“…For example, it is unclear if such thinking implies (a) simple additivity (i.e, the degree of stress and the loading of the diathesis summate, with virtually any complementary combination of sufficient magnitude producing the disorder), (b) simple interaction (ije., a synergism between the diathesis and stress that yields an effect beyond their combined separate effects; Rothman, 1976); or (c) complex interaction (i£., various combinations of additivity and synergism, such as postulating threshold effects for the diathesis). (e.g, Whytt, 1765), which was more recently promoted by Slater and Slater (1944), and is congruent with many contemporary descriptions of diathesis-stress theory (Abramson et al, 1989;Davison & Neal, 1990;Zubin & Spring, 1977) and research (Pollitt, 1972;Stenstedt, 1952).…”