Decomposing area of residence differences in multiple regression studies: the relative contributions of independent variables and model coefficients.

When rural/urban differences are found in health status or health care use, it is often desirable to identify those factors (such as age, social structure, income, etc.) that influence such differences. To this end, researchers often test rural/urban differences in age, social structure, income, etc., for statistical significance. Also, researchers commonly perform multivariate analyses (such as multiple regressions) to examine rural-urban differences in the influence of various independent variables on the dependent variable of interest. Frequently, researchers discover: (1) statistically significant rural/urban differences in the independent variables (such as age, social structure, income, etc.) and (2) statistically significant rural/urban differences in the effects of these independent variables (i.e., statistically significant rural/urban differences in regression coefficients). The analysis typically stops here, without addressing the relative contributions of (1) and (2) to the rural/urban differences in the dependent variable. This paper argues that the relative contributions of (1) and (2) have important implications for the way policy-makers address rural health problems. This paper presents a method for assessing the relative contributions of differences in the independent variables and differences in regression coefficients to observed differences in the dependent variable, and illustrates the application of the method by analyzing rural/urban differences in the risk of institutionalization.

Area of residence and the risk of institutionalization.

Many of the sociodemographic, health status, and social support characteristics that predict the use of health services by elders vary by area of residence. Yet, little is known about how these factors affect the risk of institutionalization in rural, small city, and urban areas. The purpose of this research was to: (a) determine the rate of institutionalization over a two-year period for impaired community-dwelling elders in rural, small city, and urban areas; (b) test for residence differences in sociodemographic, health status, and social support characteristics likely to influence the risk of institutionalization; and (c) examine their effect on the probability of being institutionalized in each area of residence. Although rural elders are less likely to be placed in a nursing home than their small city or urban counterparts, race and level of impairment affect the risk of institutionalization more in rural than in urban areas.

Uncompensated care provided by private practice physicians in Florida.

While a great deal of attention has been paid in recent years to establishing the magnitude and characteristics of uncompensated care in hospitals, comparatively little research has been undertaken to study physician uncompensated care. This article reports the results of a prospective patient-specific study of uncompensated care in Florida. Of 4,042 cases examined, 26.2 percent had charges voluntarily reduced below the usual and customary charge at the time of service. However, only 13.5 percent of those reductions were attributed to charity. Overall, 10.4 percent of the total billed amount was left unresolved. When payment source was considered, it was found that self-pay patients accounted for 30.6 percent of the cases but accounted for 52.0 percent of the unresolved amounts. Further analysis indicated that the self-pay patients were 35.5 times more likely to leave an outstanding balance than individuals with some type of insurance coverage. Odds of unresolved balances were also calculated as a function of income, specialty type, practice size, and type of visit.

Determinants of primary caregiver stress and burden: area of residence and the caregiving networks of frail elders.

This research examines the association among characteristics of the caregiving network, primary caregiver stress and burden, and area of residence. The purpose is two-fold: to determine whether the structure of the relationship between the caregiving network, and stress and burden is uniform across rural, small city, and urban samples; and, to assess whether stress and burden are explained by a similar set of variables within area of residence categories. The data are drawn from a matched sample of 1,388 impaired elders and their primary caregivers from the 1982 National Long-Term Care Survey and the National Survey of Informal Caregivers. In general, the analysis shows that several characteristics of the care-receiver and the primary caregiver have a differential effect on stress and burden across residential categories, and that, within rural, small city, and urban samples, the determinants of stress and burden are not homogeneous. When the frail elder is able to reciprocate by doing chores, babysitting, or providing some other type of assistance for the primary caregiver, however, both stress and burden are reduced in all three residential categories. Similarly, the increased provision of assistance with instrumental activities of daily living by the primary caregiver uniformly increases stress and burden. These findings suggest that interventions designed to alleviate primary caregiver stress and burden may be able to have some common components, but may also need to be tailored in some ways to specific residential environments.

Impact of a required family medicine clerkship on medical students' attitudes about primary care.

A study of 314 medical students before and after a required third-year clerkship in family medicine explored relationships among exposure to the clerkship and changes in attitudes toward primary care. The survey instrument contained 29 statements distinguishing the philosophy of primary care from that of subspecialty-oriented medicine and asked students' to state their future residency plans. The responses of the primary care and subspecialty-oriented groups were the most disparate, whereas the students who were uncertain about residency plans shifted on several items from an alignment with the specialty group toward an alignment with the primary care group. This study shows that experience in a family medicine clerkship may be associated with changes in attitudes that represent development of a more informed image of primary care.

Medical students and comprehensive patient care: attitudes, perceived competence and demonstrated ability.

The importance of medical training which emphasizes comprehensive, biopsychosocial medical care is increasingly recognized. Research has focused on characteristics affecting attitudes toward psychosocial information, inferring that such attitudes are acceptable surrogates for demonstrated ability. The current study evaluates the accuracy of information elicited during medical interviews conducted by medical students. Information regarding patient compliance, patient income and patient reliance on social support was correlated with student characteristics, attitudes toward psychosocial information and self-perceived competence in eliciting such data. For 36 third-year medical students on a 4-week family medicine rotation, results showed that measures of psychosocial attitudes were not an acceptable substitute for demonstrated ability. Exposing medical students to the importance of psychosocial data is valuable, but additional attention must be given to their eliciting such information accurately and efficiently.