4045 participants were retained for analysis. 3640 participants were married and the remaining 405 were censored. The mixed effects Cox regression model of marriage indicated that the variance component associated with the additive genetic random effect was 0.30 (SD = 0.55). In the context of Cox mixed-effects models, this effect does not have a direct conversion to estimate heritability. Rather, this component is exponentiated and interpreted as the relative risk of marriage attributable to additive genetic factors for individuals who are one standard deviation above or below the baseline level of risk (Pankratz et al., 2005). This corresponds to a relative risk of marriage that is 1.73 (i.e., exp(0.55) = 1.73) higher or lower than the baseline hazard rate, meaning that the individual-specific relative risk of marriage attributable to genetic relatedness for subjects who are one standard deviation above or below the baseline level of risk was 1.73 times larger or smaller than the average likelihood of marriage. Said another way, one’s individual likelihood of marriage increases when they are genetically more similar to others who are married, and decreases
