A NARRATIVE REVIEW OF SAMPLE SIZE ESTIMATION FOR QUANTITATIVE EPIDEMIOLOGICAL AND CLINICAL STUDY DESIGNS

Area of Science:

• Biostatistics
• Epidemiology
• Clinical Research

Background:

• Sample size estimation is a critical yet frequently challenging aspect of research design.
• Researchers often seek guidance from biostatisticians to determine appropriate sample sizes.
• Inadequate sample size can compromise study validity and the generalizability of findings.

Purpose of the Study:

• To provide a simplified overview of sample size estimation methods for quantitative research.
• To explain fundamental principles and common techniques in sample size calculation.
• To offer accessible formulas for various epidemiological and clinical study designs.

Main Methods:

• Discussion of key statistical concepts: outcome variable, confidence level, statistical power, and effect size.
• Presentation of straightforward sample size formulas for common study designs.
• Explanation of principles guiding sample size determination.

Main Results:

• Researchers can utilize the provided simplified formulas and explanations to estimate sample sizes.
• The article facilitates understanding of the statistical underpinnings of sample size calculation.
• Empowers researchers to determine sample sizes appropriate for their specific study design and objectives.

Conclusions:

• The article equips researchers with practical tools for accurate sample size estimation.
• Adherence to these principles enhances the robustness and reliability of research findings.
• Proper sample size calculation is essential for ensuring the generalizability of results to the target population.