Sample sizes per group for 80% power with a one-tailed test of independent proportions

The table below gives the sample size to get 80% power required in each group where the group proportions are as in the row and column for a one-tailed type I error of 5%.

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

0.1

158

50

27

17

12

9

7

5

0.2

232

66

32

19

13

9

7

0.3

282

75

35

20

13

9

0.4

307

78

35

19

12

0.5

307

75

32

17

0.6

282

66

27

0.7

232

50

0.8

158