# Clustered Treatment Assignments and Sensitivity to Unmeasured Biases in Observational Studies

@article{Hansen2014ClusteredTA, title={Clustered Treatment Assignments and Sensitivity to Unmeasured Biases in Observational Studies}, author={B. Hansen and P. Rosenbaum and Dylan S. Small}, journal={Journal of the American Statistical Association}, year={2014}, volume={109}, pages={133 - 144} }

Clustered treatment assignment occurs when individuals are grouped into clusters prior to treatment and whole clusters, not individuals, are assigned to treatment or control. In randomized trials, clustered assignments may be required because the treatment must be applied to all children in a classroom, or to all patients at a clinic, or to all radio listeners in the same media market. The most common cluster randomized design pairs 2S clusters into S pairs based on similar pretreatment… Expand

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