Mixed Methods in Substance Use Disorder Research: A Critical Essay

Mixed methods research (MMR) has become increasingly important in substance use disorder (SUD) research because it combines quantitative and qualitative approaches to capture the biological, psychological, social, and structural dimensions of addiction. However, the value of MMR depends on effectively integrating these approaches throughout the research process. This critical review examines major integration challenges in mixed-methods SUD research and identifies methodological strategies to address them. The review also examines how power asymmetries and researcher positionality shape integration decisions and how longitudinal designs introduce distinct integration challenges. Collectively, these approaches enhance the credibility, coherence, and interpretability of integrated findings. The review argues that integration should be treated not as a final stage of analysis but as a methodological commitment embedded throughout study design, sampling, data collection, analysis, and reporting. By synthesizing current methodological guidance, this essay seeks to advance rigorous mixed-methods research that informs evidence-based policies and interventions for substance use disorders.