Although all causal complements of the exposure of interest are effect modifiers in the SCC framework, when exploring effect modification we explicitly name the causal complement that is the effect modifier of interest, as shown in the SCC model in Figure 6B (i.e., in the right-most sufficient cause, APOE ε4 is the effect modifier of explicit interest and is expressed in the sufficient cause in addition to Z1b, which represents all other causal complements low education works with to cause dementia). This evidence concerns the gene APOE and dementia.