We found that clinical performance for preventive services and chronic disease management improved within the IHS for most performance measures. Primary care physicians reported substantial barriers in access to essential health services, and these reports were modestly correlated with lower performance on some measures of clinical quality. We did not find substantial differences in quality between rural and urban settings, confirming prior analyses within the IHS
24, and suggesting that an integrated delivery system can ensure equivalent care across varied health care settings.
Substantial disparities in clinical performance persisted between the IHS and health plans participating in Medicare and Medicaid, particularly for screening mammography and diabetic retinopathy screening, two measures for which the IHS ranks below the 25
th percentile of these health plans nationally. However, the IHS performed better than many health plans for other measures of diabetes care including annual HbA1c and LDL cholesterol testing, and the IHS performance exceeded the 90
th percentile for adult pneumococcal vaccination
25.
The Medicare program represents a national benchmark for quality of care across a variety of delivery systems
26, and ultimately should represent a minimum achievement target for the IHS. Comparisons to the Medicaid program provide additional insight as Medicaid is focused on ensuring care for underserved low-income populations, and its funding levels more closely reflect those of the IHS. Our data suggest that quality of care within the IHS parallels that within the Medicaid program more closely. This observation may reflect similarity in patient characteristics or funding levels, though it is important to note that Medicaid expenditures per person are higher than those within the IHS
11.
We found that primary care physicians caring for Native American patients reported suboptimal access to essential health services to a much greater extent than physicians caring for either white or black patients
19,20. The IHS remains significantly underfunded, receiving only about half of the funding needed to adequately care for the patients it serves
11,27. This budget shortfall could lead directly to the type of stark resource limitations reported by the physicians in this study. For example, 76% of primary care physicians caring for black patients report adequate access to subspecialists
19, compared to 29% of physicians in the IHS. As a result, a majority (58%) of primary care physicians within the IHS report that complexity of clinical conditions managed without specialty input was greater than it should be, compared to only 26% of physicians caring for black and Hispanic patients
20. These physician reports are further substantiated by the increasing number of out-of-network patient services denied due to lack of funding within the IHS, which rose by 68% from 2003 to 2006 (T. Cullen, written communication, August 6, 2009). Despite reporting substantial challenges to delivering care, a majority of physicians felt they were able to deliver high quality care. This divergence is likely related to physicians defining high quality care outside of the domains of care assessed in our study
28,29.
As the IHS received a 13% increase in funding in FY2010
30, it is important to understand how such a substantial increase in funding might be best utilized. Our findings indicate several areas on which to focus, including increasing access to subspecialty and imaging services, physician recruitment, expanded use of health information technology, and improved chronic disease management strategies.
The importance of the first two areas is highlighted by our survey findings and clinical performance data. Physicians’ reports of inadequate access were significantly correlated with low clinical performance for mammography and a similar trend for diabetic eye exams. These findings likely reflect a scarcity of equipment or trained personnel to perform screening mammography and dilated eye exams. Access to these and other types of specialty services
23 could most directly be addressed through contract health services, which received an 18% increase in the IHS FY2010 budget, but will likely require additional increases to meet the substantial need. Additional work is also needed to understand how to improve screening rates among clinics already reporting good access to essential services, highlighted by the suboptimal rates of mammography and diabetic eye exams among clinics with physicians reporting good access to these services. This effort will likely involve an examination of the role of social, community, and other patient factors that relate to delivering high quality care.
Recruiting qualified personnel to work in the IHS is also important, and the IHS currently has vacancy rates of 21% for physicians
10. Promoting the training of Native American health professionals who may be more inclined to work in these settings is one strategy to address this unmet need
31. Our survey identified that 14% of physicians working within the IHS were Native American, compared with less than 1% of medical students who are Native American
32.
Our data also suggest that expanding the use of health information technology represents a promising strategy. The low rates of screening diabetic eye exams are particularly troubling given the burden of disease among this population. The use of a tele-ophthalmology program has increased performance of screening diabetic eye exams within the IHS, ultimately resulting in increased rates of laser therapy to prevent blindness without the need to recruit additional ophthalmologists
33. This and other health information technology-based strategies such as dissemination of an advanced electronic health record
13 represent attractive solutions to overcome both the financial and geographic barriers faced by the IHS.
Our study has some limitations. We presented national comparison data for the IHS, but were not able to adjust clinical performance rates for differences in age distributions between the IHS patient population and the Medicare and Medicaid populations. We also did not analyze care among tribally operated facilities. While the option to convert to tribally operated management has existed since 1975, many clinics have transitioned only in recent years
9, and many of the issues identified by physicians in our survey are likely independent of this administrative change.
In addition, while the IHS provides health care for a substantial proportion of Native Americans in the United States, many Native Americans receive care outside of this system, particularly in urban areas. Future work is needed to better understand the state of health care delivery for these other segments of the Native American population. Finally, while we analyzed care according to rural residence, we were not able to identify whether patients resided on tribal reservations, which may present unique challenges to health care delivery such as limited access to electricity, indoor plumbing or telephone services.
In this large-scale assessment of care delivered within the Indian Health Service, we identified both significant quality improvement along with persistent barriers to delivering high-quality care to Native American patients. While the Indian Health Service is actively engaged in a variety of quality improvement programs, true advances in health care delivery and health outcomes may ultimately be limited by resource constraints. Further research is needed to understand and address the long-term impact of these constraints on the health of Native Americans.