Practical considerations and methods for determining sample size to estimate a population mean: a narrative review

Area of Science:

• Biostatistics
• Research Methodology

Background:

• Sample size determination is critical for research validity and precision.
• Many researchers overlook estimation-based sample size formulas, focusing instead on hypothesis testing.
• The classical sample size formula for population mean estimation is essential but often neglected.

Purpose of the Study:

• To review the concept, rationale, and application of the sample size formula for population mean estimation.
• To provide guidance on the theoretical foundation, calculation steps, and appropriate use of this formula.
• To emphasize the importance of this formula in contemporary research for improving study design and credibility.

Main Methods:

• Review of the classical sample size formula for estimating a population mean.
• Explanation of theoretical underpinnings and practical calculation steps.
• Discussion of appropriate contexts for its application in descriptive and estimation studies.

Main Results:

• The paper clarifies the concept and rationale behind the sample size formula for mean estimation.
• It details the practical steps for calculating the required sample size.
• It underscores the formula's relevance across diverse research settings.

Conclusions:

• Proper sample size planning using this formula enhances research design validity.
• Accurate sample size calculation is crucial for improving the quality and credibility of scientific investigations.
• This formula remains a highly relevant and essential tool for researchers focusing on estimation.