The validity of indices for rural health manpower needs assessment

Evaluation and Program Planning, Vol. 6, pp. 139-142, Printed in the USA. All rights reserved.

1983 Copyright

0149-7189/83 $3.00 + .OO 0 1984 Pergamon Press Ltd

THE VALIDITY OF INDICES FOR RURAL HEALTH MANPOWER NEEDS ASSESSMENT

GEORGEE. FRYER, JR., RICHARDL. CALL, CAROLEHEINE, and PAUL CASAMASSIMO University

of Colorado

ABSTRACT Population-to-practitioner ratios have long been the primary index in the designation of health manpower shortage areas. This paper documents that application of the widely used population-to-dentist index results in understatement of the need for dental health manpower in rural areas. Through the analysis of utilization data collected from a statewide health screening program in Colorado, the practice of sole reliance on the population-to-dentist indices as an indicator of need was tested. Another measure, the area- (square miles) to-dentist ratio was formulated, examined, and found to be a more useful referent of the needfor additional health manpower in rural areas. Utilization of dental services in sparsely settled rural counties of Colorado was unrelated to population-to-dentist ratios. A strong, statistically significant association of utilization with land area-to-dentist ratios was found. The findings of this analysis suggest a need for reevaluation of needs assessment methodologies used in the designation of health manpower shortage areas. Indices more sensitive to consumer circumstance than to the number of health care providers available must be considered.

INTRODUCTION dication of underservice, has in recent years pressed the University of Colorado School of Dentistry to justify its existence. It has also stricken from the budget of SEARCH, the University’s area health education center program, funding previously allocated for the preceptorship of dental students by dentists practicing in rural areas. Thirteen of Colorado’s 63 counties (20.6%) have at least one community of 10,000 persons or more and are considered urban. Of the 16 counties with the most favorable population-to-dentist ratio (less than 1,550: 1) in the state, 4 (25%) have at least one town of 10,000 residents. Thus, this comparison would seem to reflect relatively equal distribution of dentists between urban and rural areas. Population-to-practitioner ratios have become the cornerstone of health manpower needs assessment. Widespread use of other referents, such as utilization rates, which usually require costly primary data collection, is simply not feasible. Thus, considerations seldom have real bearing on the decision to award or withhold a dentist manpower shortage area designa-

Health manpower resources have been geographically maldistributed throughout this country for many years. Since the publication of a Carnegie Council on Higher Education in Medicine and Dentistry report (1970) which portrayed the nature and impact of this problem in rural areas of the United States, a number of federal and state programs have been implemented in an effort to address this matter of serious public concern. Health manpower needs have been assessed periodically in Colorado for the purpose of identifying areas of underservice. Typically, this process has culminated in the award or withdrawal of federal designation of an area (county, minor civil district, or census civil district) as a health manpower shortage area. For dentists, a population-to-practitioner ratio of 5,OOO:l is the primary criterion of designation (Department of Health, Education and Welfare, 1978). In Colorado, of the state’s 63 counties, only 3 entire counties and parts of another 2 have been designated dental health manpower shortage areas. The state legislature, in the absence of any strong in-

Requests for reprints should C-241, Denver, CO 80262.

be sent to George

E. Fryer,

University

of Colorado

139

Health

Sciences

Center,

4200 E. 9th Ave.,

Campus

Box

G. E. FRYER,

140

tion. Our findings, however, seriously call into question the wisdom of almost sole reliance on this indicator of need. This paper examines the validity of the position that

JR. et

al.

dental services are equally accessible to rural and urban Colorado residents, and the unqualified application of population-to-dentist ratios in the assessment of small area health manpower needs.

METHODS Data used in this analysis were gathered during a statewide health fair held in the spring of 1981. The health fair was privately sponsored and open to all residents of the state during a l-week period. The purpose of the health fair was general health screening, of which oral screening was one segment. Participation by the population in each segment of the fair was voluntary. Seventy of the 150 screening sites held oral screenings as a part of the general health screening process. The oral screening sites were distributed throughout the state with the choice to hold an oral screening being made by the local site coordinator. Of the 150 sites, 36 were located in rural Colorado. All participants in the oral screening process were asked to complete a questionnaire prior to the profes-

sionally administered oral screening examination. The questionnaire, addressing eight items related to attitudes, dental health behaviors, and demographic factors, was designed in a closed-ended question format. Over 7,000 questionnaires were returned for analysis. Zip code of residence was reported for 5,925 respondents. The respondent group was found to be representative of the adult population of the State of Colorado in age, level of education, and geographic distribution with respect to urban vs. rural residence. The constraints to interpretation of the meaning of the findings, which must be attributed to unavoidable methodological shortcoming, will be fully discussed later.

FINDINGS Table 1 portrays the contrast in utilization of dental services between rural and urban Coloradoans during the year preceding their participation in the health fair. Only 43.6% (2,237) of all participants living in a standardized metropolitan statistical area (SMSA) had not visited a dentist in that period. Fifty-four percent (426) of the non-SMSA residents had not seen a dentist during those 12 months. The resultant raw chi-square value of 30.109 yields a p-value of zero, which attests to the dependency of dentist visitation on rurality of respondent. This statistically significant finding directly contradicts the widely held view that dental services in Colorado are equally accessible to the state’s rural and urban populations. National Health Interview Survey (Department of Health, Education and Welfare, 1980, pp. 46-50) data document that the affluent and better educated receive

UTILIZATION

OF DENTAL

TABLE 7 SERVICES

more dental care than do persons of lower socioeconomic status. This implies that dental services are either unaffordable to or less valued by members of the latter group. Both income and education levels (median years of family education and median family income) are markedly lower among rural counties than among SMSA counties of the state. This suggests that at least some of the differential in utilization seen in Table 1 could be attributed to a lack of financial

BARRIERS

TABLE 2 TO ACCESSIBILITY

Finances are a barrier #

SMSAa residents Non-SMSA

residents

Total +SMSA

= standardized

%

#

%

Total -

(16.7)

4,276

(83.3)

5,136

Non-SMSA

149

(18.9)

840

(81.1}

789

1,009

(17.0)

4,916

(83.0)

5,925

Have interest in dental care -

Total -

residents

IN THE PAST YEAR Had not visited dentist in past year

Lack interest in dental care

Total

%

#

%

2,899

(58.4)

2,237

(43.6)

5,136

363

(46.0)

426

(54.0)

789

Non-SMSA

5,925

Total

metropolitan

Finances are not a barrier -

860

#

3,262

CARE

SMSAa residents

Total Had visited dentist in past year

TO DENTAL

2,663 statistical

area

SMSA

aSMSA

residents residents

= standardized

#

%

#

%

120

(2.3)

5,016

(97.7)

5,136

11

(1.4)

778

(98.8)

789

131

(2.2)

5,794

(97.8)

5,925

statistical

area

metropolitan

Rural Health Manpower Needs Assessment TAELE3 RURAL COUNTY POPULATION-TO-DENTIST RATIOS AS AN INFLUENCE OF UTILI~TION OF DENTAL SERVICES Had not Had visited dentist in past year # Residents of ruraf counties with ratios more favorable (less) than 156O:l Residents of rural counties with ratios Less favorabfe (greater) than 755O:l Total

Q/Q

visited dentist in past year #

%

Total

146

(45.2)

177

(54.6)

323

105 -

(45.5)

126 -

(54.5)

231 -

151

303

554

means and interest in dental health on the part of rural Coloradoans, rather than short supply or geographic maldistribution of dental care providers. These more attitudinai aspects of demand were indirectly addressed by certain of the items of the questionnaire that each health fair participant was asked to complete. Table 2 depicts the result. Finances were reported to be a barrier to dental cart for 17.0% (1,009) of the respondents. Their impact was slightly more prevalent among rural persons (149, or 18.9%) than urban residents (860, or 16.7%). Only f 1 fl,4%f rural persons and 120 (2.3%) urban participants expressed disinterest in dental care. This information indicates that factors other than economic barriers and the

TABLE 4 RURAL COUNTY AREA (SQUARE MILES) TO DENTIST RATIOS AS AN INFLUENCE OF UTILIZATION OF DENTAL SERVICES Had visited dentist in past year

Residents of rural counties with ratios more favorable (less) than 500:f Residents of rural counties with ratios less favorable (greater) than 500:f Total

Had not visited dentist in

past year

Total

#

%

#

%

115

(35.7)

162

(61.3)

297

136 -

(52.9)

122 -

(47.1)

257 -

25f

303

554

14%

perceived value of dental care explain much of the variance in rural and urban utilization rates. The validity of the population-to-dentist ratio as a measure of under service was first tested. Table 3 contains the result. Among the more rural counties of the state (counties with no towns of at least 10,000 population), those with better population-to-dentist ratios (1,550: I or lower) demonstrated no higher utilization of dental care services than counties with fess favorabIe ratios. Indeed, 45.5070 of health fair participants from the former group had seen a dentist within the last year compared with 45.2% from the relatively dentist-rich counties. As the difference in utilization rates between rural counties cannot be explained with the conventional population-to-practitioner index, another index of geographic distribution of manpower was then postulated and examined. Specifically, analysis of this index tested the hypothesis that the physical distance of the patient from the dentist’s office may be a significant factor in the utilizatjo~ differential. The index consisted of a ratio of the area of a county in square miles to the number of dentists practicing in that county. It was earlier noted, when using the conventional population-to-dentist index, that only 4 of the 13 urban counties were among the 16 Colorado counties with the most favorable ratios, Of the 13 urban counties in Colorado, all but 1 are among the 16 counties of the state with ratios more favorable (less) than 500 square miles to one dentist. Of the remaining 50 counties, all of which are rural, all but 4 have area-todentist ratios less favorable (greater) than 500 square miles:one dentist. Whereas population-to-dentist ratios were previously shown to have had no effect on utilization, Table 4 illustrates that area-to-dentist ratios have a clear statistically significant relationship to utilization rates. Only 38.7% of rural participants living in a county for which there is less than one dentist per 500 square miles had visited a dentist in the last year. On the other hand, 52.9% of those residing in a rural county with more than one dentist per 500 square miles had seen a dentist in the last year (chi-square = 11.210 and p-value = 0). In counties with communities of 10,000 or greater, it could be argued that the majority of the population is concentrated in the larger towns, and that area-todentist ratios have little meaning. But in counties with no town of at least 10,000 people, and particularly in those with no cornrnn~jt~ of 2,500 or more, no such concentrations of population exist. Less populated rural counties suffer from the most severe problems of accessibility to dental care. The fact that in 1970, 21.5% of all Coloradoans resided in places of less than 2,500 population argues for use of an index such as area-per-dentist ratios in rural area dentaf manpower needs assessment.

142

G.

E. FRYER, JR. et al.

DISCUSSION An appreciation for shortcomings inherent in the collection of data in these refativefy uncontrolled settings is essential to understanding the limitation of application of our findings. The chief objective of gathering information at the health fair sites was documentation of service rather than the conduct of research. Therefore, although the sociodemographics of service recipients closely approximate those of the population of Colorado, they may differ in other characteristics which influence utilization of dental services. In addition, individuals who attend health fairs may by their attendance be demonstrating more interest in health care than there is to be found among the general population. There are few opportunities to inexpensively survey a large number of health care consumers as was done in conjunction with this health fair. For certain analyses, however, the size of the health fair population was small enough to dictate some methodological variance from accepted practice. In order to establish categories of suitably comparative size, rural participants were classified by population-to-dentist ratio of greater than vs. less than 1,550: 1 of county of residence. This ratio is not the criterion for adequate dental care. Its use merely permitted the creation of comparison groups of approximately equal size. In summary, there is need for further research of this issue. But just as the conventional wisdom has been seriously called into question in the designation of medically underserved areas (Newhouse, Williams, Bennett, & Schwartz, 1%X2),our findings argue for reevaluation of that process for other disciplines as well. Two premises upon which application of populationto-dentist ratios is predicated are contradicted by our findings. The first is that this index is associated with accessibility to service. In fact, population-to-~ractitioner ratios are only a proxy measure for more valuable utilization rates in the conduct of health manpower needs assessment. The former is used in lieu of utilization rates only because utilities data are very expensive to collect and, therefore, seldom available. Manpower and population data, although sometimes

dated, are usually readily available for use by the analyst. The second premise implied in the use of populationto-dentist ratios is that the most critical factor limiting a population’s accessibility to dental service is the amount of time local dentists have to practice. Essentially, the solution to inaccessibility in this scheme is provision for more practice time by attracting additional dentists to the area, or by increasing the number of visits accommodated by dentists already in service in the area. Total preoccupation here is with the capacity of dental manpower, that is, the supply factor to the virtual exclusion of consumer oriented considerations. While this fo~ulation may prove adequate for assessing dentist manpower needs in an urbanlsuburban setting, it is clearly less effective when applied in rural areas. In these cases, consumer related issues such as physical distance of the patient from the dentist’s office become a significant determinant of utilization rates. The use of an area-t~practitioner index with inexpensive, readily available data seems from our analysis to be singularly superior to Ihe exclusive use of the population-to-practitioner index in the assessment of rural health manpower needs. There are important health care policy implications for these findings. Health professional educators in this state have in the past effectively addressed the needs of underserved populations through successful student extramural programming (Call, Fryer, & Schooley, 1981). The use of new indices may permit them to better identify geographic areas of need and then arrange for the preceptorship of students by practitioners already in service to these newly determined populations. Educators can also utilize an index such as the area-to-practitioner ratio to better prepare students to assess the need for their own professional services in rural areas. This index, however, was found only to be an effective referent of the need for service. It does not document financial viability of practices established in response to that need. State and federal legislators may, therefore, choose to continue financial assistance to practices in such areas of need.

REFERENCES CALL, R. L., FRYER, G. E., JR., & SCHOOLEY, E. The role of dental education in the distribution of dental personnel. Journal of Public Heaiih De~~fis~ry,1981, 41, 245-254. CARNEGIE COUNCIL ON HIGHER EDUCATION IN MEDICINE AND DENTISTRY. Higher educution and the nation’s health: Policies for medical and dental education. New York: McGraw-Hill, 1970. DEPARTMENT OF HEALTH, PUBLIC HEALTH SERVICE.

EDUCATION, AND WELFARE; Health manpower shortage areas:

Criteria for 1590-1591.

designation.

Federal

Register,

January 10,

1978,

DEPARTMENT OF HEALTH, EDUCATION AND WELFARE; PUBLIC HEALTH SERVICE. Urnred States h&Z&- 1980 (DHHS Publication No. [PHS] 81-1232). Washington, DC: US Government Printing Office, 1980. (Survey) NEWHOUSE, SCHWARTZ, ffre Amer&n

J. P., WILLIAMS, A. P., BENNETT, W. B. Where have all the doctors gone?

V. W., & Juurnat of

Medical Associution, 1982, 247, 2392-2396.