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 Study in Parkinson's Disease of Exercise (NCT01506479), a randomized na study. The primary outcome is Percentage of Average Maximum Heart Rate During Exercise as a Measure of Adherence to Exercise.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01506479 |
| Phase | NA |
| Condition | Parkinson Disease |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Single |
| Enrollment | 128 |
| Arms in the primary outcome | 2 |
| Lead sponsor | University of Colorado, Denver |
| Results posted | Yes |
2. Clinical Question
Population
People with Parkinson disease were studied, with the primary endpoint description focusing on people with de novo disease who were naïve to drug treatment. The primary endpoint included only participants who contributed heart-rate-monitor data; the registry does not report further details about that analysis population.
Intervention
The exercise arms used endurance exercise at a moderate or vigorous intensity. The prescribed moderate target was 60-65% of maximum heart rate, and the vigorous target was 80-85% of maximum heart rate. Both schedules were described as four times weekly for six months.
Comparator
The study also included a control group that was wait listed for moderate or vigorous exercise after six months of no exercise. The posted primary analysis, however, compares the vigorous and moderate exercise groups, not either exercise group with the control group.
Primary question
Could participants achieve the randomly assigned exercise intensity and adhere to the exercise protocol, as assessed by their average heart rate during exercise? The primary measure was the percentage of average maximum heart rate during exercise from weeks 9 to 26. A separate listed secondary outcome was change in the Unified Parkinson's Disease Rating Scale Motor Score at six months.
This distinction matters when interpreting the result. The primary endpoint evaluates exercise intensity among people with monitor data. It is not a direct measure of Parkinson symptoms, and the reported primary comparison is not a test of exercise against no exercise. The trial’s stated purpose also included learning about exercise effects in recently diagnosed people and exploring different exercise levels, but the primary result presented concerns the achieved intensity in the two exercise groups.
3. Trial Design
The registry describes a randomized, single-masked, parallel study of exercise in people with Parkinson disease. The listed phase is NA. The sponsor was the University of Colorado, Denver. Enrollment was 128, and the record lists the study as completed. The study began in 2012-05, with primary completion in 2016-11.
Three groups were listed: a control group, a moderate exercise group, and a vigorous exercise group. The control group was wait listed to receive moderate or vigorous exercise after six months of no exercise. The exercise programs were endurance exercise four times weekly for six months. The moderate group’s target was 60-65% of maximum heart rate; the vigorous group’s target was 80-85% of maximum heart rate.
The primary endpoint was the percentage of average maximum heart rate during exercise, assessed from weeks 9 to 26. Its stated purpose was to test whether participants could achieve their assigned mean exercise intensity and adhere to the exercise protocol. The primary analysis population was limited to participants who contributed heart-rate-monitor data. The registry reports 38 participants for the vigorous group and 42 for the moderate group for this endpoint. These figures describe the endpoint groups; the record does not explain why they differ from overall enrollment or provide the corresponding primary-endpoint count for the control group.
The posted primary comparison is between vigorous and moderate exercise. The record also lists a secondary outcome, change in the Unified Parkinson's Disease Rating Scale Motor Score at six months. Although three outcome measures and four analyses are listed in the record, additional details about their definitions and analytic roles are not reported in the registry record. Randomization and masking are identified, but the method used to generate the allocation sequence, the party masked, and other implementation details are 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: Screening included confirmation of Parkinson disease diagnosis, assessment of depression and cognition, testing for laboratory measures, and testing for blood pressure and echocardiogram responses to exercise during graded exercise. Once deemed eligible, baseline assessments were completed for disease and non-disease specific scales.
Overall Study
| Stage | Control Group | Vigorous Exercise | Moderate Exercise |
|---|---|---|---|
| STARTED | 40 | 43 | 45 |
| COMPLETED | 37 | 38 | 42 |
| NOT COMPLETED | 3 | 5 | 3 |
Reasons for not completing this period:
| Reason | Control Group | Vigorous Exercise | Moderate Exercise |
|---|---|---|---|
| Lost to Follow-up | 1 | 2 | 2 |
| Withdrawal by Subject | 1 | 2 | 1 |
| Missing assessment | 1 | 0 | 0 |
| Adverse Event | 0 | 1 | 0 |
Analysis population for the primary outcome, as defined in the registry: Only for participants who contributed heart rate monitor data.
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 | Control Group | Vigorous Exercise | Moderate Exercise | Total |
|---|---|---|---|---|---|
| Participants analysed | 40 | 43 | 45 | 128 | |
| Age, Continuous | years | 64 (SD 10) | 64 (SD 9) | 63 (SD 10) | 64 (SD 9) |
| Sex: Female, Male: Female | Participants | 16 | 21 | 18 | 55 |
| Sex: Female, Male: Male | Participants | 24 | 22 | 27 | 73 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 3 | 2 | 6 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 39 | 39 | 41 | 119 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 2 | 3 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 2 | 2 | 2 | 6 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Black or African American | Participants | 2 | 1 | 2 | 5 |
| Race (NIH/OMB): White | Participants | 36 | 39 | 40 | 115 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 1 | 1 | 2 |
| Unified Parkinson Disease Rating Scale Part 3 Motor Evaluation | units on a scale | 17 (SD 7) | 17 (SD 7) | 16 (SD 7) | 17 (SD 7) |
| Total daily steps | steps per day | 5005 (SD 2987) | 5146 (SD 3107) | 5702 (SD 2521) | 5306 (SD 2856) |
| Hoehn and Yahr Stage: Stage 1 | Participants | 8 | 12 | 13 | 33 |
| Hoehn and Yahr Stage: Stage 2 | Participants | 32 | 31 | 32 | 95 |
6. Primary Endpoint
The registry lists the primary outcome as Percentage of Average Maximum Heart Rate During Exercise as a Measure of Adherence to Exercise, measured over 9 to 26 weeks.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | 95% Confidence Interval |
| Unit | percentage of maximum heart rate |
| Endpoint classification | Continuous Endpoint |
The primary endpoint measures average exercise intensity using the percentage of maximum heart rate recorded during exercise. The registry gives a timeframe of weeks 9 to 26 and specifies that only participants who contributed heart-rate-monitor data were included. The endpoint was intended to assess whether people with de novo Parkinson disease, naïve to drug treatment, could reach the mean intensity assigned to them and adhere to the exercise protocol.
In the vigorous group, the mean was 80.3, with a 95% confidence interval from 78.8 to 81.7, among 38 participants. In the moderate group, the mean was 65.9, with a 95% confidence interval from 64.2 to 67.7, among 42 participants. The study’s targets were 80-85% and 60-65% of maximum heart rate, respectively. These results describe measured intensity in the participants with monitor data; they are not a direct measure of symptom change or of adherence for people without monitor data.
This endpoint is useful for interpreting an exercise intervention because a prescribed exercise intensity is meaningful only if participants can attain it during the program. It provides information about the exercise dose achieved in the monitored groups. It does not, on its own, establish whether either exercise program changed Parkinson symptoms. The listed secondary outcome of six-month change in the Unified Parkinson's Disease Rating Scale Motor Score addresses a different question, and the primary result should not be read as a result for that symptom measure.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The posted primary analysis compares final exercise-intensity values for the vigorous and moderate groups. The reported mean difference is 14.3 percentage points of maximum heart rate, with a 95% confidence interval from 12.0 to 16.6 and a two-sided t-test p < 0.001. The group means were 80.3 in the vigorous group and 65.9 in the moderate group. The direction of the reported comparison is consistent with a higher measured average intensity in the vigorous group.
The interval gives a range of values compatible with the observed data under the analysis assumptions and method. It indicates that the reported difference is estimated with greater precision than a much wider interval would indicate, while still allowing uncertainty about the underlying difference. The p-value describes how unusual data at least this inconsistent with a no-difference hypothesis would be if that hypothesis and the test assumptions held. It is not the probability that the no-difference hypothesis is true, nor does it measure the importance of the result.
The statistical result addresses separation in achieved exercise intensity between the two exercise arms. It does not test whether exercise improved symptoms compared with no exercise. The control group is not part of the reported primary comparison, and the listed symptom-related secondary outcome is change in the Unified Parkinson's Disease Rating Scale Motor Score at six months. A result for that secondary endpoint is not included in the reported primary comparison.
The registry reports group means and confidence intervals for people with heart-rate-monitor data, rather than all enrolled participants. The endpoint population is therefore important to the interpretation. The record does not report how many people lacked monitor data, why any data were unavailable, or how missing observations were handled. It also does not report whether the analysis adjusted for other variables or how departures from the planned exercise schedules were treated.
The result is evidence about the measured intensity achieved by these exercise groups over the specified monitoring period. It should not be extended to other outcomes, other populations, or comparisons that were not reported. The primary endpoint’s confidence intervals describe uncertainty in the group means; the separate interval around the reported mean difference describes uncertainty in the contrast. Neither interval supplies evidence about unreported outcomes.
9. Statistical Methods Explained
The registry reports a two-sided t-test comparing final values between the vigorous and moderate exercise groups. The analysis parameter is a mean difference in final values. This is a comparison of average heart-rate intensity, a continuous measure, rather than a comparison of event counts or time until an event.
What does a mean difference describe?
General explanation: a mean is an average, and a mean difference expresses the distance between the averages of two groups on the measure’s scale. In this study, the scale is percentage of maximum heart rate during exercise. The reported mean difference is 14.3, with a 95% confidence interval from 12.0 to 16.6. The registry identifies the contrast as vigorous versus moderate exercise. The difference is a group-level summary and does not describe the experience of every participant.
How should the confidence interval be read?
General explanation: a confidence interval conveys uncertainty in an estimate. A narrower interval indicates more precision than a wider interval, all else equal. A 95% confidence interval is produced by a procedure designed to cover the underlying quantity in 95% of repeated applications under its assumptions. It should not be interpreted as a guarantee about this particular interval. The interval for the reported mean difference gives a range of estimates compatible with the analysis; it does not say that every participant’s intensity fell within that range.
What does the two-sided test contribute?
General explanation: a two-sided test considers departures in either direction from the null hypothesis of no difference. The reported p-value is p < 0.001. Under the null hypothesis and the assumptions of the test, it describes the probability of obtaining a result at least as inconsistent with that hypothesis as the observed result. It does not quantify the probability that the null is true, establish practical importance, or answer a question about symptoms. The registry identifies a t-test but does not report additional details about its assumptions or implementation.
Why does the analysis population matter?
The primary endpoint description limits the population to participants who contributed heart-rate-monitor data. The reported endpoint counts are 38 in the vigorous group and 42 in the moderate group. Conditioning an analysis on available measurements can affect how broadly its result applies, particularly if availability is related to participant characteristics or exercise participation. Whether that occurred is not reported in the registry record. The record also does not report the amount or pattern of missing monitor data, the handling of missing values, or whether an intention-to-treat analysis was used.
What can be said about other statistical choices?
The record identifies randomization, single masking, and a parallel design. It does not report the method of sequence generation, allocation concealment, who was masked, a prespecified statistical analysis plan, model diagnostics, covariate adjustment, or handling of protocol deviations. Those details should not be inferred from the reported t-test. The record lists three outcome measures and four analyses, but does not describe a multiplicity procedure or explain the relationship among all listed analyses. Consequently, the reported p-value should be understood as belonging to the stated comparison, without assuming that it accounts for other outcomes or analyses.
General explanation: over-dispersion is a concern when observed variability exceeds what a statistical model assumes, which can make uncertainty estimates too small if not addressed. That concept is most directly relevant to count or event models; the reported primary endpoint is continuous and analyzed with a t-test. The registry does not report a dispersion assessment, and there is no basis to claim that over-dispersion occurred in this analysis.
Planning calculations based on an observed effect are illustrations of the sample size that might be needed under stated assumptions; they are not the study’s original design justification and are not observed power. The registry record does not report the trial’s sample-size justification or enough information to infer its planning choices. Any planning illustration should therefore be kept separate from the observed comparison and from the trial’s actual enrollment.
10. Analyses Reported by the Sponsor
| Method | Estimate | 95% CI | P-value |
|---|---|---|---|
| t-test, 2 sided | Mean Difference (Final Values) 14.3 | 12.0 to 16.6 | < 0.001 |
The registry reports the sponsor’s comparison as a two-sided t-test of final values, with a mean difference of 14.3 and a 95% confidence interval from 12.0 to 16.6. The reported p-value is p < 0.001. This is the sponsor’s stated inferential result for the primary comparison between vigorous and moderate exercise.
The group-level endpoint summaries are also reported: a mean of 80.3 for vigorous exercise and 65.9 for moderate exercise, with their respective 95% confidence intervals. The sponsor’s comparison is the direct reported test of the difference; the group summaries provide context for that contrast.
No conflicting recalculation is identified in the registry record, so there is no reported discrepancy requiring the sponsor’s result to be set aside in favor of a recalculation. The reported comparison should still be interpreted within its stated scope: final exercise-intensity values among participants contributing heart-rate-monitor data. It is not a test of symptom change or of either exercise group against the control group. Details of any broader adjustment strategy or the full analysis plan are not reported in the registry record.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists three outcome measures and four analyses, but the posted primary comparison is the vigorous-versus-moderate contrast for the percentage of average maximum heart rate during exercise. The record also lists six-month change in the Unified Parkinson's Disease Rating Scale Motor Score as a secondary outcome. It does not explain how all outcomes and analyses relate to one another, identify a hierarchy of hypotheses, or report a multiplicity adjustment. Without those details, the p-value for the primary comparison should be read as the reported test result, not assumed to control the chance of false-positive findings across every outcome or analysis.
The primary endpoint applies only to participants who contributed heart-rate-monitor data. The registry gives endpoint counts for the vigorous and moderate groups, but does not report the number or characteristics of participants without monitor data, reasons for missingness, or methods used to handle missing observations. It also does not say whether all randomized participants were included in the analysis, whether any imputation was used, or whether the analysis followed an intention-to-treat principle. Those analysis-population details are not reported in the registry record.
Randomization is reported, but the record does not give the allocation-generation method, concealment details, or the identity of the masked party. A prespecified statistical analysis plan, interim analyses, sample-size justification, and stopping rules are not reported in the registry record. These absences limit assessment of how the reported comparison relates to planned analyses and how missing observations or multiple comparisons may have been addressed. They do not establish that a particular procedure was or was not used; they mean that the procedure is not documented in the registry record.
12. 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 |
|---|---|---|---|
| Control Group | 0 | 40 | 0.0% |
| Vigorous Exercise | 0 | 43 | 0.0% |
| Moderate Exercise | 2 | 45 | 4.4% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Control Group | 0 of 40 |
| Vigorous Exercise | 0 of 43 |
| Moderate Exercise | 0 of 45 |
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 |
|---|---|
| Control Group | 13 of 40 |
| Vigorous Exercise | 28 of 43 |
| Moderate Exercise | 24 of 45 |
Most frequent serious adverse event terms
| Event term | Organ system | Control Group | Vigorous Exercise | Moderate Exercise |
|---|---|---|---|---|
| Renal calculi | Renal and urinary disorders | 0 of 40 | 0 of 43 | 1 of 45 |
| Gastric ulcer | Gastrointestinal disorders | 0 of 40 | 0 of 43 | 1 of 45 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Control Group | Vigorous Exercise | Moderate Exercise |
|---|---|---|---|---|
| Fall | Injury, poisoning and procedural complications | 9 of 40 | 6 of 43 | 5 of 45 |
| Pain in extremity | Musculoskeletal and connective tissue disorders | 1 of 40 | 8 of 43 | 3 of 45 |
| Upper respiratory infection | Infections and infestations | 1 of 40 | 3 of 43 | 0 of 45 |
| Back pain | Musculoskeletal and connective tissue disorders | 0 of 40 | 4 of 43 | 0 of 45 |
| Surgical and medical procedures - Other, specify | Surgical and medical procedures | 1 of 40 | 0 of 43 | 3 of 45 |
| Flu like symptoms | General disorders | 0 of 40 | 0 of 43 | 3 of 45 |
| Injury, poisoning and procedural complications - Other, specify | Injury, poisoning and procedural complications | 0 of 40 | 0 of 43 | 3 of 45 |
| Cough | Respiratory, thoracic and mediastinal disorders | 1 of 40 | 1 of 43 | 1 of 45 |
| Flu like symptoms | General disorders | 0 of 40 | 2 of 43 | 0 of 45 |
| Urinary tract infection | Infections and infestations | 0 of 40 | 0 of 43 | 2 of 45 |
Serious events with the highest arm-level rate: renal calculi (2.2%), gastric ulcer (2.2%).
The posted safety figures distinguish serious adverse events, other adverse events, and deaths. For serious adverse events, the control group had 0 affected among 40 at risk, the vigorous exercise group had 0 among 43, and the moderate exercise group had 2 among 45. Deaths were reported as 0 in each group. These are counts in the registry record and should be read alongside the stated at-risk group sizes.
Other adverse events were reported for 13 of 40 at risk in the control group, 28 of 43 in the vigorous exercise group, and 24 of 45 in the moderate exercise group. The record lists renal calculi and gastric ulcer among the leading serious-event terms, each at 2.2%. It does not identify an arm for those terms in the information, so they should not be assigned to a particular group on that basis.
These figures are descriptive counts, not a statistical comparison of safety between groups. The registry record does not provide the definitions, event-level timing, duration of follow-up for these safety outcomes, or a formal analysis of between-group differences. Zero reported deaths or zero serious events in a group should not be interpreted as proof that the risk is absent. Nor do the other-event counts establish that the groups differ, because no comparative estimate or uncertainty interval is reported for them.
13. What the Result Does, and Does Not, Mean
The primary result answers a focused statistical question: among participants with heart-rate-monitor data, did the vigorous and moderate groups have different final average exercise intensities? The reported mean difference, confidence interval, and two-sided test indicate a clear separation in measured intensity between these groups in the posted analysis. The result is consistent with the study’s assigned intensity targets being distinguishable in the monitored exercise groups.
It does not establish whether exercise improved Parkinson symptoms, whether either exercise program was better than no exercise for symptoms, or which level of exercise offers the most clinical benefit. The primary endpoint measures heart rate during exercise, not the clinical course of Parkinson disease. Although change in the Unified Parkinson's Disease Rating Scale Motor Score is listed as a secondary outcome, the primary comparison is not a result for that measure.
The comparison also does not describe every participant enrolled in the study. It is limited to the participants contributing heart-rate-monitor data, and the registry does not explain the availability of data for other participants. The estimate is a group average: it does not show that each person in a group reached the target or followed the protocol to the same degree.
Statistical precision and clinical importance are different considerations. A confidence interval communicates uncertainty in the estimated contrast, while the p-value addresses compatibility with a no-difference hypothesis under the test assumptions. Neither alone determines the practical relevance of the measured intensity difference. The record does not provide enough information to infer the effect of the exercise programs on symptoms from this primary endpoint.
The safety counts are also descriptive. They report adverse events and deaths by group but do not supply comparative safety estimates or analyses. Taken together, the posted information supports a narrow interpretation about measured exercise intensity and provides descriptive safety counts; it does not settle broader questions about symptoms, clinical benefit, or comparative safety.
14. Why This Trial Matters Statistically
This study illustrates why the endpoint must be matched to the question being asked. The trial’s stated purpose concerned exercise in people with recently diagnosed Parkinson disease, but the primary reported endpoint is exercise intensity measured through heart-rate monitoring. That endpoint can inform whether the prescribed intensity levels were achieved in the monitored groups. It should not be mistaken for a clinical symptom outcome.
The distinction between the study arms and the reported comparison is also important. A control group was included, but the primary reported test compares vigorous with moderate exercise. The existence of a control arm does not make this particular result a comparison with no exercise. Naming the groups in a result is not enough; interpretation depends on the actual contrast and outcome tested.
The endpoint population provides another statistical lesson. The reported analysis includes only people with monitor data, and its group counts are smaller than overall enrollment. The registry does not explain the missing measurement pattern. Readers therefore need to consider the scope of the observed data without assuming why some measurements are not represented.
Finally, the result demonstrates how an estimate, its confidence interval, and a p-value contribute different information. The mean difference describes the group contrast, the interval conveys uncertainty about that estimate, and the test addresses compatibility with a null hypothesis under its assumptions. None substitutes for the clinical outcome or for analysis-plan details that are not reported in the registry record. Keeping those distinctions explicit supports a disciplined reading of trial results.
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 primary endpoint is based on heart-rate-monitor data, and the record says that only participants who contributed those data were included. The reported group sizes for the endpoint are 38 and 42, while overall enrollment was 128. The registry does not report the reasons for unavailable monitor data, the characteristics of participants without such data, or how missingness was handled. The result may therefore be interpreted directly only for the monitored analysis population described in the record.
The primary comparison is limited to vigorous versus moderate exercise. Although the study included a control group that was wait listed after six months of no exercise, no control-group result for the primary endpoint is reported in the analysis described. The posted primary result consequently cannot be read as an exercise-versus-control comparison.
The endpoint assesses average exercise intensity during weeks 9 to 26. It does not directly assess symptom change, and the record does not provide a result for the listed secondary motor-score outcome in the primary comparison. The available primary analysis therefore has a narrower scope than questions about clinical benefit or symptom change.
The registry identifies a two-sided t-test but does not report its detailed assumptions, diagnostics, adjustment for covariates, or treatment of protocol deviations. It also does not report the analysis plan, multiplicity strategy, sample-size justification, or interim analyses. Such details should not be inferred. The safety results are counts without reported comparative estimates or uncertainty intervals. Together, these limitations constrain conclusions to the reported intensity comparison and descriptive adverse-event information.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Study in Parkinson's Disease of Exercise — NCT01506479.
- Registry record last updated 2017-10-13; status last verified 2017-09.
- Results first posted 2017-10-13.
- 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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19. Record Summary
The registry describes a completed, randomized, single-masked, parallel study of moderate and vigorous endurance exercise in people with Parkinson disease, with a wait-listed control group. Enrollment was 128. The primary endpoint was percentage of average maximum heart rate during exercise from weeks 9 to 26, among participants who contributed monitor data.
The primary reported analysis compared final values in the vigorous and moderate groups using a two-sided t-test. The mean difference was 14.3, with a 95% confidence interval from 12.0 to 16.6 and p < 0.001. This result concerns achieved exercise intensity, not symptom change or comparison with the control group. A six-month change in the Unified Parkinson's Disease Rating Scale Motor Score was listed as a secondary outcome. The registry also reports adverse-event counts and deaths by group, but does not report comparative safety estimates or detailed information about missing data and the broader analysis plan.