Managed care plans are obligated by payers to constrain costs. These are insisted upon by payers. Many payers have mandated use of capitation to limit costs. Manage care organizations use managed networks of providers with discounted fee structures to help restrain costs. Professionals do not like managed networks and discouunted fees which payers are insisting upon.
Medical necessity is used for both access and service continuation.
Prior to managed care, private plans typically provided 30 days of inpatient hospitalization and 20 visits of psychotherapy a year. Insurance companies merely paid up to the limit. If a person had a serious mental illness they were then transferred to the public mental health system where state hospitals and community clinics with waiting lists dominated. Thus services were rationed within a two-class system. Some public mental health systems developed community support systems which attempted to coordinate care across social support systems for the clientele admitted to the public system.