Preliminary Study of the Effectiveness of the GUIA Assertive Community Treatment Program for the Care of Young, Highly Complex Mental Health Patients.

This study presents a preliminary evaluation of the effectiveness of the GUIA Team's flexible Assertive Community Treatment (ACT) program implemented in Spain, designed for adolescents and young adults with complex mental health conditions. The program addresses fragmented care by coordinating multiple service sectors. Retrospective observational pre-post study with 42 participants aged 14-25 years, assessing treatment adherence, clinical symptoms, hospital service utilization and global functioning. Findings demonstrate a significant reduction in psychiatric emergency visits and involuntary hospitalizations, along with objective improvements in clinical symptomatology and overall functioning, particularly with longer intervention. Treatment adherence was high and outcomes were consistent across a heterogeneous sample, irrespective of primary diagnoses or demographic characteristics. These findings suggest that diagnostic categories alone are limited in predicting outcomes in complex cases, underscoring the importance of functional and recovery oriented models. The study supports the feasibility and clinical value of a flexible ACT model adapted for youth, emphasizing sustained, multidisciplinary and individualized interventions in the patient's natural environment.