Cluster Randomized Controlled Trials: A Quick Update on Concepts and Types

Abstract

Cluster randomized controlled trials have certain complexities both at design and statistical
analysis stages of the experiment. Although, this experimental study approach offers solutions
in situations where it would be inappropriate to randomize individuals into treatment arms its
design and statistical analysis are not without certain unique challenges. Compared to individual
randomized controlled trials, very limited understanding of the design concepts in cluster
randomized controlled trials exists, this perhaps explain reasons it is not as popular as the
former. This short note presents a quick description of cluster randomized controlled trials with
a view to enhance capacity in its design, conduct and management. It will also provide students
and researchers with ready-made information necessary to make appropriate choices regarding
type of cluster randomized trials given a prevailing research environment.