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 of the Neuro-protective Effect of Granulocyte-colony Stimulating Factor on Early Stage Parkinson's Disease (NCT01227681), a randomized phase 2 study. The primary outcome is Motor Performance of Unified Parkinson's Disease Rating Scale.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT01227681 |
| Phase | Phase 2 |
| Condition | Parkinson Disease |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | Triple |
| Enrollment | 4 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Buddhist Tzu Chi General Hospital |
| Results posted | Yes |
2. Clinical Question
Population
People with early-stage Parkinson disease. The registry record reports enrollment of 4, but does not describe participant characteristics or eligibility details.
Intervention
G-CSF was studied in high-dose and low-dose regimens. The high-dose regimen is listed as 3.3ug/kg/day for consecutive 5 days of each 60 day cycle (6 cycles); the low-dose regimen is listed as 1.65ug/kg/day for consecutive 5 days of each 60 day cycle (6 cycles).
Comparator
The placebo is listed as Sodium Chloride (NaCl) 0.9 %. The registry does not specify which dose regimen or regimens were compared with placebo in the primary-outcome analysis.
Primary question
The stated primary outcome is motor performance measured by Unified Parkinson's Disease Rating Scale (UPDRS) Part III scores in Medication-off status. The registry does not report results by treatment arm, so the size and direction of any treatment-group differences cannot be described.
The study's stated purpose was to evaluate the effectiveness of neuroprotection from granulocyte colony-stimulating factor on Parkinson disease. The primary outcome description focuses on motor function: it specifies comparison of scores from baseline Medication-off status with scores in Medication-off status after G-CSF injection one year. It also gives the endpoint timeframe as 2 years. Those timeline descriptions do not align clearly, and the record does not explain the relationship between them.
The registry identifies G-CSF and placebo as interventions and lists high-dose, low-dose, and placebo arm descriptions. However, the primary-outcome record does not provide arm-level scores or a treatment comparison. It also indicates that the primary outcome could not be represented as a comparison with at least two arms. Consequently, the stated research question can be described, but its answer cannot be evaluated from the posted primary-outcome information.
3. Trial Design
The registry describes a randomized, triple-masked, parallel Phase 2 study sponsored by Buddhist Tzu Chi General Hospital. Its condition is Parkinson Disease. The study start is recorded as 2010-06, and primary completion as 2013-12. Its status is TERMINATED. Enrollment is recorded as 4.
The listed interventions are G-CSF and placebo. The arm descriptions distinguish high-dose G-CSF, low-dose G-CSF, and placebo. The high-dose description specifies 3.3ug/kg/day for consecutive 5 days of each 60 day cycle (6 cycles); the low-dose description specifies 1.65ug/kg/day for consecutive 5 days of each 60 day cycle (6 cycles). The placebo is Sodium Chloride (NaCl) 0.9 %. The record does not report how participants were allocated among these regimens.
Randomization means that assignment is intended to use a chance-based process, which can reduce systematic differences between groups at the point of assignment. The parallel model means participants are assigned to a regimen rather than each participant necessarily receiving every regimen in sequence. Triple masking indicates masking at multiple roles, but the registry information does not identify which roles were masked or explain how masking was maintained. These design labels alone do not establish that allocation or masking proceeded as intended.
The record gives no detailed account of the sequence-generation procedure, allocation concealment, treatment adherence, or reasons for termination. It also does not explain whether termination affected follow-up or outcome collection. The enrollment figure is small as recorded, but the registry does not report whether it reflects the final number treated, the number assessed for the primary outcome, or the number in each arm. These distinctions matter when interpreting an endpoint, and cannot be resolved from the information recorded.
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: No participants were randomized to receive 1.65ug/kg/day of G-CSF and placebo
Overall Study
| Stage | G-CSF | Low Dose G-CSF | Placebo |
|---|---|---|---|
| STARTED | 4 | 0 | 0 |
| COMPLETED | 4 | 0 | 0 |
| NOT COMPLETED | 0 | 0 | 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 | High Dose G-CSF Injection for Parkinson's Disease | Low Dose G-CSF Injection for Parkinson's Disease | Placebo | Total |
|---|---|---|---|---|---|
| Participants analysed | 4 | 0 | 0 | 4 | |
| Age, Categorical: <=18 years | participants | 0 | — | — | 0 |
| Age, Categorical: Between 18 and 65 years | participants | 4 | — | — | 4 |
| Age, Categorical: >=65 years | participants | 0 | — | — | 0 |
| Age, Continuous | years | 49.25 (42 to 56) | — | — | 49.25 (42 to 56) |
| Gender: Female | participants | 0 | — | — | 0 |
| Gender: Male | participants | 4 | — | — | 4 |
| Region of Enrollment: Taiwan | participants | 4 | — | — | 4 |
6. Primary Endpoint
The registry lists the primary outcome as Motor Performance of Unified Parkinson's Disease Rating Scale, measured over 2 years.
| Element | Registry entry |
|---|---|
| Result type | Mean |
| Measure of spread | Full Range |
| Unit | scores on a scale |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is titled “Motor Performance of Unified Parkinson's Disease Rating Scale.” It is described as the Unified Parkinson's Disease Rating Scale Part III, which assesses motor function. Scores range from 0 to 108, with higher values indicating a worse outcome. This direction is essential when interpreting a score difference: a higher score represents worse motor-function status on this scale, not improvement.
The registry specifies a mean parameter and describes dispersion as the full range. A mean is a measure of the central value of a set of scores; the full range describes its lowest and highest observed values. The registry record does not report the mean scores, ranges, or treatment-group contrasts, so these features cannot be used to quantify the outcome in this study.
The stated assessment compares baseline Medication-off status with Medication-off status after G-CSF injection one year. Assessing participants in Medication-off status is part of the endpoint definition as recorded; the record does not provide further operational details about that status or the timing of assessments. The endpoint timeframe is separately listed as 2 years, leaving the timing unclear. The registry does not explain whether that timeframe refers to follow-up, treatment, or another aspect of assessment.
Motor function is relevant to the study's stated question because the purpose concerns Parkinson disease and the endpoint explicitly measures motor performance. But an endpoint's relevance does not substitute for results. Without reported scores and a defined comparison, the registry does not establish whether groups differed or how precisely any difference was estimated.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record identifies a primary motor-function outcome, but does not report its results by treatment arm. There are no posted primary-outcome means, full ranges, or estimates of a contrast between G-CSF and placebo. The direction and size of any difference, and the uncertainty around it, are therefore not reported in the registry record. No conclusion about the primary outcome can be drawn from the endpoint description alone.
The record indicates that the primary outcome could not be represented as a comparison with at least two arms. It lists high-dose G-CSF, low-dose G-CSF, and placebo descriptions, but does not make clear which arm-level observations were available for the primary outcome or how they were analyzed. The arm descriptions should not be mistaken for reported outcome groups with analyzable results. No treatment comparison can be reconstructed from the information recorded.
Enrollment is recorded as 4. That figure is not enough to determine how many participants contributed to the primary endpoint, how many were assigned to each regimen, or whether any were missing endpoint data. Those details are not reported in the registry record. Even if outcome estimates were available, interpretation would depend on their precision as well as their point values. A confidence interval is a general statistical way to express uncertainty around an estimate; no such interval is reported for the primary endpoint.
The study status is TERMINATED. This status signals that the study did not proceed as planned to completion, but the record does not state why it was terminated or how termination affected enrollment, treatment, follow-up, or analysis. It would be speculation to attribute termination to a particular cause or to infer that it resulted from safety, efficacy, recruitment, or operational considerations.
The available safety record lists 0 serious adverse events affected in the recorded group and 3 other adverse events affected, with 4 at risk for each category. These counts are descriptive and should not be treated as evidence about the primary motor-function outcome. The record does not identify the kinds of other adverse events, provide participant-level descriptions, or report deaths as a numeric zero; deaths are recorded as null. Safety counts cannot fill the gap in primary-outcome reporting.
For these reasons, the posted information is best interpreted as a description of trial design and outcome definitions rather than a report that permits an effectiveness comparison. The purpose, interventions, outcome scale, enrollment, status, and limited safety counts are recorded. The primary endpoint findings and the analytical details needed to assess them are not reported in the registry record.
9. Statistical Methods Explained
Random allocation is intended to make treatment groups comparable on average at the start of a study. It does not guarantee that groups will be identical, particularly in a small study. The registry labels this study RANDOMIZED, but does not report the random-sequence method or allocation-concealment procedures. Those details would help readers assess how assignment was generated and whether it could have been anticipated.
What does masking mean?
Masking is intended to limit the influence of treatment knowledge on behavior, care, assessment, or interpretation. The registry labels the study TRIPLE masked but does not state which people were masked, how the treatments were made indistinguishable, or whether masking was assessed. The label is useful design information, but it does not document the success of masking in practice.
How should the endpoint be understood?
The primary endpoint is a mean score on UPDRS Part III, with the full range listed as its dispersion measure. The scale's reported limits are 0 to 108, and higher values indicate worse outcomes. A mean summarizes the group’s central score; a range conveys the spread from the lowest to the highest recorded score, but it can be sensitive to extreme observations. Neither the means nor ranges are reported by arm, so no numerical treatment contrast or descriptive distribution can be evaluated.
For a treatment comparison, an estimate of the difference between groups would describe the observed contrast. A confidence interval, in general, gives a range of values compatible with the data and analysis under its assumptions, and helps show precision. A p-value, in general, describes how unusual data at least as inconsistent with a specified null model would be if that model held. Neither a treatment contrast, confidence interval, nor p-value for the primary outcome is reported in the registry record. Their absence means the endpoint cannot be interpreted as evidence for or against a difference.
What does the planning illustration represent?
The stated sample-size assumptions describe a planning illustration based on the observed effect, with a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation. They also describe the effect to detect as a stated fraction of the observed effect. Such calculations are planning illustrations, not observed power and not evidence that the study had a particular probability of detecting an effect. The registry record does not report the trial's own sample-size justification or a protocol-based power calculation.
The assumptions refer to an observed effect, but the primary-outcome arm-level effect is not reported in the record. The record also does not offer a primary comparison with at least two arms for analysis. Consequently, the planning assumptions alone do not establish what effect was observed in this study or provide an interpretable estimate of the endpoint. No sample-size output should be read as an outcome result.
Why does over-dispersion matter in general?
Over-dispersion occurs when observed variability exceeds what a statistical model expects. In general, ignoring it can make uncertainty estimates too small and statistical tests too optimistic. The registered primary measure is a score mean with full-range dispersion, and the record does not report a fitted model, variance estimates, or an assessment of over-dispersion. It is therefore not possible to say whether over-dispersion was relevant to the analysis or how it was handled.
Different statistical methods may be appropriate depending on the endpoint, the distribution of scores, the comparison of interest, and the analysis population. The record does not report an analysis model, covariate adjustment, handling of baseline scores, or rules for excluding observations. It also does not report whether the primary endpoint was analyzed as a change from baseline or by comparing follow-up scores adjusted for baseline. The endpoint description names a baseline assessment and a later assessment, but does not specify the statistical contrast.
The record gives one outcome measure and one analysis, but those labels do not disclose the estimand, model, or analysis details. The statistical plan, including any pre-specified testing procedure, is not reported in the registry record. Without that information and without outcome estimates, it is not possible to assess model assumptions, precision, or whether the posted analysis followed a planned method.
These principles are general explanations of statistical methods. They do not establish which methods were used in this study. The registry identifies the design and the form of the primary endpoint, but the analysis procedures and numerical primary results are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry identifies one primary outcome measure and one analysis, but does not report a complete statistical analysis plan. It does not state whether the high-dose and low-dose regimens were each intended to be compared with placebo, whether comparisons between G-CSF regimens were planned, or how any multiple comparisons would be handled. A multiplicity procedure can help control the chance of false-positive findings when several hypotheses are tested; whether such a procedure was needed or used cannot be determined from the record.
The primary-outcome information does not provide arm-level results and indicates that the primary outcome could not be represented as a comparison with at least two arms. Thus, the record does not identify a testable primary comparison or report a result for one. The number of outcome measures and analyses alone does not clarify all comparisons, outcome time points, or analyses that may have been considered.
Missing-data methods are not reported in the registry record. The record does not state whether all enrolled participants contributed an endpoint score, how missing assessments were handled, or whether any sensitivity analyses were performed. It also does not state the analysis population, such as whether analysis followed randomized assignment or included only participants who completed treatment. Enrollment of 4 does not identify the endpoint denominator or the number analyzed in each arm.
These omissions limit assessment of selection bias, attrition, and the robustness of any result. No assumptions about missing outcomes, exclusions, interim analyses, or pre-specified testing should be inferred from the registry information.
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 |
|---|---|---|---|
| G-CSF Injection for Parkinson's Disease | 0 | 4 | 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 |
|---|---|
| G-CSF Injection for Parkinson's Disease | 3 of 4 |
Most frequent non-serious adverse event terms
| Event term | Organ system | G-CSF Injection for Parkinson's Disease |
|---|---|---|
| Musculo-skeletal soreness | Musculoskeletal and connective tissue disorders | 3 of 4 |
The registry lists a group titled “G-CSF Injection for Parkinson's Disease.” For this group, 4 are recorded as at risk for serious adverse events, and 0 as affected. For other adverse events, 4 are recorded as at risk and 3 as affected. The death entry is null, which is not the same as a reported count of zero; deaths are not reported in the registry record as a numeric result.
These are counts, not a complete account of event type, severity, timing, or attribution. The record does not list top serious adverse-event terms, and it does not identify the specific other adverse events. It also does not break the counts down by high-dose G-CSF, low-dose G-CSF, or placebo. The group label therefore cannot establish how the counts relate to each listed regimen.
Adverse-event counts are descriptive. They do not by themselves establish whether an event was caused by treatment or whether groups differed in safety. With no arm-specific breakdown or detailed event descriptions, the counts should be interpreted narrowly as the figures recorded for the named group, not as a comparative safety analysis.
12. What the Result Does, and Does Not, Mean
The registry record documents a randomized, triple-masked, parallel Phase 2 study of G-CSF and placebo for Parkinson disease, with motor performance on UPDRS Part III identified as the primary outcome. It provides regimen descriptions, an enrollment figure, a study status, and limited adverse-event counts. This information describes what the study was intended to examine and some features of its record.
It does not report primary-outcome scores by arm, a treatment-effect estimate, a confidence interval, or a p-value. Accordingly, it does not establish the direction, size, or precision of a difference in motor performance. The study purpose and endpoint description are not results, and the listed interventions do not demonstrate that either regimen changed the endpoint.
The record's status is TERMINATED, but no reason is given. That status does not reveal whether termination was related to treatment response, safety, recruitment, feasibility, or another cause. The recorded enrollment of 4 does not show how many participants were assigned to each regimen or assessed at follow-up. The gap between the endpoint's 2 years timeframe and its description of assessment after G-CSF injection one year is also unexplained.
The safety figures do not answer the primary efficacy question. They are not separated by the listed regimens, do not identify event types, and do not provide a numeric death count. The registry information therefore cannot support a treatment comparison on either motor function or safety.
Overall, the posted results are insufficient to determine what the study found about its primary question. This is not evidence that G-CSF did or did not affect motor performance; it is a limitation of the outcome information reported in the registry record. Any stronger conclusion would require results and analysis details that are not reported there.
13. Why This Trial Matters Statistically
This trial is statistically notable because the registry describes a randomized design but does not report the primary outcome results needed to evaluate the question it set out to address. A design label and a clearly named endpoint can explain the intended comparison, yet they do not substitute for arm-level observations, an effect estimate, and a measure of uncertainty.
The record also illustrates why outcome definitions and analysis populations must be distinguished. It names a motor score, describes a baseline and later assessment, and gives a timeframe, but the timeframe and assessment description do not align clearly. It does not identify which participants contributed endpoint data or how the listed regimens map to the primary analysis. Those gaps make it hard to judge whether an eventual estimate would represent the intended comparison.
Enrollment is recorded as 4, while the record gives no arm-specific endpoint results. In a small study, estimates can be imprecise and sensitive to individual observations; that is a general statistical concern, not a claim about the unreported results of this trial. Without reported estimates or uncertainty intervals, readers cannot assess that precision.
The record's termination status adds context but not an explanation. Statistical interpretation requires separating documented details from possible reasons for a study's course. The registry does not report the reason for termination, so no explanation should be inferred.
Finally, the safety record shows why event counts need context: group definitions, event descriptions, and arm-specific denominators are necessary to understand comparative patterns. The posted counts are limited and do not supply those details. Together, these features make transparent outcome reporting especially important for interpreting this study.
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 principal limitation is that primary-outcome results are not reported in the registry record. There are no arm-level UPDRS Part III means or full ranges, and no treatment contrast or uncertainty estimate. The recorded analysis could not be represented as a primary-outcome comparison with at least two arms. As a result, the central clinical question cannot be answered from the posted outcome information.
The registry lists high-dose G-CSF, low-dose G-CSF, and placebo descriptions but does not report participant allocation across them or explain which groups contributed to the primary outcome. It is not possible to determine the analysis denominator in each arm from the enrollment figure. Details of eligibility, participant characteristics, adherence, treatment discontinuation, and follow-up completion are not reported in the registry record.
There is an unresolved timing ambiguity: the endpoint timeframe is given as 2 years, while the endpoint description refers to assessment after G-CSF injection one year. The record does not explain how these statements relate. It also does not report the protocol, statistical analysis plan, missing-data procedures, analysis population, model, or adjustment strategy.
The study is marked TERMINATED, but the reason and consequences for data collection are not reported. Safety information is limited to counts for a named group, with no top serious-event terms and no numeric death count. The counts are not separated by the listed treatment regimens, so comparative safety cannot be assessed. These limitations concern what the registry record reports; they should not be used to infer unreported events, analyses, or reasons for the study's status.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study of the Neuro-protective Effect of Granulocyte-colony Stimulating Factor on Early Stage Parkinson's Disease — NCT01227681.
- Registry record last updated 2016-04-04; status last verified 2016-03.
- Results first posted 2016-04-04.
- 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
The registry describes a randomized, triple-masked, parallel Phase 2 study sponsored by Buddhist Tzu Chi General Hospital. The study concerns Parkinson Disease, is marked TERMINATED, and records enrollment of 4. Its start is listed as 2010-06 and primary completion as 2013-12.
The interventions are G-CSF and placebo, with high-dose and low-dose G-CSF regimens described alongside Sodium Chloride (NaCl) 0.9 % placebo. The primary outcome is mean UPDRS Part III motor-function scores, with higher scores indicating worse outcome. Its timeframe and assessment description are not fully aligned.
Arm-level primary-outcome results and the analysis details needed to interpret a treatment contrast are not reported in the registry record. Safety entries report 0 serious adverse events affected and 3 other adverse events affected in the named group; the death entry is null. The record does not explain termination or provide regimen-specific safety results.