Effect on RLS Symptom Severity After Switching to Neupro® in Patients Who Previously Experienced Augmentation: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Effect on RLS Symptom Severity After Switching to Neupro® in Patients Who Previously Experienced Augmentation (NCT01386944), a registered phase not stated study. The primary outcome is Change From Baseline (Visit 1) in Clinical Global Impression (CGI) (Item 1 - Severity of Illness) to Visit 2.

2. Clinical Question

3. Trial Design

This is a completed, non-interventional observational study sponsored by UCB Pharma. The registry lists an enrollment of 102 and gives the study period as starting 2011-07, with primary completion in 2013-08. The condition is restless legs syndrome. The stated objective focuses on patients with augmentation associated with previous oral dopaminergic therapy who switch to Neupro®.

The treatment description is routine Neupro® treatment at 1,2,3 mg/24 h, as per the approved label in the European Union. The study also set out to evaluate changes in the treatment regimen used when switching, with a secondary outcome covering the period up to 28 days after study entry. The registry does not describe an assigned comparison treatment or a randomized allocation; allocation is not stated. Accordingly, the study is best understood as observation of treatment and outcomes in the described clinical setting, not as a randomized head-to-head trial.

The primary endpoint is the change from baseline, defined as Visit 1, in Clinical Global Impression Item 1, severity of illness, to Visit 2. The record says the rating is made by the treating physician and describes a seven-step severity scale. The primary analysis population is the Full Analysis Set, with inclusion requiring treatment with Neupro at least once, a Visit 1 measurement, and at least one post-Visit 1 measurement on the primary variable.

Although the registry lists an enrollment of 102, it does not report the primary endpoint estimate, its standard deviation, or an interval expressing uncertainty. The enrollment figure should not be treated as the denominator for every outcome: the primary analysis population has its own stated eligibility definition, and the safety results use the denominators reported for those outcomes.

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: The physician was to decide freely to treat the patient with Neupro®. In this context, the physician was not to change routine practice in reaching treatment decisions and in treating his/her patients because of the study. The observational period was 13 months per patient (adjustment period of medication switch plus 12 months of observation).

Overall Study

Reasons for not completing this period:

Analysis population for the primary outcome, as defined in the registry: The Analysis Population refers to the Full Analysis Set (FAS). The FAS is a subset of the Safety Set and consists of all patients who received treatment with Neupro at least once and had a Visit 1 and at least one post-Visit 1 measurement on the primary variable documented.

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: The Baseline Analysis Population refers to the Full Analysis Set (FAS). The FAS is a subset of the Safety Set and consists of all patients who received treatment with Neupro at least once and had a Visit 1 and at least one post-Visit 1 measurement on the primary variable documented.

6. Primary Endpoint

The registry lists the primary outcome as Change From Baseline (Visit 1) in Clinical Global Impression (CGI) (Item 1 - Severity of Illness) to Visit 2, measured over From Baseline up to 7 days.

The primary endpoint is change in the treating physician’s Clinical Global Impression rating of illness severity from Visit 1 to Visit 2. The registry describes the CGI as a global assessment of RLS severity at individual visits. Its seven-step scale ranges from normal, not ill at all, through borderline, mild, moderate, marked, and severe illness, to among the most extremely ill subjects. The record specifies that a negative change from baseline indicates improvement.

A global severity rating can provide a broad clinician assessment rather than measuring only one symptom. It may be useful for describing how the clinician views overall illness severity at a visit. However, the interpretation depends on the scale’s anchors and the judgment of the treating physician. A change score describes movement between two measurements; by itself it does not show which symptoms changed or why they changed.

The endpoint is described as a mean, with standard deviation as its dispersion measure, and its timeframe is from baseline up to 7 days. A mean summarizes the average change, while a standard deviation describes variability among individual changes. These are different quantities: the standard deviation is not a measure of uncertainty in the mean. The numerical mean change and standard deviation are not reported in the registry record, so the magnitude and variability of the observed primary outcome cannot be assessed from the registry entry.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

What does the primary outcome summarize?

The primary outcome is continuous in the registry’s analysis description and is summarized as a mean change. A mean is the arithmetic average of the measured changes in the analysis population. It compresses individual observations into one central summary, so it does not show whether individual patients had similar changes or widely differing changes. The registry specifies standard deviation as the dispersion measure. In general, a standard deviation describes how spread out individual measurements are around their mean; it is not the same as a confidence interval and does not, by itself, quantify precision of the estimated mean.

The CGI item is a seven-step severity rating. Ratings are ordered from less severe to more severe, and the record defines negative change as improvement. The registry nevertheless specifies a mean summary. General statistical caution applies to means for ordered scales: calculating an average treats the differences between successive scale positions as if they can be summarized numerically in a consistent way. The scale anchors help explain the clinical meaning of the positions, but the registry record does not report a separate analysis of the distribution across the individual scale categories.

What does a change score represent?

A change score compares a participant’s post-baseline measurement with the baseline measurement. Here, the comparison is from Visit 1 to Visit 2, with the timeframe stated as from baseline up to 7 days. A mean change describes average movement over that interval. It does not indicate the pattern of measurements between visits, and it cannot by itself distinguish treatment-related change from other time-related or clinical influences.

In general, a confidence interval around a mean change communicates the range of values compatible with the data and analysis assumptions at the chosen confidence level. A narrower interval indicates greater statistical precision than a wider interval, but an interval does not address systematic bias or establish a causal effect. The registry record does not report a confidence interval or the numerical mean and standard deviation for this endpoint.

Why does study design matter?

This is described as a non-interventional observational study. The registry does not state that participants were randomly assigned, and it does not describe a like-for-like control arm. In general, randomization can help balance known and unknown prognostic characteristics across treatment groups. Without a randomized comparison, before-and-after observations may be affected by factors that change over time or differ among patients, including clinical decisions around treatment switching. These are general limitations of interpretation, not claims about what happened to individual participants in this study.

The recorded treatment is routine Neupro® at 1,2,3 mg/24 h according to the approved European Union label. The registry does not report how treatment choices within that description were made or how actual exposure varied. The study’s objective includes changes in treatment regimen, but the results for that secondary outcome are not included in the registry record for interpretation.

How should planning calculations be read?

General sample-size illustrations use assumptions rather than reporting what was observed. The stated illustration assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation, with the target effect defined as a stated fraction of the observed effect. For non-time-to-event outcomes, those illustrations are expressed as participants per arm for 80% power or other stated power levels; time-to-event illustrations use total event counts. The numerical planning values are not reported in the registry record.

These calculations are planning illustrations, not observed power and not evidence that the study was designed with those assumptions. Their equal-allocation, two-arm framework should not be mistaken for the actual design described in the registry, which is non-interventional and does not report a randomized comparator. Because the primary outcome estimate is not reported, no recalculation from its summary statistics can be interpreted. A planning calculation based on an observed effect would not replace the study’s own design information, and the registry record does not report its sample-size justification or statistical plan.

What can adverse-event summaries establish?

Adverse-event counts describe how many participants were recorded with events within the stated risk set. They are not estimates of comparative risk unless a suitable comparison and analysis are available. General interpretation also depends on follow-up duration, event definitions, and ascertainment procedures; these details are not reported in the registry record. A listed event-term percentage should be read as a descriptive registry figure, not as evidence that an event was caused by treatment.

10. Confidence Intervals for Each Arm

No two-arm comparison is shown for this trial, but each arm's mean can be given with a t-based 95% confidence interval computed from the posted mean, spread and number of participants.

R code and output

arm <- c("Neupro® Treatment")
n   <- c(89)
m   <- c(-0.8)
sp  <- c(1.1)
sd  <- sp      # posted standard deviations
for (i in seq_along(n)) {
  se <- sd[i] / sqrt(n[i]); h <- qt(0.975, n[i] - 1) * se
  cat(sprintf("CARM|%s|%d|%.3f|%.3f|%.3f|%.3f\n", arm[i], n[i], m[i], sd[i], m[i] - h, m[i] + h))
}

CARM  Neupro® Treatment  89  -0.800  1.100  -1.032  -0.568

11. Multiplicity, Missing Data and Analysis Populations

The record lists seven outcome measures and six analyses, but does not report how the primary and secondary outcomes were organized into a statistical testing hierarchy. It also does not report whether any adjustment for multiple comparisons was planned. In general, testing many outcomes can increase the chance of obtaining at least one apparently notable result by chance. A prespecified hierarchy or multiplicity adjustment can help address that issue, but neither approach is described in the registry record. Since the primary result itself is not reported, the number of tests that contributed to any conclusion cannot be assessed from this entry.

The registry defines the Full Analysis Set as a subset of the Safety Set comprising patients who received Neupro at least once and had a Visit 1 measurement plus at least one post-Visit 1 measurement on the primary variable. This definition clarifies the eligibility rule for the primary analysis. The number included in that analysis and the number excluded under the rule are not reported in the registry record.

The record does not describe how missing outcome measurements were handled, whether any values were imputed, or whether sensitivity analyses were conducted. In general, missing data can affect a change-score estimate when the availability of follow-up measurements is related to outcome or participant characteristics. An analysis limited to participants with an available post-baseline measure may not represent everyone enrolled if missingness is systematic. The registry’s Full Analysis Set definition alone does not establish that missingness was absent or that its effects were examined.

Allocation is not stated, and the record does not report a statistical analysis plan, interim analyses, or a sample-size justification. Those omissions limit assessment of prespecification and analytic choices. No conclusion about the presence or absence of particular procedures should be inferred where the registry record does not report them.

12. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

Most frequent serious adverse event terms

Most frequent non-serious adverse event terms

Serious events with the highest arm-level rate: colon cancer (2.0%), depression (2.0%), hiatus hernia (1.0%), diverticulum (1.0%), gastrointestinal haemorrhage (1.0%).

The safety results list the Neupro® Treatment group with 99 at risk for serious adverse events and 9 affected. For other adverse events, the listed number at risk is also 99, with 40 affected. These are descriptive counts from the registry record. They are separate from the enrollment figure and from the primary endpoint analysis population; the record does not establish that the denominators for different outcomes represent identical analysis sets.

The listed serious adverse-event terms and percentages are colon cancer, 2.0%; depression, 2.0%; hiatus hernia, 1.0%; diverticulum, 1.0%; gastrointestinal haemorrhage, 1.0%; and acquired oesophageal web, 1.0%. These term percentages should be read as reported, without assuming that they represent mutually exclusive participants or that each event was caused by treatment. The registry record does not provide additional details needed to determine overlap, timing, or clinical context for these terms. A death count is not reported in the registry record.

In general, an adverse-event count describes events recorded under the study’s reporting definitions and follow-up. Without a comparator and fuller information on ascertainment and exposure, these figures do not quantify a treatment-attributable excess or allow a comparative safety conclusion. They should not be treated as a measure of benefit or as proof of causation.

13. What the Result Does, and Does Not, Mean

The record establishes that the study addressed symptom severity and augmentation in patients with RLS who had experienced augmentation associated with previous oral dopaminergic therapy and switched to Neupro®. It defines the primary severity measure, its direction, timeframe, and analysis population rule. It also reports selected adverse-event counts and terms. These details identify what the registry intended to evaluate and provide limited descriptive safety information.

The record does not report a numerical result for the primary change in CGI severity. It therefore does not establish the observed average change, the variability of individual changes, or the precision of an estimate. The definition that a negative change indicates improvement explains how a result would be oriented, but does not itself show that improvement occurred. The record also does not provide enough information to assess the secondary treatment-regimen outcome.

Because the study is non-interventional and does not describe a like-for-like control group, any reported change would need cautious interpretation. A before-and-after pattern would be an observation, not by itself proof that the switch caused it. Differences among participants, concurrent care, and changes over time could contribute to observed outcomes. The registry record does not report analyses that resolve these possibilities.

The adverse-event figures describe recorded events in the stated risk set. They do not establish comparative safety or causation. Likewise, the enrollment figure does not reveal how many participants contributed to the primary analysis; the Full Analysis Set has a separate eligibility definition, and its size is not reported.

In general, a clinical trial registry entry can clarify study intent and selected outcomes, but interpretation depends on complete results and analysis details. Here, the missing primary estimate, uncertainty measure, and information about missing data and multiplicity constrain statistical conclusions. The record supports describing the study design and the results it reports, not claims about effectiveness or treatment choice.

14. Why This Trial Matters Statistically

This study raises a statistical question that is important in practice: how to interpret outcome changes observed after a treatment switch in patients selected because they previously experienced augmentation. The population and clinical context are specific, and the primary outcome is a clinician-rated global severity measure collected at baseline and follow-up. The registry’s definition of a negative change as improvement makes the direction of a possible result explicit.

At the same time, the non-interventional design illustrates why design and endpoint results must be considered together. A change over time can be described, but without a randomized comparator it cannot isolate the effect of switching from other explanations. This distinction between observed change and causal effect is central to interpreting observational clinical data.

The entry also shows why analysis populations matter. Enrollment is reported as 102, while the primary endpoint definition requires treatment exposure and available measurements at specified visits. The analysis denominator is not reported, so the enrollment figure alone cannot establish how much primary outcome information was analyzed. Similarly, safety denominators are outcome-specific and should be read on their own terms.

Finally, the absence of the primary numerical estimate and its uncertainty prevents assessment of magnitude and precision. The study’s objectives and measurement definitions are informative, but they do not substitute for reported results. Statistically, the distinction between a clear question, an observed estimate, its uncertainty, and a causal interpretation remains essential.

15. 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 central limitation for interpreting the primary question is that the registry record does not report the mean change in CGI severity or its standard deviation. The endpoint’s scale, direction, and timeframe are defined, but without the numerical result there is no basis to judge the magnitude or variability of change. No confidence interval is reported for the primary outcome.

The design is non-interventional, and allocation is not stated. The registry does not describe a randomized comparator or a like-for-like control group. Consequently, the record does not support attributing a before-and-after change specifically to the switch. It also does not report details about how treatment decisions or variation in actual treatment exposure were handled.

The primary analysis population is defined by treatment exposure and availability of baseline and post-baseline measurements, but its size is not reported. The registry does not explain missing-data handling or provide sensitivity analyses. It also does not report the statistical analysis plan, sample-size justification, interim analyses, or a multiplicity approach. These gaps limit assessment of whether analysis choices were prespecified and how robust any findings might be.

The primary timeframe is from baseline up to 7 days, while the secondary treatment-regimen outcome covers up to 28 days after study entry. The record does not provide the primary result or the secondary outcome result. For safety, counts and selected serious-event terms are listed, but further details about event timing, follow-up, and ascertainment are not reported in the registry record. These are limitations of what the record allows readers to evaluate; they are not evidence that the underlying study did or did not collect such information.

16. Related Tutorials

17. Related Statistical Calculators

18. Sources

• ClinicalTrials.gov: Effect on RLS Symptom Severity After Switching to Neupro® in Patients Who Previously Experienced Augmentation — NCT01386944.
• Registry record last updated 2018-04-04; status last verified 2018-03.
• Results first posted 2014-08-15.
• 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.

19. Record Summary

This completed, non-interventional observational study examined switching to routine Neupro® treatment in patients with RLS and previous augmentation associated with oral dopaminergic therapy. The registry lists enrollment of 102, a start of 2011-07, and primary completion in 2013-08.

The primary endpoint is mean change from Visit 1 to Visit 2 in the treating physician’s CGI Item 1 severity rating, with a negative change defined as improvement. Its timeframe is from baseline up to 7 days. The Full Analysis Set requires treatment with Neupro at least once and baseline and post-baseline primary measurements.

The primary numerical outcome, its standard deviation, and its confidence interval are not reported in the registry record. The safety results list 9 affected among 99 at risk for serious adverse events and 40 affected among 99 at risk for other adverse events. No randomized comparator is described, so the record supports descriptive interpretation rather than a causal comparison.