We estimated the reliability of LTH-AD to be moderate (κ = 0.54). Furthermore, the short-term reliability of AD in the current sample was estimated to be κ = 0.72 (Kendler and Prescott, 2006). This is in accord with previous studies that have found AD to be among the more reliable common psychiatric disorders (Rice et al., 1986, 1992; Wittchen, 1994), with good short-term reliability (κ = 0.71 to 0.75) (Chatterji et al., 1997; Grant et al., 1995; Young-Wolff et al., 2009) and moderate long-term reliability (κ = 0.56 to 0.61) (Demallie et al., 1995; Slutske et al., 1998), and indicates that LTH-AD can be measured in population-based samples with a moderate reliability.
