Impact of Psychiatric Rehabilitation on Chronicity and Health Outcomes in Mental Disorders: A Quasi-Experimental Study

<b>Background/Objectives</b>: People suffering from mental illnesses are more likely to experience adverse social and health outcomes. Various interventions have been shown to help people with mental illness achieve better results in terms of symptom reduction, functional status, and quality of life. Psychiatric rehabilitation interventions integrate evidence-based practices, promising approaches, and emerging methods that can be effectively implemented to enhance health outcomes in this population. This study aims to examine whether the rehabilitative treatment provided to a group of patients with mental illness leads to improvements in health outcomes and psychiatric symptomatology. <b>Methods</b>: This study employed a retrospective quasi-experimental design. Data were collected between 2023 and 2025 within the Partial Hospitalization Program of the Psychiatry and Mental Health Service of Soria (Spain). The sample consisted of 58 participants who received rehabilitative treatment in this setting. Data were collected at the time of patients' admission and at discharge. Gender, age, psychiatric diagnosis according to ICD-10, and the average length of stay in the rehabilitation program were assessed. The questionnaires administered were psychometrically validated scales related to heteroaggressiveness, perceived quality of life, global functioning, attitudes toward medication, and the risk of suicide. <b>Results</b>: A significant improvement was observed in the Global Assessment of Functioning (GAF) Scale (<i>t</i> = -7.1, <i>p</i> < 0.001), with mean scores increasing from 42.17 at admission to 69.13 at discharge. Additionally, reductions in suicidal risk and hetero-aggressive behavior were noted, alongside improvements in quality of life and treatment adherence. <b>Conclusions</b>: The findings highlight the effectiveness of implementing activities and programs focused on psychiatric rehabilitation processes to promote positive health outcomes. Future research directions and practical implications are discussed to support the continued development and optimization of psychiatric rehabilitation programs.