Table 2. Sample size calculation.

Effect size (dz)	Completed pairs needed, n	Recruits with 10% dropout, n	Recruits with 20% dropouts, n	Recruits with 30% dropouts, n
0.4	52	57	62	68
0.5	34	37	41	44
0.6	24	26	29	31
0.7	19	21	23	25
0.8	15	17	18	20