Medical Service Study Areas (MSSAs) are sub-city and sub-county geographical units used to organize and display population, demographic and physician data. It helps to determine areas of unmet priority need for primary care family physicians and geographical rural areas where unmet priority need for medical services exist. MSSAs are recognized by the U.S. Health Resources and Services Administration, Bureau of Health Professions’ Office of Shortage Designation as rational service areas for purposes of designating Health Professional Shortage Areas (HPSAs), and Medically Underserved Areas and Medically Underserved Populations (MUAs/MUPs). The MSSAs incorporate the U.S. Census total population, socioeconomic and demographic data and are updated with each decadal census.
Office of Statewide Health Planning and Development provides updated data for each County’s MSSAs to the County and Communities. Each MSSA is composed of one or more complete census tracts. MSSAs will not cross county lines. All population centers within the MSSA are within 30 minutes travel time to the largest population center. Urban MSSA has Population range 75,000 to 125,000 and reflects recognized community and neighborhood boundaries. Rural MSSA has a population density of less than 250 persons per square mile and population center does not exceed 50,000. Frontier MSSA has a population density of less than 11 persons per square mile. The California Health and Human Services Agency coordinates the administration of state and federal programs for public health, health care services, social services, public assistance, health planning and licensing, and rehabilitation. These programs touch the lives of millions of California’s most needy and vulnerable residents. The Agency is responsible for balancing the twin imperatives of providing access to essential health and human services for California’s most disadvantaged and at-risk residents and managing and controlling costs.