This page provides an independent statistical analysis and educational interpretation of publicly reported results. ClinicalTrials.gov provides the official trial registry record.
1. Trial at a Glance
CALERIE was a completed clinical trial sponsored by Pennington Biomedical Research Center evaluating participant behavior and response after a 2-year intervention of calorie restriction.
| Feature | CALERIE |
|---|---|
| NCT ID | NCT00943215 |
| Status | COMPLETED |
| Sponsor | Pennington Biomedical Research Center |
| Sponsor type | OTHER |
| Condition | Excessive Diet Restriction |
| Enrollment | 42 |
2. Clinical Question
Population
Participants enrolled in the CALERIE study.
Intervention
A 2-year intervention of calorie restriction.
Comparator
The registry describes participant behavior and response after completing the intervention.
Primary Question
How participants behave and respond on their own after completing a 2-year intervention of calorie restriction.
3. Trial Design
Study Period
Start date: 2009-07
Primary completion date: 2015-02
Study Objective
Evaluation of participant behavior and response following completion of a calorie restriction intervention.
4. Endpoints
| Endpoint | Time Frame | Description |
|---|---|---|
| Calorie Restriction | 2-year | The purpose of this study is to gain knowledge about how participants behave and respond on their own after completing a 2-year intervention of calorie restriction. |
5. Planned Analysis
The ClinicalTrials.gov record lists the primary endpoint but does not report posted statistical analyses or outcome estimates.
For an endpoint describing response following an intervention over time, statistical analysis would typically depend on the specific outcome measurements collected. Continuous outcomes may commonly be summarized using descriptive statistics and compared using methods appropriate for repeated measurements, while categorical outcomes may require proportion-based analyses or regression models. The appropriate method depends on the prespecified analysis plan and measurement structure.
6. Statistical Methodology
Clinical trial analysis begins with clearly defining the population, intervention, comparison framework, endpoint definitions, and timing of assessment. CALERIE's registered primary endpoint focuses on participant behavior and response after a 2-year calorie restriction intervention.
The statistical method must match the type of endpoint collected, the timing of assessments, and the scientific question being addressed.
7. Statistical Methods Explained
How would a 2-year intervention endpoint typically be analyzed?
A 2-year endpoint may involve comparison of measurements collected before, during, and after the intervention. The analysis approach depends on whether outcomes are continuous, categorical, or time-dependent.
Why is the endpoint definition important?
The endpoint definition determines what statistical quantity is estimated. A clearly specified endpoint prevents changes in interpretation after observing results.
Why are repeated measurements important?
Measurements collected at multiple time points contain within-participant correlation. Statistical methods should account for this dependence when estimating changes over time.
Why can enrollment size affect interpretation?
The precision of estimated effects depends partly on the amount of information available. Smaller studies generally produce greater uncertainty around estimates.
8. Limitations
- The ClinicalTrials.gov record does not report posted statistical analyses or outcome estimates.
- The registry endpoint description alone does not provide numerical summaries of participant responses.
- The statistical method cannot be determined beyond general principles without additional analysis documentation.
9. Why This Trial Matters Statistically
CALERIE illustrates several important concepts in clinical trial methodology: defining clinically meaningful endpoints, aligning statistical methods with measurement structure, and interpreting intervention studies within the framework established before outcomes are observed.
| Concept | Application |
|---|---|
| Endpoint definition | Primary endpoint focused on calorie restriction response over a 2-year time frame. |
| Longitudinal assessment | Intervention studies may require methods that account for measurements over time. |
| Statistical interpretation | Results require estimates, uncertainty measures, and prespecified analyses. |
10. Sources
- ClinicalTrials.gov: CALERIE NCT00943215
Clinical Biostats Statistical Education
Explore statistical concepts used in clinical research, including endpoint selection, study design, and interpretation.