The 2007 MSSA Detail layer (developed during July 2009 - July 2010) is an update to the 2005 version. The 2000 Medical Service Study Area (MSSA) Census Tract Detail polygon layer represents all California census tract boundaries used in the construction of the 2000 MSSA Boundaries. Each of the state's 7,049 census tracts was assigned to a medical service study area, as identified in this data layer. The 2000 MSSA Census Tract Detail data is aggregated by OSHPD, to create the 2000 MSSA data layer. This layer is part of the Healthcare Atlas of California. The 2007 MSSA Detail layer (developed during July 2009 - July 2010) was developed to update fields affected by population change. The Claritas 2007 population data pertaining to total, group quarter, race, ethnicity, and age was used in the update. Some geometry updates were also included in this version. In July of 2010 updates were made to the poverty data to correct a miscalculation of poverty percentages and to remove "2007" from field names. The 2000 MSSA Census Tract Detail map layer was developed to support geographic information systems (GIS) applications, representing 2000 census tract geography that is the foundation of 2000 medical service study area (MSSA) boundaries. InfoUSA, U.S. Census Bureau, and California Office of Statewide Health Planning and Development. (2007). Medical Service Study Areas, Census Tract Detail. California, 2007. California Office of Statewide Health Planning and Development. Available at: http://purl.stanford.edu/qn014cr7123. The 2007 (developed during July 2009 - July 2010) version contains the following geographic corrections: 1) MSSA 1.1 and 1.2 IDs (and associated MSSA Names) were swapped. 2) MSSA 175.1 and 175.2 IDs (and associated MSSA Names) were swapped. 3) MSSA 247 and 248 MSSA Names were swapped. The 2007 (developed during July 2009 - July 2010) version contains the following field calculation updates: 1) an update of fields affected by demographic changes reported in the Claritas 2007 data, except Poverty (at the 100 and 200% levels) were updated with Claritas 2007 data. Poverty values were updated by holding the percent levels constant from 2000 and calculating the population numbers based on the total populations 2) Hispanic population and percentages were directly calculated from the Claritas 2007 data (the sum total of columns EX through FD ('Current Year Hispanic or Latino:...race) from table SELCAT01.xls). 3) Race fields were calculated from 'Current Year...' race figures that include Hispanics or Latinos. It was confirmed that the sum total from columns EJ through EP in SELCAT01.xls ('Current Year...' race figures that include Hispanics or Latinos) equals the total population count (column M, POP_C, 'Current Year Population'). This might not be a change from the 2005 methodology, but it is important to note. 4) In January of 2010, Race fields for population count and percent population were added to the template feature class and calculated from "Current Year Not Hispanic or Latino." race figures from the Claritas 2007 data. 5) In July of 2010, povery percentages were corrected with re-calculated numbers developed by OSHPD. Poverty percentages were updated from the re-calculated US Census 2000 data. The population in poverty numbers were calculated on the civilian (non-group quarter) populations. Also "2007" was removed from field names. California, like several other Western states, has a large total area, but relatively few counties. As a result, county-based statistical systems mask significant disparities in population density between the urban and rural portions of many counties, and mask disparities in the socioeconomic status of the population within metropolitan areas. In 1976, California enacted legislation requiring the development of a geographic framework for determining which parts of the state were rural and which were urban, and for determining which parts of counties and cities had adequate health care resources and which were "medically underserved". Thus, sub-city and sub-county geographic units called "medical service study areas [MSSAs]" were developed, using combinations of census-defined geographic units, established following General Rules promulgated by a statutory commission. After each subsequent census the MSSAs were revised. In the scheduled revisions that followed the 1990 census, community meetings of stakeholders (including county officials, and representatives of hospitals and community health centers) were held in larger metropolitan areas. The meetings were designed to develop consensus as how to draw the sub-city units so as to best display health care disparities. The importance of involving stakeholders was heightened in 1992 when the United States Department of Health and Human Services' Health and Resources Administration entered a formal agreement to recognize the state-determined MSSAs as "rational service areas" for federal recognition of "health professional shortage areas" and "medically underserved areas". After the 2000 census, two innovations transformed the process, and set the stage for GIS to emerge as a major factor in health care resource planning in California. First, the Office of Statewide Health Planning and Development [OSHPD], which organizes the community stakeholder meetings and provides the staff to administer the MSSAs, entered into an Enterprise GIS contract. Second, OSHPD authorized at least one community meeting to be held in each of the 58 counties, a significant number of which were wholly rural or frontier counties. For populous Los Angeles County, 11 community meetings were held. As a result, health resource data in California are collected and organized by 541 geographic units. The boundaries of these units were established by community healthcare experts, with the objective of maximizing their usefulness for needs assessment purposes. The most dramatic consequence was introducing a process by which all local stakeholders could see relevant socioeconomic and healthcare resource data simultaneously displayed in a GIS format. A two-person team, incorporating healthcare policy and GIS expertise, conducted the series of meetings, and supervised the development of the 2000-census configuration of the MSSAs. William H. Burnett, Senior Advisor Healthcare Workforce and Community Development Division California Office of Statewide Health Planning and Development MSSA Configuration Guidelines (General Rules): - Each MSSA is composed of one or more complete census tracts. - As a general rule, MSSAs are deemed to be "rational service areas [RSAs]" for purposes of designating health professional shortage areas [HPSAs], medically underserved areas [MUAs] or medically underserved populations [MUPs]. - MSSAs will not cross county lines. - To the extent practicable, all census-defined places within the MSSA are within 30 minutes travel time to the largest population center within the MSSA, except in those circumstances where meeting this criterion would require splitting a census tract. - To the extent practicable, areas that, standing alone, would meet both the definition of an MSSA and a Rural MSSA, should not be a part of an Urban MSSA. - Any Urban MSSA whose population exceeds 200,000 shall be divided into two or more Urban MSSA Subdivisions. - Urban MSSA Subdivisions should be within a population range of 75,000 to 125,000, but may not be smaller than five square miles in area. If removing any census tract on the perimeter of the Urban MSSA Subdivision would cause the area to fall below five square miles in area, then the population of the Urban MSSA may exceed 125,000. - To the extent practicable, Urban MSSA Subdivisions should reflect recognized community and neighborhood boundaries and take into account such demographic information as income level and ethnicity. - Rural Definitions: A rural MSSA is an MSSA adopted by the Commission, which has a population density of less than 250 persons per square mile, and which has no census defined place within the area with a population in excess of 50,000. Only the population that is located within the MSSA is counted in determining the population of the census defined place. A frontier MSSA is a rural MSSA adopted by the Commission which has a population density of less than 11 persons per square mile. Any MSSA which is not a rural or frontier MSSA is an urban MSSA. The State of California and the Office of Statewide Health Planning and Development make no representations or warranties regarding the accuracy of data or maps. The user will not seek to hold the State or the Department liable under any circumstances for any damages with respect to any claim by the user or any third party on account of or arising from the use of data or maps. The user will cite the Office of Statewide Health Planning and Development as the original source of the data, but will clearly denote cases where the original data have been updated, modified, or in any way altered from the original condition. There are no restrictions on distribution of the data by users. However, users are encouraged to refer others to the Office of Statewide Health Planning and Development to acquire the data, in case updated data become available. This layer is presented in the WGS84 coordinate system for web display purposes. Downloadable data are provided in native coordinate system or projection.