Table 1

sample size calculations
Detectable difference in SBP between both the groups 80% power with an ICC of 0.02 90% power with an ICC of 0.02
Sample size required for individual randomization per arm Sample size required for cluster randomization per arm (DE = 2.98) Sample size required for cluster randomization with CV = 0.25 (DE = 3.1) Minimum no of clusters with a cluster size of 100 Sample size required for individual randomization per arm Sample size required for cluster randomization per arm (DE = 2.98) Sample size required for cluster randomization with CV = 0.25 (DE = 3.1) Minimum no of clusters with a cluster size of 100
4 mm of Hg 374 1115 1160 24 500 1490 1550 32
5 mm of Hg 239 713 741 16 320 954 992 20
6 mm of Hg 166 495 515 12 222 622 689 14

ICC = Intra Cluster correlation; DE = design effect; CV = coefficient of variation.

Anchala et al.

Anchala et al. BMC Public Health 2012 12:393   doi:10.1186/1471-2458-12-393

Open Data