metropolitan and nonmetropolitan settings

The national distribution of Certified Registered Nurse Anesthetists across metropolitan and nonmetropolitan settings MICHAEL D. FALLACARO, CRNA, DNS THOMAS E. OBST, CRNA, MS Buffalo, New York IRA P. GUNN, CRNA, MLN, FAAN El Paso, Texas MANQUING CHU, BA Buffalo, New York The purpose of this study is to describe the metropolitan and nonmetropolitan distribution of Certified Registered Nurse Anesthetists actively practicing across the United States. More than 3,000 counties of the United States were categorized according to of urbanization by utilizing the rural-urban continuum codes for metropolitan and nonmetropolitan counties developed within the U.S. Department of Agriculture. Zip code information was used to locate all actively practicing CRNAs by county of residence. Applying the rural-urban continuum codes to this database revealed a descriptive national distribution of CRNAs across geographical areas. Data show that 81.3% (18,086) of CRNAs reside in metropolitan counties and that 18.7% (4,182) reside in nonmetropolitan areas. The greatest number of CRNAs (8,519) are found in central counties of metropolitan areas of one million population or more. The lowest number of CRNAs (90) are found in completely rural counties of fewer than 2,500 urban population adjacent to a metropolitan area, and 160 CRNAs reside in counties of fewer than 2,500 population not adjacent to a metropolitan area. Differences in age, gender distribution, educational credentials, and population ratios are also noted between metropolitan and nonmetropolitan CRNAs. Key words: Anesthesia manpower, metropolitan area, rural-urban continuum. Introduction While it appears that the generic nursing shortage has subsided across the United States," 2 regional maldistributions of nurses have affected select geographical regions with the smallest rural facilities still experiencing some shortages.; Certified Registered Nurse Anesthetists (CRNAs) are well known providers of anesthesia care in rural America. However, accurate and complete data on total anesthesia manpower in rural healthcare settings are not readily available. Estimates of the fraction of patients in rural America served by CRNAs have varied from 65% to 85%. 4. These numbers are debated in light of both conceptual and methodological concerns. The lack of any standardized conceptualization of "rural" has been purported to be one cause of some confusion in this area. Investigators have employed multiple definitions of rural/urban terminology to range from raw population data to population density calculations." A recent study of anesthesia in underserved, small, and rural hospitals was conducted by the June 1996/ Vol. 64/No. 3 237

Education and Research Department at the American Association of Nurse Anesthetists (AANA). This study analyzed data from two surveys of hospitals, one by the American Hospital Association and one by the SMG Marketing Group. The executive summary indicates that of the 9,722 CRNAs reported by hospitals as working in their setting during the year, about 80% were in urban as compared to rural hospitals and close to 80% were in large as opposed to small hospitals. When combining hospital types, just under 75% of CRNAs reported by hospitals worked in large, urban settings, and about an additional 13% worked in small, rural hospitals defined as being outside of a metropolitan area (MA). 5 The purpose of this study is to describe the metropolitan and nonmetropolitan distribution of CRNAs actively practicing in the United States. Additionally, this study examines the CRNA variables of age, gender, and highest educational level across geographical categorizations. Four research questions were proposed. 1. How are practicing CRNAs who reside in the United States distributed across the rural/ urban continuum? 2. What is the gender distribution of CRNAs residing in metropolitan and nonmetropolitan areas? 3. Does age vary between CRNAs residing in metropolitan and nonmetropolitan areas? 4. Do educational credentials differ between CRNAs residing in metropolitan and nonmetropolitan areas? Methods Our analyses are based upon county level data from two comprehensive databases. CRNA age, gender, highest educational level, and residence zip code information for all active certified and active recertified members of the AANA (22,268) was obtained from the AANA Membership and Information Systems Department. Utilizing FoxPro and ArcView for PC TM software, the zip code data was cross referenced to locate CRNA place of residence by county. The second database obtained from the U.S. Department of Agriculture, entitled "Rural-Urban Continuum Codes for Metro and Nonmetro Counties" was employed in this research. 7 This database forms a county classification scheme distinguishing metropolitan counties by population size and nonmetropolitan counties by of urbanization or proximity to metropolitan areas. This classification scheme was developed by taking the standard Bureau of the Census metropolitan and nonmetropolitan categories and subdividing them into a 10-part county codification with four metropolitan and six nonmetropolitan categories resulting. This scheme allows for a finer breakdown of metropolitan and nonmetropolitan data into specific residential groupings. Within the rural/urban continuum database, metropolitan counties are further distinguished by the population size of the metropolitan area (MA) of which they are a part. The U.S. Office of Management and Budget (OMB) defines MAs according to published standards that are applied to Census Bureau data. Three lists concern areas designated by the OMB as metropolitan statistical areas (MSAs), consolidated metropolitan statistical areas (CMSAs), and primary metropolitan statistical areas (PMSAs). The general concept of an MA is that of an area containing a large population core, together with adjacent communities having a high of economic and social assimilation with that core. Currently defined MAs are based upon the application of 1990 census data with estimates made through the year 1994. Standard definitions of metropolitan areas were first issued in 1949 by the then Bureau of the Budget under the designation "standard metropolitan area" (SMA). The term was changed to "standard metropolitan statistical area" (SMSA) in 1959, and to "metropolitan statistical area" in 1983. The current collective term "metropolitan area," became effective in 1990. The standards for defining metropolitan areas were modified in 1958, 1971, 1975, 1980, and 1990. The current OMB standards provide that each MSA must include at least one city with 50,000 or more inhabitants, or a Census Bureau-defined urbanized area (of at least 50,000 inhabitants) and a total metropolitan population of at least 100,000 (75,000 in New England). Under the standards, the county (or counties) that contains the largest city becomes the central county (counties), along with any adjacent counties that have at least 50% of their population in the urbanized area surrounding the largest city. An area that meets these requirements for recognition as an MSA and also has a population of one million or more may be recognized as a CMSA if separate component areas can be identified within the entire area by meeting statistical criteria specified in the standards, and local opinion indicates there is support for the component areas. 7 According to a July 1, 1994 Bureau of the Census estimate, 207,425,775 people reside in metropolitan areas and about 52,874,790 people reside in nonmetropolitan areas throughout the United States. In the United States, 3,140 counties were classified according to the rural-urban coding scheme. As described, these codes ranged from zero (0), 238 Journal of the American Association of Nurse Anesthetists

indicating central counties of metropolitan areas of one million population or more, to nine, indicating completely rural areas of fewer than 2,500 urban population which are not adjacent to a metropolitan area. Adjacency is determined by physical county boundary adjacency and finding that at least 2% of the employed labor force in the nonmetropolitan county commuted to metropolitan central counties. Broad categorizations of metropolitan and nonmetropolitan are designated. Metropolitan counties include rural-urban classification codes 0-3, and nonmetropolitan counties include classification codes 4-9 (Table 1 and Figure 1). Table I continuum codes Code Metropolitan counties 0 Central counties of MAs of 1 million population or more 1 Fringe counties of MAs of 1 million population or more 2 Counties in MAs of 250,000 to 1 million population 3 Counties in MAs of fewer than 250,000 population Code Nonmetropolitan counties 4 Urban population of 20,000 or more, adjacent to an MA 5 Urban population of 20,000 or more, not adjacent to an MA 6 Urban population of 2,500 to 19,999, adjacent to an MA 7 Urban population of 2,500 to 19,999, not adjacent to an MA 8 Completely rural or fewer than 2,500 urban population, adjacent to an MA 9 Completely rural or fewer than 2,500 urban population, not adjacent to an MA MA-Metropolitan area Note: Adjacency was determined by physical boundary adjacency and a finding that at least 2% of the employed labor force in the nonmetropolitan county commuted to metropolitan central counties. Applying the rural-urban continuum codes to the CRNA county of residence database revealed a descriptive national distribution of CRNAs across metropolitan and nonmetropolitan geographical areas. Findings Table II displays the distribution of CRNA subjects across the rural-urban categorical classifications. Data reveal that 81.3% (18,086) of CRNA subjects reside in metropolitan counties (ruralurban continuum codes of 0-3) and that 18.7% (4,182) reside in nonmetropolitan counties (ruralurban continuum codes 4-9). The greatest number of CRNAs (8,519), comprising 38.2% of the subjects are found in central counties of metropolitan areas of one million population or more. The least number of CRNAs (90), comprising 0.4% of the subjects are found in completely rural counties of fewer than 2,500 urban population adjacent to a metropolitan area, and 160 CRNAs (0.7%), reside in counties of fewer than 2,500 population. This table also describes the distribution of the more than 260,000,000 people residing in the United States by rural-urban continuum code classification and gives the CRNA to 100,000 population ratio in each of these categories. The highest ratio (11.91) is noted in counties in MAs of fewer than 250,000 population, and the lowest ratio (3.39) of CRNAs to 100,000 population is seen in completely rural counties or fewer than 2,500 urban population adjacent to an MA. (Table II). Table II CRNA distribution/population ratios by rural-urban code Rural- Total Percent Estimate Ratio urban number of total population CRNA/ code of CRNAs members July 1994 100,000 0 8,519 38.2 117,810,609 7.23 1 763 3.4 9,961,600 7.66 2 6,302 28.3 58,653,642 10.74 3 2,502 11.2 20,999,924 11.91 4 760 3.4 9,910,840 7.67 5 692 3.1 6,689,202 10.35 6 1,275 5.7 16,778,439 7.60 7 1,205 5.4 13,199,557 9.13 8 90.4 2,653,688 3.39 9 160.7 3,643,064 4.39 n = 22,268 Data describing CRNA gender distributions revealed that 62.9% (11,382) of the CRNAs in metropolitan areas were female and 37.1% (6,704) were males. This contrasted with findings that in nonmetropolitan areas 40.2% (1,682) of the CRNA subjects were female and 59.8% (2,500) were male (Table III). Table III also presents the distribution of CRNA mean age data by rural-urban county classification. The mean age of CRNAs residing in metropolitan and nonmetropolitan areas was found to be different with nonmetropolitan CRNAs being 2 years older than metropolitan CRNAs (n = 22,136). June 1996/ Vol. 64/No. 3 239

Figure 1 Rural urban continuum area Table III CRNA gender and age by area Area Metropolitan codes 0-3 Nonmetropolitan codes 4-9 Number of CRNAs 18,086 4,182 Percent of total members 81.3 18.7 Gender Female Male Age Mean in years 11,382 62.9 6,704 37.1 44.47 1,682 40.2 2,500 59.8 46.51 n = 22,268 Age: n = 22,136 When examining CRNA highest educational level, findings were remarkable in that a higher percentage of nonmetropolitan CRNAs as opposed to metropolitan CRNAs reported their highest educational level at the diploma and associate's level. Conversely, a greater percentage of metropolitan CRNAs reported their highest educational level at the master's and doctoral level (Table IV). CRNAs in both metropolitan and nonmetropolitan areas demonstrated similar percentages of bachelor's s at 38.3% and 38.8% respectively. Discussion These results serve to support the findings reported in the AANA study of underserved, small, 240 Journal of the American Association of Nurse Anesthetists

Table IV CRNA highest educational level by area Diploma Metropolitan 4,488 24.8 codes 0-3 Nonmetropolican 1,332 31.8 codes 4-9 n =21,352 Area Associate's Bachelor's 1,517 8.4 6,933 38.3 552 13.2 1,623 38.8 Master's 4,187 23.2 533 12.7 Doctoral 159.9 28.7 and rural hospitals, with the majority of CRNAs being found in metropolitan areas. 5 This finding is of no surprise given general population demographics and locations of healthcare facilities. In 1987, Grundy et al studied the characteristics of nurse anesthetists working with and without anesthesiologists. She found that those CRNAs working without an anesthesiologist practiced in predominantly small or rural communities, were more likely to be male and older, and less likely to hold a baccalaureate than those working with anesthesiologists in more urban areas. 8 This study supports these descriptive findings. A limitation of this study is the assumption that most CRNAs practice within their respective counties of residence. Further study employing a stratified sample of CRNAs across code categories is needed to validate this assumption. Overall, data indicate that there are 8.72 CRNAs per 100,000 population in metropolitan areas as opposed to 7.91 CRNAs per 100,000 population residing in nonmetropolitan areas within the United States. These findings suggest that the public's access to CRNA services across geographical designations may be similar. In an unpublished study conducted for the Texas Association of Nurse Anesthetists, Gunn and Dunlap reported that there were 8.46 CRNAs per 100,000 population in Texas as opposed to 10.04 anesthesiologists per 100,000 population. Also, of the 254 Texas counties, CRNAs were the sole anesthesia providers in approximately 81 counties serving more than 1.7 million people." National data on non-crna anesthesia providers by county of residence is needed to give a more thorough and representative picture of anesthesia delivery and access. In 1994, the ratio of anesthesiologists per 100,000 U.S. population was reported at 9.2. Sixteen states report to have between 6 to 8.9 anesthesiologists per 100,000 people with one state reporting 19 to 21.9 anesthesiologists per 100,000 population." It is known that despite a more than doubling in the national supply of anesthesiologists in the United States since 1980, the primarily urban geographic distribution of anesthesiologists has only changed slightly. As reported in 1995, hospitals with fewer than 200 beds and in communities of under 100,000 gained some anesthesiologists, but otherwise the distribution of anesthesiologists has not changed materially from 1980." Furthermore, it is noted that very substantial, unrealistic enhancements to surgical case loads would be needed in many instances to offset negative influences to rural locations to attract anesthesiologists. Even with the emerging glut of anesthesiologists, it is unlikely that the relatively low numbers of anesthesiologists in rural America will change significantly. 2, 13 Training an appropriate mix of physicians and various healthcare providers to meet the healthcare needs of people in various geographic 14, 15 settings are topics of much continued debate. Further study is needed to explain the noted difference in CRNA gender distributions seen across metropolitan and nonmetropolitan geographical settings. Sociological hypotheses related to gender roles in marriage and decisions regarding geographical family location based upon the primary wage earner may be useful in this area, and no inference is made from these findings at this time. Noted contrasts in CRNA academic credentials across settings may be related to age differences and the location of centers of higher learning in predominantly metropolitan areas. Additionally, older anesthetists may have received their education from institutions not offering graduate s at the time of their training. Age differences noted may prove valuable in predicting the CRNA workforce supply in a select geographical area based upon projected retirements. When looking at the distribution of the 3,530 CRNAs in the United States who are 55 years of age or older, 2,738 (71%) reside in metropolitan June 1996/ Vol. 64/No. 3 241

counties and 792 (29%) are found in nonmetropolitan counties. These percentages are at variance with the total CRNA population distribution where 81.3% reside in metropolitan and 18.7% in nonmetropolitan areas. Given this difference, one can anticipate a potential greater percentage loss of CRNAs from nonmetropolitan areas due to retirement over the next 10 years than in metropolitan areas. Trends in general nursing practice also reveal similar concerns about the steadily increasing mean age of registered nurses and the impact this may have on the projected overall nursing workforce for the 21st century.' 6 Summary This study describes the national rural/urban distribution of CRNAs by county of residence in the United States. This data will prove foundational to future research proposed to examine the practice patterns of nurse anesthetists in various geographical settings and may help identify any barriers to such practice. Additionally, future CRNA workforce and educational needs may be inferred from this study. Attention must also be paid to those factors influencing CRNA decisions to locate in nonmetropolitan as opposed to metropolitan areas. Many economic, demographic, and health-related disparities exist between rural and urban populations.' 7 "18 These differences themselves may serve as either incentives or barriers to CRNAs in choosing geographical practice areas. This study serves to lay the groundwork for future examination of these factors by categorizing the vast majority of active practicing CRNAs by geographical area. Stratified sampling of CRNAs across the rural-urban continuum database should yield representative groups for future comparative analyses. REFERENCES (1) Brider P. Annual nursing salary survey: Where did the jobs go? AJN. 1993;93(4):31-40. (2) Erwin W. AHA survey: Nurse shortage eases dramatically. Hospitals. 1993;67(3):52. (3) Stratton TD, Dunkin JW, Juhl N. Redefining the nursing shortage: A rural perspective. Nursing Outlook. 1995;43:71-77. (4) Beutler JM. Other perspectives on anesthesia. Health Affairs. 1988;7(4):20. (5) American Association of Nurse Anesthetists' Department of Education and Research. AANA study of underserve4d small and rural hospitals. 1994. (6) American Nurses Association Rural/Frontier Health Care Task Force. Rural/Frontier Nursing: The Challenge to Grow. Washington, DC: American Nurses Publishing. 1996:4-7. (7) Butler MA, Beale CL. continuum codes for metro and nonmetro counties, 1993. Staff Report No. 9425, Agriculture and Rural Economy Division, Economic Research Service. US Department of Agriculture. September 1994. (8) Grundy BL, Medsger A, Silverman M, et al Characteristics of nurse anesthetists working with and without anesthesiologists. Medicare. 1987;25(12):1129-1138. (9) Gunn IP, Dunlap E. CRNAs and anesthesiologists by Texas counties. An unpublished study for the Texas Association of Nurse Anesthetists. 1992. (10) Reves JG, Rogers MC, Smith LR. Residents workforce in a time of U.S. health-care system transition. Anesthesiology. 1996;84:700-711. (11) Orkin FK. The geographic distribution of anesthesiologists during rapid growth in their supply. Anesthesiology. 1994;81:A1295. (12) Orkin FK. Why do anesthesiologists shun rural hospitals? Submitted for presentation at the annual meeting of the International Anesthesia Research Society. March 1996. (13) Orkin FK. Workforce planning for anesthesia care. Int Anesthesiol Clin. 1995;33(4):69-101. (14) Schroeder ST. Training an appropriate mix of physicians to meet the nation's needs. Acad Med. 1993;68(2):118-122. (15) Kindig DA, Libby D. How will graduate medical education reform affect specialties and geographic areas?jama. 1994;272:37-42. (16) Moses EB. RN shortage seen for 21st century, as I see it. American Nurse. 1992;24(7):4. (17) Stratton TD, Dunkin JW, Juhl N, Geller JM. Recruiting registered nurses to rural practice settings: An assessment of strategies and barriers. Applied Nurs Res. 1993;6(2):64-70. (18) Fusard B, Slocum LI, Wiggers DE. Rural nurses, II: Surviving the shortage.jnuradmin. 1990;20(5):41-46. AUTHORS Michael D. Fallacaro, CRNA DNS, received his BSN from D'Youville College, Buffalo, New York; a BS in Anesthesia from George Washington University, Washington, DC; and his master of science and doctoral s from the State University of New York at Buffalo. He is clinical assistant professor and co-director of the Nurse Anesthesia Program at the State University of New York at Buffalo. Thomas E. Obst, CRNA MS, received his BSN from Niagara University, New York, and his master of science in Nursing from the State University of New York at Buffalo. He is clinical assistant professor and co-director of the Nurse Anesthesia Program at the State University of New York at Buffalo. Ira P. Gunn, CRNA, MLN, FAAN, received her BA from Hardin Simmons University, Abilene, Texas, and her MLN from the University of Houston, Houston, Texas. She became a Fellow of the American Academy of Nursing in 1981. She serves as consultant to the Nurse Anesthesia Program at the State University of New York at Buffalo. Manqing Chu, BA, is a research assistant for the Nurse Anesthesia Program and a graduate student in Geography at the State University of New York at Buffalo. ACKNOWLEDGMENT The authors wish to acknowledge the contributions of Barbara Zon, CPS, and Kim Vazquez, RN, BSN, in the preparation of this manuscript. 242 Journal of the American Association of Nurse Anesthetists