Abstract
Schizophrenia is a chronic mental disorder that affects an individual's emotional, cognitive, and behavioral well-being. Schizophrenia is characterized by poor treatment adherence, frequent relapses, and worsening symptoms, often leading to increased hospitalizations. Shared decision-making (SDM) has been proposed to enhance adherence by involving patients and their caregivers in collaborative treatment decisions. However, the impact of SDM on adherence, quality of life, and mental health outcomes remains uncertain. This review evaluates the effectiveness of SDM interventions on treatment adherence in individuals with schizophrenia and explores health-related outcomes, including quality of life, mental health, self-efficacy, trust in healthcare providers, and self-regard. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, PubMed, CINAHL, and Web of Science were systematically searched. Randomized controlled trials, quasi-experimental, and observational studies assessing adherence were included. Data extraction was performed by two independent reviewers, and study quality was assessed using the Cochrane Risk of Bias Tool. Eight studies involving 2,314 participants met the inclusion criteria. SDM interventions improved treatment adherence in most studies, with rates increasing by 9% (78% vs. 69%, p < 0.01). Quality of life, measured by the World Health Organization Quality-of-Life Scale Abbreviated Version (WHOQOL-BREF), improved by 8.03 points (p < 0.002), and self-esteem, measured via the Rosenberg Scale, increased by 4.06 points (p < 0.001). Additional outcomes included a statistically significant increase in problem-solving ability scores in the SDM group, from 106.68 to 124.00 (n = 29, p < 0.001), while perceived autonomy support, patient activation, and confidence in communicating with providers were also notably higher for SDM participants (p < 0.05). In conclusion, SDM interventions demonstrate significant benefits in improving treatment adherence, quality of life, and various psychological outcomes in individuals with schizophrenia. The findings suggest that SDM fosters greater patient engagement, enhances self-efficacy, and strengthens trust in healthcare providers, ultimately leading to better mental health management. Further research is needed to explore long-term effects and optimize SDM strategies for sustained adherence and improved patient outcomes.