Application of Self-Determination Theory to Substance Use and Its Treatment: A Scoping Review of the Literature.

Background: Self-determination theory (SDT) may provide important insights for understanding substance misuse and treatment outcomes. However, to date, the literature applying SDT to substance use and its treatment is varied and difficult to integrate. Methods: The authors searched psycINFO and PubMed on October 26th, 2021 to identify articles applying SDT to substance use and its treatment. Eligible studies were published in peer-reviewed articles in English, on adult populations (18+), and explicitly applied SDT to the context of substance use or its treatment. Results were categorized as studies applying SDT in non-treatment or treatment settings and were synthesized within these categories by substance(s) of focus, primary outcome(s), component(s) of SDT utilized, and relevant findings. Results: The search revealed 38 articles applying SDT in non-treatment (k = 16) and treatment (k = 22) settings. Causality orientations and the basic psychological needs were the most frequently studied components of SDT. Studies that applied SDT in non-treatment settings placed a greater emphasis on causality orientations, whereas treatment studies more frequently targeted or measured basic psychological needs. Conclusions: SDT constructs consistently predicted both substance misuse and treatment outcomes in a theoretically consistent manner, however, several important gaps remain and opportunities for future research are discussed.