A group allocation design is also known as cluster randomization.

A group allocation design is also known as cluster randomization.

• A. Block Randomization
• B. Crossover Randomization
• C. Cluster Randomization
• D. Factorial Randomization

Answer: (C)

Grouping units to receive different interventions is the hallmark of cluster randomization. When the randomization happens at the level of clusters—such as entire clinics, schools, or communities—rather than at the level of individual participants, you’re implementing a group allocation design. This approach is used because the intervention is often delivered to a whole group or to prevent contamination between participants in close contact, making it more practical and reflective of real-world implementation. That’s why this option is the best fit: the term describes randomizing groups rather than individuals. Other methods focus on individuals or specific design features—like ensuring balance within blocks, having the same person experience multiple treatments, or assigning participants to combinations of factors—so they don’t capture the idea of randomizing by clusters.

Grouping units to receive different interventions is the hallmark of cluster randomization. When the randomization happens at the level of clusters—such as entire clinics, schools, or communities—rather than at the level of individual participants, you’re implementing a group allocation design. This approach is used because the intervention is often delivered to a whole group or to prevent contamination between participants in close contact, making it more practical and reflective of real-world implementation.

That’s why this option is the best fit: the term describes randomizing groups rather than individuals. Other methods focus on individuals or specific design features—like ensuring balance within blocks, having the same person experience multiple treatments, or assigning participants to combinations of factors—so they don’t capture the idea of randomizing by clusters.