Extending the evidence hierarchy to enhance evidence-based practice for substance use disorders

Purpose: This paper examines the evidence-based practice (EBP) movement in the context of the developmental status of theory, research and practice on substance use disorders. Scope: Hierarchical views that favor randomized controlled trials (RCTs) over other forms of evidence are reviewed, and the benefits and limitations of RCTs are considered as they intersect with contemporary issues in the field. Findings: RCTs with lengthy follow-up intervals comprise an important piece of the relevant evidence base, especially for establishing treatment efficacy, but their continued centrality as the 'gold standard' of evidence for informing substance abuse practice is questioned. Conclusions: Given the status of knowledge, advances in science and practice will probably come from longitudinal studies of the changeable course of addictive behaviors and processes over long time frames and that investigate linkages with treatment selection factors and other surrounding contextual variables that also change through time. Benefits of evidentiary pluralism for advancing an interdisciplinary approach to research and practice are considered.