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 Risk-Based Therapy in Treating Younger Patients With Newly Diagnosed Liver Cancer (NCT00980460), a non-randomized phase 3 study. The primary outcome is Event-free Survival.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00980460 |
| Phase | Phase 3 |
| Condition | PRETEXT I Hepatoblastoma, PRETEXT II Hepatoblastoma, PRETEXT III Hepatoblastoma |
| Allocation | Non-Randomized |
| Design model | Parallel |
| Masking | None (open label) |
| Enrollment | 236 |
| Arms in the primary outcome | n/a |
| Lead sponsor | National Cancer Institute (NCI) |
| Results posted | Yes |
2. Clinical Question
Population
Children with newly diagnosed hepatoblastoma across PRETEXT I, PRETEXT II, PRETEXT III, and PRETEXT IV disease were eligible for study treatment. The primary outcome calculation was limited to eligible patients.
Intervention
Treatment was assigned by risk group rather than randomized. The listed approaches included surgery, chemotherapy, liver transplantation when necessary, and risk-specific regimens. Temsirolimus was included in high-risk regimen H; the registry also lists regimen W, which was replaced by regimen H as of Amendment 3B.
Comparator
There was no like-for-like control group. The registry describes parallel risk groups receiving different treatment approaches, not randomized arms intended for direct comparison. Differences between groups therefore cannot be read as treatment effects without accounting for the reasons patients were placed in each group.
Primary question
The primary outcome was the estimated probability of remaining event-free through 5 years. An event was defined using progression, relapse or treatment failure, a second malignant neoplasm, or death, with follow-up ending at the last contact for patients without an event. The registry record does not report the estimated event-free survival result or its 95% confidence interval.
The study is titled “Risk-Based Therapy in Treating Younger Patients With Newly Diagnosed Liver Cancer.” Its official title specifies treatment of children with all stages of hepatoblastoma, with temsirolimus added to high-risk stratum treatment. The underlying clinical question is whether outcomes can be described for a treatment program organized around risk strata. Because treatment allocation was non-randomized and the groups received different regimens, the record does not support treating one group as a direct control for another.
3. Trial Design
This was a phase III, non-randomized, parallel study sponsored by the National Cancer Institute (NCI). Masking was recorded as none. The registry lists enrollment of 236 and status as completed. The recorded start date is 2009-09-15, and the primary completion date is 2020-06-30.
Risk categories corresponded to different treatment plans. The very low-risk group underwent surgery and received no further treatment. The low-risk group, regimen T, underwent surgery followed by adjuvant chemotherapy. The intermediate-risk group, regimen F, received C5VD chemotherapy. High-risk patients were listed under regimens W and H. Regimen W was replaced by regimen H as of Amendment 3B; the regimen H description includes vincristine, irinotecan, and temsirolimus. The registry also lists cisplatin, dexrazoxane, doxorubicin hydrochloride, fluorouracil, irinotecan hydrochloride, laboratory biomarker analysis, liver transplantation, and temsirolimus among interventions.
These are not exchangeable arms created by random assignment. The registry describes treatment based on risk group, so baseline prognosis and treatment intensity may differ between groups. Group-level outcomes can describe what was recorded for the study’s treatment strata, but they do not by themselves isolate the effect of a particular drug or regimen. The record does not report a randomized comparison or an analysis establishing a causal contrast among the treatment groups.
The study’s primary outcome was event-free survival (EFS), estimated with the Kaplan-Meier method. Its stated horizon was up to 5 years. Feasibility of referral for liver transplantation is listed as a secondary outcome. The registry record lists five outcome measures and zero analyses. It does not report a sample-size justification, interim analysis plan, or a detailed statistical analysis plan.
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.
Overall Study
| Stage | Very Low-risk Group | Low-risk Group (Regimen T) | Intermediate-risk Group (Regimen F) | High-risk Group (Regimen W) | High-risk Group (Regimen H) |
|---|---|---|---|---|---|
| STARTED | 8 | 51 | 105 | 32 | 40 |
| COMPLETED | 8 | 47 | 70 | 14 | 24 |
| NOT COMPLETED | 0 | 4 | 35 | 18 | 16 |
Reasons for not completing this period:
| Reason | Very Low-risk Group | Low-risk Group (Regimen T) | Intermediate-risk Group (Regimen F) | High-risk Group (Regimen W) | High-risk Group (Regimen H) |
|---|---|---|---|---|---|
| Death | 0 | 0 | 1 | 2 | 1 |
| Lack of Efficacy | 0 | 0 | 10 | 6 | 8 |
| Lost to Follow-up | 0 | 0 | 0 | 1 | 0 |
| Physician Decision | 0 | 0 | 11 | 5 | 3 |
| Withdrawal by Subject | 0 | 0 | 1 | 0 | 0 |
| Ineligible | 0 | 2 | 3 | 1 | 4 |
| Refusal of further therapy | 0 | 2 | 3 | 2 | 0 |
| No therapy within 42 days of resection | 0 | 0 | 3 | 1 | 0 |
| No transplant by protocol timepoints | 0 | 0 | 3 | 0 | 0 |
Analysis population for the primary outcome, as defined in the registry: Only eligible patients are considered in the calculation of this outcome measure.
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 | Very Low-risk Group | Low-risk Group (Regimen T) | Intermediate-risk Group (Regimen F) | High-risk Group (Regimen W) | High-risk Group (Regimen H) | Total |
|---|---|---|---|---|---|---|---|
| Participants analysed | 8 | 51 | 105 | 32 | 40 | 236 | |
| Age, Categorical: <=18 years | Participants | 8 | 51 | 105 | 32 | 40 | 236 |
| Age, Categorical: Between 18 and 65 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Categorical: >=65 years | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Age, Continuous | years | 2.5 (SD 2.56) | 1.59 (SD 1.71) | 1.42 (SD 2.61) | 2.31 (SD 2.4) | 2.75 (SD 2.9) | 1.84 (SD 2.5) |
| Sex: Female, Male: Female | Participants | 1 | 15 | 43 | 12 | 13 | 84 |
| Sex: Female, Male: Male | Participants | 7 | 36 | 62 | 20 | 27 | 152 |
| Ethnicity (NIH/OMB): Hispanic or Latino | Participants | 1 | 13 | 27 | 10 | 16 | 67 |
| Ethnicity (NIH/OMB): Not Hispanic or Latino | Participants | 7 | 35 | 73 | 22 | 23 | 160 |
| Ethnicity (NIH/OMB): Unknown or Not Reported | Participants | 0 | 3 | 5 | 0 | 1 | 9 |
| Race (NIH/OMB): American Indian or Alaska Native | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Asian | Participants | 1 | 5 | 8 | 2 | 6 | 22 |
| Race (NIH/OMB): Native Hawaiian or Other Pacific Islander | Participants | 1 | 0 | 0 | 0 | 0 | 1 |
| Race (NIH/OMB): Black or African American | Participants | 1 | 6 | 7 | 6 | 3 | 23 |
| Race (NIH/OMB): White | Participants | 5 | 29 | 75 | 20 | 25 | 154 |
| Race (NIH/OMB): More than one race | Participants | 0 | 0 | 0 | 0 | 0 | 0 |
| Race (NIH/OMB): Unknown or Not Reported | Participants | 0 | 11 | 15 | 4 | 6 | 36 |
| Region of Enrollment: United States | participants | 8 | 50 | 98 | 30 | 37 | 223 |
| Region of Enrollment: Canada | participants | 0 | 1 | 4 | 2 | 0 | 7 |
| Region of Enrollment: Australia | participants | 0 | 0 | 3 | 0 | 0 | 3 |
| Region of Enrollment: Japan | participants | 0 | 0 | 0 | 0 | 3 | 3 |
6. Primary Endpoint
The registry lists the primary outcome as Event-free Survival, measured over Time from patient enrollment to progression, treatment failure, death from any cause, diagnosis of a second malignant neoplasm, or last follow-up, assessed up to 5 years.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | 95% Confidence Interval |
| Unit | Percent Probability |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is event-free survival, expressed as a percent probability. It measures time from study enrollment until the first qualifying event or last follow-up. The registry’s timeframe description names progression, treatment failure, death from any cause, diagnosis of a second malignant neoplasm, or last follow-up. Its endpoint description names disease progression, disease relapse, a second malignant neoplasm, death from any cause, or last follow-up, whichever occurs first. Patients without an event are censored at last contact.
Time-to-event outcomes are useful when participants have different lengths of observation or when some have not experienced an event by the end of follow-up. Rather than treating every participant as if their outcome were fully observed for the same duration, the Kaplan-Meier method uses the timing of observed events and accounts for censoring. The resulting estimate describes the event-free probability over time under the study’s definition and follow-up process.
The registry record does not report the estimated 5-year EFS value or its 95% confidence interval. Thus, the endpoint definition and estimation method can be described, but the magnitude and precision of the study’s primary result cannot be evaluated from the registry record.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record establishes that EFS was the primary outcome and specifies how it was intended to be measured. It does not include an EFS estimate, a 95% confidence interval, or a reported comparison of treatment groups. Consequently, the primary outcome result itself is not reported in the registry record. The study’s completed status does not substitute for a numerical outcome estimate.
The design is important to interpretation. Patients were treated according to risk strata, and the study was non-randomized. Differences across the very low-risk, low-risk, intermediate-risk, and high-risk groups may reflect their different clinical risk and treatment plans as well as any other differences between the patients. They cannot be attributed to treatment alone on the basis of these group descriptions. The high-risk regimen W and regimen H records also represent treatment plans separated by an amendment, not two randomly assigned alternatives.
The registry’s adverse-event record presents group-level counts for serious adverse events, other adverse events, and deaths. These entries describe recorded events in the named groups; they are not a randomized safety comparison. The record lists serious adverse events affecting 0 in the very low-risk group, 0 in the low-risk group, 3 in the intermediate-risk group, 2 in high-risk regimen W, and 1 in high-risk regimen H. Those counts should be read alongside each group’s separately reported number at risk, not as proof that a regimen caused or prevented an event. The record does not establish causal attribution for the listed deaths.
For other adverse events, the registry records 0 affected in the very low-risk group, 24 in the low-risk group, 91 in the intermediate-risk group, 27 in high-risk regimen W, and 32 in high-risk regimen H. These are group-specific counts. The record does not give a formal comparison or adjustment for differences among strata, so comparing the counts as if they arose from equivalent groups would be misleading.
The listed serious-event terms include abdominal pain, cardiac arrest, cardiac disorders, disseminated intravascular coagulation, heart failure, and hypotension, each reported as 3.2%. These term-level figures do not provide enough information to determine comparative risk or causation. More broadly, interpretation is constrained by the absence of the primary EFS estimate and confidence interval, the non-randomized allocation, and the lack of a reported inferential analysis in the registry record.
9. Statistical Methods Explained
What does Kaplan-Meier estimation do?
Kaplan-Meier estimation is a general method for describing time until an event when follow-up duration varies and some participants have no recorded event before their last contact. It updates the estimated event-free probability at observed event times. Participants who have not had an event contribute information up to the time they are censored; censoring does not mean that an event occurred. In this study, the registry says patients without an event are censored at last contact.
The estimate is tied to the endpoint definition. Here, the registry describes progression or relapse, a second malignant neoplasm, and death as events, while its timeframe wording also refers to treatment failure. These events are combined into a time-to-first-event outcome: the first qualifying event ends event-free follow-up. The estimate therefore does not separately describe each event type.
What does a confidence interval communicate?
In general, a confidence interval conveys uncertainty around an estimated quantity. A narrower interval indicates greater statistical precision under the method’s assumptions, while a wider interval indicates less precision. The primary outcome lists a 95% confidence interval as its dispersion measure, but the registry record does not report the interval endpoints or the EFS estimate. The statistical precision of the primary result therefore cannot be assessed from this record.
Why does non-randomized allocation matter?
In general, random assignment helps balance measured and unmeasured prognostic factors across treatment groups, on average. In a risk-based, non-randomized design, treatment is linked to clinical risk strata instead. Prognosis and treatment intensity can therefore differ by design. Any contrast between strata may combine differences in patient risk, treatment, and other group characteristics. A direct causal treatment comparison would require an appropriate analysis and assumptions; the registry record does not report such a comparison.
The parallel model means that the registry describes groups followed within the same study rather than a crossover design. It does not make the groups comparable. Masking is recorded as none, and allocation is recorded as non-randomized. These design features should be kept in view when interpreting both outcomes and adverse-event counts.
How should the planning illustrations be understood?
The registry record describes sample-size illustrations as planning calculations based on the observed effect, not as the trial’s own design. Their stated assumptions are a two-sided significance level of 0.05, equal allocation between two arms, and a normal approximation; the effect to detect is a stated fraction of the observed effect. For time-to-event illustrations, the stated quantity is the total number of events using the Schoenfeld method; other illustrations use participants per arm.
These are planning illustrations, not observed power and not evidence that the study was originally designed around those assumptions. The record does not give a sample-size justification or a detailed account of the trial’s own design calculations. The registry’s description of a single comparison is also limited: the study’s risk strata are not a like-for-like control comparison, and the record states that the outcomes are not reduced to one comparison. No numerical planning values are reported in the registry record.
What can the recorded analyses establish?
The primary outcome description names Kaplan-Meier estimation, but the registry record lists zero analyses. It does not report a numerical EFS result, a group contrast, a test statistic, or a p-value. A method description identifies how an outcome is to be estimated; without the corresponding estimate and uncertainty, it does not show the size or precision of the result. No recalculated outcome result is available to interpret against a sponsor analysis.
More generally, event-time estimates depend on the completeness and timing of follow-up, the endpoint definitions, and the censoring process. The registry specifies censoring at last contact for patients without an event, but does not report additional diagnostics or sensitivity analyses. The record also does not describe how competing events, protocol changes, or deviations were handled in the primary analysis. Those details are not reported in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry record identifies EFS as the primary outcome and feasibility of referral for liver transplantation as a secondary outcome. It lists five outcome measures, but does not provide a multiplicity strategy for handling inference across outcomes, treatment strata, or other possible analyses. A prespecified testing hierarchy, adjustment method, or distinction between confirmatory and exploratory comparisons is not reported in the registry record. Because no analyses are listed, there are no reported inferential results from which to judge how multiple testing was addressed.
The primary outcome population is described as eligible patients only. The registry does not describe an intention-to-treat population, a per-protocol population, or how exclusions after enrollment were handled. Enrollment is listed as 236, but the eligible population size used for the primary endpoint is not stated in the outcome description.
For EFS, the registry says patients without an event are censored at last contact. That is the stated approach to incomplete event follow-up. It does not report other missing-data methods, follow-up completeness, reasons for loss to follow-up, or sensitivity analyses evaluating censoring assumptions. The record does not say how missing covariates or missing outcome information, if any, were handled.
These omissions limit the ability to assess whether the analysis population and follow-up process could affect the reported estimate. Since the primary estimate and its interval are also not reported, the degree of uncertainty due to missing follow-up cannot be evaluated from 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 |
|---|---|---|---|
| Very Low-risk Group | 0 | 8 | 0.0% |
| Low-risk Group (Regimen T) | 0 | 49 | 0.0% |
| Intermediate-risk Group (Regimen F) | 3 | 102 | 2.9% |
| High-risk Group (Regimen W) | 2 | 31 | 6.5% |
| High-risk Group (Regimen H) | 1 | 36 | 2.8% |
Deaths
| Arm | Deaths (participants affected of at risk) |
|---|---|
| Very Low-risk Group | 0 of 8 |
| Low-risk Group (Regimen T) | 3 of 49 |
| Intermediate-risk Group (Regimen F) | 7 of 102 |
| High-risk Group (Regimen W) | 11 of 31 |
| High-risk Group (Regimen H) | 13 of 36 |
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 |
|---|---|
| Very Low-risk Group | 0 of 8 |
| Low-risk Group (Regimen T) | 24 of 49 |
| Intermediate-risk Group (Regimen F) | 91 of 102 |
| High-risk Group (Regimen W) | 27 of 31 |
| High-risk Group (Regimen H) | 32 of 36 |
Most frequent serious adverse event terms
| Event term | Organ system | Very Low-risk Group | Low-risk Group (Regimen T) | Intermediate-risk Group (Regimen F) | High-risk Group (Regimen W) | High-risk Group (Regimen H) |
|---|---|---|---|---|---|---|
| Respiratory failure | Respiratory, thoracic and mediastinal disorders | 0 of 8 | 0 of 49 | 2 of 102 | 0 of 31 | 0 of 36 |
| Abdominal pain | Gastrointestinal disorders | 0 of 8 | 0 of 49 | 0 of 102 | 1 of 31 | 0 of 36 |
| Acute kidney injury | Renal and urinary disorders | 0 of 8 | 0 of 49 | 1 of 102 | 0 of 31 | 0 of 36 |
| Anemia | Blood and lymphatic system disorders | 0 of 8 | 0 of 49 | 1 of 102 | 0 of 31 | 0 of 36 |
| Ascites | Gastrointestinal disorders | 0 of 8 | 0 of 49 | 1 of 102 | 0 of 31 | 0 of 36 |
| Cardiac arrest | Cardiac disorders | 0 of 8 | 0 of 49 | 0 of 102 | 1 of 31 | 0 of 36 |
| Cardiac disorders - Other, specify | Cardiac disorders | 0 of 8 | 0 of 49 | 0 of 102 | 1 of 31 | 0 of 36 |
| Disseminated intravascular coagulation | Blood and lymphatic system disorders | 0 of 8 | 0 of 49 | 0 of 102 | 1 of 31 | 0 of 36 |
| Esophageal hemorrhage | Gastrointestinal disorders | 0 of 8 | 0 of 49 | 1 of 102 | 0 of 31 | 0 of 36 |
| Febrile neutropenia | Blood and lymphatic system disorders | 0 of 8 | 0 of 49 | 1 of 102 | 0 of 31 | 0 of 36 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Very Low-risk Group | Low-risk Group (Regimen T) | Intermediate-risk Group (Regimen F) | High-risk Group (Regimen W) | High-risk Group (Regimen H) |
|---|---|---|---|---|---|---|
| Febrile neutropenia | Blood and lymphatic system disorders | 0 of 8 | 7 of 49 | 50 of 102 | 19 of 31 | 14 of 36 |
| Hypokalemia | Metabolism and nutrition disorders | 0 of 8 | 4 of 49 | 37 of 102 | 7 of 31 | 16 of 36 |
| Infections and infestations - Other, specify | Infections and infestations | 0 of 8 | 4 of 49 | 26 of 102 | 16 of 31 | 7 of 36 |
| Aspartate aminotransferase increased | Investigations | 0 of 8 | 1 of 49 | 26 of 102 | 7 of 31 | 16 of 36 |
| Mucositis oral | Gastrointestinal disorders | 0 of 8 | 0 of 49 | 30 of 102 | 5 of 31 | 6 of 36 |
| Anorexia | Metabolism and nutrition disorders | 0 of 8 | 1 of 49 | 19 of 102 | 9 of 31 | 11 of 36 |
| Diarrhea | Gastrointestinal disorders | 0 of 8 | 4 of 49 | 12 of 102 | 8 of 31 | 13 of 36 |
| Hypophosphatemia | Metabolism and nutrition disorders | 0 of 8 | 0 of 49 | 18 of 102 | 6 of 31 | 13 of 36 |
| Alanine aminotransferase increased | Investigations | 0 of 8 | 1 of 49 | 21 of 102 | 7 of 31 | 6 of 36 |
| Vomiting | Gastrointestinal disorders | 0 of 8 | 2 of 49 | 19 of 102 | 9 of 31 | 4 of 36 |
Serious events with the highest arm-level rate: abdominal pain (3.2%), cardiac arrest (3.2%), cardiac disorders - other, specify (3.2%), disseminated intravascular coagulation (3.2%), heart failure (3.2%).
The safety record separates serious adverse events, other adverse events, and deaths by treatment group. For serious adverse events, the record lists 8 at risk and 0 affected in the very low-risk group; 49 at risk and 0 affected in the low-risk group; 102 at risk and 3 affected in the intermediate-risk group; 31 at risk and 2 affected in high-risk regimen W; and 36 at risk and 1 affected in high-risk regimen H. These are the registry’s group-specific counts, not a comparison adjusted for differences in risk or treatment.
For other adverse events, the respective counts affected are 0, 24, 91, 27, and 32, with group-specific at-risk counts of 8, 49, 102, 31, and 36. Deaths are separately listed as 0, 3, 7, 11, and 13 in those same groups. The record does not state that these deaths were caused by treatment, and they should not be interpreted as treatment-attributable deaths.
The most frequently listed serious-event terms are each reported as 3.2%: abdominal pain, cardiac arrest, cardiac disorders, disseminated intravascular coagulation, heart failure, and hypotension. These term-level entries do not identify a comparative risk or establish causality. Because the groups were non-randomized risk strata, differences in counts should be interpreted descriptively rather than as evidence that one regimen is safer than another.
12. What the Result Does, and Does Not, Mean
The study record describes a risk-based treatment program for children with newly diagnosed hepatoblastoma, with treatment plans varying by risk group. It documents a completed phase III study and defines EFS as the primary endpoint, estimated by Kaplan-Meier methods. The posted safety record also gives group-specific adverse-event counts. These details establish the design and the outcomes the registry intended to track.
However, the registry record does not report the estimated 5-year EFS probability or its 95% confidence interval. Without those values, the primary outcome’s magnitude and precision cannot be assessed. A completed study status does not answer whether the observed event-free survival was high or low, or how uncertain an estimate may be.
The study is not a randomized comparison. The risk groups were treated differently, and the group labels reflect different treatment plans and underlying risk categories. It would therefore be inappropriate to interpret differences in their adverse-event counts or any unadjusted outcome differences as the effect of a specific treatment. The registry record does not report a causal comparison among the regimens.
The adverse-event entries do show what the registry records in each group, including counts of affected participants and deaths. They do not establish that a listed event or death was caused by treatment. Nor do term-level percentages by themselves characterize the overall comparative safety of the regimens.
In short, the record can support a description of study design, endpoint definitions, treatment strata, and recorded safety counts. It cannot, as reported, support a numerical conclusion about the primary EFS outcome, a precise assessment of its uncertainty, or a like-for-like efficacy or safety ranking of the treatment groups.
13. Why This Trial Matters Statistically
This study is statistically notable because its treatment strategy is organized around risk rather than random assignment. That makes the distinction between describing outcomes and estimating treatment effects especially important. Group-specific event counts can be informative descriptions of the treatment experience, but they do not isolate the effect of treatment when groups differ by risk and regimen.
The primary endpoint also illustrates why an outcome definition and a numerical result are both needed. The registry specifies a time-to-event outcome, the event components, last-contact censoring, and Kaplan-Meier estimation. Those details clarify what the outcome is meant to represent. But without the estimated EFS probability and its confidence interval, readers cannot assess the result’s magnitude or precision.
Safety reporting likewise needs context. The registry presents serious and other adverse events by risk group, as well as death counts. These figures should be read as descriptive entries, not as comparative treatment effects. The group structure and non-randomized design make straightforward comparisons vulnerable to differences beyond treatment.
Finally, the record’s sample-size material is described as planning illustration rather than the study’s original design justification. Keeping planning calculations separate from observed outcomes helps prevent a common misreading: a planning scenario is not evidence of observed power or a substitute for the primary result. The record’s limited analysis reporting makes that distinction particularly important.
14. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
The main limitation for interpreting clinical outcomes is that the registry record does not report the primary EFS estimate or its 95% confidence interval. It also lists zero analyses, so no inferential comparison or numerical outcome analysis is available in the record. The completed status alone does not fill this reporting gap.
Allocation was non-randomized, and the arms are not a like-for-like control comparison. Patients were grouped by risk and received different treatment plans. Regimen W was replaced by regimen H as of Amendment 3B, so the two high-risk listings also reflect a treatment-plan change over the study. These features limit direct comparisons between groups.
The registry’s wording for the EFS timeframe and endpoint description is not identical: the timeframe refers to treatment failure, while the endpoint description refers to disease relapse. Both descriptions include progression, second malignant neoplasm, death, and follow-up to last contact. The record does not provide further detail about how these terms were operationalized or reconciled in analysis.
The primary population is described as eligible patients, but the record does not state the eligible analysis population size or explain exclusions. It does not report follow-up completeness, missing-data sensitivity analyses, multiplicity methods, interim analyses, or a detailed statistical analysis plan. The safety counts are not accompanied by a causal attribution or a randomized comparison. These limitations prevent stronger conclusions about treatment effects, precision, and comparative safety from the registry record alone.
15. Related Tutorials
16. Related Statistical Calculators
17. Sources
- ClinicalTrials.gov: Risk-Based Therapy in Treating Younger Patients With Newly Diagnosed Liver Cancer — NCT00980460.
- Registry record last updated 2026-06-30; status last verified 2026-05.
- Results first posted 2021-12-28.
- 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
NCT00980460 is a completed, phase III, non-randomized parallel study sponsored by the National Cancer Institute (NCI). It enrolled 236 and evaluated risk-based treatment for children with PRETEXT I through PRETEXT IV hepatoblastoma. Masking was recorded as none. The study start date was 2009-09-15, and the primary completion date was 2020-06-30.
The primary outcome was event-free survival, defined as time to a qualifying event or last follow-up and estimated by Kaplan-Meier methods. The registry record does not report the primary estimate or its 95% confidence interval. It lists feasibility of referral for liver transplantation as a secondary outcome, five outcome measures, and zero analyses. Treatment groups and adverse-event counts are recorded, but the non-randomized risk strata are not direct controls for one another.