Statistical power and sample size calculations: A primer for pediatric surgeons

Area of Science:

• Surgical Research Methodology
• Biostatistics in Medicine

Background:

• Sample size determination is essential for robust research, grant applications, and scientific publications.
• Surgeons often lack practical knowledge for correct statistical power calculations.
• Accurate sample size is vital for interpreting and validating research findings.

Purpose of the Study:

• To provide pediatric surgeons with a clear strategy for sample size calculation.
• To enable the detection of clinically meaningful effects in surgical studies.
• To enhance the quality and interpretability of surgical research.

Main Methods:

• A 5-step approach for sample size justification and power analysis is presented.
• Steps include defining outcomes, effect size, desired power, statistical tests, and calculations.
• The process culminates in writing a formal power and sample size statement.

Main Results:

• The article outlines a practical framework for sample size estimation in surgical research.
• Illustrative examples using surgical research scenarios are provided.
• The methodology facilitates accurate sample size determination for various study designs.

Conclusions:

• Improved understanding of sample size and statistical power will elevate surgical research quality.
• This primer empowers pediatric surgeons to determine appropriate sample sizes for their studies.
• Justifying sample size via power calculations leads to more meaningful inferences in pediatric surgery research.