Severity of Substance Use Disorder: Utility as an Outcome in Clinical Settings.

Background: Some authors have pointed out the usefulness of the levels of substance use disorder (SUD) as a treatment outcome. However, in order to use this variable as an outcome measure, its impact needs to be addressed within a clinical context. The aim of this study was to analyze the sensitivity of SUD levels as a measure for detecting reliable changes and to make a comparison between the changes in SUD levels detected when using the number of criteria fulfilled and when using the reliable change index (RCI).
Methods: The sample consisted of 206 (106 in follow-up) patients diagnosed with abuse/dependence on alcohol and cocaine, according to DSM-IV criteria. The Substance Dependence Severity Scale for DSM-5 was used to determine current alcohol use disorder (AUD) and cocaine use disorder (CUD). Number of DSM-5 criteria fulfilled and RCI were used to determine the change in SUD levels.
Results: No association was found between adherence to/abandonment of treatment and AUD severity levels (χ ²  = 7.029, p = 0.071) or CUD severity levels (χ ²  = 2.044, p = 0.413). Statistical significant differences for levels of AUD (z = -3.870, p = 0.000) and CUD (z = -5.382, p = 0.000) were found between baseline assessment and follow-up. According to the number of DSM-5 criteria and RCI, the Kappa coefficient for the change in patient status (improved, worsened, or no change) was k = 0.61 for alcohol patients and k = 0.64 for cocaine patients. The "mild" category showed the greatest inconsistency between both procedures.
Conclusions: Levels of SUD are sensitive to the impact of treatment as measured by the difference between the baseline assessment and 3-month follow-up. However, conclusions differ according to whether the DSM-5 criteria or the RCI is applied.
(© 2019 by the Research Society on Alcoholism.)