We also compared the two diagnostic systems on the basis of three- and four-level diagnoses. For DSM-IV, the levels were (I) neither abuse nor dependence, (II) abuse without dependence, and (III) dependence with or without abuse. For DSM-5, the levels were (I) no SUD, (II) mild SUD, (III) moderate SUD, and (IV) severe SUD. Collapsing levels III and IV of the DSM-5 classification yields a three-level diagnosis, which showed a high rate of agreement with the DSM-IV three-level diagnosis: the kappa statistics for alcohol, cocaine, opioids, and cannabis were 0.84, 0.94, 0.97, and 0.80, respectively.
