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Agency for Healthcare Research Quality


Authors: Wong H., Hellinger F.
Title: Conducting Research on the Medicare Market: The Need for Better Data and Methods.
Publication: Health Services Research 2001 Apr;36(1 Part 2):291-308.
Date: 2001
Abstract: This study highlights data limitations, the need to improve data collection, the need to develop better analytic methods, and the need to use alternative data sources to conduct research related to the Medicare program. These objectives are achieved by reviewing existing studies on risk selection in Medicare HMOs, examining their data limitations, and introducing a new approach that circumvents many of these shortcomings. Data for 1995-97 for five States (Arizona, Florida, Massachusetts, New York, and Pennsylvania) from the HCUP State Inpatient Databases (SID), maintained by AHRQ and the Health Care Financing Administration's Medicare Managed Care Market Penetration Data Files and Medicare Provider Analysis and Review Files are used in this study. The authors analyzed hospital utilization rates for Medicare beneficiaries in the traditional fee-for-service Medicare and Medicare HMO sectors and examine the relationship between these rates and the Medicare HMO penetration rates. Medicare HMOs were found to have lower hospital utilization rates than their fee-for-service counterparts, differences in utilization rates vary across States, and that HMO penetration rates are inversely related to the rough measure of favorable selection. The authors conclude that substantial growth in Medicare HMO enrollment and the implementation of a new risk-adjusted payment system have led to an increasing need for research on the Medicare program. Improved data collection, better methods, new creative approaches, and alternative data sources are needed to address these issues in a timely and suitable manner.

Authors: McNamara R, Powe N, Thiemann D, Shaffer T, Weller W, Anderson G.
Title: Specialty of Principal Care Physician and Medicare Expenditures in Patients with Coronary Artery Disease: Impact of Comorbidity and Severity.
Publication: American Journal of Managed Care 7:261-66.
Date: 2001
Abstract: To explore differences in expenditures for elderly patients with acute and chronic coronary artery disease according to the specialty of the principal care physician, a total of 250,514 patients with coronary artery disease (ICD-9 codes 410-414) were drawn from a national 5 percent random sample of 1992 Medicare beneficiaries. Patients were classified by the physician type with the highest number of Medicare Part B outpatient claims into a cardiologist group and a generalist group. The outcome was mean total expenditures, stratifying (1) by comorbidity as measured by the modified Charlson Index and (2) by severity defined as the proportion of patients with acute myocardial infarction or unstable angina. Those patients in the cardiologist group had lower comorbidity and higher severity than those in the generalist group. Overall mean expenditures were significantly higher for the cardiologist group than for the generalist group ($7,658 vs $6,047; P < .001 ). These differences in mean expenditures were evident at each level of comorbidity. However, when stratified by severity of diagnosis, differences were seen pre-dominantly in those, with acute diagnoses. Expenditures were higher when cardiologists were the principal care physicians treating patients with acute disease ($15,378 vs $12,260; P < .001) compared with chronic disease where the expenditures were similar ($4,856 vs $4,745; P = .53).

Authors: Spector W., Mukamel D.
Title: Nursing home administrators' perceptions of competition and strategic responses.
Publication: Long Term Care Interface 2(3):37-41.
Date: March 2001
Abstract: This paper presents findings from a 1999 mailed survey of nursing home administrators in New York State, designed to elicit their perceptions of competition in the nursing home market and their strategic plans to cope with changing market conditions. Results show that administrators think that nursing home markets have become more competitive and expect this trend to continue. They perceive differences in the way individual customers choose nursing homes versus the way MCOs and hospitals make such choices. They believe that individual consumers place a higher value on quality of life factors, while aggregate purchasers rate price and the availability of complex sub-acute services higher. Strategic responses by nursing homes varied by ownership type.

Author: Hellinger FJ, Wong HS.
Title: Selection bias in HMOs: A review of the evidence.
Publication: Med Care Res Rev 57(4):405-39
Date: 2000
Abstract: Many studies have compared the characteristics of persons who join HMOs with those of persons who join FFS plans, and several studies have reviewed findings regarding selection bias in HMOs. This article extends the findings of previous reviews by including information from studies published through 1999. This is important because of the rapid diffusion of HMOs in all markets and recent changes in the way public programs are organizing and paying for care from HMOs. This article also examines recent changes in how HMOs are paid. This is important because recent changes in payment methodologies may reduce, or eliminate, overpayments to HMOs resulting from selection bias. For example, changes in Medicare's risk adjustment system implemented in January 2000 unquestionably mitigate the impact of favorable selection on HMO payments.
Availability: AHRQ Publication No. 01-R026 is available from the AHRQ Publications Clearinghouse.

Author: Encinosa W, Sappington D.
Title: Adjusted community rate reforms to promote HMO participation in Medicare+ Choice.
Publication: Health Care Financing Review 21(1)19-29.
Date: 1999
Abstract: The authors review the financial regulations imposed on HMOs that participate in the Medicare+ Choice program, and identify elements of the regulations that may discourage HMO participation in the program. We propose modifications of the regulations that can encourage the participation of HMOs without affording them excessive profit. The modifications include smoothing and bounding profit estimates, and authorizing and encouraging expanded use of benefit stabilization funds.

Authors: Harris-Kojetin L, Fowler F, Schnaier J, et al.
Title: The use of cognitive testing for developing and evaluating CAHPS® survey items.
Publication: Med Care 37(3 Suppl):MS10-MS21.
Date: 1999
Abstract: The main goal of the Consumer Assessments of Health Plans (CAHPS®) survey is to develop an integrated set of tested, standardized surveys to obtain meaningful information from health plan enrollees about their experiences. The CAHPS® project benefits from the complementary strengths of psychometric and cognitive testing. The authors found that cognitive testing was integral in developing and refining the CAHPS® instrument. The cognitive testing findings contributed to an improved instrument that should capture consumers' health care and plan experiences with less response error than one not subjected to such testing.

Authors: Schnaier J, Sweeny S, Williams W, et al.
Title: Special issues addressed in the CAHPS® survey of Medicare managed care beneficiaries.
Publication: Med Care 37(3 Suppl):MS69-MS78.
Date: 1999
Abstract: This article describes the process through which the Medicare Managed Care plan (MMC) survey was developed and examines issues in using this survey with Medicare beneficiaries that have implications for all CAHPS® surveys. These implications include the ability of Medicare beneficiaries to use MMC navigational features, whether access measures are meaningful for this population, and whether beneficiaries' familiarity with managed care influences their health plan assessments.

Author: Hellinger F.
Title: The effect of managed care on quality: A review of new evidence.
Publication: Archives of Internal Medicine 158:833-41.
Date: 1998
Abstract: This article reviews recent evidence about the relationship between managed care and quality. With one exception, the studies reviewed represent observation periods that extend through 1990 or a more recent year. The review has led to the conclusion that managed care has not decreased the overall effectiveness of care. However, evidence suggests that managed care may adversely affect the health of some vulnerable subpopulations. Evidence also suggests that enrollees in managed care plans are less satisfied with their care and have more problems accessing specialized services. In addition, younger, wealthier, and healthier persons were more satisfied with their health plans than older, poorer, and sicker persons, even after adjusting for the type of health plan. The findings of the studies reviewed do not provide definitive results about the effect of managed care on quality. Indeed, relatively few studies include data from the 1990s, and little is known about the newer types of health maintenance organizations that invest heavily in information systems and rely on financial incentives to alter practice patterns. Furthermore, managed care is not a uniform method that is applied identically by all health plans, and research studying the different dimensions of managed care also is needed.
Availability: AHCPR Publication No. 98-R056 is available from the AHRQ Publications Clearinghouse.

Author: Hellinger F.
Title: Regulating the financial incentives facing physicians in managed care plans.
Publication: American Journal of Managed Care 4(5):663-74.
Date: 1998
Abstract: Recent accounts of enrollees in managed care plans being denied access to potentially lifesaving services have heightened public anxiety about the impact of managed care on the accessibility and appropriateness of care, This anxiety has been translated into legislative action. The present review focuses on an area of managed care operations that has received considerable attention in State legislatures and in Congress during the past 2 years: the financial relationship between managed care health plans and physicians. Twelve States now mandate that managed care plans disclose information about their financial relationship with physicians, and 11 States regulate the method used by managed care health plans to compensate physicians. Most laws that regulate methods of compensation prohibit health plans from providing physicians an inducement to reduce or limit the delivery of "medically necessary" services. Moreover, in 1996 the Health Care Financing Administration (HCFA) finalized its regulations governing the financial incentives facing physicians in plans that treat Medicaid or Medicare patients, and these regulations went into effect on January 1, 1997. These regulations are also examined in this study.
Availability: AHCPR Publication No. 98-R064 is available from the AHRQ Publications Clearinghouse.

Authors: Miller M, Welch W, Wong H.
Title: Exploring the relationship between inpatient facility and physician services.
Publication: Med Care 1997;35(2):114-27.
Date: 1997
Abstract: Available on PubMed®
Availability: AHCPR Publication No. 97-R045 is available from the AHRQ Publications Clearinghouse.

Authors: McCormack L, Schnaier J, Lee A, et al.
Title: Medicare beneficiary counseling programs: What are they and do they work?
Publication: Health Care Financing Review 18(1):127-40.
Date: 1996
Abstract: Medicare beneficiaries face myriad rules, conditions, and exceptions under the Medicare program. As a result, State Information, Counseling, and Assistance (ICA) programs were established or enhanced with Federal funding as part of the Omnibus Budget Reconciliation Act (OBRA) of 1990. ICA programs use a volunteer-based and locally-sponsored support system to deliver free and unbiased counseling on the Medicare program and related health insurance issues. This article discusses the effectiveness of the ICA model. Because the ICA programs serve as a vital link between the Health Care Financing Administration (HCFA) and its beneficiaries, information about the programs' success may be useful to HCFA and other policymakers during this era of consumer information.

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