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 Consensus Method to Evaluate the Conformity of Prescription of a Chemotherapy (NCT02882178), a registered phase not stated study. The primary outcome is Items to Define Conformity to Cabazitaxel Conditions of Use.
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT02882178 |
| Phase | Phase not stated |
| Condition | Prostate Cancer |
| Allocation | Not Stated |
| Design model | Not Stated |
| Masking | Not Stated |
| Enrollment | 18 |
| Arms in the primary outcome | n/a |
| Lead sponsor | Institut Bergonié |
| Results posted | Yes |
2. Clinical Question
Population
The registry describes an observational cohort of people receiving cabazitaxel for metastatic castration-resistant prostate cancer in oncology centres in South-West France. It also describes two expert panels involved in selecting conformity criteria. The relationship between the registered enrollment of 18 and the cohort or panels is not reported in the registry record.
Intervention
The treatment of interest is cabazitaxel, described in the record as a second-line chemotherapy drug. The consensus process evaluates prescription conditions against items in its Summary of Product Characteristics, including indications, monitoring and conditions of use.
Comparator
There is no randomized treatment comparator described. The record concerns an observational cohort and a consensus process, not a comparison of cabazitaxel with another treatment. Allocation is not stated.
Primary question
Which items from the Summary of Product Characteristics should be selected by experts to assess whether cabazitaxel prescriptions conform to the stated conditions of use?
The clinical question is therefore about defining an assessment framework, rather than estimating a treatment effect. The record says that two independent expert panels were solicited: a French panel and a European panel from the Genito-Urinary group of the European Organization for Research and Treatment of Cancer. Their task was to judge the importance of each criterion in the product-characteristics document and support a qualitative assessment of prescription conformity.
The observational cohort is described as taking place in 32 oncology centres in South-West France. Its stated purpose is to examine routine prescribing and monitoring in relation to the selected criteria. The record does not report patient-level conformity results, nor does it report a comparison between prescribing strategies. The number of experts, the composition of the panels beyond the descriptions above, and the link between the registered enrollment and these groups are not reported in the registry record.
3. Trial Design
The registry identifies this as a completed study and describes an observational cohort, CABOBS, in 32 oncology centres in South-West France. Its focus is cabazitaxel prescription in routine practice for metastatic castration-resistant prostate cancer. The record also describes a formal consensus exercise intended to determine which product-characteristics criteria should define conformity of prescription. These are related but distinct activities: observation of prescribing practice and expert selection of criteria for assessing that practice.
The consensus process involved two independent panels: one French panel and one European panel from the EORTC-GU group. Experts were asked to assess the importance of criteria drawn from the Summary of Product Characteristics. The registry identifies the Delphi method, which uses iterative ratings and feedback to identify points of agreement or unresolved disagreement. It does not report the number of rating rounds, the process for combining panel judgments, the threshold for selecting an item, or whether the panels ultimately agreed.
The registered enrollment is 18. The record does not clarify whether this figure refers to cohort participants, experts, or another enrollment category, so it cannot be assigned to a particular study component. The study start is recorded as 2013-11 and primary completion as 2015-04; the status is COMPLETED. The sponsor is Institut Bergonié.
No randomized allocation or like-for-like control group is described. Allocation is not stated, and the registry indicates that this is not a randomized comparison. The primary outcome is a count of selected items, not a clinical outcome comparing treatments. The registry records one outcome measure and no analyses. Further design details, including recruitment procedures, eligibility criteria, and the timing and operational details of the cohort assessment, 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.
Overall Study
| Stage | Experts of the Consensus Process |
|---|---|
| STARTED | 18 |
| COMPLETED | 18 |
| NOT COMPLETED | 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 | Experts of the Consensus Process |
|---|---|---|
| Participants analysed | 18 | |
| Age, Customized: > 18 years | Participants | 18 |
| Sex: Female, Male: Female | Participants | 9 |
| Sex: Female, Male: Male | Participants | 9 |
| Race and Ethnicity Not Collected | Participants | — |
| Region of Enrollment: France | participants | 18 |
6. Primary Endpoint
The registry lists the primary outcome as Items to Define Conformity to Cabazitaxel Conditions of Use, measured over Baseline.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | items |
| Endpoint classification | not reduced to a single comparison |
The primary endpoint is the number of items selected from the 26 criteria in the cabazitaxel Summary of Product Characteristics. The selected items are intended to define a framework for judging whether prescriptions conform to the stated conditions of use. The registry describes criteria concerning such matters as indications, monitoring, contraindications, hepatic function, premedication for hypersensitivity, prophylactic treatments, dose and dose adjustment, and conditions of administration.
This endpoint is used because the study’s stated aim is to decide which product-characteristics criteria are important enough to contribute to a conformity assessment. The Delphi approach is presented as suitable when available evidence is limited and a recommendation or guideline cannot readily be derived from evidence alone. Expert judgment can help identify which criteria merit inclusion and provide a basis for a qualitative assessment.
The outcome is a count of selected criteria. It is not a measure of how many prescriptions were conforming, the proportion of patients meeting a clinical target, or a treatment effect. Although the outcome timeframe is recorded as Baseline, the registry does not report the observed number of selected items, item-level decisions, or the criteria ultimately retained. It also does not report a numerical agreement score or a rule for translating panel judgments into the final count.
7. Why No Re-analysis Is Shown
8. Statistical Interpretation
The registry record supports an interpretation of the study’s purpose and planned type of measurement, but not a conclusion about the final consensus result or routine prescribing conformity. It describes a Delphi process to select important criteria from the cabazitaxel Summary of Product Characteristics, and an observational cohort intended to assess practice against those criteria. The recorded primary endpoint is the number of criteria selected. The endpoint value is not reported in the registry record.
That absence matters for interpretation. Without the selected-item count or the final item list, a reader cannot determine which prescribing requirements were retained, how broad the resulting conformity framework was, or which aspects of the product-characteristics document were treated as most important. Without cohort results, a reader also cannot determine how often prescriptions met the selected criteria, which criteria were commonly unmet, or whether monitoring in routine practice matched the defined framework. No numerical estimate of conformity is reported.
The record does not report an estimated treatment effect or a randomized comparison. Cabazitaxel is the treatment context, but the main registered question concerns consensus-based measurement rather than whether cabazitaxel changes a clinical outcome. The result should therefore not be read as evidence for or against treatment efficacy, nor as a comparison of cabazitaxel with another therapy.
In general, a consensus process can make judgments more explicit by asking experts to assess criteria systematically and by using feedback to address disagreement. Agreement among selected experts is not, by itself, evidence that a criterion predicts patient outcomes or that following it improves outcomes. The registry does not report how agreement was quantified, the composition of the panels beyond their broad descriptions, or how the final selection was made.
The registered enrollment of 18 cannot be used to infer the number of cohort participants or experts because its meaning in relation to the study components is not specified. Likewise, the stated 32 centres describe the cohort setting but do not establish how many centres contributed data or how representative the observed prescribing was. No analyses are recorded. Consequently, the registry offers no reported estimate with which to judge precision, variability, or differences across settings.
Overall, the record describes a method and intended measurement target, not a report of the resulting consensus or cohort findings. Any account of the specific criteria selected, the degree of expert agreement, or the conformity observed in practice would go beyond what is reported in the registry record.
9. Statistical Methods Explained
What does a Delphi process do?
In general, the Delphi method is a structured approach for collecting and refining judgments from a group of experts. Participants rate or comment on candidate statements, receive feedback about the group’s responses, and may then reconsider their judgments. Iteration can help distinguish items with broad agreement from items where views remain divided. It does not guarantee agreement, remove all subjective judgment, or establish that a selected item is clinically valid.
In this study, the registry says that the candidate criteria came from the cabazitaxel Summary of Product Characteristics and that two independent panels were solicited. It describes iterative ratings with feedback as the basis for identifying disagreement or uncertainty. The actual rounds, feedback format, rating scale, decision thresholds, handling of missing expert ratings, and method for reconciling the French and European panels are not reported in the registry record. These details are important because different rules can yield different selected-item sets even when panels consider the same source criteria.
What does the primary count represent?
In general, a count outcome records how many qualifying items meet a defined rule. Here, the recorded endpoint is the number of product-characteristics items selected for assessing conformity. It is a count of criteria, not a count of patients, prescriptions, adverse events, or treatment responses. The registry states that the criteria are drawn from 26 items but does not report the final count or identify which criteria were retained.
Counts can be described using their distribution and can be analysed with methods suited to discrete outcomes if a suitable analysis is specified. General count models may require attention to whether variability is greater than expected under a simple model; over-dispersion can make standard errors too small if ignored. That is a general statistical consideration, not a claim about this study’s data or analysis. No model, distributional summary, uncertainty interval, or inferential test is reported in the registry record.
How should agreement be understood?
In general, agreement describes the extent to which assessors make similar judgments. It is distinct from the number of items selected: panels could select the same number of items but choose different criteria, or choose the same criteria with different levels of confidence. A count alone therefore does not fully describe the pattern of expert judgments. Item-level results and a stated agreement measure would help characterize the consensus process, but neither is reported in the registry record.
Expert agreement also has a different meaning from external validation. Agreement can indicate that a selected group reached a shared view through the specified procedure. It does not show that the criteria predict important outcomes, are interpreted consistently in clinical records, or capture every relevant aspect of prescribing. Those questions require evidence beyond a consensus exercise.
What can be inferred from the design?
The observational cohort is intended to describe routine practice rather than assign treatment. General observational studies can characterize how care is delivered, but their conclusions depend on how people and centres are selected, how information is collected, and how outcomes are defined. The record states that the cohort was planned across 32 oncology centres in South-West France, but does not report recruitment details, data completeness, or the number of centres contributing results. It therefore does not support an assessment of selection or measurement bias.
The record also identifies no randomized comparison and no analysis. In general, a randomized comparison is designed to support causal contrasts between assigned strategies, while an observational description does not have that same allocation basis. Here, the central registered outcome is a criteria count, so a treatment-effect interpretation would be misplaced in any case. The record does not state a statistical model, adjustment strategy, or analysis population.
What do planning assumptions mean?
In general, sample-size planning uses assumptions about a target effect, variability, significance level, allocation, and desired power to illustrate how much information a future comparison might require. Such calculations are planning illustrations, not observed evidence and not observed power. The registry’s planning description refers to a two-sided significance level of 0.05, equal allocation between two arms, a normal approximation, and an effect expressed as a fraction of the observed effect. It distinguishes event totals for time-to-event outcomes from participants per arm for other outcomes.
Those assumptions do not establish that this study had two treatment arms or that it performed a randomized comparison. The registry explicitly does not describe a randomized comparison, and no analyses are recorded. A comparison-based planning illustration cannot be interpreted as a design feature or result of the consensus study. The record does not report the effect estimate on which an illustration would depend or explain how those assumptions relate to the registered criteria-count endpoint.
In general, confidence intervals communicate the range of values compatible with a statistical estimate under a specified method and its assumptions. A narrow interval indicates greater precision than a wide one, but neither interval width nor statistical significance resolves problems of bias, measurement, or applicability. No confidence interval or inferential estimate is reported for the primary endpoint in the registry record.
10. Multiplicity, Missing Data and Analysis Populations
The registry records one primary outcome measure and no analyses. It does not report a statistical plan for handling multiple comparisons, multiple outcome tests, or repeated analyses. Because the endpoint is a consensus-based item count and no inferential results are recorded, there is no reported multiplicity adjustment to interpret. The record also does not state whether item-level judgments were treated as separate outcomes or how any such analyses would be controlled.
Missing-data procedures are not reported in the registry record. In general, missing ratings or incomplete cohort records can affect estimates if the missingness is related to the judgments or prescribing patterns under study. Methods such as complete-case analysis or imputation make different assumptions, and the appropriate approach depends on the data and analysis. No method, missingness summary, or sensitivity analysis is described.
Analysis populations are also not defined. The registered enrollment is 18, but the record does not explain which study component it refers to or how participants would be included in a particular analysis. The number of experts contributing ratings, the number completing each Delphi round, and the cohort analysis population are not reported in the registry record. It is therefore not possible to establish whether the endpoint would be calculated from all panelists, a subset, or a combined panel process.
The record does not report an intention-to-treat population, a per-protocol population, or another prespecified analysis set. These labels are typically relevant to studies with assigned treatment groups; the registry does not describe a randomized comparison. No adjustment for centre, panel membership, or other factors is reported. These omissions limit assessment of how consistently the planned question was translated into a reproducible analysis.
11. What the Result Does, and Does Not, Mean
The record describes an effort to establish which cabazitaxel product-characteristics criteria should be used to assess prescription conformity. This is a methodological and measurement question. It is not a report of the clinical effectiveness of cabazitaxel, a test of one treatment against another, or a demonstration that adherence to selected criteria improves outcomes.
The primary endpoint is the count of selected criteria, but the count and the selected criteria are not reported in the registry record. The record therefore does not show the final definition of conformity. It also does not give patient-level or prescription-level results that would reveal how often routine practice met that definition. The stated cohort setting and purpose do not substitute for those results.
In general, an agreed set of criteria can support consistent description by making the assessment rules more explicit. It may help researchers and clinicians examine whether relevant prescribing conditions are documented. But a consensus framework remains a measurement choice. Its usefulness depends on the rationale for item selection, the clarity of each criterion, and how reliably different assessors can apply it. Those properties are not established by the registry information alone.
Likewise, selecting criteria from an official product-characteristics document does not mean that every selected criterion has been tested as an independent predictor of outcomes. Expert agreement should not be mistaken for empirical validation or for proof of benefit from compliance. The registry does not report external validation, patient outcomes linked to conformity, or a comparison that could establish a causal effect.
The appropriate conclusion is limited: the study was designed to use expert consensus to define a conformity assessment and to examine cabazitaxel prescribing in an observational setting. The selected criteria, degree of agreement, observed conformity, and precision of any estimate are not reported in the registry record. No claim about treatment benefit or lack of benefit follows from the information recorded.
12. Why This Trial Matters Statistically
Statistically, this study illustrates that a clinical research question sometimes begins with defining what should be measured. Before estimating how often prescribing conforms to a standard, investigators need a rule for deciding which requirements count and how each requirement will be assessed. Here, that measurement framework was to be developed through expert review of items in the cabazitaxel Summary of Product Characteristics.
The Delphi method makes the judgment process more structured than an informal discussion by using iterative ratings and feedback. In principle, it can identify agreement and uncertainty when evidence is limited. Its statistical value depends on transparent reporting of how experts were selected, how ratings were collected, how disagreement was handled, and what rule determined item inclusion. Those operational details and the actual consensus results are not reported in the registry record.
The distinction between developing a measure and applying it is also important. A set of selected criteria defines what a conformity assessment will count, but it does not itself tell readers how often practice conforms. The cohort component would address that empirical question only if results were reported using a clear denominator, transparent criterion definitions, and an account of missing records. Such findings are not recorded.
This distinction helps prevent a common interpretive error: treating a carefully developed endpoint as if it were already a demonstrated clinical outcome. Consensus can improve consistency in measurement, while outcome data are needed to describe practice or examine consequences. The registry record offers the rationale and broad design, but no numerical endpoint result or analysis with which to evaluate either task.
13. 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 interpretation is that the registry describes the objective and endpoint but does not report the primary outcome value, the final selected criteria, or results from the observational cohort. Without these, the extent of consensus and the level of prescription conformity cannot be assessed.
The registered enrollment of 18 is not linked clearly to the cohort, expert panels, or another study component. The record names two panels and describes a cohort in 32 oncology centres, but does not report the number of experts, the number of participants assessed, or the number of centres contributing data. This prevents a clear account of the populations underlying the intended measurements.
Key consensus-process details are not reported: the number of Delphi rounds, rating scale, item-selection threshold, panel response rates, agreement measure, and procedure for resolving differences between panels. Without these details, reproducibility and the influence of panel composition cannot be evaluated.
The registry does not report recruitment and eligibility details, data-collection procedures, missing-data handling, analysis populations, statistical models, or uncertainty estimates. It also records no analyses. These limitations mean that the precision and potential sources of bias in any cohort or consensus result cannot be assessed from the registry record. Finally, the observational, non-randomized nature of the described cohort does not support a randomized treatment-effect comparison, and no such comparison is reported.
14. Related Tutorials
15. Related Statistical Calculators
16. Sources
- ClinicalTrials.gov: Consensus Method to Evaluate the Conformity of Prescription of a Chemotherapy — NCT02882178.
- Registry record last updated 2021-01-08; status last verified 2021-01.
- Results first posted 2021-01-08.
- 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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17. Record Summary
The completed study, sponsored by Institut Bergonié, concerns cabazitaxel prescription conformity in metastatic castration-resistant prostate cancer. The registry describes an observational cohort in 32 oncology centres in South-West France and a Delphi consensus process involving a French panel and a European EORTC-GU panel. The consensus objective was to select criteria from the cabazitaxel Summary of Product Characteristics.
The primary endpoint is the number of selected items from the 26 listed criteria, with the timeframe recorded as Baseline. Enrollment is recorded as 18, but its relationship to the cohort and expert panels is not specified. The study start is recorded as 2013-11 and primary completion as 2015-04; status is COMPLETED.
The registry records one outcome measure and no analyses. It does not report the selected-item count, final criteria, expert agreement, or cohort conformity results. No randomized comparison is described, and allocation is not stated.