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 Three Different Schedules of Low-Dose Decitabine in Myelodysplastic Syndrome (MDS) (NCT00067808), a randomized phase 2 study. The primary outcome is Participant Responses.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00067808 |
| Phase | Phase 2 |
| Condition | Myelodysplastic Syndrome, Chronic Myelomonocytic Leukemia |
| Allocation | Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 128 |
| Arms in the primary outcome | n/a |
| Lead sponsor | M.D. Anderson Cancer Center |
| Results posted | Yes |
2. Clinical Question
Population
The study concerned people with myelodysplastic syndrome (MDS) and chronic myelomonocytic leukemia. The primary outcome population is described as as-treated: 124 patients completed treatment. Eligibility criteria and further details about the enrolled population are not reported in the registry record.
Intervention
Decitabine was given using one of three schedules: 10 mg/m^2 intravenously over 1 hour daily for 10 days; 20 mg/m2 intravenously over 1 hour daily for 5 days; or 20 mg/m2 subcutaneously daily for 5 days. The study was intended to assess response and safety across these schedules.
Comparator
The three decitabine schedules served as the comparison groups in a randomized, parallel study. The registry does not report an allocation ratio or details of how the randomization sequence was generated. No masking was reported.
Primary question
The primary outcome was participant response to treatment after 8 weeks of therapy, classified using International Working Group criteria. The registry describes complete response, other response categories including partial remission, and no response. It does not report the number of participants in each response category or an analysis comparing the schedules.
3. Trial Design
This was a randomized phase II study with a parallel-group design. It compared three regimens of decitabine that differed in dose, route, or schedule. One group received 10 mg/m^2 intravenously over 1 hour daily for 10 days. Another received 20 mg/m2 intravenously over 1 hour daily for 5 days, and the third received 20 mg/m2 subcutaneously daily for 5 days. The registry reports no masking.
The study enrolled 128 participants and is recorded as completed. Its start is listed as 2003-10, with primary completion at 2009-05. M.D. Anderson Cancer Center is the sponsor. The conditions listed are myelodysplastic syndrome and chronic myelomonocytic leukemia.
The primary outcome is described as response after 8 weeks of therapy. The registry calls the outcome population as-treated and says that 124 patients completed treatment. That description does not establish how many participants were assigned to each group, how many were treated in each group, or how participants were handled if they did not complete treatment. Those details are not reported in the registry record.
Although randomization can support a comparison of assigned groups when its conduct and analysis are adequately described, the registry does not report the allocation ratio, sequence-generation method, or statistical plan. It also does not report whether the primary analysis followed assigned groups or used another approach. The posted results therefore do not permit reconstruction of the trial's main comparison from the design description alone.
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: Enrollment of 128 patients: 1 patient withdrew consent prior to treatment; 3 did not meet eligibility requirement for a total of 124 evaluable patients.
Overall Study
| Stage | Decitabine 10 mg/m2 IV | Decitabine 20 mg/m2 IV | Decitabine 20 mg/m2 SQ |
|---|---|---|---|
| STARTED | 17 | 93 | 14 |
| COMPLETED | 17 | 93 | 14 |
| NOT COMPLETED | 0 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: As treated: 124 patients completed treatment.
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 | Decitabine 10 mg/m2 IV | Decitabine 20 mg/m2 IV | Decitabine 20 mg/m2 SQ | Total |
|---|---|---|---|---|---|
| Participants analysed | 17 | 93 | 14 | 124 | |
| Age, Categorical: <=18 years | Participants | 0 | 0 | 0 | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 7 | 45 | 7 | 59 |
| Age, Categorical: >=65 years | Participants | 10 | 48 | 7 | 65 |
| Age Continuous | years | 67 (44 to 90) | 65 (37 to 83) | 64 (51 to 79) | 65 (37 to 90) |
| Sex: Female, Male: Female | Participants | 3 | 33 | 4 | 40 |
| Sex: Female, Male: Male | Participants | 14 | 60 | 10 | 84 |
| Region of Enrollment: United States | participants | 17 | 93 | 14 | 124 |
6. Primary Endpoint
The registry lists the primary outcome as Participant Responses, measured over Response to treatment after 8 weeks of therapy.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | Participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was participant response to treatment after 8 weeks of therapy. Responses were classified according to International Working Group criteria as complete response, other response—including partial remission—or no response. Complete response required normalization of peripheral blood and bone marrow with <5% bone marrow blasts and specified blood-count criteria. The registry's description of other response includes partial remission criteria and responses that fell short of complete response because of platelet recovery.
A response endpoint can describe whether participants reached defined disease-response categories within a stated assessment period. Its interpretation depends on clear definitions, consistent assessment, and reporting of the number of participants in each category. The categorical outcome also preserves distinctions between complete response, partial remission, and no response; combining categories would require a defined analysis decision.
The registry does not report the counts in these categories, the criteria used to handle unevaluable participants, or an inferential comparison between the treatment schedules. Thus, the endpoint definition is available, but the observed response distribution and the precision of any schedule-to-schedule difference are not reported in the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry describes a randomized comparison of three decitabine schedules, but it does not post the primary response counts. The outcome is defined as response after 8 weeks of therapy, classified into complete response, other response categories, and no response. Without the number of participants in each category for each schedule, the response findings cannot be characterized or compared from this record.
No effect estimate, confidence interval, or p-value for the primary outcome is reported. The record lists zero reported analyses. This means that the posted information does not establish whether the groups differed, nor how precisely any difference was estimated. It is not appropriate to infer response rates from the safety counts or from the number of participants who completed treatment.
The adverse-event information is separate from the primary efficacy endpoint. The registry reports serious and other adverse-event counts by group, along with a list of serious-event terms and percentages. These data describe events recorded in the registry, but they do not replace the missing response results. They also do not, on their own, establish that an event was caused by a treatment or support a statistical comparison between schedules.
The as-treated population is described as 124 patients who completed treatment, while the overall enrollment is 128. These figures refer to different descriptions of the study population; the registry does not provide a participant flow account explaining assignments, treatment receipt, completion, or inclusion in each analysis. The effect of any departures from assigned treatment or incomplete outcome assessment cannot be evaluated from the available record.
General statistical interpretation: an estimate describes the size and direction of a difference, while a confidence interval communicates the uncertainty around that estimate under the analysis assumptions. Neither is posted for the primary endpoint. A missing estimate is not evidence that the schedules were equivalent, and the record does not support a conclusion about the presence or absence of a response difference.
9. Statistical Methods Explained
The registry identifies this as a randomized phase II trial with parallel groups and no masking. These design labels describe the broad structure of the study; they do not specify the details needed to reproduce or fully assess its statistical analysis. The registry record does not report the randomization procedure, allocation ratio, planned sample-size justification, primary analysis method, or interim analyses.
What does randomization contribute?
General explanation: randomization assigns participants to groups by chance and is intended to reduce systematic differences between groups at the start of a trial. A credible analysis usually makes clear whether participants are analysed according to their assigned group or according to treatment received. The registry does not report the allocation ratio or the primary analysis population beyond describing the outcome population as as-treated. The record therefore does not show how the randomized assignment was carried through into the primary analysis.
How should the response endpoint be analysed?
The primary outcome has multiple categories: complete response, other response categories, and no response. A categorical outcome can be described with counts and proportions in each group. A comparative analysis could use a method suited to the category structure and the trial's estimand, but the particular method cannot be identified from this record. The registry says that the primary outcome has several categories or time points and was not reduced to one comparison. It does not provide outcome counts, an analysis specification, or a reported test. No single binary contrast should be assumed from the endpoint description.
General explanation: when outcome categories are combined, the choice of which categories to group affects the question being answered. For example, treating complete response as the sole event would ask a different question from combining complete response and partial remission. Any such grouping should be prespecified or clearly justified. The registry does not report a grouping rule or a primary contrast between the schedules.
What can be inferred from the adverse-event counts?
The registry lists the number at risk and the number affected by serious and other adverse events for each group. These are descriptive counts. A formal comparison would need a defined outcome, a clear analysis population, and a method that reflects whether the endpoint counts participants with events or recurrent events. The record does not report an inferential safety analysis. General explanation: if participants can experience more than one event, a count of events and a count of affected participants answer different questions. The registry does not clarify the event-counting details for the listed terms.
General explanation: over-dispersion matters when count data vary more than a chosen statistical model expects. In that situation, standard errors based on the simpler model can be too small, making uncertainty appear lower than it is. The posted safety information does not give the event-level data or model details needed to assess over-dispersion, and no such model is reported.
What do the planning assumptions mean?
The stated planning framework describes illustrations based on the observed effect, not the trial's own design justification. It specifies a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated share of the observed effect. For time-to-event outcomes, the framework describes total events using the Schoenfeld method; other outcomes use participants per arm. These are planning assumptions, not evidence that the trial had a particular sample-size target or achieved a particular level of power.
General explanation: a sample-size calculation is conditional on assumptions about the effect, variability, allocation, and analysis. It is a planning illustration rather than an observed trial result. The registry record does not report the trial's own sample-size justification, and no posted primary response comparison is available from which to interpret a planning illustration as a trial finding.
What uncertainty is reported?
No confidence intervals, p-values, or primary-outcome effect estimates are reported in the registry record. General explanation: a confidence interval describes a range of values compatible with the data under a specified method and assumptions. Its width conveys precision; it does not by itself determine whether a finding is clinically important. Without an estimate and interval, the precision of the response comparison cannot be assessed. The absence of reported inferential results also means that statistical significance cannot be evaluated from the registry entry.
10. Multiplicity, Missing Data and Analysis Populations
The primary endpoint is categorical, with complete response, other response categories, and no response. The registry does not report a single primary contrast across the three schedules, or whether any categories were combined for analysis. It also does not describe a multiplicity strategy for the possible group comparisons or outcome categories. The record therefore does not establish how the risk of false-positive findings across multiple tests was handled.
Missing-data methods are not reported in the registry record. The outcome population is described as as-treated, with 124 patients completing treatment, but there is no account of participants who lacked an assessment, withdrew, or were otherwise not included in the outcome population. The registry does not say how missing response classifications were handled or whether any sensitivity analyses were planned.
The record also does not report whether the primary analysis was based on randomized assignment, treatment received, or another defined population. The as-treated description identifies a population label but does not explain its operational definition. No interim analyses or statistical analysis plan are reported. The registry lists zero analyses, and no primary-outcome test or estimate is posted.
These omissions limit assessment of how the analysis addressed multiple comparisons, incomplete outcome information, and departures from assigned treatment. They do not show that a particular method was or was not used outside the registry record; those details are not reported in the registry record.
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 |
|---|---|---|---|
| Decitabine 10 mg/m2 IV | 5 | 17 | 29.4% |
| Decitabine 20 mg/m2 IV | 32 | 93 | 34.4% |
| Decitabine 20 mg/m2 SQ | 7 | 14 | 50.0% |
Other (non-serious) adverse events
Participants with at least one non-serious event at or above the registry's 0% reporting threshold.
| Arm | Participants affected of at risk |
|---|---|
| Decitabine 10 mg/m2 IV | 4 of 17 |
| Decitabine 20 mg/m2 IV | 32 of 93 |
| Decitabine 20 mg/m2 SQ | 8 of 14 |
Most frequent serious adverse event terms
| Event term | Organ system | Decitabine 10 mg/m2 IV | Decitabine 20 mg/m2 IV | Decitabine 20 mg/m2 SQ |
|---|---|---|---|---|
| Pain | General disorders | 4 of 17 | 13 of 93 | 3 of 14 |
| Death | General disorders | 0 of 17 | 6 of 93 | 1 of 14 |
| Infection | Infections and infestations | 2 of 17 | 3 of 93 | 0 of 14 |
| Pneumonia | Infections and infestations | 2 of 17 | 2 of 93 | 0 of 14 |
| Renal failure | Renal and urinary disorders | 2 of 17 | 1 of 93 | 0 of 14 |
| Cardiac Ischemia | Cardiac disorders | 1 of 17 | 2 of 93 | 0 of 14 |
| Dyspnea | Respiratory, thoracic and mediastinal disorders | 2 of 17 | 1 of 93 | 0 of 14 |
| Allergic Reaction | General disorders | 0 of 17 | 2 of 93 | 0 of 14 |
| Elevated cardiac triponin | Cardiac disorders | 0 of 17 | 1 of 93 | 1 of 14 |
| Febrile neutropenia | Infections and infestations | 0 of 17 | 1 of 93 | 1 of 14 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Decitabine 10 mg/m2 IV | Decitabine 20 mg/m2 IV | Decitabine 20 mg/m2 SQ |
|---|---|---|---|---|
| Nausea | Gastrointestinal disorders | 1 of 17 | 12 of 93 | 1 of 14 |
| Elevated alanine aminotransferase | Hepatobiliary disorders | 1 of 17 | 9 of 93 | 0 of 14 |
| Hyperbilirubinemia | Hepatobiliary disorders | 1 of 17 | 8 of 93 | 1 of 14 |
| Elevated aspartate aminotransferase | Hepatobiliary disorders | 1 of 17 | 7 of 93 | 0 of 14 |
| Fatigue | General disorders | 0 of 17 | 5 of 93 | 1 of 14 |
| Anorexia | Gastrointestinal disorders | 1 of 17 | 4 of 93 | 0 of 14 |
| Pain | General disorders | 0 of 17 | 3 of 93 | 1 of 14 |
| Vomiting | Gastrointestinal disorders | 0 of 17 | 3 of 93 | 0 of 14 |
| Alopecia | Skin and subcutaneous tissue disorders | 0 of 17 | 1 of 93 | 1 of 14 |
| Diarrhea | Gastrointestinal disorders | 0 of 17 | 1 of 93 | 1 of 14 |
Serious events with the highest arm-level rate: pain (23.5%), renal failure (11.8%), dyspnea (11.8%), infection (11.8%), pneumonia (11.8%).
For the 10 mg/m2 intravenous group, the registry lists 5 of 17 participants at risk as affected by serious adverse events and 4 of 17 as affected by other adverse events. For the 20 mg/m2 intravenous group, the corresponding counts are 32 of 93 and 32 of 93. For the 20 mg/m2 subcutaneous group, they are 7 of 14 and 8 of 14. These are descriptive registry counts, not adjusted comparisons between schedules.
The listed serious-event terms and percentages are pain, 23.5%; renal failure, 11.8%; dyspnea, 11.8%; infection, 11.8%; pneumonia, 11.8%; and adrenal insufficiency, 7.1%. The record does not explain the denominator or event-counting method for these percentages, or whether terms can refer to the same participant. Death counts are not reported in the registry record.
General explanation: a serious adverse event is a safety classification and does not, by itself, establish that the treatment caused the event. The registry does not report a causal assessment or an inferential comparison of these safety counts. Different group sizes and the absence of event-level detail limit what can be concluded from descriptive counts alone.
12. What the Result Does, and Does Not, Mean
The record establishes that a randomized phase II study compared three schedules of decitabine and identifies response after 8 weeks of therapy as the primary outcome. It also describes the response categories and posts adverse-event counts by group. These registry entries clarify what the study set out to assess and what safety information was recorded.
The record does not show how many participants achieved complete response, partial remission, another response, or no response. It provides no effect estimate, confidence interval, or p-value for the primary endpoint. As a result, it does not establish the direction, size, or precision of a response difference among the schedules. No conclusion about equivalence or lack of difference is supported by the absence of a reported comparison.
The adverse-event counts are descriptive and should be read separately from the response endpoint. They do not establish treatment causation or a statistically supported difference in safety. The serious-event terms are accompanied by percentages, but the denominator and counting details are not reported. The registry also does not report deaths.
General explanation: statistical evidence and clinical interpretation are related but distinct. A statistical estimate describes a comparison under a specified method; clinical importance depends on the meaning of the outcome and the context in which it is used. Neither can be fully assessed because the primary response results and analysis details are not reported in the registry record.
The appropriate interpretation is therefore limited to the study design, endpoint definition, and posted safety descriptions. The registry entry does not provide enough primary-outcome information to determine what response findings the trial observed.
13. Why This Trial Matters Statistically
This trial is statistically notable as a randomized comparison of three schedules of the same drug, rather than a comparison with an untreated or different-drug group. The regimens vary by dose, route, or treatment schedule, making the intended comparison one of alternative ways of administering decitabine. The parallel design and randomization are important features for understanding that question.
Its endpoint also illustrates why outcome definition matters. Response was classified into several categories using International Working Group criteria, rather than being described as a single undifferentiated event. The category definitions determine what a response means and what a statistical comparison would represent. Without category counts and a prespecified contrast, the endpoint cannot be translated into a quantitative comparison between schedules.
The entry also shows the distinction between a study's enrollment, its treatment-completion population, and the population used for an analysis. It reports enrollment of 128 and describes 124 patients as having completed treatment in the as-treated population, but does not provide a participant flow or primary analysis population details. These labels are not interchangeable when interpreting a trial.
Finally, the record demonstrates the importance of reporting estimates and uncertainty alongside design and endpoint descriptions. The primary response results and inferential analyses are not reported, so the main statistical question remains unresolved in the registry entry. The safety counts provide descriptive information but do not fill that gap or establish comparative effects.
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 the registry record does not report primary response counts by group. Although the response endpoint and assessment period are defined, the posted information contains no response estimate or inferential comparison. The direction and precision of any schedule-to-schedule difference therefore cannot be assessed.
Important design and analysis details are also absent. The record does not report an allocation ratio, randomization procedure, sample-size justification, primary analysis method, or interim analyses. It does not specify how missing response assessments were handled, how the as-treated population was defined beyond treatment completion, or whether analysis followed randomized assignment.
The response endpoint has several categories, but the registry does not identify a single primary contrast or explain how multiple comparisons were addressed. The record also does not report a statistical analysis plan. These gaps prevent a full assessment of the risk of selective analysis and the way uncertainty was quantified.
Safety information is limited to group-level counts and a list of serious-event terms with percentages. The record does not explain the denominator for the term percentages, provide event-level detail, or report death counts. It does not report a statistical safety comparison or causal assessment. These are limitations of the information in the registry record and do not establish what information may exist elsewhere.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Study of Three Different Schedules of Low-Dose Decitabine in Myelodysplastic Syndrome (MDS) — NCT00067808.
- Registry record last updated 2012-08-07; status last verified 2012-08.
- Results first posted 2011-05-26.
- 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 randomized phase II parallel-group study compared three decitabine schedules in a total enrollment of 128. The study began in 2003-10, and primary completion is listed as 2009-05. The sponsor was M.D. Anderson Cancer Center. No masking was reported.
The primary outcome was participant response after 8 weeks of therapy, classified as complete response, other response categories including partial remission, or no response. The registry describes an as-treated population of 124 patients who completed treatment, but does not report the response counts or a statistical comparison.
Adverse-event counts are posted by group. The registry does not report a primary-outcome estimate, confidence interval, p-value, sample-size justification, or statistical analysis plan. The main response findings and their precision are therefore not available in the registry record.