Animals assigned by chance to the different study groups is called ___.

Randomization is a fundamental concept in experimental design, particularly in the context of clinical trials and animal research. It refers to the process of assigning animals to different study groups in a manner that is determined by chance, rather than through any systematic or biased method. This technique is essential for minimizing selection bias and ensuring that each group is comparable at the outset of the study.

By using randomization, researchers can help ensure that the effects observed in the study are due to the treatments being administered rather than pre-existing differences between the groups. This increases the validity of the conclusions drawn from the research and allows for a more accurate assessment of the treatment’s efficacy.

While stratification involves dividing a population into subgroups before random assignment, it does not represent the random assignment process itself. Blinding refers to keeping study participants or administrators unaware of which treatments participants receive, which helps to prevent bias in treatment effects. Sampling, on the other hand, pertains to the process of selecting a representative subset from a larger population, but it does not involve the specific assignment of individuals to study groups. Thus, randomization is the accurate term to describe the chance assignment of animals to different study groups in a research context.