Ace the 2025 CCRA Exam – Get Ready to Rock Your Research Career!

The design of a clinical study where two treatments are administered to separate groups is known as a parallel design. In this type of study, participants are randomly assigned to different treatment arms, which ensures that each group receives a distinct treatment while maintaining the integrity of the study's comparison. This design is particularly effective for comparing the efficacy and safety of two interventions as it allows researchers to evaluate the outcomes independently within each group.

In a parallel design, the separate groups are treated independently, making it easier to analyze the effects of each treatment without the complications that can arise from participants experiencing multiple treatments, as is the case in a crossover design. By using randomization, the study can minimize biases and confounding factors, thus enhancing the reliability of the results.

Adaptive designs and randomized designs can also involve elements of grouping and treatment allocation; however, they are broader terms. Adaptive designs involve changing study parameters based on interim results, and randomized designs refer to the process of assigning participants to groups unpredictably, which can occur in various study formats, including parallel and crossover designs. Therefore, parallel design specifically addresses the situation where distinct groups receive separate treatments, making it the appropriate answer.