. 2020 Apr 14;93:106000. doi: 10.1016/j.cct.2020.106000

Table 3.

Sample size estimates for the six planned analyses, assuming medium effects for the causal paths (a and b) and at least a medium interaction effect (f2) for the three planned Treatment Condition X Mediation effects tests.

Alpha	Power	Effect size path a	Effect size path b	Interaction effects	n-required/n-planned
0.050	0.80	Medium (r = 0.30)	Medium (r = 0.30)		109/240
0.025	0.80	Medium (r = 0.30)	Medium (r = 0.30)		129/240
0.017	0.80	Medium (r = 0.30)	Medium (r = 0.30)		140/240
0.013	0.80			Medium (f² = 0.15)	93/240
0.010	0.80			Medium (f² = 0.15)	98/240
0.008	0.80			Medium (f² = 0.15)	102/240