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HMORN ABSTRACTS

HMORN Abstracts

 We examined consumers' search for informationabout health insurance choices and their use of the Internet for thatsearch and to manage health benefits.

 We surveyed a random sample of more than4500 individuals aged 21 years and older who were members of asurvey research panel during December 2001 and January 2002.

 The survey included questions about searching forhealth insurance information in 3 health insurance markets:Medicare, individual or nongroup, and employer-sponsored group.We also asked questions about use of the Internet to manage healthbenefits. We tabulated means of responses to each question bymarket and tested for independence across demographic groupsusing the Pearson chi-square test.

 We identified important differences across and withinmarkets in the extent to which people look for information abouthealth insurance alternatives and the role of the Internet in theirsearch. Although many individuals were unaware of whether theiremployer or health plan provided a website to manage health benefits,those who used the sites generally evaluated them favorably.

 Our results suggest that the Internet is an importantsource of health insurance information, particularly for individualspurchasing coverage individually in the nongroup andMedicare markets relative to those obtaining coverage from anemployer. In the case of Medicare coverage, studies focusing onbeneficiaries' use of Internet resources may underestimate theInternet's importance by neglecting caregivers who use theInternet. Many individuals may be unaware of the valuableresources available through employers or health plans.

Although estimates of the extent to which consumersturn to the Internet to obtain informationabout health and healthcare varyconsiderably, even low-end estimates suggest that theInternet is an important source of consumer healthinformation.

 To date, however, analyses of Internetapplications for consumer health has focused on theextent to which people use the Internet for informationabout health and healthcare. The role of the Internet inthe relationship between consumers and health planshas received considerably less attention. Nevertheless,the potential impact of Internet applications in this areais large. Health insurance is a complex and information-intensiveproduct, requiring extensive coordinationamong consumers, patients, insurers, and providers. Intheory, consumers, purchasers, and health plans couldbenefit substantially from technological innovation thateither improved the ability of consumers to obtaininformation about the types of health insurance availableto them or reduced the cost or increased the qualityof health insurance products.

Many examples of these types of Internet-based innovationsalready exist. For Medicare beneficiaries, privatebrokerage sites focus primarily on individual supplemental"Medigap" coverage. Public and private not-for-profitorganizations have developed sites intended to presentcomprehensive information about the full range of choicesavailable to Medicare beneficiaries (eg, http://www.medicare.gov and http://www.calmedicare.gov) in responseto the increasing complexity of the choices availableto Medicare beneficiaries combined with evidence ofa lack of understanding among these individuals of theirchoices.

 Internet-based brokerage sites serve the individualand small group markets, potentially reducing thehigh loading costs and consumer search costs traditionallyconsidered major drawbacks of this market.

 Thesesites frequently provide information about the healthinsurance options and premiums available to an individual,often customized to his or her personal characteristicssuch as age, sex, health status, and geographiclocation. In the employment-based market, both employersand private not-for-profit organizations offer healthplan comparison information over the Internet. Privatenot-for-profit organizations also offer information aboutthe quality and coverage of health plans either in specificmarkets or nationwide (eg, Healthscope by the PacificBusiness Group on Health and the National Commissionfor Quality Assurance).

The Internet may also reduce the costs of offering andmanaging health benefits. Employers can provide theirown Web site, with a range of functionality, or can outsourcebenefits administration to online companies thathandle many of the administrative functions.

 Moresophisticated employer sites offer dynamic functionssuch as online enrollment and claims processing. A 1999survey of employers found that one third of employerswith 500 or more employees and two thirds of employerswith 20 000 or more employees used an Internet orintranet to manage health benefits, although interactiveapplications, such as online enrollment, were less common.

 Similar products are available directly fromhealth insurers and health plans, offering features suchas provider network and drug formulary searches, informationabout coverage, health information, and prescriptiondrug refills.

In this study, we examined the extent to which consumerssearch for information about health insuranceand the role of the Internet in their search. We alsoexamined the extent to which individuals use theInternet to manage health benefits. Despite the emergenceof new technologies in this area, virtually noempirical evidence exists on the extent to which thesetechnologies are used by consumers. Studies of theMedicare market have focused on the extent to whichMedicare beneficiaries use the Internet resources availablefrom the Centers for Medicaid and MedicareServices (CMS). Approximately 3% of beneficiaries usedthe CMS site in February 2001, although a survey of siteusers indicated that families and friends of beneficiariesas well as healthcare professionals represent a large proportionof the users of the site.

We surveyed a random sample of adults in the UnitedStates on their search for information about healthinsurance and their use of the Internet for healthinsurance applications. We drew our sample from anInternet-enabled research panel of more than 60 000households developed and maintained by KnowledgeNetworks, a survey research firm. Panel members wererandomly selected to receive free Internet accessthrough MSN WebTV in exchange for periodically participatingin short surveys. At the time of our survey,the panel acceptance rate was 41%, and the panel attritionrate was 14%.

From the Knowledge Networks panel, we randomlyselected 6601 individuals 21 years of age and older toreceive our survey, including 3967 individuals from thegeneral population and an oversample of 2634 individuals50 years and older. The survey was fielded betweenDecember 1, 2001, and January 21, 2002. The totalresponse rate was 68.3%, with a higher rate among theelderly (73.2%) than the general population (65.1%).Item nonresponse rates for individual questions used inthis analysis varied by question, but were very low,ranging from 0% to 8%.

We performed extensive analyses of the extent towhich our sample was nationally representative andfound that estimates of population demographics, theprevalence of health conditions, and provider utilizationfrom our data were consistent with those from otherhigh-quality population-based surveys.

 Nonetheless, thepossibility remains that persons who chose to participatein the panel differed from those who declined based ontheir interest in or ability to use the Internet. In previousstudies, we restricted our analysis to the subset of surveyrespondents indicating they had Internet access prior tojoining the panel to ensure that our estimates were representativeof Internet users in the United States.

 In thisstudy we did not make this restriction for 2 reasons. First,our study provides estimates of the extent to which individualslook for health information from any source.Restricting the sample to Internet users would havebiased this estimate. Second, this strategy allowed us toinclude subpopulations that traditionally are less likely tohave Internet access on their own, such as individualswith low income or levels of formal education, becauseeveryone on the panel had at least a minimum level ofInternet access provided by Knowledge Networksthrough WebTV. (Although some survey respondentsmay have been limited to MSN WebTV as their onlysource of Internet access, others had access through acomputer.) Fifty-three percent of the study sample hadInternet access prior to joining the panel.

Our survey questions addressed 2 study domains:searching for health insurance information and managinghealth benefits; and 3 health insurance markets:Medicare, nongroup, and employer-sponsored. We alsoasked respondents detailed information about theirhealth insurance status, which we used to identifyappropriate subsamples for particular analyses.

For the Medicare market, we asked all survey respondents,regardless of age or health insurance status,about their search for information. Our hypothesis wasthat many beneficiaries looking for information turn toyounger relatives or friends, who are likely to use theInternet in their search. For the nongroup market, weasked questions about searching for information toeveryone younger than 65 years (n = 3303), to capturesearches for either oneself or someone else. We hypothesized, however, that those without either employer-sponsoredor public coverage would be more likely to belooking for information on coverage through the nongroupmarket. The study sample for the employer-sponsoredmarket was defined as individuals indicatingthat they had a choice among employer-sponsoredplans, either through their own employer or someoneelse's (n = 1410).

We asked each eligible respondent whether he or shesearched for information in the past year, customizingthe questions by market. For the Medicare market,respondents were asked about their search for Medicaremanaged care plans or Medigap insurance. For the nongroupmarket, respondents were asked about "healthinsurance they could purchase themselves, not throughan employer or union." For the employer-sponsoredmarket, respondents were asked about health insuranceplans offered to them through an employer or union. Weasked individuals responding positively if they used theInternet in their search. To respondents indicating theyused the Internet, we asked whether they stronglyagreed, agreed, disagreed, or strongly disagreed with 5statements evaluating their search, ranging fromwhether they were able to find the information theywere seeking to whether the information influenced adecision about health insurance. Again, the questionswere customized by market and the exact wording ispresented in each table.

When asking about managing health benefits, we surveyedonly respondents younger than 65 years with privatecoverage, either employer-sponsored or nongroup.We asked those with employer-sponsored coverage (n =2338) questions about their employer's health benefitsWeb site and those with either employer-sponsored ornongroup coverage (n = 2472) questions about theirplan's Web site. The question format was similar acrosssamples, but the wording was customized to employeror health plan. We first asked respondents if theiremployer or health plan offered a Web site. For respondentsindicating yes, we asked them if they had visitedthat Web site. For those indicating they had visited theWeb site, we asked 3 questions that were intended todifferentiate among broad categories of functionality.Once again, the exact wording of the questions is presentedin the relevant tables.

We calculated means of responses to each questionoverall and, in some cases, by insurance coverage usingpoststratification weights to adjust for oversampling andsurvey nonresponse. The weighting corrected the distributionof respondents to match the known distributionof the US population based on age, sex, race, education,region, metropolitan residence, and veteran status,using the Current Population Survey as the standard.(Standard errors in the regressions were not adjustedfor the complex survey design. Many of our analyseswere based on relatively small subsamples of the surveypopulation, resulting in primary sampling units withvery small numbers of respondents, in many cases 1.When possible, we adjusted the standard errors fordesign effects and found that it had virtually no effect onthe statistical significance of our results.) We tested forindependence across groups using the Pearson chi-squaretest.

 presents the distribution of our sample bysex, self-reported health status, education, income, andage.

Consumer Search for Information AboutHealth Insurance

 Overall, 6.7% of the study populationsaid they had looked for information about Medicaremanaged care or Medigap coverage during the past year(

). Among those looking for information, 18% usedthe Internet. The rate of information seeking aboutMedicare coverage was relatively low among youngerindividuals, just 4.4% and 3.6% for individuals youngerthan 40 years and 40 to 59 years, respectively. Not surprisingly,the rate of information seeking peaked at 64 to66 years (28%), the time period during which most individualsbecome eligible for Medicare coverage. Informationseeking declined among older adults (15.4%).

Although persons 64 years and older were morelikely than younger individuals to look for informationabout Medicare alternatives, younger individuals weremore likely to use the Internet for their search(Figure). Five percent of individuals 67 years and olderused the Internet compared with 33% of those youngerthan 40 years. Individuals younger than 64 years representedmore than half of those seeking informationabout Medicare and more than 80% of those who usedthe Internet (results not shown), providing support forour hypothesis that younger adults are an importantaudience for information about Medicare coverage.

Source of insurance coverage was associated withinformation seeking among the elderly population, withMedicare managed care enrollees (34%) and Medicarebeneficiaries with Medigap coverage (26%) most likely toreport looking for information. Seventeen percent ofMedicare beneficiaries with supplemental coverage froman employer reported looking for information on supplementalcoverage or Medicare managed care plans.Beneficiaries with employer-sponsored supplementalcoverage were the most likely to usethe Internet in their search. This findingmay be because of either greaterfamiliarity among these individualswith the Internet or an important roleof employers in providing or directingretirees to Internet-based resources.Twenty-seven percent of elderly Medicarebeneficiaries indicated "othersource of supplemental coverage" orthat they did not know what type ofsupplemental coverage they had, indicatingsome difficulty among this populationin responding to questions aboutthe source of their insurance coverage.Thus, our results by insurance statusmay reflect a subset of beneficiarieswith greater knowledge about issues ofinsurance coverage in general.

 Sixteen percentof people younger than 65 yearsreported looking for information aboutcoverage in the nongroup market, and 27% of these peoplesearched the Internet (

). As hypothesized,people with nongroup coverage and the uninsured weremore likely to look for information about coverage inthe nongroup market than those with employer-sponsoredor public insurance, although they were less likelythan those with employer-sponsored coverage tosearch the Internet. Thirty-seven percent and 32% ofindividuals who reported no insurance or coverage purchasedin the nongroup market, respectively, reportedsearching for information about coverage in the nongroupmarket.

 Although many peoplewith a choice among employer-sponsored plans lookedfor information before enrolling (67%), relatively fewsearched the Internet (16%) (Table 2).

Evaluation of Information Foundon the Internet

Overall, respondents favorably evaluated the informationthey found on the Internet by indicating thatthey either agreed or strongly agreed with 5 statementspositively evaluating their search. However, we notedimportant differences in the evaluations across the markets(

). In the employer and nongroup markets,fewer respondents reported agreeing or strongly agreeingwith each statement as the items identified increasinglysubstantive effects. Respondents who searched theInternet for information about nongroup coverage wereless likely than those in the employer-sponsored marketto agree or strongly agree with each of the statements.Among people searching the Internet in the nongroupmarket, 75% indicated they were able to find the informationthey were looking for, whereas 58% reportedthat the information they found influenced a choiceabout health insurance. In the employer-sponsoredmarket, in contrast, 92% were able to find the informationthey were looking for, whereas 79% reported thatthe information they found influenced a decision abouthealth insurance. In the Medicare market, in contrast,people more frequently reported difficulty locating theinformation they were looking for, but favorably evaluatedthe information they found. Twenty-two percentdisagreed or strongly disagreed with the statementthat they were able to find the information they werelooking for. More than 90%, however, indicated thatthey were able to understand the information theyfound, that they learned something new from theinformation they found, and that the informationimproved their understanding of the insurance choicesavailable to them. Sixty-seven percent reportedthat the information they found influenced a choiceabout health insurance. Because this sample includedboth elderly and nonelderly individuals who usedthe Internet for the Medicare market, these resultscannot be generalized to Medicare beneficiaries.

Many people with private health insurance wereunaware of whether their employer or health planoffered a Web site related to their coverage. Almost half(49%) of individuals with employer-sponsored coveragedid not know if their employer offered a related Website, and nearly two thirds (64%) of those with any privatecoverage did not know if their plan had a Web site(

). Statistical significance in this table refersto tests of independence across groups. Awareness ofemployer Web sites was similar between people with achoice of plans and those with no choice. However,individuals with a choice of plans were more likely toreport that their employer did offer a Web site. In thecase of health plan Web sites, people with a choice ofplans were more likely than those with no choice to beaware of whether the health plan offered a site. Awarenessof health plan sites was extremely low among thosewith nongroup coverage (71% did not know whethertheir health plan offered a site).

Relatively few people reported visiting their employer'sor health plan's Web site. Among people indicatingtheir employer or plan had a Web site, 29% and 33%reported visiting the Web site, respectively (Table 4).Individuals with a choice among employer-sponsoredplans were more likely to visit their employer's Web site.

Individuals who visited an employer or plan Web sitegenerally evaluated their functionality favorably,although the sites more often contained coverage andhealth information than tools for managing health benefits.Eighty-eight percent of individuals who visited theiremployer's site indicated that it provided informationthat helped them understand their coverage, whereasonly 70% indicated that they used their employer's Website to manage their health benefits (

). Theresults were similar for plan sites. When assessingemployer Web sites, individuals with a choice amongplans were more likely than those with no choice to indicatethat the site provided information that helped themunderstand their coverage (91% compared with 74%) butequally likely to indicate that the site allowed them tomanage their health benefits (71% compared with 67%).

Our study identified important differences both acrossand within markets in the extent to which people look forinformation about health insurance and the role of theInternet in their search. We found that the nonelderlycomprised a large proportion of the population seekinginformation about Medicare and its alternatives, suggestingthat family and friends, many of whom assume caregivingduties, play an important role in findinginformation and assisting older individuals with their coverage choices. This finding is consistent with qualitativeresearch indicating that caregivers play an importantrole in assisting the elderly in health insurance decisionmaking.

 Currently, these younger information seekersare more likely to search the Internet, implying that themost frequent users of Web sites targeted to Medicarebeneficiaries are nonelderly. Although we found littleevidence of difficulty in understanding or using the information,we were unable to determine whether these generalfindings for Medicare coverage were true for bothyounger and older populations due to small sample sizes.Nevertheless, our results indicate that the nonelderlypopulation is an important target for information aboutMedicare coverage and its alternatives, both on and offthe Internet. Although further research to identify thebarriers the elderly face in using the Internet to obtainthis type of information would be helpful, these barriersare likely to diminish over time as Internet usage for alltypes of applications continues to increase among thispopulation and the aging of younger cohorts creates anelderly population with greater experience with thesetechnologies.

Our results also suggested that employers play animportant role in identifying valuable information andmaking it accessible to workers and retirees. Amongindividuals aged 65 years and older, the most frequentusers of the Internet for health insurance choices werethose with employer-sponsored retiree benefits. Theemployer's role in the provision of health benefits thereforeappears to facilitate the use of the Internet as aninformation source for older Americans. More generally,individuals searching the Internet for information in theemployer-sponsored market evaluated the informationthey found more favorably than those searching forinformation in the nongroup and Medicare markets.

We found that many people with a choice amongemployer-sponsored plans looked for information beforeenrolling, but most used "traditional" sources and relativelyfew used the Internet. This finding may be becauseemployers offered both online and offline resources forworkers. Greater efforts by employers to direct individualsto information resources available on the Internet aswell as greater promotion of publicly available resourcesmay help individuals make these choices.

We found evidence that many people look for informationabout coverage in the nongroup market, particularlyindividuals without employer-sponsored orpublic coverage. Although many of these people turn tothe Internet, the information available there appears tobe less useful than that available for other types of coverage.Although it is difficult to determine whether thisis due to the quality of the information available or thequality of the choices available, this finding suggeststhat further study of the experiences of individualsshopping for coverage in the nongroup market, particularlytheir use of the Internet, may generate a betterunderstanding of the barriers to obtaining health insurancein the United States.

Finally, our results suggested that many people maynot be aware of potentially valuable resources availablethrough their employer or health plan to help themunderstand their coverage, manage their health benefits,or find health and healthcare information. Althoughawareness of these Web sites is low, site visitors tend toevaluate them favorably, perhaps because people aremore likely to be aware of good Web sites. Although wefound that plan and employer Web sites were equallyvaluable, this result could have been because of the difficultysome individuals may face in identifying theoperator of a particular site. For example, manyemployers may offer sites that enable covered workersto click through to the plan Web site.

Our survey was administered to individuals randomlychosen to receive Internet access in exchange for participatingin a survey research panel. Whereas somesurvey respondents had Internet access prior to joiningthe panel, others did not. In other work, we found thatthe use of the Internet for health applications by surveyrespondents who had Internet access prior to joiningthe panel was similar to estimates from nationally representativesurveys

 and those who gained Internetaccess by joining the panel generally had lower rates ofuse of the Internet for health applications.

 This observationsuggests caution in interpreting our estimates asrepresenting the prevalence of national Internet use forthese types of applications. If our sample introducedany bias relative to a nationally representative sample,we likely would have overestimated the extent to whichindividuals used the Internet for health insurance orunderestimated the prevalence of use among the populationwho obtained Internet access on their own.

From the Department of Health Research and Policy, Stanford University School ofMedicine, Stanford, Calif (MKB, THW, LB); the Center for Health Policy, StanfordUniversity, Stanford, Calif (SJS); and the VA Palo Alto Health Care System, Palo Alto, Calif(THW).

Funding for this research was provided by the Department of Veterans Affairs, StanfordUniversity Office of Technology and Licensing, and the National Institute on Aging, Grant#AG17253. Dr Bundorf was also supported by grant KO2-HS11668-01 from the Agency forHealthcare Research and Quality.

A preliminary version of this report was presented at the 2002 Academy HealthConference.

Address correspondence to: M. Kate Bundorf, PhD, Department of Health Researchand Policy, Stanford University School of Medicine, HRP Redwood Building, Room 257,Stanford, CA 94205-5405. E-mail: 

1. Baker L, Wagner TH, Singer S, Bundorf MK.

 Use of the Internet and e-mail forhealth care information: results from a national survey [published correctionappears in 

The Online Health Care Revolution: How theWeb Helps Americans Take Better Care of Themselves

. Washington, DC: PewInternet and American Life Project; 2000. 

E-HEALTH

Consumers' Use of the Internet for Health Insurance

Science is the basis of medicine. Good science leads to better decisions and more effective systems to support those decisions. Most individuals associate science primarily with academic institutions. However, top-quality research relevant to managing the health of populations and the care of specific clinical conditions is increasingly being carried out by investigators working in integrated healthcare systems. This introduction outlines the activities of the HMO Research Network, whose researchers have made and continue to make important contributions to the field of health research. Its objective is to inform readers of the activities and value of systems-based health research. We describe the importance and extent of the research conducted by HMO Research Network members, as well as the advantages of conducting research in such settings.

Integrated care health maintenance organizations (HMOs) provide an ideal mix of population base, electronic medical and financial databases, and longitudinal observation for much health research. They are especially well situated for research addressing issues such as the costs and effectiveness of prevention and treatment practices, organization of care, secular trends in diseases, and relative priorities on how to apportion scarce resources. The HMO Research Network (HMORN) is carrying out research that is crucial to improving the quality, availability, and effectiveness of healthcare. The 13 HMORN research centers perform 90% of all research conducted by HMOs with formal research centers.

The first integrated care system research center was founded in 1961, and the advantages of conducting research in such environments led to the formation of additional centers. In 1994, these centers established a professional organization, the HMORN, to encourage high-quality, public domain research within HMOs. The 13 geographically dispersed HMORN centers represent integrated care systems with approximately 13 million members. Collectively, they study a broad range of health issues. Research conducted by member organizations is in the public domain, and results of their studies are published in approximately 1200 peer-reviewed publications annually.

Members of the HMORN include several exclusively prepaid group practices, several mixed-model HMOs, and 1 independent practice association HMO. These centers vary in structure and organization, as do their parent health plans. However, they have common access to a defined population of members and data regarding these members, much of it electronically available, which permits longitudinal evaluation of health practices. Their placement within large health systems makes rigorous evaluation of alternative approaches to care feasible. The members of the HMORN have electronic medical records systems or are in the process of installing them. As they come online, these systems will provide unprecedented opportunities to evaluate alternative approaches to treatment, longterm outcomes of care, cost-effectiveness and cost-benefits, rare disease epidemiology and treatment, and many other critical healthcare issues.

 lists the members of the HMORN and selected characteristics of their research centers. Each center is funded primarily through competitive grants and contracts from federal, foundation, and proprietary funding organizations. The annual HMORN scientific meeting combines presentations of scientific papers with seminars on how to develop collaborative research studies that permit the member organizations to address research questions that cannot be carried out within single healthcare organizations.

Research from the HMORN centers has affected the organization, quality of care, federal and state health policies and regulations, plan benefits, and many other aspects of healthcare delivery. The studies summarized in 

 are some examples of HMORN projects that have influenced healthcare, health law, and health policy. At any given point in time, the members of the HMORN are conducting more than 2000 research studies.

The HMORN research centers have also been key participants in some of the nation's most important multisite National Institutes of Health studies, including the Multiple Risk Factor Intervention Trial,

 Systolic Hypertension in the Elderly Program,

 Dietary Approaches to Stop Hypertension,

 and others. The HMORN participates in 5 federally funded, national, multisite research networks (

): Cancer Research Network, Center for Education and Research in Therapeutics, Cancer Care Outcomes Research and Surveillance, Integrated Delivery System Research Network, and Vaccine Safety Datalink. The HMORN also has formal partnerships with the American Association of Health Plans and the Alliance of Community Health Plans for the conduct of public health research.

BENEFITS OF RESEARCH IN INTEGRATED CARE SYSTEMS

Integrated care research has unique access to entire populations, comprehensive data systems, and realworld delivery issues.

 Defined populations of plan members permit long-term observation, with numerators (the sick) and denominators (the population). This permits the estimation of rates that are essential to understanding changes over time, cause-and-effect relationships, and factors associated with disease incidence and treatment outcome.

 In integrated care systems, many cohorts exist naturally, and data on those cohorts are present in electronic form. This permits long-term cohort studies to be conducted retrospectively and at reasonable cost. The experiences of health plan members can identify secular trends, outcomes of system interventions, and risk factors and their interactions.

 Health plan members are more likely to respond to an appeal for research volunteers when that appeal is from their own health plan. Recruitment and retention rates from integrated care system research cohorts are substantially higher than those from community recruitment and, therefore, afford high external validity. 

 Large, often nonprofit, integrated care systems are usually demographically representative of their geographic populations, enabling findings that are generalizable to other defined populations.

 The members of the HMORN are diverse ethnically, culturally, and geographically, facilitating studies that address racial and other disparities and are generalizable to other populations.

 Integrated care systems maintain medical records that may include information across inpatient and outpatient settings and different clinical providers, thus enabling comprehensive pictures of a population's health and healthcare use.

Electronic Data Facilitating Preliminary and Rare Disease Studies.

 Successful research requires preliminary data, often collected at considerable expense, time, and energy. Comprehensive data information systems in integrated care can serve much of this need. Many research ideas can be developed without pilot funds beyond those required for retrieving and analyzing data from existing databases.

Electronic data permit identification of less common diseases and treatments. Accessing 5 of 11 Cancer Research Network sites identified 132 580 cancer cases for one study,

 including 2680 pancreatic cancers, 2788 ovarian cancers, 2986 bladder cancers, and 5147 non-Hodgkin lymphomas.

 Perhaps the greatest innovation in medical care in the 21st century will grow out of the shift to electronic medical records. Electronic medical records systems have the capacity to facilitate use of consensus guidelines, minimize drug interactions and reactions, design prevention and care plans that are individually tailored, and provide extraordinary epidemiologic opportunities to observe disease trends, disease outcomes, and disease or risk factor associations. They will provide health economists the opportunity to study the relative costs and effectiveness of different approaches to care and will assist in designing and evaluating alternative structures for delivering care.

Ability To Test Efficacy of Care Alternatives.

 Large integrated delivery systems often experiment with innovations in delivery. These innovations can be rigorously evaluated when trained researchers are involved.

 The presence of the HMORN centers within healthcare systems encourages interactions and critical partnerships among researchers, clinicians, and managers early in the research process. This promotes implementation and testing in real-world settings. The perspectives of managers, clinicians, and staff often lead researchers to modify initial assumptions about what will or will not work within their systems, nurturing the development of functional innovations that can be successfully translated into practice. Facilitating research serves the clinicians, the patients, and, ultimately, the entire system. These partnerships create an environment that translates research findings into practice.

The US healthcare system faces serious challenges in the years ahead.

 Meeting clinical and economic goals is difficult because of complex reimbursement processes, perverse incentives that encourage excessive services, a preoccupation with expensive technologies, the inability to stop doing what does not work, a legal system that encourages faultfinding instead of remedial action, and the lack of a systematic means for learning from mistakes. Research within integrated care systems can develop new concepts and methods that define basic goals, produce practical tools that document the nature and magnitude of problems and outcomes, evaluate strategies and interventions for improving care, and assess new models, programs, and systems.

 These systems are also ideal venues for studies that examine the relative benefits and priorities for using healthcare resources.

In integrated care systems, key factors intersect. Economics pushes those systems to avoid unnecessary services; quality assurance processes such as the Healthplan Employer Data Information Set direct them toward quality improvement; and the clinical setting requires them to take into account the real-world realities of delivering care. These settings are ideal for testing and evaluating preventive and treatment services.

The HMORN recognizes that access to these extraordinary resources is a public trust. The HMORN vision is to "transform US health care through research on the diverse populations served by integrated health systems." It strives to achieve this goal through public domain research that serves the public interest. The work of the research centers of the HMORN supports good decision making by clinicians, managers, policy makers, and members of their respective health plans. Because integrated care systems are such an ideal setting in which to conduct many types of applied medical research, the larger integrated care delivery systems have a social obligation to support and participate in such research. High-quality medical care requires high-quality research and evaluation. Clinicians, managers, and the public must come to view research as an integral part of what health systems do. The design of data systems in large healthcare organizations needs to include considerations relating to research and evaluation. University researchers should develop closer partnerships with their health system research colleagues to improve the quality and quantity of research in these settings,

We thank the many persons who contributed information for inclusion in this article, including:

Jerry Gurwitz, MD, Diana Petitti, MD, Robert S. Zeiger, MD, Barbara Stoddart, MBA, Arne Beck, PhD, Paul Barrett, MD, Maggie Gunter, PhD, Eric Larson, MD, Andy Nelson, MPH, Kate Rardin, MPH, Barbara Olson Bullis, MA, Deborah Shatin, PhD, Mary Durham, PhD, Don Freel, MBA, Ryne Lee, MBA, Richard Platt, MD, MSc, and Ann Plasso, BA.

From the Center for Health Research, Kaiser Permanente, Hawaii, Honolulu (TMV); Henry Ford Health System, Detroit, Mich (JE-L); Kaiser Permanente, Atlanta, Georgia, (DT); and Group Health Cooperative, Seattle, Wash (SMG).

Address correspondence to: Thomas M. Vogt, MD, MPH, FAHA, Center for Health Research, Kaiser Permanente, Hawaii, 501 Alakawa Street, Suite 201, Honolulu, HI 96817. E-mail: 

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NEW AFFILIATIONS: PARTNERING WITH THE HMO RESEARCH NETWORK

The Role of Research in Integrated Healthcare Systems: The HMO Research Network

 To compare the cost effectiveness of prophylaxiswith a low-molecular-weight heparin with that of prophylaxis withunfractionated heparin for the prevention of venous thromboembolismin acutely ill medical inpatients.

 Cost-effectiveness analysis based on decision-treemodel.

  A hypothetical cohort of 10 000patients was assumed to receive either (1) prophylaxis with enoxaparin,a low-molecular-weight heparin, 40 mg daily; (2) prophylaxiswith unfractionated heparin, 5000 IU twice daily; or (3) noprophylaxis. We developed a decision-analytic model with parameterestimates derived from published clinical trials and other secondarysources. Then, for each strategy, we estimated the risks ofvenous thromboembolism, complications of prophylaxis and treatment(heparin-induced thrombocytopenia and bleeding), mortality,and costs of prophylaxis and treatment within a 30-day period.

 In a hypothetical cohort of 10 000 inpatients, expectednumbers of deaths attributable to venous thromboembolism ordrug complications related to both prophylaxis for and treatment ofVTE over a 30-day period were 37 with enoxaparin prophylaxis, 53with unfractionated heparin prophylaxis, and 81 with no prophylaxis.In 2001, corresponding expected costs of prevention, diagnosis,and management of VTE were $3 502 000 for enoxaparin,$3 772 000 for unfractionated heparin, and $3 105 000 for no prophylaxis.The incremental cost per death averted with enoxaparinprophylaxis versus no prophylaxis was $9100. Enoxaparin dominatedunfractionated heparin by being both more effective and lesscostly in the base-case analysis, as well as in sensitivity analyses inwhich equal efficacy and equal risks of bleeding were assumed.

 Thromboprophylaxis with this low-molecular-weightheparin represents a cost-effective use of healthcare resourcesin acutely ill medical inpatients and dominatesthromboprophylaxis with unfractionated heparin.

Venous thromboembolism (VTE) is a life-threateningvascular disease common among hospitalizedpatients. It is estimated that more than 170000 incident cases of VTE are diagnosed in hospitalizedpatients in the United States each year, and morethan 20 000 of these patients die of the condition beforedischarge.

  Because many cases of incident thromboembolismgo undetected and untreated, primary preventionin at-risk patients is of critical importance.

Several subgroups of hospitalized patients are at elevatedrisk for VTE, including those undergoing orthopedicor other major surgery, as well as those with acutecirculatory conditions such as myocardial infarction,atrial fibrillation, angina, or thrombotic stroke. TheSixth ACCP Guidelines for Antithrombotic Therapy forPrevention and Treatment of Thrombosis recommendthromboprophylaxis as standard practice for thesepatients.

 In recent years, the substantial risk of VTE inthe general medical population has emerged as animportant clinical concern also.

 Acutely ill medicalinpatients, such as those hospitalized for congestiveheart failure, chronic obstructive pulmonary disease, oracute infections, often have hypercoagulability andperiods of prolonged immobility that may place them atincreased risk of VTE.

 Because these patients are likelyto have one or more additional risk factors (eg, historyof VTE, advanced age, obesity, varicose veins,estrogen use),

 the potential benefits of thromboprophylaxisin this population may be substantial.

As the risk of VTE among general medical patientshas gained recognition, the introduction of low-molecular-weight heparin (LMWH) has provided an alternativeto thromboprophylaxis with unfractionated heparin(UFH), the previous standard. The efficacy of bothLMWH and UFH as thromboprophylaxis in selectedgroups of medical inpatients has been demonstrated inclinical trials,

 and there is evidence that LMWH mayhave a better safety profile than UFH with regard to bothhemorrhage

 and heparin-induced thrombocytopenia(HIT).

 Because LMWH is more costly, however,the question remains whether its use can be justified interms of reduced risk ofdrug-related adverseevents and, possibly,improved efficacy. Toaddress this question,we examined the costeffectiveness of prophylaxiswith an LMWH,specifically enoxaparin,versus prophylaxis withUFH in acutely ill generalmedical inpatients.

We used techniquesof decision analysis anddata from secondarysources to develop a model of the prevention, detection,treatment, and outcomes of VTE in generalmedical patients. A hypothetical cohort of 10 000acutely ill medical inpatients was assumed to receiveone of three methods of thromboprophylaxis:(1) enoxaparin, a representative LMWH (Lovenox;Aventis Pharmaceuticals; Bridgewater, NJ), 40 mgadministered subcutaneously once daily; (2) UFH,5000 IU administered subcutaneously twice daily; or(3) no prophylaxis. Our choice of dosing and frequencyof administration reflects current recommendationsfor thromboprophylaxis in medical patients.

 For eachstrategy, we estimated the 30-day risks of VTE,including deep vein thrombosis (DVT) and/or pulmonaryembolism (PE); complications of prophylaxisand therapy, such as HIT and bleeding; mortality; andthe costs of prophylaxis, diagnostic testing, and treatment.We used these estimates to examine the incrementalcost effectiveness of thromboprophylaxis,expressed in terms of the cost per death averted.

Treatment patterns and outcomes of care were modeledfor 30 days from the time of hospital admission.This time period was chosen to capture DVT and PEoccurring both in the hospital and during the periodimmediately following discharge, during which time patientsmay continue to be at elevated risk of VTE. Ouranalysis was conducted from the perspective of a thirdpartyhealth insurer and therefore considered only directmedical costs.

The structure of the decision-tree model is illustratedin 

. The clinical starting point forthe model is admission to an acute-care facility fortreatment of a serious medical condition. For thesepatients, the clinical decision of interest is the methodof thromboprophylaxis administered, either enoxaparin,UFH, or no prophylaxis (Figure 1). Patientsreceiving enoxaparin or UFH are assumed to be at riskfor drug-related adverse events, including hemorrhage("bleed") and HIT. Bleeds may be either minor or major,while HIT is classified as asymptomatic or symptomaticaccording to the presence or absences of overtclinical symptoms. Major bleeds and symptomaticHIT may lead to death, though for modeling conveniencewe assumed that patients who survive one of theseadverse events are not at risk of additional adverseevents or VTE.

Patients who do not experience HIT or hemorrhageare at risk of DVT (Figure 2). Because clinical diagnosisof DVT is imperfect, the tree reflects this uncertaintyby allowing patients to receive a true- orfalse-positive or negative clinical diagnosis. Patientswith a positive clinical diagnosis (whether true or false)are referred for duplex ultrasound and, if confirmed, fortreatment. Those with a negative clinical diagnosisreceive no confirmatory diagnostic procedures ortreatment. This model assumes that all patientswhose DVT diagnosis is confirmed by ultrasoundundergo anticoagulation therapy with enoxaparin;such patients are at risk for bleeds and HIT. Patients whosurvive treatment-related adverse events, such as bleedsor HIT, finish treatment and are not at risk of furtheradverse events or PE.

Patients who have DVT and do not experience anadverse event from its treatment are at risk for PE(Figure 3). Patients who experience PE and survive theperiod immediately after the acute event may be giveneither a true-positive or a false-negative clinical diagnosisof PE. Patients with apositive clinical diagnosis(whether true or false) arereferred for a confirmatoryventilation—perfusion (V/Q)scan or computed tomography(CT) scan and, if positive,for treatment of PE.Patients may die fromtreated 

 untreated PE orfrom other underlyingmedical conditions.

Model estimation involvesassigning probabilityestimates to each of themodel's chance nodes andcost estimates to each pathway.Base-case transitionprobabilities and datasources are summarized in

Risks of failure and theoccurrence of adverseevents for each prophylaxismethod were obtained from the published literature. Weused data from MEDENOX,

 a recent placebo-controlledclinical trial, in our model, evaluating 40 mgenoxaparin once daily as thromboprophylaxis in medicalpatients to estimate the risk of DVT with enoxaparinprophylaxis and the baseline risk of DVT amonguntreated patients. MEDENOX is the only publishedplacebo-controlled trial of an LMWH that enrolled generalmedical patients, administered a dose of enoxaparinconsistent with current recommendations,

 and diagnosedDVT using venography. We were unable to identifyany published studies that compared an LMWH toeither UFH or placebo and met these criteria. Therefore,to estimate the risk of prophylaxis failure among patientsreceiving UFH, we used the results of a recent meta-analysisof trials that compared LMWH to UFH in medicalpatients

 and applied the summary risk-ratio of 0.83 tothe risk of prophylaxis failure in the LMWH arm of theMEDENOX trial.

Because HIT and bleeds occurred infrequently in thepublished trials of thromboprophylaxis in medical inpatientsand because their detection does not depend onvenography, estimates of the rates of occurrence andseverity of these events were drawn from a wider rangeof clinical trials than those used for the efficacy estimates.

 Published estimates of "symptomatic" or"severe" HIT

 were assumed to include thrombocytopenialeading to thromboembolism. The other transitionprobabilities in the model are uniform across alltreatment arms, and most were estimated from the publishedliterature. The estimate of the probability of false-negativeclinical diagnosis of DVT was derived fromstudies examining the prevalence of DVT in asymptomaticpatients.

 For the base—case analysis, the riskof death due to the underlying medical condition wasassumed to be 10%, which is consistent with the rates ofdeath reported in published clinical trials focusing onacutely ill medical inpatients.

 Finally, because weassumed that one half of the patients with suspected PEwould undergo CT scans and one half V/Q scans, weused the average sensitivity and specificity of these 2diagnostic techniques in the model. Where multipledata sources were used, estimates were combinedacross studies by direct pooling.

The model's cost parameters include (1) study medicationsand ancillary resources, (2) laboratory procedures,(3) hospital inpatient days, (4) physician inpatientvisits, and (5) physician office/outpatient visits. All costestimates employed in the analysis are summarized in

Drug acquisition costs were estimated from averagewholesale prices

; for the weight-based doses, the totalamount of drug used was estimated assuming a 75-kgpatient. Cost estimates associated with the suppliesused to administer drugs were obtained from publisheddata.

 The costs of laboratory procedures for monitoringanticoagulation therapy were estimated using datafrom the Centers for Medicare & Medicaid Services

;and the costs of physician inpatient and office/outpatientvisits were estimated using the Medicare Resource-Based Relative Value Scale payment rates.

 Mean dailyinpatient costs attributable to adverse drug reactionsand VTE were estimated by dividing the unadjustedpayment for deep vein thrombophlebitis (DiagnosisRelated Group 128) by the average length of stay forthis diagnosis.

Although our primary focus was on costs incurredwithin 30 days of hospital admission, we included costsafter 30 days if they were incurred as a direct consequenceof events within the first 30 days (eg, 6 monthsof warfarin therapy following DVT). All costs weremeasured in 2001 US dollars; where necessary, costswere updated to 2001 using the medical-care componentof the Consumer Price Index.

 Because of the brieftime horizon of the model, discounting was notrequired.

For each of the 3 prophylaxis methods being evaluated,we used our model to estimate the total costs of prevention,detection, treatment, and outcomes of VTE in acohort of 10 000 acutely ill medical inpatients over a 30-day period. Cost effectiveness is expressed in terms ofthe cost per death averted. To compare treatment strategieswe first rank-ordered regimens by increasing costand eliminated those strategies that were found bothmore costly and less effective than (

 by) others.For each remaining strategy we then calculated theadditional cost and additional deaths averted versus thenext lowest cost strategy. The ratio of these 2 numbers(ie, the incremental cost per death averted) is the incrementalcost-effectiveness ratio.

Sensitivity analyses were performed to assess therobustness of key model parameters and to evaluatethe effect of alternative assumptions on model outcomes.To explore the cost effectiveness of thromboprophylaxisin patients with different comorbidity andrisk profiles, we analyzed subgroups of patients fromthe MEDENOX trial with heart failure, respiratory disease,or infectious disease.

 We varied the backgrounddeath rate and the underlying risk of DVT in patientsreceiving no prophylaxis, as well as the relative safetyand efficacy of the 2 active prophylaxis arms. Lastly,we examined the effect on our findings of changingassumptions about the cost of drug therapy, risk ofbleeding due to prophylaxis, progression from DVT toPE, and death from PE.

Base-case estimates of the occurrence of DVT, PE, andVTE-related death in a cohort of 10 000 acutely ill generalmedical inpatients are presented in 

. The riskof each of these outcomes is lowest among patientsreceiving thromboprophylaxis with enoxaparin and highestamong those receiving no prophylaxis. Compared tono thromboprophylaxis, enoxaparin prophylaxis isexpected to prevent 860 cases of DVT, 171 cases ofPE, and 44 deaths, while UFH is expected to prevent776 cases of DVT, 155 cases of PE, and 28 deaths.

The total costs of thromboprophylaxis, adverseevents (related to both prophylaxis and treatment ofVTE), and diagnosis and management of DVT andPE are presented in 

. Patients receiving nothromboprophylaxis had the lowest total costs, followedby those receiving enoxaparinand UFH.

Results of the incremental analysiscomparing a strategy of no prophylaxiswith the 2 active prophylactic strategiesare presented in 

. Whencompared with no prophylaxis, prophylaxiswith enoxaparin was the morecost-effective strategy, at a cost of$9100 per death averted. Unfractionatedheparin prophylaxis was dominatedby enoxaparin prophylaxis, whichwas both less costly and more effectivein preventing deaths.

. Results for thesubgroups of patients with heart failure,respiratory disease, or infectious disease were similarto those for all acutely ill medical patients (

).For each subgroup, thromboprophylaxis with enoxaparindominated that with UFH, and costs per deathaverted for enoxaparin versus no prophylaxis were evenmore favorable than in the base case.

 Our findingsalso were relatively insensitive to variations in theassumed competing risk of death (10% in the base-caseanalysis). Eliminating the competing risk of deathmade the results slightly more favorable forenoxaparin. Increasing the underlying risk ofdeath to 20% increased the cost per deathaverted with enoxaparin versus no prophylaxisby only about $1000 and did not changethe dominance of enoxaparin over UFH. Themodel was more sensitive to changes in theassumed risk of DVT. When we reduced therisk of DVT in all groups by one half (ie, to2.8% with enoxaparin, 3.3% with UFH, and7.1% with no prophylaxis), the cost per deathaverted for enoxaparin versus no prophylaxisincreased to $56 300, and enoxaparin continuedto dominate UFH. In contrast, when weincreased the risk of DVT by one half (ie, to8.3% with enoxaparin, 9.9% with UFH, and21.3% with no prophylaxis), both activemethods of prophylaxis were less costly andmore effective than no prophylaxis, withenoxaparin continuing to dominate UFH.When we conducted a similar analysis inwhich we simultaneously varied the risk ofbleeds with both enoxaparin and UFH from 50% to 150%of the base-case estimates, we found that enoxaparindominated UFH under both the high-risk and low-riskscenarios, with cost per death averted versus no prophylaxisranging from about $5000 assuming lower riskof bleeds to $14 000 assuming higher risk of bleeds.

Effectiveness and Side Effects of Enoxaparin vsUFH.

 To determine if our results depended on theassumption that enoxaparin had an efficacy advantageover UFH, we assumed equal efficacy (ie, 5.5% probabilityof DVT) for both methods of prophylaxis. Under thisassumption, enoxaparin remained both less costly andmore effective than UFH because of the reduced risk ofHIT and hemorrhage. Similarly, enoxaparin continuedto dominate UFH when equal rates of hemorrhage wereassumed for the 2 prophylactic strategies. When bothequal efficacy 

 equal rates of hemorrhage wereassumed, we found that UFH was no longer dominatedby enoxaparin, and the incremental cost effectiveness ofenoxaparin versus UFH was $43 256 per death averted.

. To examine the sensitivityof our results to changes in drug costs, we calculatedthe drug price at which enoxaparin would nolonger dominate UFH. We found that, up to a per-doseprice of $37.42 for enoxaparin (vs the base-case of$24.46), the cost per death averted with enoxaparin islower than with UFH. We also examined the sensitivityof our results to the assumed risk of progressionfrom DVT to PE, both with and without treatment, andthe probability of death due to treated or untreated PE.Varying each of these parameters from 50% to 150%of the base-case estimate, we found that our resultswere relatively insensitive to these assumptions. Foreach of these scenarios, thromboprophylaxis withenoxaparin was both less costly and more effectivethan UFH, and the incremental cost effectiveness ofenoxaparin versus no prophylaxis was less than$21 000 per death averted.

Our analysis highlights a number of important issuesrelated to the choice of thromboprophylactic strategyfor medical inpatients. First, the results of our base-caseanalysis indicate that, given the limitations andassumptions of the model, if the societal value of preventinga VTE-related death among acutely-ill medicalpatients is at least $9100, then the use of thromboprophylaxiswith LMWH among these patients can be consideredcost effective. If each death averted results ina gain of just one quality-adjusted life-year, this marginalcost is well below the often-cited threshold of$50 000 per quality-adjusted life-year gained.

 Moreover,despite higher drug acquisition costs, thromboprophylaxiswith enoxaparin dominates UFH by beingboth less costly and more effective.

In sensitivity analyses, enoxaparin remained costeffective in all scenarios examined. The cost-effectivenessadvantage of enoxaparin in our model may be seenas due to our assumptions that this drug has greaterefficacy as well as a more favorable adverse-event profilethan UFH, especially with respect to HIT. But sensitivityanalyses showed that even without an efficacyadvantage 

 a lower risk of bleeding complications,the incremental cost per death averted with enoxaparinversus UFH is less than $50 000. This suggeststhat the reduction in the risk of HIT alone may warrantthe use of this LMWH.

Our sensitivity analyses also indicate that, althoughthe incremental cost effectiveness of thromboprophylaxiswith a LMWH versus no thromboprophylaxis issomewhat sensitive to changes in the assumed underlyingrisk of VTE in untreated patients, the incrementalcost effectiveness of enoxaparin exceeds $50 000only slightly, even when this risk is halved. This suggeststhat thromboprophylaxis with enoxaparin may bea cost-effective strategy even among medical inpatientsat relatively low risk of VTE.

Our findings are qualitatively similar to those of 4recently published studies that evaluated the cost effectivenessof thromboprophylaxis with LMWH versusplacebo in medical patients from Canada,

 Our findings are alsogenerally consistent with the published studies in thesurgical population. A number of studies have examinedthe cost effectiveness of LMWH prophylaxis aftertotal hip replacement surgery and have found it to becost effective versus both warfarin

 populationsreported similar results, while a study comparingthromboprophylaxis with LMWH versus UFH after colorectalsurgery

 found UFH to be the more cost-effectivestrategy. Although most of these studies did notreport cost per death averted in US currency, the onestudy that did

 reported a cost-effectiveness ratio of$12 000 per death averted for enoxaparin versus warfarinin total hip replacement surgery, which is in linewith our finding of $9100 per death averted.

September 2004

HMORN Abstracts

Consumers' Use of the Internet for Health Insurance

The Role of Research in Integrated Healthcare Systems: The HMO Research Network

Cost Effectiveness of Thromboprophylaxis With a Low-Molecular-Weight Heparin Versus Unfractionated Heparin in Acutely Ill Medical Inpatients

Crossing the Digital Divide: Evaluating Online Communication Between Patients and Their Providers

Experiences of Patients Who Were Early Adopters of Electronic Communication With Their Physician: Satisfaction, Benefits, and Concerns

Comparison of Hospital Costs and Length of Stay Associated With General Internists and Hospitalist Physicians at a Community Hospital

Taking Stock at 2 Years - Continuing the Journey

The Influence of Year-end Bonuses on Colorectal Cancer Screening