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Updated: Jul 15, 2026
07:11
Sampling Soils in a Heterogeneous Research Plot
Published on: January 7, 2019
A method is presented to plan the required sample size when estimating regression-based reference limits
Carine A Bellera1, James A Hanley
1Department of Epidemiology and Biostatistics, McGill University, Montreal, Quebec, H2T 1H3, Canada. bellera@bergonie.org
Journal of Clinical Epidemiology
|May 12, 2007
Summary
Calculating sample sizes for regression-based reference limits is now simpler. A new formula provides transparent and user-friendly sample size projections for precise estimation in various health and science applications.
Area of Science:
- Biostatistics
- Anthropometry
- Clinical Chemistry
Background:
- Reference limits are crucial in various scientific fields, including medicine and behavioral sciences.
- Estimating reference limits as a function of age using regression is more efficient than separate estimations for age groups.
- Existing methods for determining sample sizes for regression-based reference limits lack transparency and user-friendliness.
Purpose of the Study:
- To develop a transparent and user-friendly method for calculating sample sizes for regression-based reference limits.
- To provide a simple formula for projecting required sample sizes based on desired precision.
Main Methods:
- A novel, intuitive formula was developed using margins of error.
- The formula facilitates sample size projection for various sampling strategies and precision levels.
Main Results:
- The study presents a straightforward formula for sample size calculation.
- Two illustrative examples demonstrate the application of the formula for estimating specific reference limits across different age distributions.
Conclusions:
- A simple and accessible formula is provided for determining the necessary sample size to estimate reference limits with a specified precision.
- The formula's adaptable structure readily incorporates diverse age-sampling strategies.
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