Table 4 Simulation input scenario values (total 1440 scenarios)

Number of clusters

c

3, 6, 12, 24

Cluster size

m

5, 10, 20, 30

Intervention effect

θ

0, 0.2, 0.5

ICC

ρ

0, 0.01, 0.05, 0.1, 0.2^a, 0.3^a

Ratio of individual variance between control and cluster trial arms

γ

0.25^a, 0.5, 1, 2, 4^a