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Table A1: Safety Net Measures in this Data Book, their Definitions, and Data Sources (continued)
Health Care Delivery System
Measure 
Definition 
Data Source(s) 
Methodological Notes 
HMO Competition Index 
HMO competition index 
An index that indicates the extent to which the market share of managed care is concentrated in a small number of health plans, with a higher value indicating greater concentration. ("Herfindahl Index") 
1999 InterStudy 
Data available at the MSA level only. 
HMO Penetration % 
HMO penetration rate 
Percent of area population enrolled in Health Maintenance Organizations. 
1999 InterStudy 
Data available at the MSA level only. 
Medicare Managed Care Penetration (%) 
Medicare managed care penetration 
Number of Medicare managed care enrollees divided by the total number of Medicare beneficiaries. 
2001 Area Resource File
(1999 Data) 

Physician Supply per 100, 000 
Number of pediatricians per 100,000 children 
Number of pediatricians divided by the number of individuals ages 017, multiplied by 100,000 (nonFederal, patient care physicians). 
Numerator from 2001 Area Resource File (1999 Data); Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Number of adult primary care providers per 100,000 adults 
Number of general internists, family practitioners, and general practitioners, divided by the number of individuals age 18 and older, multiplied by 100,000 (nonFederal, patient care physicians). 
Numerator from 2001 Area Resource File (1999 Data); Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Number of obstetricians/gynecologists per 100,000 women 
Number of obstetricians/gynecologists divided by the total number of women age 15 and older, multiplied by 100,000 (non Federal, patient care physicians). 
Numerator from 2001 Area Resource File (1999 Data); Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Number of medical specialty doctors per 100,000 population 
Number of medical specialty doctors divided by the total population, multiplied by 100,000 (nonFederal, patient care physicians). Medical specialties include allergy and immunology, cardiovascular disease, dermatology, gastroenterology, internal medicine subspecialties, pediatric subspecialties, pediatric cardiology, and pulmonary disease. 
Numerator from 2001 Area Resource File (1999 Data); Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Number of surgical specialty doctors per 100,000 population 
Number of surgical specialty doctors, divided by the total population, multiplied by 100,000 (non Federal, patient care physicians). Surgical specialties include colon/ rectal surgery, general surgery, neurological surgery, ophthalmology, orthopedic surgery, otolaryngology, plastic surgery, thoracic surgery, and urology. 
Numerator from 2001 Area Resource File (1999 Data); Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Supply/Utilization per 1,000 
Number of inpatient hospital beds per 1,000 population 
Number of inpatient hospital beds divided by the total population, multiplied by 1,000 (nonFederal general medical/surgical facilities). 
Numerator from 1999 American Hospital Association Annual Survey; Denominator from 2001 Claritas (1999 interpolated estimate) 

Number of inpatient hospital admissions per 1,000 population 
Number of admissions to inpatient hospitals divided by the total population, multiplied by 1,000 (nonFederal general medical/surgical facilities). 
Numerator from 1999 American Hospital Association Annual Survey; Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
Number of emergency department visits per 1,000 population 
Number of visits to emergency departments divided by the total population, multiplied by 1,000 (nonFederal general medical/surgical facilities). 
Numerator from 1999 American Hospital Association Annual Survey; Denominator from 2001 Claritas (1999 interpolated estimate) 
Figures are based on location of physician (not patient origin which may be from other counties). 
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Community Context—Population
Measure 
Definition 
Data Source(s) 
Total Population 
Total population 
Total number of people in the area. 
U.S. Census 2000 
Square Miles 
Square miles 
The size of the area in square miles. 
2001 Claritas (1999 interpolated estimate) 
Population Density 
Population density 
Total population, divided by the number of square miles. 
Numerator from U.S. Census 2000; Denominator from 2001 Claritas (1999 interpolated estimate) 
% Population 
Percent of population ages 017 
Population ages 017 divided by the total population. 
U.S. Census 2000 
Percent of population ages 1864 
Population ages 1864 divided by the total population. 
U.S. Census 2000 
Percent of population age 65 and older 
Population age 65 and older divided by the total population. 
U.S. Census 2000 
% Population Change 19902000 
Percent population change 19902000, total 
2000 total population minus 1990 total population, divided by 1990 population. 
U.S. Census 2000 
Percent population change 19902000, ages 017 
2000 total population ages 017 minus 1990 total population ages 017, divided by 1990 population aged 017. 
U.S. Census 2000 
Percent population change 19902000, ages 1864 
2000 total population ages 1864 minus 1990 total population ages 1864, divided by 1990 population ages 1864. 
U.S. Census 2000 
Percent population change 19902000, age 65 and older 
2000 total population age 65 and older minus 1990 total population age 65 and older, divided by 1990 population age 65 and older. 
U.S. Census 2000 
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Community Context—Race/Ethnicity
Measure 
Definition 
Data Source(s) 
Methodological Notes 
% Population 
Percent of the population identifying their race as white 
Number of individuals reporting white race divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying their race as black 
Number of individuals reporting black race divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying their race as Asian American 
Number of individuals reporting AsianAmerican race divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying their race as Native American 
Number of individuals reporting NativeAmerican race divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying their race as Native Hawaiian or Pacific Islander 
Number of individuals reporting Native Hawaiian and other Pacific Islander race, divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying their race as "other" 
Number of individuals reporting some other race (not white, black, Asian American, Native American, or Pacific Islander), divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
Percent of the population identifying two or more races 
Number of individuals indicating two or more races divided by the total population reporting race. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for race. 
% Population Hispanic (Any Race) 
Percent of the population identifying their ethnicity as Hispanic or Latino, any race 
Number of individuals reporting Hispanic ethnicity divided by the total population reporting ethnicity. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for Hispanic categories. 
Percent of the population identifying their ethnicity as Mexican, any race 
Number of individuals reporting Mexican ethnicity divided by the total population reporting ethnicity. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for Hispanic categories. 
Percent of the population identifying their ethnicity as Puerto Rican, any race 
Number of individuals reporting Puerto Rican ethnicity divided by the total population reporting ethnicity. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for Hispanic categories. 
Percent of the population identifying their ethnicity as Cuban, any race 
Number of individuals reporting Cuban ethnicity divided by the total population reporting ethnicity. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for Hispanic categories. 
Percent of the population identifying their ethnicity as other Hispanic or Latino, any race 
Number of individuals reporting "Other Hispanic or Latino" ethnicity (not Mexican, Puerto Rican, or Cuban) divided by the total population reporting ethnicity. 
U.S. Census 2000 
See U.S. Census 2000 documentation for detailed description of definitions for Hispanic categories. 
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Community Context— Indices of Racial and Economic Separation
Measure 
Definition 
Data Source(s) 
Racial Dissimilarity Indices 
Racial dissimilarity index–Black 
Percent of the black population in an area that would have to move for all area zip codes to have an equal proportion of the area's black population. 
2001 Claritas (1999 interpolated estimate) 
Racial dissimilarity index–Hispanic 
Percent of the HispanicAmerican population in an area that would have to move for all area zip codes to have an equal proportion of the area's Hispanic population. 
2001 Claritas (1999 interpolated estimate) 
Racial dissimilarity index–All nonwhite 
Percent of the nonwhite population in an area that would have to move for all area zip codes to have an equal proportion of the area's nonwhite population. 
2001 Claritas (1999 interpolated estimate) 
Economic Indices 
Gini coefficient 
The proportion of income that would have to be redistributed to equalize the incomes of all residents of an area. 
2001 Claritas (1999 interpolated estimate) 
Economic dissimilarity index 
Percent of the population with family incomes less than $15,000 per year in an area that would have to move for all area zip codes to have an equal proportion of the population with family incomes less than $15,000 per year. 
2001 Claritas (1999 interpolated estimate) 
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Community Context— Immigrant Population
Measure 
Definition 
Data Source(s) 
% Population Foreign Born 
Percent of the population that is foreign born 
Number of individuals born outside of the U.S. divided by the total population for whom nativity and place of birth is reported. 
U.S. Census 2000 
Foreign Born 
Percent of the foreignborn population that has lived in the U.S. 10 years or less 
Number of individuals born outside of the U.S. who have lived in the U.S. for 10 years or less, divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Percent of the foreignborn population that has been naturalized as a U.S. citizen 
Number of individuals born outside of the U.S. who have been naturalized as U.S. citizens, divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of Foreign Birth 
Place of foreign birth: Latin America 
Number of individuals born in Latin America divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of foreign birth: Asia 
Number of individuals born in Asia divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of foreign birth: Africa 
Number of individuals born in Africa divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of foreign birth: Europe 
Number of individuals born in Europe divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of foreign birth: North America 
Number of individuals born in North America (outside of the U.S.), divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
Place of foreign birth: Oceania 
Number of individuals born outside of the U.S. but not on one of the abovenamed continents (Latin America, Asia, Africa, Europe, or North America), divided by the total number of individuals born outside of the U.S. 
U.S. Census 2000 
% Speak NonEnglish at Home 
Percent of the population speaking a language other than English at home 
Number of individuals age 5 and older speaking a language other than English at home, divided by the total population age 5 and older who reported language spoken at home. 
U.S. Census 2000 
% Speak English Less Than Very Well 
Percent of the population speaking English less than very well 
Number of individuals age 5 and older who report speaking English less than very well, divided by the total population age 5 and older who reported language spoken at home. 
U.S. Census 2000 
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