Reshaping youth mental health care for optimal system-level outcomes: A dynamic modelling analysis.

Despite the critical role of effective treatment in limiting the adverse socioeconomic and health impacts of youth mental disorders, investment in mental health services is widely recognised to be insufficient to meet current demand for care. Using a dynamic model of resource-constrained services provision (constant total expenditure), we assessed the potential for improving mental health care outcomes for young people (aged 12-25 years) through changes in services system composition (i.e., the division of total services capacity between primary care services and specialised services) and policies for managing initial access to specialised treatment. Model analysis indicates that services delivery reforms facilitating direct engagement with specialised care, irrespective of clinical stage, are capable of significantly improving system-level (aggregate) outcomes, reducing total illness progression and disengagement from services, and increasing total treatment-mediated recovery. Restricting the ability of young people with relatively mild mental health problems to access specialised care (an explicit aim of stepped care models) effectively constrains the capacity of specialised services to promote recovery and prevent illness progression (both of which are more probable at earlier clinical stages), and does not make best use of available resources; better system-level outcomes are achieved when young people receive more effective, specialised treatment as early as possible. Provided that young people are not restricted to accessing specialised care only via primary care services, progression and disengagement decline as the proportion of mental health care expenditure allocated to specialised services increases, while the optimal proportion of young people directly accessing specialised care approaches a value of 1, suggesting that the largest improvements in services system performance are likely to be achieved by expanding specialised services capacity with the aim of providing all young people presenting for care with direct access to specialised treatment.