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ARE of 
relative to
. Figures in the
left column show ARE vs. baseline risk 
with the risk
difference 
; Figures in the right column
show ARE vs. risk difference 
with the baseline risk
. There are no time effects
(
) in the first row, very small
time effects in the second row (
), and moderate time
effects in the third row (
). The number of clusters
, the number of steps
, the cluster size
, and 
.
