About Birth Origin Studies

Robert C. Bowman, M.D.

About 95% of the graduates of United States allopathic medical schools (US MD Grads) can be traced to birth origins in the United States (city, state) or another country (foreign born US MD Grad). Physicians can be compared to census data to generate ratios of admission or probability of admission. These can also be compared across the same origins to physician career and location choice involving underserved areas, family medicine, and primary care.

It is important to remember that the same individual physicians are linked across birth origin (a form of experiential place), medical school, career choice, and practice location. codings include types of birth origins, types of medical schools, types of career choices, and types of practice location.

Birth Origins, Admission Ratios, Career Choice, and Distribution

1970

1970

1994 – 2000

1994 - 2000

1987 - 1998 Medical School Graduates

Pop Density of Birth County (Pop/Sq Mile) or other Origin

Population

US Born Medical School Grads

US Born Grads per 100,000 per class year

All Rural Physicians

Under-served Rural & Urban

Office Primary Care

Family Practice General Practice

1 to 16

5,863,912

1937

4.72

24.8%

8.6%

39.3%

27.4%

16 to 32

7,719,603

2586

4.79

22.8%

9.1%

38.9%

25.3%

32 to 62

17,071,584

5389

4.51

20.5%

8.3%

37.6%

23.2%

62 to 125

18,948,981

7384

5.57

18.1%

7.6%

35.5%

21.1%

125 to 250

21,750,406

7806

5.13

14.0%

6.0%

32.3%

18.2%

250 to 500

24,533,878

10168

5.92

11.6%

5.5%

32.8%

17.7%

500 to 1000

22,386,252

11040

7.05

10.6%

5.8%

32.0%

16.2%

1000 to 2500

48,245,786

24324

7.20

8.5%

4.4%

31.1%

14.1%

2500 to 5000

15,185,926

7419

6.98

8.4%

4.3%

28.5%

12.9%

5000 to 10000

9,841,413

5170

7.50

6.5%

4.1%

29.4%

12.8%

10000 or above

11,608,158

13019

16.02

5.2%

3.5%

26.5%

9.1%

Only State Data

 

1422

 

12.3%

6.4%

37.2%

24.3%

Military Birth

 

1273

 

13.1%

6.2%

30.5%

16.2%

US Born Total

203,155,899

109707

6.96

11.0%

5.3%

31.6%

15.8%

Foreign Born

19,000,000 in 1995 28,000,000 in 2000

19037

14.31

 

5.5%

5.1%

29.7%

10.6%

Linear relationships for admission and for distribution are seen across population density categorizations of birth counties. The physicians from the birth counties with lower concentrations of income, population, and physicians are more likely to choose family medicine, primary care, rural, and underserved locations. The family medicine choice is crucial as it multiplies rural or underserved practice locations (above origin, training, and age at graduation influences) and provides an increasing proportion of primary care in the most needed health access locations.

Birth origin counties have also been coded by 1969 per capita income. Lower and middle income origins are more likely for the lowest density origins along with military base birth. As county sizes get larger, there are more variations as a wide range of income origins exist within counties. Even in rural counties, physicians are more likely to arise from higher income or professional parents. Even so, the birth origin influences are consistent as demonstrated above and in other research. Foreign origins are also associated with higher income origins in census studies and in studies of US medical students, especially the new immigrants that are able to apply to a US medical school.

Consistency is found using experiential place as a framework or taxonomy for probability of admission or distribution. Physicians with origins associated with concentration or combinations of concentration (income, people, physicians, professionals, social organization, higher education) have higher probability of admission and lower probability of health access. These effects remain when controlling for age, other origins, type of training, and career choice. Coding for concentrations has included birth counties with concentrations of physicians (medical school counties, top physician to population), income, and professionals (bachelors degrees, professional and managerial occupation) as well as people.

Distribution is complicated by the fact that fewer are admitted from humble origin counties. Those most likely to gain admission have origins in the most densely populated counties and are the least likely to distribute to primary care, rural, and underserved locations.

 

Birth county methods are strong in that 95% of US MD Grads can be matched to birth in a defined county, type of county, or foreign nation; however variations are involved.

The weakness of birth origins involves less consistent birth origins data in osteopathic graduates (70%) or international graduates (50%) although international graduates can be coded with relative consistency by the country location of their medical school.

Other weaknesses are seen when counties are larger and there are more variation. There are ways to address this such as higher income rural counties and lower income urban counties. The results are consistent for concentrations in these situations. Also the results are consistent for populations such as Asian or foreign born physicians that can be tracked by birth origins or by ratios of career choice. Asian populations have top concentrations of origins by income, people, and professionals. Asian Indian choice of rural careers and family medicine careers is lowest at less than 3% each.

In rural counties, the variations are small. In large urban counties, birth origins are more variable. Lower income origin physicians cannot be separated from higher status origin physicians and foreign born physicians exist only in an entirely separate category without known US location prior to medical school.

Birth origins are national data. State and regional comparisons can be made, but must be adjusted for local workforce in rural and socioeconomic dimensions. Birth origin to physician distribution relationships are impacted at the state and local level by higher poverty levels (especially divisions into rich and poor). States with higher poverty will have more physicians in underserved areas, using the current underserved category.

Birth origins, especially when nearly complete, are a nice control for the origin factors in a global overview for national workforce. Proxy variables can be created that represent origins involving income, geographic origin, and parents. There is every indication that direct data is available such as parent income, parent origin, and MCAT score of the physician, but such data is rarely used beyond individual schools. Even so the result are so consistent regarding concentrations that there is little doubt that higher parent income and higher MCAT score is related to higher probability of admission and lower probability of needed health access.  

Beyond Policy Declines: Other Influences Moving Primary Care Up or Down

Research is about consistent results that help explain areas such as health access. Birth county income or population density, birth in a city or county with a medical school, and comparisons of types of medical schools by training are readily available and provide consistent results.

Origins must be integrated with training, career choice, and policy as all impact most needed health access. Policy is by far the most important. This is why a number of interventions appear to work very well during optimal health access policy periods (1970s and 1990s) and why little appears to work nearly all other decades. Some interventions that actually do not work can appear to work with the right beginning and ending points with a start in a poor policy period and an ending point at the end of the 1970s or 1990s. Also without origins, ages, career choices, and training impacts (type of school) it is not possible to have a valid workforce study involving health access. This is why studies of family medicine departments, student interest groups, Title VII, individual school, and individual residency program outcomes are invalid. Even the author’s own national study of family medicine residency programs regarding their rural contributions is hampered by the lack of origins, medical school training, age at graduation, and residency director assessments of practice locations of graduates as rural rather than direct physician practice zip codes,

The nation has demonstrated the ability to address needed health access, but chooses not to do so leaving more and more without. In the 1970s the nation quadrupled primary care production. This was a massive improvement in most needed health access as the preferred expansion involved family physicians. Also the nation doubled annual medical student production during this optimal policy period as more and more were choosing family medicine and primary care. Growth of Medicare and Medicaid with rebuilding of health care the infrastructure, and support for physicians choosing basic health access also optimized distributions of health resources and physicians. Primary care and specialty care needs were both addressed.

The current expansion fails completely for primary care with active destruction of existing primary care due to policy.

Most of all to gain some understanding of the entire situation, there must be awareness. The major problem for the United States in health care as well as banking, economics, education, and other areas is that people in 4% of the land area that are immersed in the top concentrations. This experiential place has far too much influence on politics, leadership, the media, health care, higher education, education, and more. The defect mostly involves lack of awareness of the day to day situations facing people in 96% of the land area with 65% of the population, usually lower and middle income Americans. Perhaps one of the saddest situations is the elderly who must move away from the most costly top concentrations to become 70% of the people that are outside of concentrations of physicians, but they are also in most need of health care and are less and less mobile with increasing age.

Physicians found in super centers with 200 or more physicians were traced to birth origins and were found to be more and more likely to arise from top concentrations. Higher probability of admission and higher probability of an exclusive medical school help shape exclusive concentrations in super center locations.

Physicians traced from underserved practice locations in 2005 are more likely to arise from populations with lower concentrations of people or income or both. Higher probability of underserved location are also associated with lower probability of medical school admission.

Physicians traced from rural practice locations in 2005 are more likely to arise from populations with lower concentrations of people or income or both. Higher probability of rural location are also associated with lower probability of medical school admission.

Family physicians were tracked to birth origin county coded by population density. There was a constant rate of 1 family physician admitted per 100,000 1970 birth county population per class year. The constant rate of family practice is contrasted with increasing admission probability of those with more urban (and higher income) birth county origins. Those most likely to gain admission with higher probability of admission were least likely to be found in family medicine. Those most likely to be found in family medicine arose from origins with lowest probability of medical school admission. Rural physicians, underserved physicians, and family physicians are the only types of physicians with a constant rate of origin across all populations

Family Physicians - Origins and Practice Locations More Likely to be Outside of Top Concentrations - from the 65% left outside and serving the 65% outside with outcomes involving the Physician Distribution by Concentration Coding   see also video comparisons at Shorter presentation comparing 5 Specialty Types from origins to practice locations

Specialists of a more general nature such as general surgeons, urologists, and ob-gyn physicians are traced to their origins and linked to their PDC practice locations

Hospital support physicians are captured by birth origin county population density as well as practice locations. Super center location dominates with major center location prominent and few located outside of concentrations. More exclusive origins result in more exclusive career and location choices.

Internal Medicine and Pediatric physicians are captured by birth origin county population density as well as practice locations. As with subspecialists and hospital support physicians, super center location dominates with major center location prominent and few located outside of concentrations. More exclusive origins result in more exclusive career and location choices. Indeed IM and PD generalists are 70% found in top concentrations in 4% of the land area.

Subspecialists have the most exclusive origins, are more likely to arise from exclusive origins, and are most likely to be found in super center exclusive concentrations of physicians

www.basichealthaccess.org

www.physicianworkforcestudies.org

www.ruralmedicaleducation.org