On September 11, 2001, a large-scale terrorist attack occurred in New York City (9/11) (Galea et al., 2002). Since then, studies have linked 9/11 exposure to adverse psychological outcomes, including depression, anxiety, and substance use disorders (Breslau et al., 2010; Henriksen et al., 2010; Neria et al., 2011; Perlman et al., 2011; Lucchini et al., 2012). Individuals directly impacted by 9/11 have been studied in depth (Welch et al., 2012). However, most of the US population experienced 9/11 indirectly, through relatives, friends, or media exposure, e.g., television news (Dougall et al., 2005). Such indirect 9/11 exposures were also associated with depression, anxiety, and problem drinking, particularly in vulnerable groups, such as those with prior psychiatric disorders (Lengua et al., 2005; Pollack et al., 2006; Otto et al., 2007; Holman et al., 2011; Barnes et al., 2012; Pietrzak et al., 2012). However, many aspects of the associations between 9/11 exposures and psychological outcomes remain unknown. Outstanding issues involve the relationships between direct and indirect 9/11 exposure, their impact on broad underlying dimensions of psychopathology rather than specific individual disorders, and whether
