To formally test the interaction effect, we conducted a logistic regression which included genotype (AA/AG versus GG), abuse (exposed/unexposed) and their interaction, as well as age. As shown in Table 3, the interaction odds-ratio [O.R.= 0.31, 95% C.I. 0.12–0.79] confirmed that in carriers of the minor allele (AA/AG) the effect of childhood physical abuse on anhedonia was attenuated.
