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Table 2 The power for expected number of events required in the control group for a specific relative rate, θ, for the different scenarios as in Table1 using eqn ( 7)

From: Sample size calculation for multicentre efficacy trials of blood-stage malaria antigens

Scenarios Sample size E(n) Alpha zα/2 θ Ec zβ Power
Scenario 1 1,840 339 0.05 1.96 0.7 199.412 1.2892 0.90
  1,288 237 0.05 1.96 0.7 139.412 0.75677 0.78
Scenario 2 1,840 322 0.05 1.96 0.7 189.412 1.20669 0.89
  1,288 226 0.05 1.96 0.7 132.941 0.69297 0.76
Scenario 3 1,840 237 0.05 1.96 0.7 139.412 0.75677 0.78
  1,288 166 0.05 1.96 0.7 97.6471 0.3137 0.62
Scenario 4 1,840 168 0.05 1.96 0.7 98.8235 0.32736 0.63
  1,288 117 0.05 1.96 0.7 68.8235 -0.05114 0.48
Scenario 5 1,380 237 0.05 1.96 0.7 139.412 0.75677 0.78
  966 166 0.05 1.96 0.7 97.6471 0.3137 0.62