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 Enalapril Maleate and Doxorubicin Hydrochloride in Treating Women With Breast Cancer (NCT00895414), a randomized na study. The primary outcome is Number of Patients With Doxorubicin Plasma Concentrations Demonstrating a Significant Increase or Decrease When Doxorubicin Was Given With Enalapril as Compared to When Doxorubicin Was Given Without Enalapril..
| Feature | Registry value |
|---|---|
| ClinicalTrials.gov identifier | NCT00895414 |
| Phase | NA |
| Condition | Breast Cancer |
| Allocation | Randomized |
| Design model | Crossover |
| Masking | None (open label) |
| Enrollment | 19 |
| Arms in the primary outcome | 2 |
| Lead sponsor | Masonic Cancer Center, University of Minnesota |
| Results posted | Yes |
2. Clinical Question
Population
Women with breast cancer receiving adjuvant doxorubicin treatment were the population of interest. The registry lists breast cancer as the condition and records enrollment of 19. It does not report further eligibility details or a fuller description of the analyzed population in the results record.
Intervention
The intervention was oral enalapril maleate given around a doxorubicin course. In one treatment sequence, enalapril began 1 week before course 1 and continued until day 8 of course 1. In the other sequence, it began 1 week before course 2 and continued until day 8 of course 2.
Comparator
The comparator was doxorubicin given without enalapril. Because the trial used a crossover model, participants were assigned to sequences that included both doxorubicin alone and doxorubicin with enalapril, in different orders. The registry does not report how sequence effects or period effects were handled in the analysis.
Primary question
The primary question was whether participants had a significant increase or decrease in doxorubicin plasma concentration when receiving doxorubicin with enalapril compared with receiving doxorubicin without it. The registry defined a mean increase or decrease of more than 115 ng/ml as significant. The posted outcome counts are zero for both conditions.
This is a pharmacokinetic question: it concerns drug exposure measured in plasma, rather than tumor response, survival, or a clinical measure of heart function. The registry describes serial plasma measurements at baseline and at 0.5, 1.0, 2.0, 4.0, 24.0 and 48.0 hours after doxorubicin infusion. Each participant was intended to have pharmacokinetic measurements with and without enalapril. The posted results identify participants with a significant change, rather than presenting the underlying concentration measurements or their average paired difference. Therefore, the result addresses the registry's threshold-based outcome, not the full pattern of plasma concentrations over time.
3. Trial Design
The registry describes a randomized, open-label crossover trial with enrollment of 19 and status recorded as completed. The phase is listed as NA. The sponsor was Masonic Cancer Center, University of Minnesota. The recorded start was 2009-04, and primary completion was 2014-04. These dates describe the record and do not establish when results were analyzed or posted.
Participants were assigned to one of two treatment sequences. In one sequence, participants received doxorubicin alone first, followed by doxorubicin with enalapril. In the other, they received doxorubicin with enalapril first, followed by doxorubicin alone. Both sequence descriptions specify doxorubicin on day 1, with treatment repeating every 14 days for 2 courses, subject to disease progression or unacceptable toxicity. The enalapril timing differed by sequence: it began 1 week before the course in which enalapril was given and continued until day 8 of that course.
A crossover design allows within-participant comparison across treatment conditions. In general, such a design can reduce the influence of stable differences between participants because each participant contributes measurements under both conditions. It also makes the order of treatment and the time period of measurement relevant. The registry does not report a washout period, how carryover was assessed, how period or sequence effects were modeled, or whether all participants completed both treatment periods.
The arm-level primary outcome results list 17 participants for doxorubicin alone and 17 for doxorubicin with enalapril. These are the recorded outcome denominators, not a report that every enrolled participant contributed complete paired measurements. The registry record does not explain the relation between the enrollment figure and these outcome denominators. It also does not report the allocation ratio, the randomization procedure, or details of masking beyond stating that masking was none.
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.
First Intervention (14 Days)
| Stage | Doxorubicin Alone First, Then Doxorubicin With Enalapril | Doxorubicin With Enalapril First, Then Doxorubicin Alone |
|---|---|---|
| STARTED | 9 | 10 |
| COMPLETED | 8 | 9 |
| NOT COMPLETED | 1 | 1 |
Reasons for not completing this period:
| Reason | Doxorubicin Alone First, Then Doxorubicin With Enalapril | Doxorubicin With Enalapril First, Then Doxorubicin Alone |
|---|---|---|
| Withdrawal by Subject | 1 | 0 |
| Physician Decision | 0 | 1 |
Second Intervention (14 Days)
| Stage | Doxorubicin Alone First, Then Doxorubicin With Enalapril | Doxorubicin With Enalapril First, Then Doxorubicin Alone |
|---|---|---|
| STARTED | 8 | 9 |
| COMPLETED | 8 | 9 |
| NOT COMPLETED | 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 | All Study Participants |
|---|---|---|
| Participants analysed | 19 | |
| Age, Categorical: <=18 years | Participants | 0 |
| Age, Categorical: Between 18 and 65 years | Participants | 18 |
| Age, Categorical: >=65 years | Participants | 1 |
| Sex: Female, Male: Female | Participants | 19 |
| Sex: Female, Male: Male | Participants | 0 |
| Region of Enrollment: United States | participants | 19 |
6. Primary Endpoint
The registry lists the primary outcome as Number of Patients With Doxorubicin Plasma Concentrations Demonstrating a Significant Increase or Decrease When Doxorubicin Was Given With Enalapril as Compared to When Doxorubicin Was Given Without Enalapril., measured over Baseline, 0.5, 1.0, 2.0, 4.0, 24.0 and 48.0 hours after infusion of doxorubicin.
| Element | Registry entry |
|---|---|
| Result type | Number |
| Measure of spread | not applicable |
| Unit | participants |
| Endpoint classification | Binary Endpoint |
The primary endpoint was the number of participants whose doxorubicin plasma concentration showed a significant increase or decrease when doxorubicin was given with enalapril, compared with doxorubicin without enalapril. Doxorubicin plasma concentration was identified as the primary pharmacokinetic measure of exposure. The registry describes repeated concentration measurements at baseline and at 0.5, 1.0, 2.0, 4.0, 24.0 and 48.0 hours after infusion.
The registry's threshold for a significant change was a mean increase or decrease of more than 115 ng/ml. This makes the reported endpoint a threshold-based count: it records whether a participant's change met the specified criterion, rather than reporting each concentration value or the magnitude and direction of every change. The posted count is 0 in the doxorubicin-alone condition and 0 in the doxorubicin-with-enalapril condition, with 17 recorded for each condition.
In general, a pharmacokinetic endpoint can help characterize how drug exposure differs under treatment conditions. A threshold can make a result easier to classify, but the count alone does not show how close measurements were to the threshold or how concentrations varied across the sampling times. The registry does not report the underlying concentration data, the participant-level paired changes, or the rationale for selecting the 115 ng/ml threshold. This endpoint does not directly measure tumor outcomes or cardiac clinical events.
7. Results Posted in the Registry
- Doxorubicin Hydrochloride With Enalapril: 0.0% (0/17) versus 0.0% (0/17) on control; risk difference 0.0 percentage points (95% CI 0.0 to 0.0); unadjusted two-proportion z-test p = n/a.
Risk difference: Doxorubicin Hydrochloride With Enalapril
95% CI: 0.0 to 0.0 percentage points
Recalculated from the posted summary statistics
8. Statistical Interpretation
The posted primary outcome records 0 participants with a significant increase or decrease in doxorubicin plasma concentration in the doxorubicin-alone condition and 0 in the doxorubicin-with-enalapril condition. Each condition has a recorded denominator of 17. The comparison is a risk difference of 0.0, with a confidence interval from 0.0 to 0.0 and a reported p-value of 0.0. These are the registry's posted values; they should be read alongside the limited outcome detail in the record.
The endpoint counts participants who crossed a defined threshold for a mean change, rather than measuring the size of a typical change. A zero count in both conditions means that no participant was recorded as meeting that threshold in either condition among the listed outcome participants. It does not establish that the concentration measurements were identical between conditions, that there were no smaller changes, or that every concentration at every sampling time was the same. The registry does not provide the continuous concentration data needed to examine those questions.
The crossover model is important to interpretation. In general, the most direct comparison in a crossover trial uses each participant's measurements under both conditions, while accounting for the treatment sequence and period. The registry says each participant was to have serial pharmacokinetic measurements twice, once with enalapril and once without it. However, the posted primary results are displayed as condition-specific counts, and the record does not describe the statistical analysis used to derive the comparison. It is therefore not possible to verify from the registry record whether the reported interval and p-value reflect a paired analysis, how incomplete paired observations were handled, or how sequence and period were considered.
The reported estimate is zero on the recorded risk-difference scale. The displayed confidence interval has identical lower and upper limits of 0.0, and the p-value is recorded as 0.0. The registry does not describe the method used to calculate these values or explain their apparent exactness. They should not be taken as proof of no underlying difference. The record also does not report a prespecified analysis plan, a sample-size justification, or a rationale for the inferential method.
These results address only the registry's primary threshold-based pharmacokinetic outcome. They do not establish whether enalapril affects other pharmacokinetic measures, cardiac biomarkers, clinical toxicity, cancer outcomes, or other outcomes. Two secondary outcome descriptions are listed, but results for them are not included in the posted outcome data summarized in the record. No conclusion about treatment benefit or harm can be drawn from the primary endpoint alone.
9. Statistical Methods Explained
The registry describes a randomized crossover design and a binary primary outcome expressed as a number of participants. The statistical interpretation of that outcome depends on how the participant-level measurements were classified and on how the within-participant comparison was analyzed. The record provides outcome counts and a risk-difference comparison, but it does not report a detailed statistical methods section or an analysis plan.
What does the binary outcome represent?
For this endpoint, each participant is classified according to whether the specified significant increase or decrease in doxorubicin plasma concentration occurred. The registry defines significance as a mean increase or decrease of more than 115 ng/ml. A binary outcome reduces a potentially detailed set of concentration measurements to a category: threshold met or not met. This can be straightforward to summarize, but it omits information about the size of changes that do not cross the threshold and about the pattern across individual sampling times.
The posted values are 0 participants in each condition, with 17 recorded for each. That is the full information available about the primary outcome counts in the registry results. The underlying plasma concentration measurements, the number of participants with complete pairs, and the detailed calculation of each participant's mean change are not reported in the registry record.
What is a risk difference?
In general, a risk difference compares the proportion of participants with an event in one condition with the proportion in another. It is expressed on the same scale as the event proportion. A value of 0.0 indicates no difference between the displayed event proportions. Here, the registry reports a risk difference of 0.0, with a confidence interval from 0.0 to 0.0. Because both posted event counts are zero and the listed denominators are the same, the displayed comparison has no observed difference in the binary outcome. No new estimate is needed to describe that posted result.
In a crossover study, however, treatment conditions are experienced by the same participant according to the assigned sequence. General methods for this design can use the paired structure, which captures whether an individual meets the endpoint under one condition but not the other. A comparison that treats the condition-specific counts as independent groups may not use that pairing. The registry record does not identify the method used, so the displayed risk difference should not be assumed to be a particular paired or unpaired estimator.
What does a p-value contribute?
In general, a p-value describes how compatible the observed data are with a specified statistical model under a null hypothesis. It does not measure the probability that a hypothesis is true, nor does it measure the size or importance of an effect. The posted p-value is 0.0. The registry does not report the test, its assumptions, or whether the value is rounded or generated by a method that can return zero. As a result, the p-value cannot be independently interpreted in detail from the record alone.
A zero event count in both conditions also limits what a significance test can say about differences in this binary endpoint. The absence of observed threshold events is not evidence that all underlying concentrations were equal, because the binary classification discards information below the threshold. Nor does a zero reported p-value resolve that limitation.
How should the crossover structure affect interpretation?
General crossover analysis must consider that observations from the same participant are related. It may also need to consider treatment order, period effects, and carryover from one condition into the next. The sequence descriptions show that participants received the conditions in opposite orders. The registry does not report whether there was a washout period, whether carryover was assessed, or which model accounted for repeated measurements. These omissions prevent a full appraisal of whether the analysis used the design as intended.
The record says each participant was to have serial pharmacokinetic measurements twice, once under each condition. Yet the outcome listing gives condition-specific denominators rather than a reported number of complete paired records. It does not state whether the denominator reflects all participants assigned, those measured, or those included in the final analysis. The analysis population and handling of missing measurements are not reported in the registry record.
What is not available about the statistical plan?
The registry does not report a sample-size justification, a planned statistical model, an interim analysis plan, or a prespecified method for the primary comparison. It also does not state whether analyses were adjusted for covariates, how multiple outcomes were handled, or how the 115 ng/ml threshold was selected. These details are important when judging whether a result was planned in advance and how much confidence to place in its inferential summaries.
General explanations of statistical methods do not fill in those missing trial-specific details. The posted figures should therefore be understood as the reported outcome summary, while the choices and assumptions behind the estimate remain unclear in the registry record.
10. Confidence Intervals and Precision
A confidence interval describes a range of values compatible with the data under a specified statistical method and its assumptions. In general, a narrower interval indicates greater precision for the parameter being estimated, while a wider interval indicates greater uncertainty. The interpretation also depends on the analysis model and the quality and completeness of the data.
The registry reports a risk difference of 0.0 and a confidence interval from 0.0 to 0.0 for the primary comparison. It does not explain the interval calculation, identify the confidence level, or describe the method used. The displayed limits are identical, but the record does not provide enough information to determine why the interval has that form or whether it reflects a boundary case, rounding, or another feature of the calculation. The interval should not be treated as proof that the true difference is known without uncertainty.
There are no threshold events reported in either condition, and the outcome denominators are 17 for each. This means the posted binary counts contain no observed contrast to estimate. It does not show that the underlying concentrations were identical: the endpoint does not report continuous values or changes that fall short of the specified threshold. The record also does not report the individual paired outcomes, which would be informative for assessing the crossover comparison.
Precision is distinct from the observed estimate. An estimate of 0.0 can coexist with substantial uncertainty, particularly when the endpoint is sparse or when the reported analysis is not fully described. The stated interval does not appear to convey that uncertainty in a way that can be assessed from the record. No independent precision calculation or alternative interval can be justified without additional data and methodological details.
The record does not report a sample-size justification or the number of complete paired observations used in the primary analysis. The enrollment figure and the condition-specific outcome denominators do not, on their own, establish how much information was available for the paired comparison. Thus, the registry's numerical interval is the only reported precision summary, but its construction and reliability cannot be evaluated from the available methods description.
11. Multiplicity, Missing Data and Analysis Populations
The registry lists a primary pharmacokinetic outcome and two secondary outcome descriptions. The secondary outcomes concern participants with significant increases or decreases in baseline levels of Btype Natriuretic Peptide, cardiac troponins, and urine microalbumin, and participants with significant increases or decreases in doxorubicin hydrochloride metabolite levels, with or without enalapril. The record does not include posted results for those outcomes in the results data; their results are not reported in the registry record.
When a trial evaluates multiple outcomes or multiple comparisons, the chance of at least one apparently unusual result can increase. General approaches to multiplicity include specifying a primary outcome in advance, controlling error across a family of tests, or interpreting secondary findings as exploratory. The registry identifies a primary endpoint, but does not report a multiplicity strategy, a hierarchy of testing, or whether the secondary outcomes were adjusted. The effect of multiplicity handling on interpretation is therefore unknown.
The record reports enrollment of 19 and primary outcome denominators of 17 in each condition. It does not explain the difference between enrollment and the outcome counts, identify reasons for missing data, or state whether the same participants contributed to both condition denominators. It does not report the number of complete participant pairs, a missing-data method, or sensitivity analyses. The analysis population is not reported in the registry record.
In general, missing measurements can affect a crossover analysis if the chance of missingness is related to treatment, sequence, participant characteristics, or the observed outcome. Whether any such issue occurred in this trial cannot be determined from the registry record. The record also does not state whether participants were analyzed according to assigned sequence or according to treatment received.
No interim analyses or stopping rules are reported in the registry record. The statistical plan, including any planned handling of missing outcomes and multiple comparisons, is not reported in the registry record. These omissions limit assessment of how the posted result relates to the intended analysis and how the secondary outcomes should be interpreted.
12. Safety Results
The registry reports serious adverse events as affected participants divided by participants at risk.
| Arm | Participants with serious adverse events | Participants at risk | Percentage |
|---|---|---|---|
| Doxorubicin Alone First, Then Doxorubicin With Enalapril | 0 | 8 | 0.0% |
| Doxorubicin With Enalapril First, Then Doxorubicin Alone | 0 | 9 | 0.0% |
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 |
|---|---|
| Doxorubicin Alone First, Then Doxorubicin With Enalapril | 3 of 8 |
| Doxorubicin With Enalapril First, Then Doxorubicin Alone | 2 of 9 |
Most frequent non-serious adverse event terms
| Event term | Organ system | Doxorubicin Alone First, Then Doxorubicin With Enalapril | Doxorubicin With Enalapril First, Then Doxorubicin Alone |
|---|---|---|---|
| dizziness | Nervous system disorders | 3 of 8 | 0 of 9 |
| tingling | Nervous system disorders | 0 of 8 | 1 of 9 |
| lightheaded | Nervous system disorders | 0 of 8 | 1 of 9 |
| cough | Respiratory, thoracic and mediastinal disorders | 1 of 8 | 0 of 9 |
| headache | Nervous system disorders | 0 of 8 | 1 of 9 |
| rash | Skin and subcutaneous tissue disorders | 0 of 8 | 1 of 9 |
| chest pain, NOS | Gastrointestinal disorders | 1 of 8 | 0 of 9 |
| fatigue | General disorders | 1 of 8 | 0 of 9 |
| palpitations | Cardiac disorders | 1 of 8 | 0 of 9 |
| food poisoning | Gastrointestinal disorders | 1 of 8 | 0 of 9 |
The safety results are listed by treatment sequence, not as a simple comparison of independent treatment groups. In the sequence receiving doxorubicin alone first and doxorubicin with enalapril later, 0 serious adverse events were recorded among 8 at risk, and 3 other adverse events were recorded among 8 at risk. In the sequence receiving doxorubicin with enalapril first and doxorubicin alone later, 0 serious adverse events were recorded among 9 at risk, and 2 other adverse events were recorded among 9 at risk. The registry does not list deaths for either sequence.
These counts are sequence-level safety summaries. Because participants received both treatment conditions in different orders, the groups do not represent separate populations exposed exclusively to one condition. The registry does not attribute each other adverse event to a treatment period or identify event types in the posted safety summary. It also does not report exposure time or the statistical method for comparing adverse events.
In general, counts of adverse events are not by themselves evidence that a treatment caused an event or prevented one. Zero serious events in the posted sequence summaries does not establish that serious harms could not occur, particularly when the record provides limited detail about event ascertainment and exposure. The other-event counts should likewise be read as reported counts, not as estimates of comparative risk. The registry does not provide enough information for a treatment-specific safety comparison.
13. What the Result Does, and Does Not, Mean
The primary posted result is that 0 participants met the registry's threshold for a significant increase or decrease in doxorubicin plasma concentration in either treatment condition. The listed denominator is 17 for doxorubicin alone and 17 for doxorubicin with enalapril. The reported risk difference is 0.0, with a confidence interval from 0.0 to 0.0 and a p-value of 0.0. These are the recorded values for the threshold-based outcome.
That result does not mean that doxorubicin concentrations were exactly the same with and without enalapril. The endpoint classifies changes using a threshold of more than 115 ng/ml; changes that do not meet that criterion are not counted as significant events. The registry does not provide the concentration measurements, individual changes, or their distribution. It is therefore not possible to determine how large smaller changes were or whether the concentration-time profiles differed in other ways.
The result also does not establish equivalence between conditions. Demonstrating equivalence generally requires a prespecified margin and an analysis designed to assess whether uncertainty falls within that margin. The registry does not report such a margin or an equivalence analysis. The displayed confidence interval is reported as 0.0 to 0.0, but the calculation method is not described, so it cannot be used to verify an equivalence claim.
The endpoint is pharmacokinetic, not a direct assessment of cancer control, heart protection, cardiac injury, or overall safety. The registry's description of the trial's rationale mentions possible heart-cell protection, but the primary posted result concerns plasma concentration. The listed secondary outcomes concern biomarkers and doxorubicin metabolites, but results for them are not reported in the registry record.
Finally, the crossover design makes the within-participant comparison and treatment sequence relevant. Although the record describes measurements under both conditions, it does not report the paired analysis details, handling of missing data, or assessment of period and carryover effects. The result should therefore be read as a limited report of the recorded binary outcome, rather than a complete account of drug exposure or clinical effects.
14. Why This Trial Matters Statistically
This trial raises a useful statistical issue: a clinically interesting pharmacokinetic question can be reduced to a binary threshold outcome, and that choice determines what the reported counts can tell readers. The registry defines a significant mean increase or decrease as more than 115 ng/ml, then reports the number meeting that criterion. The posted counts are zero for both conditions. Those counts answer whether participants crossed the chosen threshold, but they do not show the size or direction of changes below it.
The crossover design also highlights the importance of matching analysis to design. In general, within-participant comparisons can account for stable differences between people, but they require analysis that respects paired observations and may need to consider sequence and period effects. The record describes opposite treatment orders and repeated measurements, yet does not identify the statistical model or report complete-pair counts. This makes the methodological details central to interpreting the estimate.
The confidence interval is another reason to look beyond a point estimate. A zero risk difference is the posted estimate, and the reported interval has the same lower and upper values. Without the calculation method and the underlying paired data, that display does not allow readers to assess precision independently. A numerical result can look exact while important uncertainty and assumptions remain undocumented.
The record also illustrates the distinction between a registry outcome listing and a full statistical account. It identifies secondary outcome topics and safety counts, but does not report a multiplicity strategy, missing-data approach, or detailed analysis population. These are not peripheral details: they affect how well the results can be appraised and reproduced. The trial is statistically informative as an example of why outcome definitions, design structure, and analysis reporting need to be considered together.
15. Limitations
- The posted summary statistics are the only data these results rest on; patient-level data, full protocols and statistical analysis plans are not available.
- Recalculated results are simple, unadjusted calculations from posted summaries. They do not replace the sponsor's prespecified analysis.
Several trial-specific details needed to interpret the primary result are not reported in the registry record. The primary endpoint uses a threshold of more than 115 ng/ml, but the rationale for that threshold and the calculation of each participant's mean change are not described. The continuous concentration data and participant-level paired outcomes are also absent, preventing evaluation of changes that did not cross the threshold.
The record describes a crossover design but does not report the planned statistical model, how paired observations were used, or whether treatment sequence, period effects, and carryover were considered. It does not specify whether a washout period was used. These omissions matter because the treatment conditions were administered in different orders, and outcomes measured within one participant are related.
The relationship between enrollment of 19 and the outcome denominators of 17 in each condition is not explained. The number of complete pairs, reasons for missing measurements, analysis population, and method for handling missing data are not reported. The registry also does not report a sample-size justification, interim analysis plan, or a detailed prespecified statistical plan.
The posted confidence interval is 0.0 to 0.0, but the method used to calculate it is not described. The record does not identify the test underlying the reported p-value of 0.0 or explain its precision. Two secondary outcomes are listed, but their results are not reported in the registry record, and no multiplicity strategy is described. The safety summaries are reported by sequence and do not provide treatment-period attribution for other adverse events. Together, these limitations mean the posted results offer only a partial account of the planned pharmacokinetic and safety questions.
16. Related Tutorials
17. Related Statistical Calculators
18. Sources
- ClinicalTrials.gov: Enalapril Maleate and Doxorubicin Hydrochloride in Treating Women With Breast Cancer — NCT00895414.
- Registry record last updated 2019-05-08; status last verified 2019-05.
- Results first posted 2019-05-08.
- 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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19. Record Summary
The registry record describes a completed randomized, open-label crossover trial of doxorubicin with and without enalapril in women with breast cancer. Enrollment was 19. Participants were assigned to treatment sequences that gave the two conditions in opposite orders. The primary endpoint counted participants with a significant increase or decrease in doxorubicin plasma concentration, defined as a mean change of more than 115 ng/ml.
The posted primary outcome lists 0 participants with a significant change in each condition, with 17 recorded for each. The reported risk difference is 0.0, the confidence interval is 0.0 to 0.0, and the p-value is 0.0. Details of the statistical method, paired analysis, missing data, and precision calculation are not reported in the registry record. Two secondary outcome descriptions are listed, but their results are not reported in the registry record.