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H S Luft

Publications and source records attributed to H S Luft.

At least 55 records · Page 3Linked to original sources
PubMed1994

Managed care plan performance since 1980. A literature analysis.

OBJECTIVE: To compare the health care utilization, expenditure, quality of care, and satisfaction since 1980 of enrollees in managed care and indemnity plans. DATA SOURCES AND STUDY SELECTION: Studies selected met the following criteria: data from 1980 forward, private insurance or Medicare enrollees, a comparison group, a reasonable attempt at statistical adjustment for noncomparable managed care and indemnity plan enrollees, and peer-reviewed findings (with two exceptions). Few studies on preferred provider organization plan performance met the selection criteria. DATA SYNTHESIS: Compared with indemnity plans, health maintenance organization plans had somewhat lower hospital admission rates, 1% to 20% shorter hospital length of stay, the same or more physician office visits per enrollee, less use of expensive procedures and tests, greater use of preventive services, mixed results on outcomes, and somewhat lower enrollee satisfaction with services but higher satisfaction with costs. The evidence does not support the hypothesis that prepaid group practice or staff model health maintenance organizations are more effective than individual practice association or network model health maintenance organizations. CONCLUSIONS: Although this literature analysis found several clear patterns of results, several factors, including unmeasured selection bias, diverse and rapidly changing health plans and local market conditions, and relatively few research results, suggest that generalizations must be made with caution.

Health Care Costs↗
PubMed1994

A comparison of administrative versus clinical data: coronary artery bypass surgery as an example. Ischemic Heart Disease Patient Outcomes Research Team.

Health services researchers rely heavily on administrative data bases, but incomplete or incorrect coding may bias risk models based on administrative data. The best method for validating administrative data is to collect detailed information about the same cases from independent sources, but this approach may be too costly or technically difficult. We used data on coronary artery bypass surgery from four sites (Duke University; Minneapolis--St Paul; California; and Manitoba) to demonstrate an alternative approach for assessing diagnostic coding and to explore the implications of miscoding. The first two sites have clinical data; the second two have administrative data. The prevalences of 14 comorbidities and the associated risk ratios for short-term mortality were compared across data sets. Some comorbidities could not be precisely mapped to ICD-9-CM. Chronic or asymptomatic conditions such as mitral insufficiency, cardiomegaly, previous myocardial infarction, tobacco use, and hyperlipidemia were far less prevalent in administrative data than in clinical data. The prevalence of diabetes, unstable angina, and congestive heart failure were similar in administrative and clinical data. Estimates of relative risk derived from clinical data equalled or surpassed those derived from administrative data for all conditions. Hospitals should be encouraged to improve reporting of coexisting conditions on discharge abstracts and claims. In the meantime, researchers using administrative data should assess the vulnerability of their risk models to bias caused by selective underreporting.

Adult↗
PubMed1994

Managed care plans: characteristics, growth, and premium performance.

Over the past dozen years, network-based managed care plans have undergone a remarkable transformation. At the beginning of the 1980s, managed care plans occupied a niche in a marketplace dominated by indemnity insurance plans. By 1993, managed care plans accounted for a growing majority of health plan enrollees. Moreover, enrollment in newer forms of managed care quickly surpassed that of the older group and staff model HMOs. Beginning as hybrids of elements of group and staff model HMO plans and of the old FFS system, these newer types of network-based plans have evolved as they have grown. Reacting to rapidly rising health care premium costs, employers wanted to move their employees and dependents relatively quickly into managed care plans. However, employers and enrollees were not prepared to make a rapid, wholesale shift from indemnity insurance and FFS towards the older, more restrictive type of group and staff model HMO plans. Moreover, intermediaries and providers were not prepared to accommodate such a shift, even if employers and employees wanted it to take place. Indeed, many of the major actors--employers, enrollees, health benefit intermediaries, physician networks, medical groups, hospitals and integrated delivery systems--have had to ascend very substantial managed care "learning curves". Although we have witnessed the overall movement of many enrollees from managed care plans that closely resembled the indemnity insurance plans toward plans with more similarities to the group and staff model HMOs, the extent of the changes has varied markedly among the dozens of local market areas, and even within local market areas. As the health care system evolves, the number and complexity of different types of contractual managed care relationships are increasing almost exponentially. The resulting difficulty in classifying managed care plans has implications for health services researchers. Increasingly, it is important to compare performance among health plans not at the level of the entire health plan, but at the level of the provider organizations or networks that actually provide health care services to enrollees. The Medical Outcome Study adopted this approach (12, 21, 35), providing useful insights into the dual effects of risk-sharing and provider organization on health care utilization, quality of care, and enrollee satisfaction. As well, if managed care plan classifications are to be meaningful, it is important to clearly specify the characteristics of the provider organization and the rest of the delivery system in whatever research is undertaken.(ABSTRACT TRUNCATED AT 400 WORDS)

Health Care Reform↗
PubMed1993

Chance, continuity, and change in hospital mortality rates. Coronary artery bypass graft patients in California hospitals, 1983 to 1989.

OBJECTIVE: To assess whether risk-adjusted mortality rates for hospitals reflect primarily chance variation. DESIGN: Observation over time. SETTING: All 115 California hospitals with five or more coronary artery bypass graft (CABG) patients in any year 1983 to 1989. PATIENTS: All CABG patients aged 18 years and older excluding those with other open heart procedures and percutaneous transluminal coronary angioplasty on the day of CABG surgery (n = 132,750). OUTCOME MEASURE: Inpatient mortality adjusted for age, gender, chronic comorbidities, timing of surgery, and presence of additional procedures. METHODS: Data were derived from routinely collected hospital discharge abstracts. Observed and expected semiannual mortality rates were examined for each hospital to identify consistent patterns over time. Using the quartile of patients with the highest predicted risk (average mortality, 10%), high- and low-outlier hospitals were identified from 2 consecutive years of pooled data and outcomes 2 years later were examined. Each hospital-year observation was also examined individually to identify outliers and to assess differences for observed and expected death rates, patient volume, and other characteristics. RESULTS: Some hospitals showed consistently lower-than-expected inpatient mortality. Some hospitals had periods of significantly higher-than-expected mortality followed by a correction. High-outlier hospitals that were selected based on 2 years of data had mortality rates 2 years later that averaged 31% above expected, while low-outlier hospitals had rates 2 years later that averaged 28% below expected. On a contemporaneous basis, high outliers had proportionately more transfers to other acute care hospitals and longer postoperative stays among survivors. CONCLUSIONS: Risk-adjusted outcomes for CABG patients derived from administrative data exhibit substantial patterns of consistency. Such patterns cannot be detected for low-risk patients but are evident for the top quartile of patients stratified by risk. Even with reporting lags and changes in hospital outcomes over time, a policy of channeling high-risk patients away from high-outlier hospitals and toward low-outlier hospitals could lower their overall risk-adjusted mortality rate by 45% [corrected].

Adult↗
PubMed1993

Use of coronary artery bypass surgery in the United States and Canada. Influence of age and income.

OBJECTIVE: To compare overall rates of coronary artery bypass surgery (CABS) in several Canadian and US jurisdictions and to compare use by age and income groups in the two countries. DESIGN: Survey, using computerized hospital discharge abstracts. SETTING: All nonfederal hospitals in New York, California, Ontario, Manitoba, and British Columbia between 1983 and 1989. PATIENTS: All adult residents of the five jurisdictions who underwent CABS in a hospital in their jurisdiction. RESULTS: Between 1983 and 1989, the CABS rates were consistently highest in California and lowest in the Canadian jurisdictions. In 1989, the age-adjusted rate of CABS in California (112.5/100,000 adults) was 27% higher than in New York (88.4/100,000) and 80% higher than in the three Canadian provinces combined (62.4/100,000). The CABS rates increased for those aged 65 years and older and decreased for those aged 20 to 54 years in all five jurisdictions. In 1989, CABS rates were three times higher in California than in Canada for those aged 75 years and older, and the higher rates for those aged 65 years and older accounted for 75% of the overall difference in rates between California and Canada. In Canada, CABS rates for the nonelderly varied little by income of area of residence, but in New York and California, rates increased steadily with the income of area of residence. CONCLUSION: Control over the supply of resources in Canada is associated with markedly lower CABS rates for the elderly than found in the United States. While overall rates are lower in Canada, the Canadian universal health insurance system reduces the influence of income on access to CABS found in the United States. However, even without universal health insurance, CABS rates for the nonelderly living in the poorest areas in California are similar to the rates for those living in the poorest parts of Canada.

Adult↗
PubMed1993

Estimating hospital admission patterns using Medicare data.

It is often necessary in health services research and strategic planning to simultaneously describe the geographic pattern of admissions to multiple hospitals. Obtaining the data necessary to accomplish this can often be problematic. In some states discharge abstract data on all admissions to all hospitals in the state are compiled and maintained by a government agency, but in 23 states these data are not available. Furthermore, problems arise when a substantial fraction of admissions cross state borders, such that data from more than one state is required for description of 'patient flows'. Individual hospitals typically maintain data on the geographic source of their own admissions, but are not likely to have access to such data regarding other hospitals in their area. Patient flow data on Medicare admissions are available for all states and are readily accessible, but heretofore it has not been known how closely the admission patterns of Medicare patients approximate those of other types of patients. We examine the accuracy of using data on Medicare admissions to estimate, at the hospital level, the admission patterns of other types of patients. Using zip code-to-hospital patient flow data for all non-federal hospitals in California, we calculated the correlation between Medicare admission patterns and those of three other groups of patients (other adults, pediatrics and obstetrics) for each hospital. For the majority of hospitals, Medicare data predict the admissions of other adults quite well, and the admissions of pediatric and obstetric admissions moderately well.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Border crossing for hospital care and its implications for the use of statewide data.

A major concern of researchers using state data sets for population-based analyses and market share studies in the health care sector is the potential bias caused by 'border crossing'--patients receiving care out of state. By using the Health Care Financing Administration (HCFA) discharge abstract files for 1987 and 1988, we found that 'border crossing' is not a serious problem for the two large states we examined. Only 4.4% of New York patients and 2.15% of California patients received care out of state. At the county and zip code level, 'border crossing' is more frequent but tends to be concentrated in areas adjacent to other states. Even excluding all zips with more than 10% of patients crossing the 'border' results in a small loss of patients (2.2% for New York and 1.0% for California).

Adolescent↗
PubMed1993

Health plan switching in anticipation of increased medical care utilization.

We compare rates and days of maternity and nonmaternity hospital admission for the years 1981 through 1984 for three groups of employees and dependents from a large private employer: those continuously enrolled in a fee-for-service (FFS) plan (N = 147,700), those continuously enrolled in a health maintenance organization (HMO) (N = 30,957), and those switching from the FFS plan to the HMO (N = 2,144). The rate of maternity admissions for plan switchers increased by 106% (P < 0.001) in the post-switch year compared with the pre-switch year, while maternity rates for continuing FFS-plan enrollees declined by 12% (P < 0.001) and rates for continuing HMO enrollees remained unchanged. Nonmaternity admission rates for switchers decreased by 19% (P = 0.079), consistent with the expectation that HMOs reduce these rates substantially, while rates for FFS-plan stayers increased 4% (P < 0.001) and those for HMO stayers remained unchanged. We conclude that employees often switch health plans when anticipating increased needs for maternity care and therefore that pre-switch rates of utilization are unreliable measures of the true magnitude of risk selection between HMOs and FFS plans.

California↗
PubMed1993

Coronary angioplasty. Statewide experience in California.

BACKGROUND: This report describes the in-hospital experience with percutaneous transluminal coronary angioplasty (PTCA) for the state of California in 1989. Data are derived from the statewide hospital discharge abstracts. METHODS AND RESULTS: A total of 24,883 PTCAs were performed; most patients (70%) were men and most procedures were single vessel (87%). About one fifth (19%) of patients had a principal diagnosis of acute myocardial infarction (AMI). Overall mortality was 1.4% and was higher in the AMI group (4.2%) versus the non-AMI group (0.8%, P = .0001). Mortality was higher for AMI patients having PTCA on the day of or day after admission (5.5%) versus those treated later (2.6%, P = .0001). Five percent of patients had coronary artery bypass surgery (CABG) after PTCA; CABG was performed on the same day as PTCA in 61.7% of cases. Patients presenting with AMI were more likely to have CABG (7.1%) than non-AMI patients (4.5%, P = .0001). Mortality associated with CABG was 7.3% and was higher in the AMI group (12.0%) than in the non-AMI group (5.5%, P = .0001). Factors predictive of increased mortality by bivariate analysis included age > 63 years (2.1% mortality versus 0.8% < or = 63, P = .01), female sex (1.9% versus 1.2% for men, P < .01), and the presence of diabetes (1.9% versus 1.3% for nondiabetics, P < .05). Multiple logistic regression showed that timings of PTCA with respect to admission (P = .004) and age (P = .05) were predictors of mortality, but female sex was predictive only in the non-AMI group (P = .03). Mean hospital charges were $19,597 (+/- SD, $18,213). Forty-two percent of the 110 hospitals performed more than the recommended minimum of 200 cases per year. The requirement for CABG during the same admission or the combined adverse outcome of CABG and/or death was increased in the lower-volume centers for both AMI and non-AMI patients (P < .001), although mortality alone was not. CONCLUSIONS: The mortality and need for CABG surgery in the statewide California PTCA experience is higher than that generally reported in the literature. In patients with an admitting diagnosis of AMI, the overall mortality was higher, as was the need for CABG and the associated CABG mortality. Most hospitals performed fewer than 200 PTCAs per year. Rates of CABG surgery and the combination of CABG and/or mortality, adjusted only for the presence or absence of AMI, were increased at the low-volume institutions.

Adolescent↗
PubMed1993

Managed care: past evidence and potential trends.

Enrollment in network-based managed care plans has grown rapidly, raising important questions about the actual impact of different types of managed care plans on health care use, expenditure, and quality of care. In this article, we analyze the literature on the performance of managed care plans relative to fee-for-service plans. We find strong evidence that staff- and group-model HMOs have lowered utilization and expenditure relative to fee-for-service while maintaining quality of care. The relatively sparse evidence is more mixed on the performance of newer forms of managed care organizations (MCOs). We also speculate on future trends in network-based managed care. It is likely that employers will increase their economic leverage with managed care firms, accelerating processes that are leading to greater concentration of marketshare among managed care firms. In turn, newer forms of MCOs will increase their economic leverage with providers, which will help MCOs contain costs and monitor quality. Some of the newer MCOs will adapt important features of staff- and group-model HMOs, including increased emphasis on provider selection and reselection.

Costs and Cost Analysis↗
PubMed1993

Anatomy of health care reform proposals.

The current proliferation of proposals for health care reform makes it difficult to sort out the differences among plans and the likely outcome of different approaches to reform. The current health care system has two basic features. The first, enrollment and eligibility functions, includes how people get into the system and gain coverage for health care services. We describe 4 models, ranging from an individual, voluntary approach to a universal, tax-based model. The second, the provision of health care, includes how physician services are organized, how they are paid for, what mechanisms are in place for quality assurance, and the degree of organization and oversight of the health care system. We describe 7 models of the organization component, including the current fee-for-service system with no national health budget, managed care, salaried providers under a budget, and managed competition with and without a national health budget. These 2 components provide the building blocks for health care plans, presented as a matrix. We also evaluate several reform proposals by how they combine these 2 elements.

Delivery of Health Care↗
PubMed1993

Calculating the probability of rare events: why settle for an approximation?

OBJECTIVE: Health services researchers often need to compute the probability of observing a certain number of events when only a few such events are expected. Our objective is to show that the standard approaches (Poisson, binomial, and normal approximations) are inappropriate in such instances, and to suggest an alternative. DATA SOURCES: Patients undergoing cholecystectomy (34,234) in 465 California hospitals in 1983 are used to demonstrate the biases arising from various methods of calculating the probability of observing a given number of deaths in each hospital. Similar data from other procedures and diagnoses with lower and higher mortality rates are also used for illustration. STUDY DESIGN: The computational methods to derive probabilities using the Poisson, normal, simulation, and exact probabilities are discussed. Using a previously developed risk factor model, the probability of observing the actual number of deaths (or more) is calculated given the expectation of death for each patient in each hospital. Results for the four methods are compared, showing the types of random and systematic errors in the Poisson, normal, and simulation approaches. DATA COLLECTION: Routinely collected hospital discharge abstract data were provided by the California Office of Statewide Planning and Development. PRINCIPAL FINDINGS: The Poisson and normal approximations are often biased substantially in calculating upper-tail p-values, especially when the expected number of adverse outcomes is less than five. Simulations allow unbiased calculations, and the degree of random error can be made arbitrarily small given enough trials. Exact calculations using a simple recursive algorithm can be done very efficiently on either a mainframe or personal computer. For example, the whole set of cholecystectomy patients can be assessed in less than 90 seconds on a Macintosh. CONCLUSIONS: Calculating the probability of observing a small number of events using standard approaches may result in substantial errors. The availability of a simple and inexpensive method of calculating these probabilities exactly can avoid these errors.

Bias↗
PubMed1993

Choice of hospital for delivery: a comparison of high-risk and low-risk women.

OBJECTIVE: This article tests whether or not the factors that affect hospital choice differ for selected subgroups of the population. DATA SOURCES: 1985 California Office of Statewide Health Planning and Development (OSHPD) discharge abstracts and hospital financial data were used. STUDY DESIGN: Models for hospital choice were estimated using McFadden's conditional logit model. Separate models were estimated for high-risk and low-risk patients, and for high-risk and low-risk women covered either by private insurance or by California Medicaid. The model included independent variables to control for quality, price, ownership, and distance to the hospital. DATA EXTRACTION: Data covered all maternal deliveries in the San Francisco Bay Area in 1985 (N = 61,436). ICD-9 codes were used to classify patients as high-risk or low-risk. The expected payment code on the discharge abstract was used to identify insurance status. PRINCIPAL FINDINGS: The results strongly reject the hypothesis that high-risk and low-risk women have the same choice process. Hospital quality tended to be more important for high-risk than low-risk women. These results also reject the hypothesis that factors influencing choice of hospital are the same for women covered by private insurance as for those covered by Medicaid. Further, high-risk women covered by Medicaid were less likely than high-risk women covered by private insurance to deliver in hospitals with newborn intensive care units. CONCLUSIONS: The results show that the choice factors vary across several broadly defined subgroups of patients with a specific condition. Thus, estimates aggregating all patients may be misleading. Specifically, such estimates will understate actual patient response to quality of care indicators, since patient sensitivity to quality of care varies with the patients' risk status.

Choice Behavior↗
PubMed1992

Costs and coverage. Pressures toward health care reform.

Signs of discontent with the health care system are growing. Calls for health care reform are largely motivated by the continued increase in health care costs and the large number of people without adequate health insurance. For the past 20 years, health care spending has risen at rates higher than the gross national product. As many as 35 million people are without health insurance. As proposals for health care reform are developed, it is useful to understand the roots of the cost problem. Causes of spiraling health care costs include "market failure" in the health care market, expansion in technology, excessive administrative costs, unnecessary care and defensive medicine, increased patient complexity, excess capacity within the health care system, and low productivity. Attempts to control costs, by the federal government for the Medicare program and then by the private sector, have to date been mostly unsuccessful. New proposals for health care reform are proliferating, and important changes in the health care system are likely.

Delivery of Health Care↗
PubMed1991

Service patterns in local hospital markets: complementarity or medical arms race?

In this paper we investigate how the availability of selected services in individual hospitals is influenced by the number of neighbors who are potential or actual competitors. Hospitals offer a wide range of services, and some services may display a complementary pattern while others may contribute to a competitive medical arms race. We will examine the types of services that show these opposite patterns to analyze the dynamics that have characterized local hospital service decisions.

Catchment Area, Health↗
PubMed1991

Modeling the effect of hospital charges and quality on choice.

The authors apply a conditional choice model to simulate the results of patient and physician choices of hospitals for a specific surgical procedure in response to improvements in quality or changes in charges. The model includes all zip code areas and relevant hospitals in a large metropolitan area and estimates the impact on admissions at each hospital. It can be used to estimate both the impact of decisions by a given hospital and the potential responses of competitors, as well as the effects of selective contracting with hospitals by certain payors.

Choice Behavior↗