make them go away); and 3) were classified as DSM-IV alcohol dependent. The medication requirement was included in order to more closely approximate the “severe” withdrawal of Koehnke et al. (Koehnke et al., 2002). Subjects were coded as unaffected if they were classified as DSM-IV dependent but did not experience any of the nine symptoms. All other subjects were considered unknown (Table 1). This phenotype is referred to as severe withdrawal.
