Differences in income-related inequality and horizontal inequity in ambulatory care use between rural and non-rural areas: using the 1998-2001 U.S. National Health Interview Survey data

Abstract

BackgroundTo better understand income-related inequalities in health care use, it is imperative to identify sources of inequalities and assess the extent to which health care use is still related to income after differences in need across the income distribution are accounted for. Little is known regarding rural-urban differences in income-related inequalities and subgroup variation in horizontal inequities in health care use. This study decomposes income-related inequalities in ambulatory care use into contributions of need and non-need factors and compares horizontal inequities of subgroups in rural and non-rural areas.MethodsThis analysis used non-elderly adult samples from the 1998 to 2001 U.S. National Health Interview Survey data. The area of residence was categorized as rural for non-Metropolitan Statistical Area (MSA) and non-rural for MSA. Concentration indices of ambulatory care use were used to gauge income-related inequalities and decomposed into contributing factors. Horizontal inequities were measured using two methods and the results were compared.ResultsAmbulatory care use was disproportionately concentrated in the poor before need adjustment. However, the results of decomposition and horizontal inequity analyses indicate that the pro-poor concentration of health care use was due to greater health care need in low-income groups. Adjusting for need, ambulatory care use was distributed favoring the better-off, to a larger degree in non-rural areas. Health-related variables were the major contributors to income-related inequalities. Non-need factors, including socioeconomic factors, health insurance, and usual source of care, also contributed to income-related inequalities. There were variation in determinants' contributions to income-related inequalities between rural and non-rural populations and subgroup differences in horizontal inequities. Horizontal inequities were greater within non-whites, high school graduates, individuals with private health insurance, and those without a usual source of care with some geographic variation.ConclusionsOur analysis shows that seemingly pro-poor income-related inequalities in ambulatory care use were largely due to greater health care need among low-income groups. The results demonstrate different contributions of determinants to income-related inequalities and variation in horizontal inequities by subgroup and locale. The findings of this study should help identify targets for policy intervention for each rural and non-rural area.

Availability of health services vs. health condition of residents of rural areas in Poland – Analysis performed on the basis of EHIS 2009

“…where y i and r i mean respectively a use of health services by the i-th individual and its rank (in the form of a fraction) in the distribution of income, y is the average use of services among the surveyed respondents in the analysed period [5,6,7,8]. The index value remains in the range [-1,1].…”

“…One of the most often discussed issues related to this matter is income inequality [5,6,7,8]. The income-related inequalities refer to differences in the use of health services by persons with various levels of income.…”

Equitable Access to Health Care for the Elderly in South Korea

“…The unavoidable variation in health care utilization due to differences in health status results in income-related inequality itself being considered "non-inequity" in health care utilization (van Doorslaer et al, 2004). Therefore, to measure inequity in health care utilization correctly, the health care needs of different groups should be taken into consideration (Shin & Kim, 2010). Need for health care is defined as a person's expected use of health care services on the basis of actual need characteristics, with the effects of all other variables "neutralized" by their being set at their sample means in the prediction stage.…”

“…The concentration index approach was applied to enable decomposing the contribution of individual factors as well as error components to overall inequality in health care utilization, following the method proposed by Wagstaff, van Doorslaer, and Watanabe (2003) (Masseria & Giannoni, 2010;Shin & Kim, 2010).…”

Horizontal inequities in dental service utilization

“…의료이용의 형평성에 대한 선행연구들은 주로 집중지 수(Concentration Index, CI) [7][8][9][10][11][12][13][14][15] 와 수평적 형평성(Horizontal equity) [7][8][9][10][11][13][14][15] 을 반영한 HIwv지수(Horizontal Inequity index) 를 사용하여 측정한다. 의료이용의 수평적 형평성을 측정한 대부 분의 연구는 외래 의료서비스 및 일차의사(GP) 진료의 경우 소득 이 낮은 집단에서 유리한 불형평이 나타났고 [7][8][9][10][11][12][13][14] , 입원 의료서비 스, 전문의 진료는 빈곤층에 비해 상대적으로 부유층에서 더 빈번 한 의료이용을 보이는 것으로 보고된다 7,9,12,13) . 기존의 연구에 따 르면 외래와 입원 모두에서 고소득층의 의료이용이 많은 것으로 나타났는데 고소득층에 비해 저소득층의 의료이용의 요구(need) 가 더 많지만, 의료필요를 고려하면 소득계층별 의료이용의 격차 가 감소하는 경향을 보였다 13) .…”