Physician Workforce: Physician Supply Increased in Metropolitan and Nonmetropolitan Areas but Geographic Disparities Persisted
Published: 2003-10-31T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: Through a variety of programs, the federal government supports the training of physicians and encourages physicians to work in underserved areas or pursue primary care specialties. GAO was asked to provide information on the physician supply and the generalist and specialist mix of that supply in the United States and the changes in and geographic distribution of physician supply in metropolitan and nonmetropolitan areas. To address these objectives, GAO analyzed data on physician supply and geographic distribution from 1991 and 2001.
section_title: What GAO Found
paragraphs: The U.S. physician population increased 26 percent, which was twice the rate of total population growth, between 1991 and 2001. During this period the average number of physicians per 100,000 people increased from 214 to 239 and the mix of generalists and specialists in the national physician workforce remained about one-third generalists and two-thirds specialists. Growth in physician supply per 100,000 people between 1991 and 2001 was seen in historically high-supply metropolitan areas as well as low-supply statewide nonmetropolitan areas. Between 1991 and 2001, all statewide nonmetropolitan areas and 301 out of the 318 metropolitan areas gained physicians per 100,000 people. Of those 17 metropolitan areas that experienced declines in the number of physicians per 100,000 people, only 2 had fewer total physicians in 2001 than 1991. Overall, nonmetropolitan areas experienced higher proportional growth in physicians per 100,000 people than metropolitan areas, but the disparity in the supply of physicians per 100,000 people between nonmetropolitan and metropolitan areas persisted. Nonmetropolitan counties with a large town (10,000 to 49,999 residents) had the biggest increase in physicians per 100,000 people of all county categories but their supplies per 100,000 people were still less than large and small metropolitan counties' supplies in 1991 and 2001. In written comments on a draft of this report, the Health Resources and Services Administration agreed with GAO findings of persisting disparities between metropolitan and nonmetropolitan areas.

section_title: Letter
paragraphs: The federal government has had a long-standing interest in ensuring an  adequate supply of physicians to meet the health care needs of the U.S.  population. Several federal programs provide funding to train physicians and encourage physicians to work in underserved areas. Other programs  attempt to encourage physicians to train as general or primary care  practitioners rather than specialists.
In anticipation of the reauthorization of several programs administered by  the Health Resources and Services Administration (HRSA) that fund  physician education and encourage physicians to practice primary care in underserved areas, you asked us to provide information on the physician supply in the United States. We are providing information on (1) the  national physician supply, supply per 100,000 people, and the generalist  and specialist mix in 1991 and 2001 and (2) changes from 1991 to 2001 in  physician supply, supply per 100,000 people, and the geographic  distribution of that supply in metropolitan and statewide nonmetropolitan  areas.
To address these objectives, we analyzed physician supply data from 1991  and 2001 for the nation, 318 individual metropolitan areas, 48 statewide  nonmetropolitan areas, and county categories. To provide information on  the physician workforce and its generalist-specialist mix, we analyzed  data from the American Medical Association (AMA) Physician Masterfile  and the American Osteopathic Association (AOA) Physician Masterfile. We  used data from the Census Bureau for resident population estimates based  on the 2000 Census. We aggregated county-level information to  metropolitan and statewide nonmetropolitan areas. We used urban  influence codes, a county categorization system developed by researchers  with the Economic Research Service in the Department of Agriculture, to  categorize metropolitan counties according to the size of the metropolitan  area and nonmetropolitan counties according to the size of the county’s  largest city and proximity to metropolitan areas. We also reviewed  relevant literature and interviewed experts on the U.S. physician  workforce. For more information on our scope and methodology see  appendix I. We performed our work from April through October 2003 in  accordance with generally accepted government auditing standards.
subsections: section_title: Background
paragraphs: From the 1950s until the early 1970s, concerns about physician shortages  prompted measures by the federal and state governments to increase  physician supply. Federal and state governments supported the growth in  the physician population by providing funds for constructing medical  schools and increasing medical school class sizes, offering loans and  scholarships to medical students, and paying hospitals through Medicare  to subsidize residency training costs. Concurrent with these initiatives, the  total physician supply and per-capita supply increased in the United  States.
By the 1980s and through the 1990s, however, concerns were raised about  the adequacy of the physician supply. A 1981 study by the Graduate  Medical Education National Advisory Committee (GMENAC) and a series  of reports from 1992 to 1999 by the Council on Graduate Medical  Education (COGME) forecast a national physician surplus. COGME  based these estimates on its determination that the appropriate target for  physician supply ranged from 145 to 185 physicians per 100,000 people.  These estimates were predicated in part on the belief that managed care,  with its emphasis on preventive care and reliance on primary care  gatekeepers exercising tight control over access to specialists, would  become a more typical health care delivery model. COGME and others  have noted that managed care has not become as dominant as predicted.  By 2000, some research concluded that physician supply increased even  more than these studies predicted. Some researchers, however,  questioned whether there was a national surplus of physicians.
A report from the Institute of Medicine (IOM) describes why studies of the  physician workforce vary. According to the IOM report, disagreement  about the adequacy of physician supply arises because there is no single  accepted approach to estimating physician supply or demand. Varying  assumptions related to factors that may affect future supply or demand  can lead to different conclusions about the adequacy of future physician  supply. Projecting future physician supply depends on the approach used  to count physicians, measure their productivity, and estimate the rate of  entrance into and exit from the profession. Estimating demand for  physicians’ services requires even more assumptions. Demand for  physicians’ services can be estimated using current and projected service  utilization patterns or by determining an ideal level of care to treat the  projected incidence and prevalence of illness among the population. In  addition, physician practice patterns, the use of new technology, the  supply and role of nonphysician providers, and rates and levels of  insurance coverage also affect estimates of the demand for and supply of  physicians’ services.
In spite of the difficulty of determining whether the overall number of  physicians is indeed the right number, there is little disagreement that  physicians have been located disproportionately in metropolitan areas  relative to the U.S. population. Geographic disparities in physician supply  have persisted even as the national physician supply has increased  steadily. Economic factors and professional preferences have all been  offered as evidence to explain why physicians, and specialists in  particular, locate in metropolitan areas. For example, physicians depend  on the availability of hospitals, laboratories, and other technology, and  metropolitan areas tend to have more of these facilities and equipment  than nonmetropolitan areas. Small nonmetropolitan areas generally lack a  large enough population or hospital resources to support a specialty  practice, because specialists handle less prevalent but more complicated  illnesses and require more specialized support facilities and technology.
To influence overall physician supply and address perceived physician  shortages in certain areas, several federal programs fund efforts to address  these issues. The bulk of federal dollars to support physician education is  through Medicare’s graduate medical education (GME) payments to  teaching hospitals, which totaled an estimated $7.8 billion in 2000, the  latest year for which data were available. These GME payments are  distributed based on the number of physicians being trained and  Medicare’s share of patient days in the hospital. Medicare also pays  physicians a 10 percent bonus above the usual payment amount for  services they provide to beneficiaries in health professional shortage areas  (HPSAs). These Medicare Incentive Payments totaled $104 million in  2002.
Programs intended to encourage health professionals to practice in  underserved areas and to support the training and education of health  professionals are administered by HRSA, within the Department of Health  and Human Services (HHS). HRSA programs include the National Health  Service Corps (NHSC) and grant and loan support programs for health  professions education and training. Most of these programs address three  objectives of improving the distribution of health professionals in  underserved areas, increasing representation of minorities and individuals  from disadvantaged backgrounds in health professions, and increasing the  supply of health professionals. They also address other objectives such as  improving the quality of education and training. In fiscal year 2001,  spending for the NHSC was $70.8 million and spending for health  professions education and training programs was $266 million. Funds for  the NHSC and for health professions education and training programs  support a range of health professions including medicine. See appendix II  for more information about program spending or appropriations and  program objectives.
section_title: National Physician Supply Grew at Twice the Rate of the U.S. Population
paragraphs: The number of physicians in the United States increased about 26 percent,  from about 541,000 to about 681,000 from 1991 to 2001. Physician growth  was twice that of national population growth during this period. As a  result, the total number of physicians per 100,000 people in the United  States climbed 12 percent, from 214 in 1991 to 239 in 2001. The number of  generalists per 100,000 people increased at about the same rate as the  number of specialists per 100,000 people. (See table 1.) The national  physician workforce maintained approximately a one-third generalist to  two-thirds specialist composition between 1991 and 2001.
Growth in physician supply reduced the number of metropolitan and  nonmetropolitan areas with fewer than 100 physicians per 100,000 people  and increased the number of areas with greater than 300 physicians per  100,000 people. In 1991, 8 metropolitan areas and 27 statewide  nonmetropolitan areas had fewer than 100 physicians per 100,000 people.  By 2001, no metropolitan areas and 7 statewide nonmetropolitan areas had  fewer than 100 physicians per 100,000 people. Twice as many metropolitan  areas and statewide nonmetropolitan areas had at least 300 physicians per  100,000 people in 2001 as in 1991. (See figs. 1 and 2.) In 1991, the 25  percent of areas with the lowest physician supplies per 100,000 people had  an average of 106 physicians per 100,000 people. By 2001, the 25 percent of  areas with the lowest physician supplies per 100,000 people had an  average of 132 physicians per 100,000 people. Similarly, the 25 percent of  areas with the highest physician supplies per 100,000 people had an  average of 319 physicians in 1991 and 362 physicians in 2001. See appendix  III for information on physician supply by state metropolitan and  nonmetropolitan areas in 1991 and 2001.
section_title: Physician Supply Per 100,000 People Increased in Most Areas but Geographic Disparities Persisted
paragraphs: All 48 statewide nonmetropolitan areas experienced an increase in the  number of physicians per 100,000 people from 1991 to 2001 and 301 of 318  metropolitan areas experienced an increase in physicians per 100,000  people. Overall, the nonmetropolitan areas had higher proportional growth  in physicians per 100,000 people than the metropolitan areas, but the  disparity in the supply of physicians per 100,000 people between the  metropolitan and nonmetropolitan areas persisted. Rates of growth in the  number of physicians per 100,000 people, the supply of physicians per  100,000 people, and the mix of generalists and specialists among  categories of metropolitan and nonmetropolitan counties varied. Among  the five county categories we analyzed, nonmetropolitan counties with a  large town had the biggest increase in physicians per 100,000 people from  1991 to 2001 and more physicians per 100,000 people than either  nonmetropolitan counties without a large town or rural counties, but still  fewer than metropolitan counties. Like metropolitan counties,  nonmetropolitan counties with large towns had more specialists than  generalists, while other nonmetropolitan counties had more generalists  than specialists.
subsections: section_title: Almost All Areas Gained Physicians Per 100,000 People
paragraphs: The 48 statewide nonmetropolitan areas, including those with the lowest  supplies of physicians per 100,000 people in 1991, registered gains in  physicians per 100,000 people between 1991 and 2001. However, this  growth rate was not even across all statewide nonmetropolitan areas and 7  areas remained below 100 physicians per 100,000 people. Five of these 7  statewide nonmetropolitan areas—Iowa, Indiana, Louisiana, Oklahoma,  and Texas—that remained below 100 physicians per 100,000 people, had  average increases in physicians per 100,000 people that were less than the  23 percent average increase for the nonmetropolitan United States. The  remaining 2—statewide nonmetropolitan Alabama and Tennessee—had  increases in physicians per 100,000 people that exceeded the national  nonmetropolitan area average, but the number of physicians in these areas  was so low in 1991 that this growth was not enough to elevate their  physician supply above 100 per 100,000 people in 2001.
In the aggregate, the 318 metropolitan areas of the United States  experienced an increase in physicians per 100,000 people between 1991  and 2001. However, 17 (5 percent) metropolitan areas experienced  declines in the number of physicians per 100,000 people during this period.  (See table 2.) In 2001, 11 of these areas had physician supplies per 100,000  people that were below the national average of 239 physicians per 100,000  people. Only 2 individual metropolitan areas, however—the Topeka,  Kansas and Enid, Oklahoma MSAs—experienced an actual decrease in  their physician populations between 1991 and 2001. While the remaining  15 areas had more physicians in 2001 than in 1991, the population increase  for all of them was large enough that they still experienced a decline over  that decade in the number of physicians per 100,000 people. Five of these  areas had physician population growth in excess of the national average of  26 percent. However, in these areas the higher-than-average growth in  physician supply was exceeded by population growth that was also above  the national average of 13 percent, resulting in a decline in physicians per  100,000 people.
section_title: Statewide Nonmetropolitan Areas Had Greater Proportional
paragraphs: The number of physicians per 100,000 people in nonmetropolitan areas, in  which 19 percent of the U.S. population resided in 2001, increased 23  percent from 1991 to 2001. During this same time, the number of  physicians per 100,000 people in metropolitan areas, in which 81 percent Increases in Physicians Per  of the U.S. population resided in 2001, increased 10 percent. (See table 3.)
The higher growth rate in physicians per 100,000 people in nonmetropolitan areas over the decade did not translate into a reduction  in the gap in the supply of physicians per 100,000 people in metropolitan  versus nonmetropolitan areas. The disparity in the supply of physicians  per 100,000 people between nonmetropolitan and metropolitan areas  persisted because physicians continued to disproportionately locate in  metropolitan areas. On net, about 17,000 physicians (12 percent of the  physician population increase) went to nonmetropolitan areas between  1991 and 2001, while about 123,000 (88 percent of the physician population  increase) went to metropolitan areas. The difference in physician supply  between metropolitan and nonmetropolitan areas remained relatively  unchanged from 1991, when the difference in supply was 143 per 100,000  people, to 2001 when the difference was 145 per 100,000 people.
In nonmetropolitan areas, the number of specialists per 100,000 people  increased faster than the number of generalists per 100,000 people. As a  result, the generalist and specialist composition shifted from an even mix  of generalists and specialists in 1991 to 48 percent generalists and 52  percent specialists in 2001. In metropolitan areas, generalists and  specialists per 100,000 people increased at approximately the same rate,  shifting the composition less than 1 percent from 36 percent generalists  and 64 percent specialists in 1991 to 35 percent generalists and 65 percent  specialists in 2001.
section_title: Rates of Growth in Physician Supply Differed Among Categories of Nonmetropolitan and Metropolitan Counties
paragraphs: To obtain additional information about physician supply within  nonmetropolitan and metropolitan areas, we aggregated county physician  and population data into five categories defined by a county’s  nonmetropolitan or metropolitan status and the presence and size of a  town within the county. All five county categories had an increase in  physicians per 100,000 people from 1991 to 2001. (See fig. 3.) But the rates  of growth in physician supply per 100,000 people, supply of physicians per  100,000 people, and mix of generalists and specialists varied by county  category. While nonmetropolitan counties with a large town (10,000 to  49,999 residents) had the biggest percentage increase in physicians per  100,000 people of all county categories, their supplies per 100,000 people  were still less than large and small metropolitan counties’ supplies in 1991  and 2001. Among nonmetropolitan counties, however, those with a large  town had more physicians per 100,000 people than those without a large  town or rural counties in 1991 and 2001. Like metropolitan counties,  nonmetropolitan counties that are more urbanized—those with a large  town—had more specialists than generalists per 100,000 people. Less  urbanized nonmetropolitan counties—those without a large town—and  rural counties had more generalists than specialists per 100,000 people in  1991 and 2001.
section_title: Agency Comments
paragraphs: We provided a draft of this report to HRSA for comment. HRSA said that  the study supports the conclusion that the disparity in the distribution of  physicians in rural and urban areas persists and has narrowed. HRSA also  agreed with our assessment of the difficulties and variation associated  with determining an appropriate supply for any given geographic area.  However, HRSA noted that the report should draw conclusions to make  the report more complete.
HRSA also commented that rural citizens are still grossly underserved,  noting that physician supply can be a rough measure of access to  physician services in a given area and that even in areas with a large  number of physicians many people still lack access due to a number of  factors. HRSA’s comments are reprinted in appendix IV.
Although we found that a geographic disparity persists, we did not find  that the disparity in the distribution between metropolitan and  nonmetropolitan areas has narrowed. Physician supply grew faster in  nonmetropolitan than metropolitan areas, on a national basis, but this did  not reduce the disparity because there are so many physicians in  metropolitan areas. As we stated in the draft report that HRSA reviewed,  while nonmetropolitan areas experienced higher growth rates in  physicians per 100,000 people, the difference in physician supply per  100,000 people remained relatively unchanged from 1991 to 2001.
HRSA noted that physician supply is only one of several factors affecting  the accessibility of health care in an area. However, assessing the  adequacy of access to physicians was beyond the scope of our work.  HRSA also provided technical comments that we incorporated as  appropriate.
We are sending copies of this report to the Administrator of the Health  Resources Services Administration and other interested parties. We will  also provide copies to others upon request. In addition, the report will be  available at no charge on the GAO Web site at http://www.gao.gov. If you  or your staff have any questions about this report, please call me at (202)  512-7119 or Christine Brudevold at (202) 512-2669. Major contributors to  this report were Kathryn Linehan and Ann Tynan.
section_title: Appendix I: Scope and Methodology
paragraphs: To conduct this work, we counted active, nonfederal, patient care  physicians with a known address, including interns and residents, in the  United States. We used individual physician-level data on medical doctors  (MD) from the 1991 and 2001 American Medical Association (AMA)  Physicians’ Professional Data, also known as the AMA Masterfile and 1991  and 2001 data on doctors of osteopathic medicine (DO) from the American  Osteopathic Association (AOA) Masterfile. These data are widely used in  studies of physician supply because they are a comprehensive list of U.S.  physicians and their characteristics.
To determine physician supply per 100,000 people, we obtained county- level resident population data for 1991 and 2001 from the U.S. Census  Bureau Web site. We used data from the Department of Agriculture Web  site to determine urban influence codes for each county. For additional  information about physician supply in the United States, we reviewed  relevant literature and interviewed academic researchers on the topic of  the U.S. physician workforce.
To obtain federal program information, we interviewed officials from the  Health Resources and Services Administrative (HRSA) and officials at the  Centers for Medicare & Medicaid Services (CMS). HRSA officials provided  information on the scope and expenditures of health professions training  and education programs and the National Health Service Corps. CMS  officials provided information on the Medicare Incentive Payments to  physicians providing services in health professional shortage areas.
We combined counts of MDs and DOs to determine the total number of  physicians in each of our study years. Each physician was counted without  adjustment for hours worked. To determine physicians per 100,000 people,  we divided the physician population in a given area by the total population  in the area in that same year. To count generalists and specialists we used  each physician’s specialty information in the AMA and AOA data files to  categorize physicians as generalists or specialists. Physicians whose  specialty information was listed as family practice, general practice,  general internal medicine, and general pediatrics were categorized as  generalists. All other physicians with specialty information available were  categorized as specialists.
To assign physicians to a geographic area in the United States, we used  address information in the AMA and AOA data files. The address  information in these files does not specify whether the address refers to  the physician’s home, office, or some other location and it is possible that  some physicians live and work in different counties. Because of this  limitation, we did not analyze the data at the individual county level. We  combined multiple, adjacent counties into larger geographic units. We  assigned counties to a metropolitan statistical area (MSA), primary  metropolitan statistical areas (PMSA), or New England county  metropolitan area (NECMA). We grouped data from all areas within a state  that were not in a MSA, PMSA, or NECMA into one statewide  nonmetropolitan area for each state. We used 2001 MSA, PMSA, and  NECMA classifications for the 2001 and 1991 data.
For analysis by county categories, we used urban influence codes, which  group metropolitan and nonmetropolitan counties according to the official  metropolitan status announced by the Office of Management and Budget  in 1993, based on 1990 Census data. Urban influence codes group counties,  county equivalents, and independent cities into nine categories.Metropolitan counties are grouped into two categories (1 and 2) by the  size of the metropolitan area. Nonmetropolitan counties are grouped into  seven groups (3 through 9) by their adjacency to metropolitan areas and  the size of their own city. For this analysis of physician supply, we  maintained categories 1, 2, and 9 and collapsed the remaining six  categories into two, for a total of five categories. This analysis combines  codes 3, 5, and 7 into one category (i.e., nonmetropolitan with a large  town) and 4, 6, and 8 into one category (i.e., nonmetropolitan without a  large town).
section_title: Appendix II: HRSA Programs That Address Supply and Distribution of Health Professionals
paragraphs: HRSA administers programs that encourage health professionals to  practice in underserved areas and support health professions education  and training. The National Health Service Corps and the State Loan  Repayment Program, authorized by Title III of the Public Health Service  Act, offer scholarships and loan repayments to health professionals in  exchange for a commitment to practice in health professional shortage  areas. Grant and loan support programs that support health professions  education and training, authorized by Title VII of the Public Health Service  Act, have diverse objectives. Generally, these programs support education  and training for a range of health professions including medicine,  chiropractics, dentistry, optometry, pharmacy, physician assistants, allied  health, and public health. While most of the Title VII programs address  three objectives of improving the distribution of health professionals in  underserved areas, increasing representation of minorities and individuals  from disadvantaged backgrounds in health professions, and increasing the  supply of health professionals, they also address other objectives such as  improving the quality of education and training. Table 4 provides  information on Title III and Title VII program spending or appropriations  and objectives.
section_title: Appendix III: Physicians Per 100,000 People by State Metropolitan and Nonmetropolitan Areas, 1991 and 2001
section_title: Related GAO Products
paragraphs: Health Workforce: Ensuring Adequate Supply and Distribution Remains  Challenging. GAO-01-1042T. Washington, D.C.: August 1, 2001.
Nursing Workforce: Emerging Nurse Shortages Due to Multiple Factors.  GAO-01-944. Washington, D.C.: July 10, 2001.
Nursing Workforce: Multiple Factors Create Nurse Recruitment and  Retention Problems. GAO-01-912T. Washington, D.C.: June 27, 2001.
Nursing Workforce: Recruitment and Retention of Nurses and Nurse  Aides Is a Growing Concern. GAO-01-750T. Washington, D.C.: May 17,  2001.
Health Care Access: Programs for Underserved Populations Could Be  Improved. GAO/T-HEHS-00-81. Washington, D.C.: March 23, 2000.
Community Health Centers: Adapting to Changing Health Care  Environment Key to Continued Success. GAO/HEHS-00-39, Washington,  D.C.: March 10, 2000.
Physician Shortage Areas: Medicare Incentive Payments Not an  Effective Approach to Improve Access. GAO/HEHS-99-36. Washington,  D.C.: February 26, 1999.
Health Care Access: Opportunities to Target Programs and Improve  Accountability. GAO/T-HEHS-97-204. Washington, D.C.: September 11,  1997.
Foreign Physicians: Exchange Visitor Program Becoming Major Route  to Practicing in U.S. Underserved Areas. GAO/HEHS-97-26. Washington,  D.C.: December 30, 1996.
National Health Service Corps: Opportunities to Stretch Scarce Dollars  and Improve Provider Placement. GAO/HEHS-96-28. Washington, D.C.:  November 24, 1995.
Health Care Shortage Areas: Designations Not a Useful Tool for  Directing Resources to the Underserved. GAO/HEHS-95-200. Washington,  D.C.: September 8, 1995.
Health Professions Education: Role of Title VII/VIII Programs in  Improving Access to Care is Unclear. GAO/HEHS-94-164. Washington,  D.C.: July 8, 1994.