The attention problems (AP) subscale of the YASR consists of seven items (see Table 2) with three ordered response categories (0 = Not true, 1 = Somewhat or Sometimes True, 2 = Very True or Often True). In children, sum scores typically show a high heritability with a significant non-additive genetic component (Rietveld et al. 2004). In young adults, AP sum scores also showed heritability (40%), but no non-additive genetic component (Van den Berg et al. 2006c). Table 2Items of the attention problems subscale of the young adult self-report (YASR; Achenbach 1997)ItemDescription1I act too young for my age2I have trouble concentrating or paying attention3I daydream a lot 4My school work or job performance is poor5I am too dependent on others 6I fail to finish things I should do7My behaviour is irresponsible
