The prevalence and incidence rates of psychiatric disorders are higher in people with autism spectrum disorders (ASD) than in the general population (Bradley, Summers, Hayley, & Bryson, 2004; Brereton, Tonge, & Einfeld, 2006; Clarke, Baxter, Perry, & Prasher, 1999; Ghaziuddin & Greden, 1998; Ghaziuddin, 2005; Ghaziuddin, Alessi, & Greden, 1995; Ghaziuddin, Tsai, & Ghaziuddin, 1992; Glenn, Bihm, & Lammers, 2003; Howlin, 1997, 2000; Howlin, Goode, Hutton, & Rutter, 2004; Lainhart, 1999; Leyfer et al., 2006; Matson & Nebel-Schwalm, 2007; Morgan, Roy, & Chance, 2003; Simonoff et al., 2008; Tsakanikos et al., 2006).