Statin Therapy for Ischemic and Nonischemic Cardiomyopathy: Complete Statistical Analysis

1. Trial at a Glance

This page covers the registry results for Statin Therapy for Ischemic and Nonischemic Cardiomyopathy (NCT00701220), a non-randomized phase 4 study. The primary outcome is Change in Endothelial Progenitor Cells.

2. Clinical Question

The study description also asks whether treatment is accompanied by improvement in damaged heart areas documented by MRI scans. That aim is part of the brief summary, while the registered primary outcome is change in endothelial progenitor cells. The MRI outcome’s specific definition and numerical findings are not reported in the registry record.

The registered endpoint is a continuous measure expressed as a percentage of EPCs. The registry describes collecting blood, processing white blood cells, identifying cell populations that contain EPCs, and comparing fluorescent cell counts with unstained cells to address background fluorescence. This provides the measurement context, but not the outcome values or a treatment-effect estimate.

Accordingly, the clinical question can be described from the stated aims and endpoint, but it cannot be answered from the numerical results in the registry record. It is not possible to determine the direction or size of the EPC change, its uncertainty, or whether the groups differed. Nor can the MRI aim be evaluated using the posted information.

3. Trial Design

The registry identifies this as a phase 4, non-randomized, open-label, parallel study. Its listed enrollment is 9, and its status is completed. The record gives a start date of 2007-04 and a primary completion date of 2010-12. Philip Binkley is listed as sponsor.

The group descriptions name people with ischemic cardiomyopathy receiving Lipitor (atorvastatin calcium), people with nonischemic cardiomyopathy receiving Lipitor treatment, and healthy subjects with no history of high cholesterol, heart disease, or heart attacks. The registry lists Atorvastatin Calcium as a drug intervention. It does not explain how participants entered each group, whether the healthy subjects received any intervention, or how the groups were intended to be compared; these details are not reported in the registry record.

Non-randomized allocation means that the record does not describe random assignment. The groups therefore should not be read as if randomization had made them comparable at baseline. Differences between groups could reflect differences in participant characteristics, clinical status, treatment, or other factors; which factors were present is not reported in the registry record. Open-label status means the study is listed as having no masking. Who knew the treatment or group assignments is not further specified.

The parallel model indicates that the listed groups are separate groups rather than a stated within-person crossover design. The record does not describe the allocation process, eligibility criteria, planned follow-up schedule beyond the primary endpoint timeframe, or treatment duration in sufficient detail. It also does not report a protocol-level rationale for the group structure or enrollment target.

The primary outcome is change in endothelial progenitor cells from baseline to 6 months. Two outcome measures and one analysis are recorded, but the numerical primary outcome results and details of the analysis are not reported in the registry record. The study design and stated aim can therefore be described, while comparative effectiveness and the precise conduct of the analysis remain unclear.

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: Patients with cardiomyopathy on the basis of valvular heart disease or who had a myocardial infarction within six months prior to study enrollment were excluded from the study.

Overall Study

Reasons for not completing this period:

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.

6. Primary Endpoint

The registry lists the primary outcome as Change in Endothelial Progenitor Cells, measured over Baseline - 6 months.

The primary endpoint is titled “Change in Endothelial Progenitor Cells” and is measured as a percentage of EPCs. It is classified as a continuous outcome summarized by a mean and standard deviation. The stated timeframe is Baseline - 6 months. These details identify the type of measurement and the period over which change was intended to be assessed, but the actual baseline and follow-up values are not reported in the registry record.

The measurement description says that white blood cells were extracted from blood samples and labeled using the ALDEFLOUR system. Facscan analysis was used to isolate lymphocytic and monocytic cell lines, which contain the EPC populations, using forward versus side scatter plots. Fluorescent cells in the ALDEFLUOR frequency range were then enumerated. Unstained cells with the same back scatter range were used for comparison to correct for background fluorescence.

As a general measurement principle, a biomarker endpoint can provide a quantifiable biological measure that relates to a study’s stated scientific question. In this study, the endpoint aligns with the stated aim of assessing whether atorvastatin is associated with a change in circulating EPCs. The brief summary separately mentions MRI assessment of damaged heart areas, but that measure is not the registered primary endpoint.

The record does not report the observed mean change, its standard deviation, a between-group contrast, or an uncertainty interval. Thus, the measurement method and intended timeframe are available, but the size and precision of the endpoint result cannot be assessed from the registry record.

7. Why No Re-analysis Is Shown

8. Statistical Interpretation

9. Statistical Methods Explained

The registered primary endpoint is a continuous outcome: change in endothelial progenitor cells, measured as percentage of EPCs over Baseline - 6 months. The registry identifies the summary parameter as a mean and the dispersion measure as a standard deviation. These labels describe how the outcome was intended to be summarized. They do not reveal the observed mean or variability, which are not reported in the registry record.

What does a mean change represent?

As a general statistical concept, a mean summarizes the average value of a measurement across the participants included in an analysis. For a change endpoint, the analysis ordinarily compares a measurement at follow-up with a measurement at baseline for each participant, then summarizes those changes. The registry’s title and timeframe identify a change endpoint, but the exact calculation used to derive each participant’s change and the analysis population are not reported in the registry record. No numerical change can be reconstructed from the endpoint description alone.

A standard deviation describes how spread out individual measurements or changes are around their mean. It is not the same as the uncertainty in the estimated mean: uncertainty also depends on the amount of information in the analysis. The registry identifies standard deviation as the dispersion measure but does not report its value. This means neither the observed variability nor the precision of the average can be evaluated.

How does the cell measurement work?

The endpoint description lays out a laboratory procedure. White blood cells were extracted from blood samples and labeled with the ALDEFLOUR system. Facscan analysis separated lymphocytic and monocytic cell lines using forward versus side scatter plots. The record notes that these cell lines contain the EPC populations. Fluorescence in the ALDEFLUOR frequency range was used to enumerate progenitor cell lines, and fluorescent-cell measures were compared with unstained cells in the same back scatter range to correct for background fluorescence.

As a general measurement principle, a comparison with a background signal can help distinguish the signal of interest from fluorescence not attributable to the labeled cells. The description explains that purpose, but it does not report laboratory quality-control results, repeatability, assay performance, or whether all samples were processed under identical conditions. Those details are not reported in the registry record.

What can an unmasked, non-randomized design tell us?

The study is listed as non-randomized, with no masking, and a parallel model. In general, randomization is used to reduce systematic differences between groups at the point of assignment. Without random assignment, pre-existing group differences can complicate attribution of an observed change to treatment. Masking can reduce some influences of knowledge of group assignment on care, measurement, or reporting; no masking is listed for this study. Which specific protections or adjustment methods were used is not reported in the registry record.

A parallel design follows separate groups rather than describing a crossover in which each participant receives multiple treatments in sequence. The registry does not specify how group membership was determined, whether baseline characteristics were balanced, or which covariates were considered in the analysis. The healthy-subject group is listed, but its role in the EPC analysis is not described. Because group assignment and the analysis model are not reported, the intended comparison cannot be fully reconstructed.

How should the planning illustration be understood?

The record describes a planning illustration computed from the observed effect, not from the trial’s own design. It states that the illustration uses a two-sided significance level of 0.05, equal allocation, and a normal approximation. These are assumptions for a planning calculation, not reported features of the actual allocation process. The record says that the illustration’s effect to detect is a stated fraction of the observed effect, but the fractions and resulting sample-size figures are not reported in the registry record.

As a general concept, a sample-size calculation estimates how much information may be needed to detect a specified effect under stated statistical assumptions. Such an illustration is not a measure of what the study achieved, nor does it show that the study had a particular probability of detecting an effect after the data were collected. It is not observed power. The registry explicitly distinguishes its planning illustration from the trial’s own design, and it does not report the planning results in the available record.

Why are effect estimates and uncertainty both needed?

A numerical estimate describes the size and direction of an observed contrast or change. An interval estimate, such as a confidence interval, expresses uncertainty around that estimate under the model and assumptions used. In general, a narrow interval indicates greater precision than a wide one, while the interval’s position relative to a null value can help describe compatibility with no difference. These concepts cannot be applied to the primary endpoint because the estimate and interval are not reported in the registry record.

A p-value is another inferential summary, interpreted in relation to a specified null hypothesis and model. It does not measure the probability that a treatment is effective, and it does not replace an effect estimate or its interval. No p-value, statistical test, model specification, or adjustment strategy for the primary outcome is reported in the registry record. The record lists one analysis but does not provide enough detail to identify what that analysis tested.

For a continuous outcome, distributional assumptions may matter to the validity of model-based inference. The planning illustration mentions a normal approximation, but that does not establish which model was used for the trial’s primary analysis or whether assumptions were checked. Those details are not reported in the registry record. Since the endpoint values and analysis details are absent, statistical significance, precision, and robustness cannot be assessed.

10. Multiplicity, Missing Data and Analysis Populations

The registry lists two outcome measures and one analysis. The primary outcome is identified as change in endothelial progenitor cells. The other outcome measure’s definition and results are not reported in the registry record. The record does not describe a multiplicity strategy, such as how inference was prioritized across outcomes or how any adjustment for multiple comparisons was handled.

As a general statistical issue, testing several outcomes or comparisons can increase the chance of obtaining at least one apparently unusual result under a set of null hypotheses. A prespecified hierarchy or an adjustment approach can address that concern, but the registry record does not report whether either was used. The number of listed outcomes alone does not establish how many statistical tests were performed.

The record does not report missing-data counts, reasons for missingness, the number with endpoint measurements at baseline or follow-up, or the method used to handle missing observations. It also does not identify an intention-to-treat, per-protocol, or other analysis population. Enrollment of 9 does not tell readers how many participants contributed to the primary endpoint analysis.

As a general principle, missing data can affect both the amount of information and the validity of an estimate, particularly when the chance of missingness is related to participant characteristics or outcomes. Without details of completeness and handling, the impact of missing observations cannot be assessed. The analysis population and missing-data approach are not reported in the registry record.

11. Safety Results

The registry reports serious adverse events as affected participants divided by participants at risk.

Other (non-serious) adverse events

Participants with at least one non-serious event at or above the registry's 5% reporting threshold.

The registry reports serious and other adverse-event counts for the ischemic cardiomyopathy and nonischemic cardiomyopathy groups. For the ischemic cardiomyopathy group, the number listed at risk is 1, with 0 serious adverse events and 0 other adverse events. For the nonischemic cardiomyopathy group, the number listed at risk is 4, with 0 serious adverse events and 0 other adverse events. The registry does not list serious adverse-event terms.

These figures are counts within the reported groups. They should not be interpreted as precise estimates of safety risk: the listed groups are small, and the registry record does not report the safety observation period, completeness of adverse-event collection, or detailed event definitions. The numbers also do not establish that events were impossible or that an intervention has no safety risks.

Deaths are marked null for both groups. Death counts are therefore not reported in the registry record; null should not be read as a reported zero. The healthy-subject group does not appear in the adverse-event group figures described in the record. These safety counts provide limited descriptive information and do not replace a complete safety analysis.

12. What the Result Does, and Does Not, Mean

The record establishes that a completed phase 4 study was registered to examine atorvastatin in relation to circulating endothelial progenitor cells among people with ischemic and nonischemic cardiomyopathy. It identifies a continuous primary outcome, a measurement approach, and a Baseline - 6 months timeframe. It also states an MRI-related aim in its brief summary. These details clarify what the study sought to assess.

They do not establish what the study found. The numerical primary outcome, its variability, group-specific results, and inferential statistics are not reported in the registry record. The MRI outcome results are also not reported in the registry record. It is therefore not possible to say whether EPC measures changed, whether groups differed, how large any observed change was, or how precisely an effect was estimated. The stated study purpose should not be mistaken for a result.

The design further limits causal interpretation. Allocation was non-randomized and masking was listed as none. In general, an observed difference in a non-randomized study may reflect differences between groups as well as any treatment-associated change. The group-assignment process, baseline comparability, adjustment methods, and analysis population are not reported in the registry record. The healthy-subject group is listed, but the record does not establish it as a suitable control for a treatment comparison.

The adverse-event information is similarly limited. The registry lists zero serious and zero other adverse events among the reported at-risk counts for the two cardiomyopathy groups, but the counts are small and the safety follow-up details are not reported. Death data are null rather than reported as zero.

In general, a trial result is best understood through its estimate, uncertainty, design, and completeness of follow-up together. Here, the design and endpoint can be described, but the effect estimate and key analysis details are absent. The appropriate statistical interpretation is therefore that the posted record does not allow a quantitative judgment about the primary outcome or the MRI aim.

13. Why This Trial Matters Statistically

This trial illustrates why a registry description and a numerical result answer different questions. The record clearly identifies a biological endpoint, a laboratory measurement approach, and the intended observation period. Those details let readers understand what was to be measured. Without the result values, however, the central statistical questions about direction, magnitude, and precision remain unanswered.

It also highlights the importance of design when interpreting comparisons. The record identifies non-randomized allocation and no masking. In general, these design features affect how confidently an observed difference can be attributed to treatment, because assignment may be related to participant characteristics and knowledge of treatment may influence aspects of study conduct. The registry does not describe how groups were formed or how possible differences were addressed.

The study further distinguishes the stated primary endpoint from the broader purpose. The primary endpoint is EPC change, whereas the brief summary also mentions MRI assessment of damaged heart areas. Clear endpoint definitions and numerical results are necessary to know which question was analyzed and what evidence the analysis supports. The detailed MRI outcome information is not reported in the registry record.

From a biostatistical perspective, the absence of outcome estimates and uncertainty illustrates why a study’s completion status, enrollment count, or planned analysis cannot substitute for results. The record lists enrollment of 9, but the number contributing data to the primary analysis is not reported. It also describes a planning illustration based on an observed effect, while distinguishing it from the actual trial design. Such planning information is not a result and is not observed power.

The case therefore matters as an example of disciplined interpretation: descriptions of aims, procedures, and design can be reported, while unanswered numerical questions must remain unanswered. The registry record supports an account of what was planned and how the endpoint was described, but not a conclusion about the endpoint’s observed behavior.

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 available record does not include numerical primary endpoint results. Means, standard deviations, group contrasts, confidence intervals, and p-values are not reported in the registry record. Without these values, neither the size nor the precision of an EPC change can be evaluated.

The study is non-randomized and unmasked. The process used to assign participants to groups and the baseline characteristics of those groups are not reported in the registry record. As a result, comparability and the potential for confounding cannot be assessed. The role of the healthy-subject group in the primary analysis is also not reported in the registry record.

The registry lists enrollment of 9, but does not report the number with complete endpoint measurements, the analysis population, participant withdrawals, or the handling of missing observations. The duration and completeness of safety follow-up are not reported in the registry record. These omissions limit assessment of both outcome completeness and adverse-event ascertainment.

The brief summary refers to MRI assessment, but the MRI endpoint definition and results are not reported in the registry record. Although two outcome measures and one analysis are listed, the other outcome’s details and the statistical analysis plan are not described. Multiplicity handling, covariate adjustment, model assumptions, and any interim analyses are not reported in the registry record.

The record describes a planning illustration based on an observed effect but does not report its numerical outputs or the observed effect magnitude. This illustration is explicitly separate from the trial’s own design and cannot clarify the adequacy of the actual enrollment. Taken together, these limitations mean the registry supports a descriptive account of the study but not a quantitative evaluation of its findings.

15. Related Tutorials

16. Related Statistical Calculators

17. Sources

• ClinicalTrials.gov: Statin Therapy for Ischemic and Nonischemic Cardiomyopathy — NCT00701220.
• Registry record last updated 2023-07-18; status last verified 2023-06.
• Results first posted 2023-07-18.
• 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.

18. Record Summary

The registry record describes a completed phase 4, non-randomized, unmasked, parallel study with enrollment of 9. The listed groups include people with ischemic cardiomyopathy, people with nonischemic cardiomyopathy, and healthy subjects. Atorvastatin Calcium is the listed drug intervention.

The primary outcome is change in endothelial progenitor cells, measured as percentage of EPCs from Baseline - 6 months, with mean and standard deviation identified as summary measures. The laboratory description uses ALDEFLOUR labeling and Facscan analysis. The brief summary also mentions MRI assessment of damaged heart areas.

Numerical primary and MRI results, analysis-population details, missing-data methods, and the statistical plan are not reported in the registry record. The adverse-event entries list zero serious and zero other events in the two reported cardiomyopathy groups; death counts are null. The record supports description of the study design and intended measurements, but not a quantitative judgment of the outcomes.