Managed Care Research Paper

Managed care is often thought of as a U.S. institution, operating in the private, voluntary insurance market and associated with the delivery of personal health-care services. Since the early 1990s, however, several countries, including Great Britain, the Netherlands, Germany, Israel, France, and several Latin American countries have formally incorporated elements of managed care into their health systems. Other countries are contemplating such changes.

Finally, managed care tools, although primarily associated with the delivery of personal health-care services, draw heavily on public health concepts. Managed care plans both finance care and attempt to manage the health (and expenditures) of their enrolled populations, unlike conventional insurers, which principally finance the care of individual patients. Managed care plans make use of epidemiology, prevention research, and cost-effectiveness analysis to achieve these population-oriented ends.

Elements Of Managed Care

Managed care plans include a range of distinctive elements. Plans combine and modify these elements over time and across settings.

Provider Selection And Organization

Conventional insurers do not contract with specific healthcare providers. Rather, they reimburse enrollees for care provided by any provider, often based on usual and customary payment rates. By contrast, most managed care plans do contract with a network of providers. Several of the earliest managed care plans were almost fully vertically integrated organizations, in which a limited number of hospitals and physicians were employees of organizations that took on insurance risk. These plans are often referred to as ‘staff model’ HMOs. Closely related to these plans are those (often referred to as ‘group model’ HMOs) in which a fixed group of physicians (and sometimes hospitals) contracts exclusively with an organization that takes on insurance risk. Most group and staff model HMOs are not-for-profit.

Several HMOs that use staff and group model approaches have recently been established in Switzerland. Germany and the region of Catalonia in Spain are experimenting with physician networks and integrated delivery approaches that follow this type of HMO model. Most U.S. plans today contract with independent providers, who may hold contracts with many managed care organizations and may also treat patients who hold conventional insurance. The most common form of this type of managed care is the PPO, in which plans negotiate discounted rates with a defined panel of providers and also permit members to seek care outside the network (though at higher coinsurance). Some European countries are considering the implementation of PPOs, but most plan to begin with the introduction of fully integrated delivery systems after experimenting with managed care tools in their traditional health-care systems.

Managed care plans have the opportunity to select the physicians, nonphysician providers, hospitals, and pharmaceuticals included in the plan. In principle, they make this selection by choosing the highest quality and lowest cost providers. There is only limited research examining the characteristics of providers who are selected into plans. In the United States, participating physicians are more likely to be board-certified than the national average; they may also have low-cost practice styles.

Paying Providers

Because managed care plans contract with providers, they can use a wider range of payment methods than can conventional plans. Plans may pay physician providers using salaries, fee-for-service, and capitation. They may pay hospitals using case rates, such as diagnosis-related groups, or per diem rates. Plans may also combine these mechanisms, as well as bonuses, including payment for performance, withholds for excessive service use, and other incentives, into tailored incentive schemes.

In fully vertically integrated plans, physicians are often paid using salaries. Many managed care plans pay physicians on a (discounted) fee-for-service basis. Denmark and the Netherlands use a mix of fee-for-service and capitation in their health-care systems.

Under capitation payment, providers receive a fixed periodic payment for each patient they enroll. They can earn more if they enroll more patients, as long as the capitation fee exceeds expected costs. If capitation payments are driven too low, physicians may refuse to enroll patients under capitated contracts, forcing a return to other payment forms.

Capitation arrangements vary according to the scope of services covered within the capitation contract. Under broad capitation arrangements, providers may also be financially responsible for the costs of services obtained through referral or hospitalization. If the scope of services is very narrow, providers paid a capitation fee have incentives to refer patients to other providers whose services fall outside the capitation fee. In consequence, capitation contracts with narrow service coverage often incorporate additional mechanisms to restrict referrals.

Plans can also combine these payment mechanisms. For example, plans may pay fee-for-service rates but withhold a portion of the payment if use exceeds a predetermined level. A recent trend in physician reimbursement is the use of pay-for-performance, which can be seen as a combination of a capitation base payment and fee-for-service payments tied to the achievement of agreed objectives. In these arrangements total reimbursement depends on the achievement of specific performance measures (clinical measures, patient satisfaction, and information technology implementation).

Pay for performance methods have garnered considerable interest outside the United States. Israel plans to make physicians accountable for quality of care and is contemplating putting physicians at financial risk for the health-care expenditures they generate. The UK introduced pay-for-performance for physicians in 2004. Family practitioners entered into contracts with the government that will provide additional payments for high-quality care.

Monitoring Service Utilization

Managed care plans may place limits on what providers can do. Through monitoring service use, plans can reduce the cost of care and may also improve (or reduce) the quality of care. The strategies used by plans may incorporate payment incentives, feedback mechanisms, and support services.

One way to monitor service utilization is through the use of ‘gatekeeper’ arrangements. Under these arrangements, enrollees can only use specialty services if they obtain a referral from a specified primary care physician or other designated referral source. Under gatekeeper arrangements, primary care doctors can be held responsible for the level of specialist use of their enrollees.

Gatekeeping has been applied in various countries (e.g., Germany and the Scandinavian countries); however, studies that evaluate its impact are rare and variable, particularly because of the heterogeneity of gatekeeping approaches. Some evidence suggests that health-care expenditures increased more slowly in countries with gatekeeping systems. In Switzerland studies have shown a decrease in costs by 7% to 20% as a result of gatekeeping.

Most managed care plans also monitor service utilization directly. Plans may refuse to pay for services unless authorization is obtained in advance. They may also monitor resources concurrent with use or retrospectively. Research suggests that UR may reduce hospital expenses by about 7% to 10% although the results are not unequivocal. Except as an element of gatekeeping, UR is not used widely outside the United States.

Many managed care plans use case management, especially for high-cost cases. Case management may involve using support services to ensure that medical care is delivered to patients in the least costly way. Case management may also use support services to improve the quality of care provided to patients. There is little evidence demonstrating the effectiveness of case management in reducing costs, although some evidence, including studies in both the United States and Europe, suggests that it may improve health-care quality in selected situations. A more recent innovation is disease management, in which the care of patients with a specific set of diseases is managed by a separate team. Disease management is an increasingly popular element of U.S. health insurance plans and has been introduced in Germany, the UK, and Switzerland. To date, there are few rigorous studies evaluating the effectiveness of disease management. Some evidence supports its role in the care of patients with type 2 diabetes.

Quality Monitoring

The emphasis in managed care plans on limiting unnecessary care through selective contracting, utilization management, and payment incentives, generated concerns that managed care undermined the quality of medical care. Plans, seeking to gain members, wanted to disprove this contention. At the same time, the ability of plans to measure outcomes within a defined population made it easier to assess the quality of care provided.

These developments generated a movement toward quality measurement. The U.S. National Committee for Quality Assurance (NCQA), a private not-for-profit organization, began accrediting managed care organizations in 1991. NCQA requires accredited plans to undergo rigorous evaluation and, beginning in 1992, to measure outcomes according to a standard based on the Health Plan Employer Data Information Set (HEDIS). The over 60 HEDIS measures include both clinical outcomes and patient satisfaction. NCQA and other organizations continue to refine quality measures, which are essential components in pay-for-performance initiatives.

Preventive Health-Care Benefits

Managed care plan contracts in the United States are more likely than other types of private insurance plans to cover preventive and maternity services. In all contexts, managed care plans tend to place a heavy emphasis on prevention. Managed care plans benefit from keeping their beneficiaries healthy as overall health-care costs to the plan may be reduced. Unfortunately, whereas many preventive health-care services are cost-effective, relatively few reduce medical care costs for the plan (at least in the short term). Moreover, plan members can, and often do, change plans well before the benefit of preventive interventions would be realized. Even if these benefits do not save money for managed care plans, offering generous preventive benefits may improve the health of their covered populations, helping them to attract additional members. Moreover, generous preventive care benefits may, themselves, be especially attractive to healthier than average populations.

Special Cases: Behavioral Managed Care And Pharmaceutical Benefits Management

Managed care principles have proven especially effective in the delivery of specific types of health care. For example, managed care arrangements have been used for the provision of disease-specific care and pharmaceutical benefits.

The most important of these ‘carve-out’ models of managed care is the managed behavioral health-care plan. Employers, governments, and some general managed care plans often contract with a separate behavioral health-care plan to provide management of behavioral health (mental health and substance abuse treatment) services to their enrolled populations. Behavioral health carve-out plans have several advantages over traditional indemnity insurers and general managed care plans. First, these plans contract with a specialized group of providers, who are generally quite distinct from general health providers. Specialized plans can develop expertise in the selection and monitoring of these providers. Second, this same specialized expertise makes behavioral health carve out plans adept at monitoring mental health and substance abuse treatment. Indeed, utilization management has had its largest effects in this sector. Finally, contracting all behavioral health services to a single carve-out plan avoids problems of selection that often plague the delivery of mental health benefits in competitive insurance markets. Behavioral health conditions tend to be chronic and costly, leading to substantial self-selection into plans with generous benefits. In the absence of a specialized carve-out plan, general health insurers tend to avoid covering behavioral health services at all. The carve-out arrangement permits purchasers to maintain generous behavioral health benefits, while offering a choice of general health plans to the enrolled population.

Behavioral managed care has led to substantial reductions on spending for the combination of mental and general health care. In the absence of care management, most private insurers required much higher copayment rates and placed many more limitations on services for behavioral health than for general health care. Managed behavioral health plans have been able to constrain mental health spending while reducing copayment rates to parity with general health services.

The rise of behavioral managed care, however, also illustrates some of the problems that may occur in an environment where a plan is paid a fixed amount to care for an enrolled population. Capitated plans have an incentive to shift costs to other providers. In the case of behavioral managed care, plans are responsible for providing behavioral health services, but do not pay for any prescribed medications or for behavioral health-care services delivered through general health plans. This bifurcation of responsibility encourages behavioral health plans to promote the use of medication, rather than psychotherapeutic, management of behavioral health conditions. This cost-shift dampens (although it does not eliminate) the effect of managed behavioral health organizations on overall health-care spending. It also encourages general health plans to limit the provision of behavioral health services in general health care.

Pharmacy benefits management is a second common type of specialized managed care. General health plans and purchasers (including the U.S. Medicare program) contract with pharmacy benefits management firms to control the costs of prescription pharmaceuticals covered under insurance. Pharmacy benefits managers develop formulary lists, negotiate prices with drug companies, provide incentives to patients to choose less costly drugs (such as formularies with copayment rates that vary by drug cost category), monitor drug use directly, and work to educate physicians about the benefits of generic drug use (‘counter-detailing’). Whereas pharmacy benefits management appears to lower the cost of drugs, some advocates have expressed concern that they limit access to necessary medications. Just recently, pharmaceutical benefit companies have expanded their scope of services to include disease management and other less drug-related and more health management–related services.

History Of Managed Care

Managed care has a long history. The earliest mention of arrangements in which individuals (often employers) contracted with a number of physicians to provide services for a preset fee to a defined population dates back to 1849. The Kaiser Health plan, and other large prepaid group practices, emerged in the 1930s. For many years, the plans faced considerable opposition from organized medicine.

The United States

The federal government became interested in managed care in the late 1960s and, in 1973, the U.S. government passed the HMO Act, which provided incentives for HMO growth. Between 1970 and 1975, the number of HMOs increased from 37 to 183 and HMO membership doubled, though from a very low base.

In 1982, California relaxed laws that limited the ability of health plans to selectively contract with a subset of providers. This led to the emergence of PPOs and between 1981 and 1984, 15 other states passed laws encouraging the growth of PPOs. Almost immediately, growth in PPO plans escalated rapidly. By the late 1990s, about 85% of those receiving employment-based health insurance benefits were enrolled in managed care. Most were enrolled in PPOs and similar open-access plans, not in traditional HMOs with highly restrictive provider access. In 2005, a total of about 68 million Americans were enrolled in HMOs and 108 million were enrolled in PPO-type products.

Managed care has also grown in the U.S. public sector.

Medicare permitted enrollment in HMOs from its inception, but plans had few incentives to participate. In 1983, only 1.5% of Medicare beneficiaries belonged to HMOs. From 1982 on, changes in Medicare legislation made managed care participation somewhat more attractive to Medicare beneficiaries, so that by 1990, 5.4% of Medicare beneficiaries belonged to HMOs. Further legislative action, and rising premiums for supplementary insurance, made managed care a more attractive option for Medicare beneficiaries during the 1990s. By 1996, one in eight Medicare beneficiaries belonged to a managed care plan. In 2005, 14% of Medicare enrollees belonged to HMOs.

Under Medicaid, a joint state-federal program, states have always been permitted to contract with managed care plans that could provide services to those who voluntarily enrolled. These voluntary plans attracted very few beneficiaries (only 1.3% of all beneficiaries in 1980) both because of difficulties in administering the plans and because Medicaid fee-for-service beneficiaries already received comprehensive services and had little cost sharing. Legislation in 1981 created the possibility of waivers for mandatory HMO enrollment. By 1991, nearly 10% of Medicaid beneficiaries were enrolled in managed care plans. Since then, states have been increasingly turning to managed care. By 1996, all states except Utah and Alaska used managed care as a component of their Medicaid programs, and nearly 40% of Medicaid beneficiaries were enrolled in managed care. The 1997

Balanced Budget Act eliminated the requirement that states seek a federal waiver to begin mandatory Medicaid managed care programs. While HMOs dominate the Medicaid managed care business, other forms of managed care are also in use. For example, California implemented a system of selective contracting for its Medicaid fee-for service program in 1982.

The rapid growth of managed care, its effects on provider incomes and on the practice of medicine, and the restrictions placed on enrollees eventually generated a legal backlash against managed care. In 1995, 27 states required state-regulated insurers to permit ‘any willing provider’ to participate in a health plan, and some states require managed care plans to permit those holding coverage a free choice of provider or mandate that plans must offer a point-of-service option. Overall, by 1996, nearly one-third of the states had strong or medium-strong restrictions on the operations of state-regulated managed care plans. States are continuing to pass laws through the 2000s. Since 2000, legal restrictions on selective contracting, consumer interest in looser forms of care management, and legislation promoting the use of high deductible plans as a response to rising health-care costs have all contributed to a flattening in the growth of managed care in the United States.

Changes in the market have also generated new organizational strategies for managed care plans. Today, vertically integrated plans are rare. Rather, under emerging models, health plans, medical groups, and hospital systems focus on those services they perform best while coordinating with other services primarily through contractual (rather than ownership) relationships. The consumer role has also changed, with a growing emphasis on consumer cost-sharing as a means of limiting the demand for services.

Europe

While managed care has a long history in the United States its implementation in other – mostly European – countries is rather recent. Initial European interest in managed care in the early 1990s focused on the introduction of managed care tools into frameworks of state-led medicine. Subsequent health-care reforms in the majority of European countries have paved the way for the development of new strategies and tools for managing healthcare systems. Nonetheless, the formation of managed care organizations such as HMOs themselves is still in its infancy (except in Switzerland). In other countries, managed care organizations exist primarily as pilot projects.

In France, a health-care reform in 1996 introduced computerized medical records, practice guidelines, and incentives to encourage the use of primary care practitioners as gatekeepers. These developments enhanced managed care goals of price competition and selective contracting, but at the same time encountered the resistance of practicing physicians. To date, gatekeeping has not been used to constrain service use.

In Germany, health reforms that incorporate managed care elements date back to 1993, but only recently (2004) has legislation enabled organizations to form integrated delivery systems. Since 2000, physician networks, hospitals, and other licensed health-care providers have been formally permitted to cooperate to achieve ‘integrated health-care delivery.’ The legislation also permitted the introduction of a primary care physician gatekeeper system and the possibility that an integrated delivery system would take on budget responsibility.

Despite this enabling legislation, regulatory restrictions made it difficult to take any of the authorized steps. The 2004 Health Care Modernization Act has now removed these regulatory obstacles and has provided start-up funding for the development of managed care organizations. As of June 30, 2006, there were 2590 contracts in Germany for integrated health-care delivery approaches, covering 3.7 million insured persons. Most of these contracts, however, are quite narrow and cover only specific diseases, rather than taking on financial responsibility for care of a defined population.

The United Kingdom’s National Health Service (NHS) has also incorporated several elements of managed care within its state-financed health-care system. The NHS has implemented incentives that make a substantial share of physician income dependent on performance. Since 2003, integrated care approaches have been initiated in three regions (Torbay, Northumbria, and Eastern Birmingham).

Switzerland leads Europe in the development of managed care, subsequent to its 1996 health-care reform. Today, there are 19 HMOs (about 100 000 members) and several IPA-like physician networks (about 390 000 members) in existence. Similarly to the development in the United States, the emergence of managed care in Switzerland enhanced the demand for quality measurement and monitoring.

Latin America And The Developing World

Managed care and managed care tools have also made inroads in the health systems of middle-income and developing countries. In developing countries with an emerging middle class, managed care plans operating integrated delivery systems offer a private alternative to often limited government-funded health-care systems. Large employers may contract with these plans to provide employee benefits.

In Chile, Argentina, Brazil, and several other Latin American countries, managed care plans have been integrated more fully into the health system. Managed care plans may be offered by employers, selected by individuals, or may be an insurance option for beneficiaries of the national social security systems (usually limited to employed workers). Managed care is viewed as an attractive option by governments because it often brings an inflow of new investment funds to the health sector and allows the government to off-load the risk of health expenses to independent entities.

Effects Of Managed Care

There has been a very substantial amount of research concerning the impact of managed care and of managed care tools. Despite this large volume of research, it is hard to come to definite conclusions about these effects. First, as discussed above, the term managed care incorporates many different combinations of mechanisms. Second, in most situations, managed care plans enroll different – often healthier – enrollees than do conventional plans. If managed care enrollees differ from enrollees of conventional insurance plans, differences in observed use at a point in time, growth in use over time, and outcomes may be a consequence of the underlying characteristics of the enrolled population, rather than anything the plans themselves do.

Third, managed care techniques control medical care costs, but, in many cases, they do so by adding administrative and managerial complexity, particularly in less integrated contexts. For example, implementing utilization review requires the insurer to hire skilled reviewers and forces physicians to communicate and often negotiate with these reviewers. These added administrative costs may reduce the overall social savings from the use of managed care tools.

Selection

Many studies in the United States have found differences in the characteristics of managed care and conventional insurance enrollees. On average, U.S. studies find that managed care plans in the private sector and in Medicare enroll beneficiaries who are 20% to 30% less costly than those who remain in conventional plans. In contrast, enrollees in German integrated delivery systems, which do not take financial responsibility for care but offer attractive care management programs for chronic populations, attract a population that is sicker than average.

Utilization

Many studies assess the effects of managed care on inpatient, outpatient, and total utilization. It is most valuable to study utilization across a broad range of services to address the possibility of cost shifting across services and from managed care entities to other providers. In early studies, managed care plans (generally staff and group model HMOs) reduced inpatient admission rates, had mixed effects on length of inpatient stays, and reduced total inpatient costs. The overall effect on inpatient days was a reduction of 5% to 25% for IPA plans and 35% for group and staff model plans. Similarly, analysis of integrated delivery models in the UK has found admission rates well below the national average.

The results of studies that compare PPOs with conventional plans are less clear. Some studies find that PPOs have lower costs, while others find that they have higher costs than competing arrangements.

By the late 1990s, even conventional fee-for-service plans adopted many aspects of managed care, including utilization review and price negotiation. In several studies conducted in the mid and late 1990s, there were no longer any differences between costs of inpatient (or outpatient) service use patterns in HMOs and traditional indemnity plans. Managed care plans, however, do tend to pay lower prices to providers than do conventional insurers.

Evaluations of physician networks in Switzerland that use the primary care physician as the gatekeeper also find that managed care models have lower costs than other plans. However, evidence varies as these networks are very heterogeneous (looser or closer networks with or without budget responsibility). Studies find risk-adjusted savings of 20% to 30% for HMOs and 7% to 20% for physician networks.

Quality

Most studies find few consistent differences between the quality of care provided in managed care plans and conventional insurance arrangements. To the extent that there is a pattern, managed care plans tend to perform better than conventional plans in the care of people with common chronic illnesses and worse in the care of those with serious, but less common, conditions. Subjective measures of quality, such as consumer satisfaction with care, tend to favor conventional insurance arrangements over managed care for most (but not all) populations.

Spillover Effects Of Managed Care

Managed care may also have effects – positive or negative – on the delivery of care to those who are not managed care beneficiaries. If plans attract healthier than average populations, they may drive up costs for nonmanaged care plans. Conversely, if a lower-cost managed care practice style diffuses to nonmanaged care physicians, the effects of managed care may be compounded. Early studies of the effects of managed care on total costs were generally case studies, and most found no effect. More recent studies focus on the rate of cost growth in areas with high managed care penetration. Most, but not all, of the more recent studies find that increases in managed care penetration are associated with reductions in the rate of growth of total costs. Whereas these studies mainly support the hypothesis that managed care can reduce total costs, they do not yet conclude the issue.

Managed Care And Public Health

The managed care model alters the orientation of traditional health insurance plans in a direction that is more compatible with public health. Unlike traditional private health insurance plans, which paid bills for services organized and managed by individual physicians, managed care plans can be held responsible for defined populations of patients. Moreover, the growth of managed care has prompted a new emphasis on the measurement of population-level health outcomes for covered populations. To the extent that health promotion, disease management, and management of environmental risks help managed care plans to achieve measurable outcomes, they have an enhanced incentive to incorporate these activities among their functions.

Managed care plans can effectively work as adjuncts to the screening and data collection efforts of health departments, for example, by screening populations for lead and reporting abnormal levels. Plans have also been involved in the design and implementation of immunization and disease registries. Highly integrated plans have also been able to use their population level data to conduct important public health research.

Despite the potential for managed care to complement public health activities, the level of interaction between managed care organizations and public health departments in the United States has been limited. In a recent survey, only about one-half of U.S. local health departments had interacted with local managed care plans at all. Interactions between public health departments and managed care plans have been primarily around public sector (especially Medicaid) managed care plans. The providers in these plans are often traditional public health safety net providers.

Managed care plans cannot take over all public health functions. These plans are typically at risk for only a segment of a community, whereas public health has responsibility for the health of the community as a whole. Managed care plans have little, if any, incentive to invest in activities that benefit populations who are not enrolled in their plans, although a few are engaged in community-level public health activities.

Managed care also poses some dangers for health departments. Managed care plans face incentives to offload some of their costs onto public health departments and other public providers. This type of cost shifting, from a risk-bearing managed care plan to public entities, such as public health services, has been documented in the literature on managed behavioral health care. The growth of managed care – and the array of preventive activities that plans provide – may also reduce the funding base of traditional public health departments, making it more difficult for them to meet their community-level mandate.

Conclusion

Despite the recent backlash, managed care and managed care tools, are likely to remain an important part of the U.S. health-care system and a growing component of healthcare systems in other countries. Managed care could also contribute to the public health orientation of social health insurance systems. The tools of managed care, including the use of selective contracting and incentive payments, have applicability in both private and public health-care delivery. Just as managed care has built on public health approaches, public health may be able to adopt managed care strategies as it aims to provide more services with ever-tightening budgets.

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