What is the primary purpose of randomization in clinical trials?

The primary purpose of randomization in clinical trials is to assign trial subjects to treatment or control groups randomly. This random assignment is essential for minimizing bias in the treatment allocation process, thereby ensuring that the groups being compared are as similar as possible in all respects except for the treatment being tested.

By randomly assigning participants, researchers can help protect against other confounding factors that could influence the outcomes of the trial, such as age, sex, underlying health conditions, or other characteristics. This process leads to more reliable and valid conclusions about the treatment's efficacy and safety since it allows for the effects of the treatments to be observed under similar conditions.

In contrast, other options do not accurately capture the main goal of randomization. While a larger sample size can enhance statistical power, it is not the purpose of randomization itself. Randomization does not guarantee that patients receive the standard treatment; rather, it allows for a fair comparison between the new treatment and standard or placebo treatments. Additionally, randomization does not eliminate the need for a control group; it actually facilitates having an appropriate control group by ensuring random assignment, which allows for meaningful comparisons.