One important variable that may help to account for the different results in the different stressor groups is the variation in methods between the studies within each group69. Within the childhood maltreatment and specific stressors groups, the methodological details of the primary studies were generally similar. In contrast, there is marked variation in methods between SLE studies. First the studies vary substantially in what was considered a stressful life event. In addition, the method through which stressful life events were measured varied substantially between studies in this group. Some studies measured stress through one-time self-report life events checklists while others employed repeated in-person interviews and life history calendars1, 70. It is noteworthy that almost all of the studies that failed to identify an effect of genetic moderation used self-report checklists (Table 1). In addition, some studies asked subjects about SLEs and depressive episodes that occurred decades earlier while others assessed SLEs and depressive episodes soon after they occurred30, 71. As a result, the extent to which recall bias affected the findings of these studies varied substantially between the studies. Given
