect. With all subjects receiving selegiline and no comparator group, the study can describe outcomes in this treated group but cannot isolate the contribution of either change or compare the strategy with an alternative. The listed secondary measures concern Parkinson’s symptoms, quality of life, depression, anxiety, and cognition; their results are not reported in the registry record.
3. Trial Design
This was a phase 4, single-group, open-label study of orally disintegrating selegiline in people with Parkinson’s disease experiencing adverse effects associated with dopamine agonists. The registry identifies the intervention as a drug and describes all subjects as receiving orally disintegrating selegiline. The study started in 2007-03, had primary completion in 2008-09, and is marked completed.
The target clinical situation was a dopamine-agonist-related adverse effect: excessive daytime sleepiness, hallucinations, pedal edema, or an impulse control disorder. Participants could have more than one of these effects. The study description states that the dopamine agonist causing an effect was reduced or eliminated while selegiline was added. The primary outcome timeframe was 3 Months.
There was no randomized allocation and no concurrent comparator. The design is therefore not a randomized comparison, and the registry itself cautions that its arms are not a like-for-like control comparison. In practical statistical terms, any reported change would be a change observed in the enrolled group, not an estimated difference between assigned treatment strategies. Because the study was open label, participants and researchers were not masked to treatment; expectations and knowledge of treatment may affect symptom reporting or assessment.
The registry reports 77 enrolled and 60 completed. It lists a single group and does not report a separate control arm. The record lists 10 outcome measures and 10 analyses. It does not report a protocol explanation for the enrollment target, details of how participants were selected beyond the clinical criteria, an interim analysis plan, or a complete statistical analysis plan. The primary outcome description refers to a selected group of 60 subjects but ends with an incomplete sentence, so the selection rationale is not reported in the registry record.
4. Participant Flow and Accounting
The registry reports how participants moved through each stage of the study. All counts below are exactly as posted; missing counts are not inferred from other stages.
Before assignment: Excessive daytime sleepiness was defined by an Epworth Sleepiness Scale (ESS) score greater than 10; pedal edema was bothersome to the subject; hallucinations were bothersome, but insight was maintained; and impulse control disorders (ICDs) included behaviors not requiring immediate medical attention and not harmful to the patient or to others.
Overall Study
| Stage | PD Patients With DA Related AE |
|---|---|
| STARTED | 77 |
| COMPLETED | 60 |
| NOT COMPLETED | 17 |
Reasons for not completing this period:
| Reason | PD Patients With DA Related AE |
|---|---|
| Protocol Violation | 7 |
| Lost to Follow-up | 2 |
| Adverse Event | 8 |
Analysis population for the primary outcome, as defined in the registry: 77 patients enrolled in the study and 60 completed. Each patient had to have at least one of the following DA related AEs, excessive daytime sleepiness, hallucinations, pedal edema or impulse control disorder (they could have more than one AE). 60 subjects were selected based on results of previous studies (discontinued patients were replaced).
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 | PD Patients With DA Related AE |
|---|---|---|
| Participants analysed | 77 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 31 |
| Age, Categorical: >=65 years | Participants | 46 |
| Age, Continuous | years | 66.9 (SD 8.6) |
| Sex: Female, Male: Female | Participants | 38 |
| Sex: Female, Male: Male | Participants | 39 |
| Region of Enrollment: United States | participants | 77 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Participants With Reduction in Adverse Events, measured over 3 Months.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | percentage of participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint is the percentage of participants with a reduction in adverse events at 3 Months. The registry names four individual effects—daytime sleepiness, hallucinations, pedal edema, and impulse control disorders—and says that reductions in individual effects as well as reductions in any adverse effect are reported. The endpoint is intended to capture whether the targeted problems changed after reducing a dopamine agonist dose and adding orally disintegrating selegiline.
A percentage expresses the number meeting an outcome relative to the relevant group denominator. Interpreting it requires knowing how the registry defined a reduction, how participants with more than one effect were counted, and which participants contributed to each result. Those operational details and the primary outcome values are not reported in the registry record. Although the outcome description identifies 77 patients enrolled and 60 who completed, it does not fully explain which denominator was used for each endpoint result.
As a clinical outcome, reduction in a targeted adverse effect is relevant to the study’s stated purpose. It does not, by itself, establish whether Parkinson’s disease symptoms remained controlled. The registry lists UPDRS scores and other measures as secondary outcomes, but their results are not reported in the registry record. Thus, the endpoint addresses changes in the named adverse effects, while the wider balance of adverse-effect reduction and symptom control cannot be assessed from the reported results.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The primary outcome is described, but the registry record does not report the percentages or counts of participants with reductions in the individual adverse effects or in any adverse effect. Consequently, the central result cannot be quantified from this record. No direction or magnitude of change in those primary outcomes should be inferred from the study description alone.
The registry reports 77 patients enrolled and 60 completed. Those figures describe enrollment and completion, not the number with an adverse-effect reduction. The record does not explain the outcome denominator or how missing follow-up measurements were handled. Without those details, even a reported percentage would need to be read alongside its denominator and the handling of participants without endpoint data.
The safety fields are separate from the primary efficacy endpoint. The record lists 77 at risk and 0 affected in the serious adverse event fields, and 77 at risk and 57 affected in the other adverse event fields. These figures do not supply the missing primary outcome results, nor do they establish whether any particular adverse effect improved. The record lists no serious adverse event terms.
Design also limits what a change could mean. This was an open-label, single-group study with no concurrent comparator. Any outcome change would be observed after both the dopamine agonist dose change and addition of selegiline, so the record cannot attribute a change specifically to one component. Without a control group, changes over time could also reflect factors other than the treatment strategy, including the course of symptoms or differences in assessment.
The registry lists UPDRS scores, PDQ-39 quality of life total scores, Beck Depression Inventory, Beck Anxiety Inventory, and MMSE scores as secondary outcomes. Their numerical results are not reported in the registry record. Therefore the available record does not establish how Parkinson’s symptoms, quality of life, mood, anxiety, or cognition changed, or whether those outcomes were consistent with the primary outcome.
Overall, the registry describes the population, treatment strategy, and intended endpoint, but does not provide the primary outcome values needed to judge the observed frequency or precision of adverse-effect reduction. It also does not report confidence intervals or a statistical analysis plan. The statistical interpretation is therefore limited to the design and the reported enrollment, completion, and safety counts, rather than an estimate of treatment effect.
9. Statistical Methods Explained
What does a percentage endpoint convey?
A percentage endpoint describes the fraction of an assessed group meeting a stated condition—in this case, a reduction in a targeted adverse effect. Its interpretation depends on a clearly defined numerator and denominator. The numerator should reflect participants meeting the endpoint definition; the denominator should identify who was eligible for, and included in, that assessment. The registry specifies that the primary outcome concerns percentages with reductions in individual adverse effects and in any adverse effect. It does not report the endpoint values or fully describe the analysis denominator.
In general, a confidence interval describes the range of values compatible with the data under a statistical model, while reflecting sampling uncertainty. A narrow interval indicates greater precision than a wide interval, but neither guarantees that the study design avoids bias. The registry record does not report confidence intervals for the primary outcome, so its precision cannot be assessed from the record.
What can a single-group design estimate?
In a single-group study, outcomes can be described among the participants assessed after treatment. Without a concurrent comparison group, the study does not estimate a randomized between-group contrast. A before-and-after change, if reported, could coincide with the intervention without being caused by it. This is especially relevant because the described strategy combines reducing or eliminating a dopamine agonist with adding orally disintegrating selegiline. The design cannot separate the effect of those components.
Open-label treatment means treatment status is known rather than masked. For outcomes involving symptoms or reported adverse effects, knowledge of treatment can influence reporting, clinical assessment, or both. This is a general design consideration, not evidence that bias occurred in this study. The registry record does not report procedures intended to reduce such influence.
How should the safety counts be read?
The serious adverse event fields list 77 at risk and 0 affected. The other adverse event fields list 77 at risk and 57 affected. These are registry counts, not estimates of a comparison between treatments. A count does not show whether an event was caused by the study intervention, and the record does not provide event descriptions for the other adverse event count. The serious adverse event terms list is empty in the record. These fields should not be substituted for the primary endpoint, which concerns reduction in specified dopamine-agonist-related effects.
What do planning illustrations mean?
Sample-size planning is a forward-looking exercise: it asks how many participants per arm a future study might need under stated assumptions about the effect to detect, significance level, allocation, and statistical approximation. Such an illustration is not an observed result from the present study and is not the study’s achieved power. The registry describes planning assumptions of a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect expressed as a fraction of the observed effect. The record does not report that these assumptions were the original design rationale for this single-group study. Nor does it report the values needed to reconstruct a planning estimate from the primary outcome.
General sample-size calculations depend on assumptions about the outcome, variability or event frequency, effect size, and analysis. If those assumptions differ from reality, the planning estimate may not describe the performance of a future study. For a binary outcome such as whether an adverse effect was reduced, the definition of response and the denominator are particularly important. The registry record does not report a complete statistical plan or a sample-size justification for the trial itself.
What is not established by the record?
The record does not report a primary outcome estimate, its confidence interval, or a p-value. It also does not state the exact statistical model or test used for the listed analyses. These details cannot be inferred from the fact that the record lists 10 outcome measures and 10 analyses. General statistical explanations can clarify what methods would mean, but they cannot fill in missing results or identify an analysis that the registry does not report.
10. Multiplicity, Missing Data and Analysis Populations
The record lists 10 outcome measures and 10 analyses. It names secondary measures including UPDRS scores, PDQ-39 quality of life total scores, Beck Depression Inventory, Beck Anxiety Inventory, and MMSE scores. The primary outcome description also distinguishes individual adverse effects from reduction in any adverse effect. Considering multiple outcomes or analyses raises the general possibility that some results may appear noteworthy by chance, especially if no adjustment or prespecified hierarchy is used. The registry record does not report whether multiplicity was addressed, how outcomes were prioritized, or whether the listed analyses were prespecified.
Missing outcome data also affect interpretation. The record states that 77 patients enrolled and 60 completed, but it does not report the reasons for non-completion, the number assessed for each outcome, or how missing values were handled. It does not state whether analyses included all enrolled participants, only completers, or another analysis population. Therefore the completion figure cannot be treated as the endpoint denominator, and the potential effect of missing data cannot be evaluated.
The record’s primary outcome description says that the participants had to have at least one specified adverse effect and that some could have more than one. It does not explain how multiple effects within one participant were handled in the “any adverse event” result, or how a reduction was defined for each effect. The selection rationale in the description is incomplete. These omissions make it difficult to determine the precise analysis population and how the outcome was constructed.
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 |
|---|---|---|---|
| PD Patients With DA Related AE | 0 | 77 | 0.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 5% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| PD Patients With DA Related AE | 57 of 77 |
Most frequent non-serious adverse event terms
| Event term | Organ system | PD Patients With DA Related AE |
|---|---|---|
| worsening of PD | Nervous system disorders | 13 of 77 |
| Nausea/vomiting | Gastrointestinal disorders | 11 of 77 |
| Dyskinesia | Nervous system disorders | 8 of 77 |
| Increased body aches and pain | General disorders | 6 of 77 |
| Increased insomnia | General disorders | 5 of 77 |
| Increased anxiety | Psychiatric disorders | 4 of 77 |
| Restless legs | Nervous system disorders | 4 of 77 |
| orthostatic hypotension | Cardiac disorders | 4 of 77 |
| Increased depression | Psychiatric disorders | 4 of 77 |
The registry’s serious adverse event fields list 77 at risk and 0 affected. It lists no serious adverse event terms. Its other adverse event fields list 77 at risk and 57 affected. These are the counts recorded in the safety fields; they are not the study’s primary endpoint results.
The registry record does not describe the events underlying the other adverse event count, their severity, timing, duration, or relationship to treatment. It also does not explain how adverse events were collected or whether the counts refer to participants or event episodes beyond the field labels. The absence of listed serious adverse event terms should be read as a feature of the record, not as proof that no safety concerns of any kind occurred. With no comparator, these fields do not estimate whether the treatment strategy changed adverse-event risk relative to another strategy. They also cannot establish that selegiline caused or prevented any event.
12. What the Result Does, and Does Not, Mean
The study addresses a specific clinical situation: people with Parkinson’s disease experiencing one or more dopamine-agonist-related effects, with a strategy of reducing or eliminating the dopamine agonist while adding orally disintegrating selegiline. The registry states that the primary outcome concerns reduction in daytime sleepiness, hallucinations, pedal edema, and impulse control disorders, individually and as any adverse effect, at 3 Months.
The record does not report the primary outcome values. It therefore does not show what percentage of participants had a reduction, how large any change was, or how precisely it was estimated. The registry’s enrollment and completion figures do not answer those questions. Nor can the safety counts be used as a substitute for the missing primary results.
Even if primary outcome changes were available, the single-group open-label design would describe outcomes following a combined treatment strategy rather than establish a causal effect against a control. Because the dopamine agonist was reduced or eliminated while selegiline was added, the design cannot distinguish the contribution of either component. Knowledge of treatment may also affect reporting or assessment of subjective symptoms; the record does not report masking or procedures addressing this issue.
The study’s stated purpose also includes maintaining control of Parkinson’s symptoms. UPDRS scores and other patient-reported or cognitive measures are listed as secondary outcomes, but their results are not reported in the registry record. The record therefore does not establish whether Parkinson’s symptoms or the other measured domains changed alongside the targeted adverse effects.
In short, the record documents the design and intended question but does not provide the outcome data needed to describe the primary result. It cannot support a conclusion about the frequency of adverse-effect reduction, the precision of such a result, or the effect of the treatment strategy compared with an alternative.
13. Why This Trial Matters Statistically
This trial is statistically instructive because its clinical question concerns a treatment strategy, while its design has no concurrent comparator. The intervention is described as adding orally disintegrating selegiline while reducing or eliminating the dopamine agonist associated with an adverse effect. A single-group design can document outcomes among participants receiving that strategy, but it cannot separate changes associated with the strategy from changes that might have occurred over time for other reasons.
The endpoint also illustrates why a percentage needs a transparent denominator and outcome definition. Participants could have more than one target adverse effect, and the primary description refers both to individual effects and to any effect. Interpretation would depend on how reduction was defined, how multiple effects were counted, and who contributed data at 3 Months. The registry does not report these details or the outcome values.
Completion matters for understanding how much outcome data may be available, but the record does not explain missingness or identify the analysis population. A report of enrollment and completion alone cannot show whether missing outcomes were related to participants’ experiences or how those missing data affected estimates.
Finally, this record separates a clearly stated clinical aim from the evidence needed to answer it quantitatively. It describes the treatment strategy, target population, timeframe, and named secondary measures, yet does not report the primary outcome results. Recognizing that distinction prevents design details and safety counts from being mistaken for evidence about the endpoint.
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 main limitation for interpreting efficacy is that the registry record does not report the primary outcome values. The percentage of participants with a reduction in each adverse effect, or in any adverse effect, cannot be assessed, and no confidence intervals or p-values are reported.
The study was open label and single group, with allocation listed as not applicable and no like-for-like control. Any observed change would not establish that the combined strategy caused it. The design also cannot separate changes associated with reducing or eliminating the dopamine agonist from changes associated with adding selegiline.
The record reports 77 enrolled and 60 completed but does not state reasons for non-completion, the denominator used for each outcome, or the approach to missing data. It does not fully define “reduction,” explain how multiple adverse effects in one person were handled, or provide a complete analysis plan. Although it lists 10 outcome measures and 10 analyses, it does not report how multiple analyses were prioritized or addressed.
The primary outcome description ends with an incomplete statement about how 60 subjects were selected. This leaves the selection rationale unclear. Results for the listed secondary outcomes are also not reported in the registry record, limiting assessment of Parkinson’s symptoms, quality of life, mood, anxiety, and cognition. The safety record provides counts but does not describe the other adverse events in detail or establish causality.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Efficacy of Orally Disintegrating Selegiline in Parkinson's Patients Experiencing Adverse Effects With Dopamine Agonists — NCT00443872.
- Registry record last updated 2014-10-31; status last verified 2014-10.
- Results first posted 2014-10-31.
- 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
This completed phase 4 study evaluated orally disintegrating selegiline in people with Parkinson’s disease experiencing dopamine-agonist-related adverse effects. The registry describes a single-group, open-label strategy in which the dopamine agonist associated with an effect was reduced or eliminated as selegiline was added. The primary outcome was the percentage with a reduction in specified effects at 3 Months.
The registry reports 77 enrolled and 60 completed. It lists 10 outcome measures and 10 analyses, including secondary measures of Parkinson’s symptoms, quality of life, depression, anxiety, and cognition. The primary and secondary result values are not reported in the registry record. Serious adverse event fields list 0 affected, and the other adverse event fields list 57 affected; the record provides limited detail about those events. The single-group, open-label design cannot provide a randomized comparison or isolate the effects of the two treatment changes.