Which of the following statements about using a statistical analysis to justify animal numbers is TRUE?

Utilizing statistical analysis to justify animal numbers is essential because it helps researchers determine the minimum number of animals needed to obtain reliable and valid results while minimizing the use of animals. This approach aligns with ethical principles in animal research, specifically the "3Rs" (Reduce, Replace, and Refine), which promote reducing the number of animals used to the smallest number that will still yield valid results.

Employing statistical methods ensures that studies are adequately powered to detect meaningful effects, which contributes to the scientific rigor and the reproducibility of research findings. This methodology supports the ethical obligation to use animals responsibly and to ensure that studies are not underpowered or overpowered, both of which can lead to scientifically invalid conclusions.

On the other hand, the assertion that statistical analysis is optional does not reflect current ethical standards in animal research, and claiming that it is only needed for large studies overlooks the importance of statistical rigor in all types of studies. Moreover, stating that statistical analysis is irrelevant contradicts the fundamental principles of conducting scientifically valid and ethical research. The recognition of the importance of statistical justification shows a commitment to both ethical research practices and scientific integrity.