Changes in CT utilization between 1981 and 1984: implications for Medicare payment for MR imaging under the prospective payment system

In the absence of data on current or likely patterns of use of magnetic resonance (MR) imaging, use of computed tomography (CT) at one institution in 1981 and 1984 was analyzed to provide data relevant to current federal deliberations regarding Medicare payment for inpatient MR imaging. Between 1981 and 1984 inpatient CT utilization increased 59%, primarily due to a 265% increase in body CT. In 1984 inpatients who underwent at least one CT procedure were as likely to undergo more than one procedure as to undergo only one. CT procedures were performed in a high proportion of diagnosis-related groups (DRGs), with more than one-half of head CT procedures performed in non-neurologic DRGs. Given the similarities between clinical applications of CT and MR imaging, these findings regarding CT utilization have the following implications: (a) a delay in recalibration of DRG payment rates may not take account of expected growth in utilization of MR imaging, (b) a DRG "add-on" for MR imaging should reflect the likelihood that more than one MR imaging procedure will be performed in many hospitalizations, and (c) adjustments in DRG payments for MR imaging should not be limited to the 35 neurologic DRGs.

Elective foot surgery: relative roles of doctors of podiatric medicine and orthopedic surgeons

We examined the roles of Doctors of Podiatric Medicine (DPMs) and orthopedic surgeons in the provision of foot surgery by analyzing the 1982 computerized claims of over 1.1 million federal employees, retirees, and family members. We found that DPMs provided over 60 per cent of all elective insured foot surgery. Without being able to adjust for the severity of the patient's underlying condition or the appropriateness and outcome of the surgery, the average per procedure charge submitted by an orthopedist was 17 per cent higher than that of a DPM; orthopedists were five times as likely to perform a procedure on an inpatient basis, and admitted patients to a hospital had longer stays; DPMs perform a greater number of procedures per episode, but their overall charges during the average foot surgery episode were 30 per cent lower, primarily because of their lower hospitalization rates. The possible impact of recent changes in health care delivery on the DPM/orthopedist practice comparison are discussed as are several questions regarding the quality and need of the care provided by these two groups.

Assessing a methodology for physician requirement forecasting. Replication of GMENAC's need-based model for the pediatric specialty

Methodologies for determining levels of U.S. physician requirement are as complex as they are controversial. One long-standing controversy surrounds the advantages of an epidemiologic need-based forecasting model over an economic demand-based model. This paper examines the need-based requirement approach as recently developed by the Graduate Medical Education National Advisory Committee (GMENAC). This approach is assessed for the pediatric specialty by replicating the original model using data derived from three large HMOs. These data were empirically obtained from the computerized visit records of more than 10,000 children at each of the three plans and normatively from Delphi panels consisting of pediatric practitioners at those same sites. Results indicate that if U.S. pediatrician requirement was estimated on the basis of HMO practice data, rather than GMENAC's national ideals, fewer physicians would be needed. The pediatric requirement based on local Delphi panel judgments was lower still, due in great part to the suggestion of increased delegation rates to nonphysician providers. Implications of this comparative analysis for the GMENAC need-based methodology and future physician requirement modeling efforts are discussed.

Nurse practitioner and physician assistant practices in three HMOs: implications for future US health manpower needs

This study empirically examines the practices of non-physician providers (NPPs) within three large competitive health maintenance organizations (HMOs), as well as the physicians' and NPPs' views regarding the ideal role of NPPs. These roles are compared with NPP delegation patterns incorporated in the modeling methodology developed by the Graduate Medical Education National Advisory Committee (GMENAC). GMENAC recommended relatively high levels of delegation by physicians to NPPs. One of the HMO sites made use of NPPs at rates even higher than GMENAC's national ideals, while the rates at the other two were lower. The normative ideals for pediatric NPPs developed at each HMO were consistently higher than their actual roles. Concerns with acceptance and the role of NPPs are clearly no longer issues. Instead, the limits on NPP involvement appear to relate to considerations of costs, availability, and the increasing numbers of physicians competing for similar opportunities.

A comparison of the requirements for primary care physicians in HMOs with projections made by the GMENAC

We compared staffing patterns in primary care specialties in three large health maintenance organizations (HMOs) with the national requirements for physicians in 1990 projected by the Graduate Medical Education National Advisory Committee (GMENAC). The HMOs varied in their use of nonphysician providers, family practice specialists, and subspecialists in internal medicine. Nevertheless, projections based on the average experience of these HMOs suggest that 20 percent fewer primary care physicians for children and 50 percent fewer primary care physicians for adults will be needed to meet national primary care needs in 1990 than projected by the GMENAC. As enrollment in HMOs continues to grow, their impact on national requirements for medical personnel will increase. The variety of staffing patterns found among HMOs operating in highly competitive markets suggests the importance of considering alternative configurations for meeting national requirements for primary care.

Measuring need for mental health services in a general population

This article presents measures of need for mental health services estimated from the 1981 Eastern Baltimore Mental Health Survey, one of five sites participating in the NIMH Epidemiologic Catchment Area Program. Data were collected on the prevalence of specific psychiatric disorders, as determined by the standardized Diagnostic Interview Schedule (DIS), functional status, personal characteristics, patterns of medical and mental health care, and sources of care used. Need is based on mental health services use in the prior 6 months or the presence of two or more manifestations of emotional problems: a) one or more DIS disorders present in the past 6 months, b) a General Health Questionnaire (GHQ) score of four or more current symptoms, or c) the respondent's report of having been unable to carry out usual activities in the past 3 months for at least 1 entire day because of an emotional problem. Approximately 14% of adults met the criteria for need, half of whom had made no mental health visits in the prior 6 months and were considered to have unmet need. Need for care was influenced by a variety of sociodemographic and economic characteristics: it was low among the aged and high among persons living alone and the poor on Medicaid. The proportion of need that was unmet varied less but was relatively large for two groups, the aged and nonwhites. Those on Medicaid through public assistance were more likely to have their need met than the near poor.

Hospital payment effects on acute inpatient care for mental disorders

We examined the extent to which inpatient care for patients with mental disorders in general, acute care hospitals responds differently to two types of prospective hospital payment. In Maryland, hospitals have been regulated since 1976 under two forms of payment based on per-service and per-case definitions of hospital output. The study utilizes a 20% sample of 58,000 mental-disorder discharges from 21 per-case- and 24 per-service-reimbursed hospitals in Maryland between fiscal years 1977 and 1980. The effects of payment method on length of stay are examined through the application of multivariate regression models. The empirical results are generally consistent with the notion that the per-case payment method provides some incentives for hospitals to reduce the length of stay. The regulatory effects, however, vary with patient characteristics, particularly by diagnosis.

The effect of hospital payment methods on the pattern and cost of mental health care

The authors report on a study of the impact of a prospective payment method on hospital charges and mix of services provided to a group of Medicare patients treated for mental disorders in general acute care hospitals in Maryland. The study focused on per case reimbursement, under which hospitals are guaranteed a level of total revenue based on the number and case mix of discharges, and examined its effect on hospital charges during an index admission and on hospital and non-hospital charges over a three-month period following the index admission. The results suggest that per case reimbursement provides incentives to reduce the cost of one hospital stay, but this cost reduction is possibly offset by a higher readmission rate or by higher readmission charges. The authors conclude that the impact of the per case payment method on the total cost of mental health care over a specific period of time is insignificant, but that the payment method may influence the pattern of care.

A longitudinal study of offset in the use of nonpsychiatric services following specialized mental health care

This study examines the use of nonpsychiatric services by mentally ill persons following the receipt of specialized mental health care, frequently referred to as the "offset effect." A total of 9,761 persons enrolled during 1975 in the Columbia Medical Plan, a prepaid group practice in Columbia, Maryland, were studied over a 5-year period. Enrollees were classified into three groups: Treated--mental disorder diagnosis in 1975 and specialized mental health care in 1975; Untreated--mental disorder diagnosis in 1975 but no specialized mental health care in that year; and Comparison--neither mental disorder diagnosis nor specialized mental health care in 1975. The nonpsychiatric utilization for these groups was compared for 1973-1977. Specialized mental health care appears to have a short-term effect on nonpsychiatric utilization by attenuating the peak in use. Mentally ill persons without specialized mental health care in 1975 also reduced their use of nonpsychiatric services in 1976-1977. The utilization changes were more likely to occur in primary care departments, rather than nonpsychiatric specialty care departments. A diagnosis of mental disorder in either 1973 or 1974 was associated with a larger offset effect.

Episodes of psychiatric care and medical utilization

This study examines the reduction in medical care utilization after mental health treatment, also known as the offset effect. With data from a computerized ambulatory care information system, an episode-of-care method is used to characterize the mental health care received by patients in a prepaid group practice. The characteristics of the psychiatric episodes, such as duration, type of therapy, and number of visits, are examined in relation to the degree of offset effects among psychiatric patients. The results indicate that offset effects are most pronounced for a variety of characteristics related to the psychiatric episode of care including brief, high-intensity therapy, treatment for transient rather than chronic mental illness, and individual rather than group therapies. Finally, this study replicates two major findings in the offset literature: the characteristic peaking of medical use before mental health care and the short-term nature of the offset effect.

Episode-based efficiency comparisons for physicians and nurse practitioners

Most previous studies comparing the efficiency of new health practitioners with that of physicians have used the visit as the basic unit of output. Several researchers have noted, though, that the episode is a conceptually superior output unit in several respects, although it is more complex to deal with methodologically. This study demonstrates the application of episode-based methods for comparing the efficiency of physicians with that of nurse practitioners. Data are drawn from the information system of the Columbia Medical Plan and from observations of provider time inputs. The analysis is confined to care episodes for otitis media and sore throat in the Department of Pediatrics. Results indicate that per episode costs with nurse practitioners as the initial provider are approximately 20 per cent below the costs of episodes in which physicians are the initial provider. Examination of a limited amount of data on patient-reported measures of effectiveness indicates that while nurse practitioners' care is less costly, it is not less effective. These findings are particularly interesting in light of recent doubts expressed about cost-savings from using new health practitioners, and particularly nurse practitioners, in group practice settings.

Use of general medical care services by persons with mental disorders

Data are presented on the medical diagnoses and the type of general medical services used by persons with mental disorder diagnoses. This study is based on the 1975 experience of registrants in four medical programs contained in three organizational settings. The data on services were retrieved from each program's automated date system. The percent of patients seen in general medical departments receiving a mental disorder diagnosis ranged from 4.8% to 13.6% among the four programs. Patients with mental disorder diagnoses visit general medical departments from 11/2 to two times as frequently as patients without such diagnoses. Persons with a diagnosed mental disorder are likely to receive care for conditions in more International Classification of Diseases categories than other patients, and are more likely to receive a diagnosis for ill-defined conditions, signs, and symptoms.

Changing patterns of graduate medical education

Postgraduate medical education underwent substantial change during the 1970s: medical-school classes grew, the internship year was eliminated, and the numbers of M.D.s entering primary-care specialties increased. The purpose of this study is to develop a planning model of graduate medical education that can project the impact of these and other changes on the numbers and specialty mix of physicians completing training. The model is applied to an analysis of trends in graduate medical education and to the probable consequences of policy recommendations made by the Graduate Medical Education National Advisory Committee (GMENAC). The results show that the trend toward increasing percentages of M.D.s entering primary-care specialties from 1970 to 1976 changes to no increase from 1976 to 1980. Thus, the GMENAC policy recommendation to increase primary care further is not likely to occur spontaneously in the near future.

Episodes of psychiatric utilization

The continued growth of outpatient psychiatric care has been accompanied by a large number of research studies concerning the determinants of psychiatric utilization. One of the major limitations of these efforts has been the inability to go beyond distributional data on the use of services. This article describes a methodology for generating episodes of psychiatric care given a data set with a small amount of routinely collected data present in many medical information systems. Both demographic and medical characteristics are significantly associated with health services resource use as defined by the number of visits in an episode. A model predicting recurrent episodes of care is also described. The general utility of this approach and the substantive implications of the specific results are discussed.

Male and female physician career patterns: specialty choices and graduate training

During the decade of the seventies the proportion of entering U.S. medical school classes consisting of women increased from 9 to 25%. National data on 74,265 physicians from seven graduation cohorts (1970 to 1976) reveal that this phenomenon has resulted in a trend toward convergence of male and female career patterns in several important areas: specialty choice during graduate medical education, patterns of switching specialties and subspecialization, and duration of graduate medical training. In addition, whereas both sexes show an increased tendency to select general internal medicine and family practice, the lower rate at which women subspecialize within pediatrics and the increasing rate at which they select obstetrics/gynecology suggest a shifting orientation toward primary care among women.

Reorganization of a medical house staff (firm system): its effect on accessibility and continuity of care

In 1975, the Johns Hopkins Medical house staff was reorganized into four Firms. Each Firm provides inpatient and outpatient care to a group of patients. Two of the goals of the reorganization were to improve accessibility and continuity of care. This study, based on a before and after research design utilizing routinely collected data, sought to determine whether these goals had been attained. Accessibility was assessed by observing changes in waiting time for appointments, broken appointments, and number of patients seen before their scheduled appointments. The results showed that mean waiting time for a Medical Clinic appointment fell from 15 days to 1 day (p < 0.01); broken appointments for new patients fell from 54% to 34% (p < 0.01); no significant changes occurred in broken appointments for old clinic patients (34% vs 32%); and patients seen before their scheduled appointments increased from 30% to 38% (p < 0.001). Continuity was assessed by observing changes in use of emergency and walk-in clinic services, the proportion of Medical Clinic patients lost to follow-up care, the proportion of hospital readmissions returning to the same nursing unit, and the proportion of patients discharged from the hospital who returned to the Medical Clinic. The results showed that use of emergency and walk-in clinic services fell slightly, from 24% of all visits before to 22% of all visits after the Firm System (p < 0.001); no change occurred in the proportion of patients lost to Medical Clinic follow-up (21% before and after the Firm System); the proportion of hospital readmissions returning to the same nursing unit increased from 35% to 73% (p < 0.005); and the proportion of patients discharged from the hospital who returned to the Medical Clinic increased from 21% to 35% (p < 0.001). These data suggest that implementing the Firm System led to improvement in several selected aspects of accessibility and continuity of care but that further improvements could be made.

The impact on utilization of a copayment increase for ambulatory psychiatric care

The impact of a copayment increase on the utilization of psychiatric services in a prepaid group practice program is examined. Data are presented on utilization at the Columbia Medical Plan (Columbia, Maryland) two years before and two years after the copayment increase. There was a highly transient response to the increse in the copayment for psychiatric care. The year of the copayment increase was characterized by a small decline in the proportion of enrollees using psychiatric care, and a slight decrease in the utilization rate. These declines were short-lived, and utilization returned to previous levels one year after the copayment increase.