Finally, stressful life events were assessed via a structured interview administered to each twin52. Our analyses are limited to what are referred to as “independent” life events53. That is, these events are largely independent of the individual's behavior (e.g., parent lost a job) as opposed to being in some way dependent on the respondent's behavior (e.g., failed a class). The stressful life events measure for this analysis was a tally of 18 life events covering the domains of parental divorce and discord as well as family money, legal, and mental health problems. As these events should be concordant for members of a twin pair, the correlation between twin reports provides an estimate of reliability (r = .81; inter-rater reliability was .89).
