Geographic variation in expenditures for physicians' services in the United States

BACKGROUND

The national volume-performance standard recently implemented by Medicare does not account for geographic variation in expenditures for physicians' services. To study this variation, we examined expenditures for physicians' services in all metropolitan areas in the United States.

METHODS

We used Medicare claims data for 1989 to measure rates of service use for beneficiaries living in the 317 U.S. metropolitan statistical areas (MSAs). The variables investigated were rates of admission to the hospital, payments to physicians for inpatient care per admission and per beneficiary, payments to physicians for outpatient care per beneficiary, and overall payments to physicians per beneficiary. Expenditures were measured in terms of allowed charges as adjusted to reflect prevailing charges in each MSA. Rates of use were adjusted for age and sex, with the exception of the variable for payments to physicians for inpatient care per admission, which was adjusted for case mix.

RESULTS

Expenditures for the delivery of physicians' services to Medicare beneficiaries varied markedly among MSAs, with those for the areas with the lowest and the highest rates differing at least twofold on each measure. The measures for specific areas varied in parallel: areas with high rates of admission tended to have high levels of payment to physicians for inpatient care per admission, and areas with high payments for inpatient services tended to have high payments for outpatient services. Expenditures were not related to the number of physicians per capita but were lower in MSAs with a high proportion of primary care practitioners. The variation persisted when the 25 largest MSAs were examined; for total payments to physicians per beneficiary, there was a twofold difference between the area with the lowest rate and that with the highest, San Francisco ($872) and Miami ($1,874). The states with the highest overall payments to physicians per beneficiary were Florida, Louisiana, and Michigan.

CONCLUSIONS

The marked variation among metropolitan areas in payments to physicians underscores the lack of consensus among physicians about which services are required. Moreover, the practice style in a given community appears to be influenced not by the aggregate supply of physicians but rather by the mixture of primary care physicians and specialists.

Hypnotic analgesia: dissociated experience or dissociated control?

High-hypnotizable subjects (n = 18) were superior to low-hypnotizable subjects (n = 18) in the extent of pain reduction produced by hypnotic analgesia and by a stress-inoculation procedure. However, stress inoculation but not hypnotic analgesia impaired performance on a cognitively demanding task that competed with pain reduction for cognitive resources. This outcome implies that hypnotic analgesia occurs with little or no cognitive effort to reduce pain and challenges the social psychological model of hypnosis. The findings are also inconsistent with the notion of dissociated experience, which proposes that pain and the cognitive efforts to reduce it are cut off from consciousness by an amnesialike barrier. However, the results do support the notion of dissociated control, which proposes that suggestions for hypnotic analgesia directly activate pain reduction and thereby avert the need for cognitive strategies to reduce pain.

Physician inpatient order writing on microcomputer workstations. Effects on resource utilization

OBJECTIVE

To assess the effects on health care resource utilization of a network of microcomputer workstations for writing all inpatient orders.

DESIGN

Randomized controlled clinical trial.

SETTING

Inpatient internal medicine service of an urban public hospital.

SUBJECTS

A total of 5219 internal medicine patients and the 68 teams of house officers, medical students, and faculty internists who cared for them.

INTERVENTION

Microcomputer workstations, linked to a comprehensive electronic medical record system, for writing all inpatient orders.

MAIN OUTCOME MEASURES

Total inpatient charges for each admission and charges for specific categories of orders. A time-motion study of selected interns assessed the ordering system's time consumption.

RESULTS

Intervention teams generated charges that were $887 (12.7%) lower per admission than did control teams (P = .02). Significant reductions (P < .05) were demonstrated separately for bed charges, diagnostic test charges, and drug charges. Reductions of similar proportion and statistical significance were found for hospital costs. The mean length of stay was 0.89 day shorter for intervention resident teams (P = .11). Interns in the intervention group spent an average of 33 minutes longer (5.5 minutes per patient) during a 10-hour observation period writing orders than did interns in the control group (P < .0001).

CONCLUSIONS

A network of microcomputer workstations for writing all inpatient orders significantly lowered patient charges and hospital costs. This would amount to savings of more than $3 million in charges annually for this hospital's medicine service and potentially tens of billions of dollars nationwide. However, the system required more physician time than did the paper charts. Research at other sites and system advances to reduce time requirements are warranted.

Platelet adhesion at low shear rate: study of a normal population

The use of oral contraceptives (OCs) has been associated with vascular complications. The mechanism(s) by which OCs predispose to thrombotic events remains unclear. Recent studies have demonstrated that postmenopausal (PM) women who take estrogen replacement therapy (ERT) have a decreased incidence of myocardial infarction compared to those who do not take ERT. This study was undertaken to determine if healthy individuals have differences in platelet adhesion depending on hormonal status. Men, PM women taking ERT, PM women not taking ERT, OC users, and premenopausal women not taking any medications were studied. Platelet studies were performed in a Hele-Shaw flow chamber at a low shear rate using platelet-rich plasma. The platelet adhesion process to subendothelial components: fibronectin, collagen I and collagen III was recorded using a 35 mm camera mounted on an inverted microscope. Photographs were taken at 30 second intervals for a total of 12 minutes and analyzed using a modified computer program which provided a numerical account of platelet adhesion. OC users had significantly higher platelet adherence to fibronectin, collagen I and collagen III compared to all other groups. All other study groups had similar platelet adhesion independent of hormonal status. These findings suggest that OCs cause increased platelet adhesion in some individuals and this may be one of the mechanisms by which OCs contribute to thrombotic events.

Medicaid case management: Kentucky's Patient Access and Care Program

Since 1981, States have been experimenting with Medicaid managed care programs to improve access and continuity of care and to contain costs by reducing inappropriate and unnecessary utilization. To determine the impact of primary care case management (PCCM) on utilization, the authors examine data from the Kentucky Patient Access and Care program (KenPAC). Using monthly utilization data from 1984 to 1989 and an interrupted time-series research design, the authors find that PCCM reduces the use of independent laboratory, physician, emergency department, and outpatient hospital services. PCCM does not appear to affect utilization of inpatient hospital services or prescription drugs.

How do Medicare physician fees compare with private payers?

Under the new fee schedule, Medicare physician fees are 76 percent of private fees. Consistent with the intent of payment reform, Medicare physician fees more closely approximate private fees for visits (93 percent) than for surgery (51 percent) and in rural areas as compared with large metropolitan areas. Variation in private fees across the country is considerably greater than it is for Medicare fees. Consequently, Medicare fees are most generous in areas that compare least favorably with the private market because private fees in these areas are well above average. These results shed light on the impact of the fee schedule and on the implications of using Medicare payment methods as part of a broad-based health reform.

Validation of probabilistic predictions

Current advances in high-speed computing and increased availability of statistical software have led to widespread use of statistical methods for the development of computerized protocols predictive of binary health outcomes. If these predictive algorithms are to be used in settings other than those for which they were developed, e.g., applied in a different geographic setting or extrapolated for use in a slightly different population, then they should be carefully validated to ensure appropriate application. Miller et al. (Stat Med. 1991) provided a comprehensive methodology for external validation of logistic prediction models, and applied these methods in a temporal validation setting. In this article, the authors emphasize how these methods can be applied to general forms of probabilistic predictions and provide several SAS macros for computation of the desired statistics.

Medicare inpatient physician charges: an econometric analysis

To control Medicare physician payments, Congress in 1989 established volume performance standards (VPS) that tie future physician fee increases to the growth in expenditures per beneficiary. The VPS risk pool is nationwide, and many observers believe it is too large to affect behavior. VPS could be modified by defining a separate risk pool for inpatient physician services and placing each hospital medical staff at risk for those services. Using a national random sample of 500,000 Medicare admissions, we explore the determinants of medical staff charges and comment on the policy implications. Multivariate analysis shows that charges increase with case mix and bed size but, surprisingly, decrease with the level of teaching activity. The teaching result is explained by the substitution of residents for physicians in these hospitals.

Physician charges in the hospital. Exploring episodes of care for controlling volume growth

Medicare physician payments are growing rapidly. At least 40% of the annual growth is due to volume increases. Reforms passed in 1989 include volume performance standards that attempt to control volume by linking future physician fee increases to volume growth. There is concern that defining the entire nation as the risk pool will result in an unworkable volume performance standard. One way to improve incentives is to create a separate volume performance standard for in-hospital physician services, define bundles of services related to the hospital stay, and place the medical staff of the hospital at risk for volume growth. To forestall the unbundling of services outside the stay, windows could be defined around the stay. This study reports physician services during the stay and in windows around the stay. In so doing, the study creates the knowledge base necessary to design better volume control policies and judge among alternative window definitions. Using 1987 data, this study presents average physician charges by type of service during: 1) the hospital stay; and 2) 1-month windows before and after the stay. For all admissions, 85% of charges occur during the stay and 15% occur during the windows (windows for surgical admissions and medical admissions are 9% and 23%, respectively). Pre- and postwindows are roughly symmetrical and average charges per day gradually increase before the admission and decline after discharge. A small physician panel commented on the clinical appropriateness of the one month windows. The panel indicates that defining in-hospital episodes of physician care is feasible.

Gigantic osteoma of the mandible: report of a case

A case of a very large solitary osteoma of the right posterior mandible in a 22-year-old man is presented. The tumor was asymptomatic despite its location and large size. It was removed via an extraoral Risdon approach without complication. The importance of differentiating a large solitary osteoma from a parosteal osteogenic sarcoma is emphasized. Any patient presenting with a solitary osteoma also should be evaluated for Gardner's syndrome.

Frequency of medium-chain acyl-CoA dehydrogenase deficiency G-985 mutation in sudden infant death syndrome

A small percentage of apparent sudden infant death syndrome (SIDS) victims may have an unsuspected metabolic disorder. Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is a disorder of fatty acid oxidation that has been the most common such metabolic disorder found in series of SIDS victims. A single mutation in MCAD deficiency has been recently described (G-985) that accounts for approximately 90% of MCAD deficiency mutations. We studied the hypothesis that heterozygosity or homozygosity for this specific MCAD deficiency mutation might be associated with SIDS. DNA was extracted from the paraffin-embedded autopsy tissues of 67 victims of SIDS in Monroe County, NY who died between 1984 and 1989. Using the polymerase chain reaction/NcoI digestion method, we found no G-985 homozygotes and three (4.5%) G-985 heterozygotes. In 70 newborn controls, there were no G-985 homozygotes and one (1.4%) heterozygote. Although the frequency of G-985 heterozygotes was slightly greater than in our control group, it was not statistically different. We conclude that the specific MCAD deficiency mutation G-985 is not strongly associated with SIDS and that MCAD deficiency probably does not make a significant contribution to the etiology of SIDS.

Differences across sexual orientation on HIV risk behaviours in injecting drug users

Injecting drug users (IDUs) play a disproportionate role in the spread of HIV given their injecting and sexual contacts, and thereby act as conduits between these risk groups. We investigated differences in risk behaviour and HIV seroprevalence in a Sydney sample of 1,245 IDUs. Significant differences were observed across sexual orientation in HIV serostatus for males, with homosexual men having the highest HIV seroprevalence rate (35%), bisexual men intermediate (12%) and heterosexual men lowest (3%). Sexual HIV risk behaviours were lowest for homosexual men, intermediate for bisexual men, and highest for heterosexual men in the case of condom use: however, for numbers of partners, seroprevalence, and anal sex the trends were reversed. There were no differences across sexual orientation for either sex for injecting drug risk behaviours. Both male and female respondents reported having more than 50% of sexual contacts while under the influence of drugs. This study suggests that risk reduction in the sexual domain has not generalized to the injecting risk domain regardless of sexual orientation, and demonstrates that sexual risk behaviours in IDUs are lowest in homosexual, intermediate in bisexual, and highest in heterosexual IDU men.

An infant with trisomy 9 mosaicism presenting as a complete trisomy 9 by amniocentesis

We present a case in which amniocentesis performed at 33 weeks' gestation because of symmetrical intrauterine growth retardation and decreased amniotic fluid volume led to the prenatal diagnosis of a fetus with a karyotype of 47,XX,+9,t(1;20)(q42;p11.2) pat, i.e., with an extra chromosome 9 and a balanced translocation between chromosomes 1 and 20. At delivery, the baby showed clinical features of trisomy 9, yet chromosome analysis of the cord blood revealed no trisomy 9 cells, a finding confirmed by neonatal blood karyotyping. The balanced translocation was present in all cells. A skin biopsy confirmed trisomy 9 mosaicism with 10 per cent trisomy 9 cells. The baby died at 6 weeks and an autopsy was obtained. Chromosome analysis of different organs demonstrated different frequencies of the mosaicism of trisomy 9. The possible underlying mechanism for the discrepancy between the karyotype results by amniocentesis and those of other tissues is discussed.

Medicare hospital outpatient services and costs: implications for prospective payment

Medicare expenditures of hospital outpatient department (HOPD) services are growing rapidly, prompting congressional interest in a prospective payment system. In this article, the authors identify frequently provided services and examine service volume and charges in the HOPD. Relatively few services drive Medicare HOPD spending, and volume is dominated by visits, imaging and laboratory tests, whereas surgery accounts for a large proportion of charges. Hospital-level variations in charges, costs, case mix, and outliers are also explored. There is substantial variation in charges and costs across hospital types. However, after case-mix adjustment, all hospital types have average costs within 6 percent of the national average.

Phase II trial of high-dose cisplatin plus etoposide plus vinblastine in non-small-cell lung cancer. A Hoosier Oncology Group study

Fifty-one patients with advanced non-small-cell lung cancer were treated on a Hoosier Oncology Group protocol with an aggressive, high-dose cisplatin combination chemotherapy regimen. All patients had a Karnofsky performance status of 80% or higher and had no prior chemotherapy. The drug regimen consisted of cisplatin 30 mg/m2 days one through five, etoposide 40 mg/m2 days one through five, and vinblastine 5 mg/m2 day one. Therapy was given every three weeks for a total of three courses. Forty-five patients were evaluable for response and an objective response was seen in 15 patients (33%) with only one complete responder. The median duration of response was 16.5 weeks. The median survival for the entire group was 29.0 weeks. Toxicity was moderately severe with two treatment-related deaths (4%). Despite an aggressive chemotherapy regimen in a favorable patient population, there was no obvious evidence of a major therapeutic value.

Scapular fractures. Analysis of 113 cases

Scapular fractures have been the subject of study since Desault's treatise of 1805, but few large-scale studies have been completed with long-term follow-up evaluation of displaced scapular neck and spine fractures. This series of 148 fractures in 116 scapulae (113 patients) appears to be the largest ever reported and the only one with a follow-up study of a significant group (24 patients). Significant disability was found in patients with displaced scapular spine and neck fractures: (1) pain at rest in 50%-100%, (2) weakness with exertion in 40%-60%, and (3) pain with exertion in 20%-66%. Based on these findings, the indications for operative management should be expanded to include displaced scapular neck and spine fractures. Using extensile exposure through a posterior Judet incision, rigid internal fixation, and early motion, results in eight cases were excellent. All patients recovered at least 85 degrees of glenohumeral abduction, normal scapulothoracic motion, and none had resting pain, night pain, or pain with abduction. The minimum follow-up study period was 15 months.

Validation techniques for logistic regression models

This paper presents a comprehensive approach to the validation of logistic prediction models. It reviews measures of overall goodness-of-fit, and indices of calibration and refinement. Using a model-based approach developed by Cox, we adapt logistic regression diagnostic techniques for use in model validation. This allows identification of problematic predictor variables in the prediction model as well as influential observations in the validation data that adversely affect the fit of the model. In appropriate situations, recommendations are made for correction of models that provide poor fit.

Practice randomization and clinical research. The Indiana experience

Thoughtful preparation of a research laboratory is an early step in designing a program for scientific investigation. The Division of General Internal Medicine at Indiana University has maintained a "laboratory" for outpatient clinical investigation for more than 15 years. In this report, we describe the structure and function of the General Medicine Practice in the Regenstrief Health Center on the campus of the Indiana University School of Medicine in Indianapolis. Specifically, we discuss the ongoing random allocation of subjects, the local resources for data management and tracking of patients' use of clinical services, and how combining this information system into a randomized primary care system has fostered successful ventures in clinical investigation.

Randomized study of cisplatin dose intensity in poor-risk germ cell tumors: a Southeastern Cancer Study Group and Southwest Oncology Group protocol

Between 1984 and 1989, 159 patients presenting with advanced germ cell cancer were entered on a randomized clinical trial comparing the efficacy and toxicity of etoposide and bleomycin and either standard-dose cisplatin (20 mg/m2 daily for 5 days) or high-dose cisplatin (40 mg/m2 daily for 5 days). Of the 159 patients, 153 were assessable for toxicity and response. As expected, patients receiving the high-dose cisplatin regimen experienced significantly more neurotoxicity, ototoxicity, nausea and vomiting, and myelo-suppression. Four patients (3%) died related to therapy. Despite the toxicity encountered, dose intensity was maintained. Overall, 84% of patients in the high-dose arm received 80% or more of the projected dose of cisplatin, etoposide, and bleomycin; and 90% of patients on the standard-dose arm received 80% or more of the projected dose. Of the 76 eligible patients randomized to receive the high-dose cisplatin regimen, 52 (68%) became disease-free with chemotherapy alone or with subsequent resection of residual teratoma or cancer. Of the 77 patients randomized to the standard-dose arm, 56 (73%) became disease-free with chemotherapy alone or with surgery. Median follow-up is now 24 months. Eleven patients (three high-dose and eight standard-dose) relapsed from disease-free status. Overall, 74% of patients receiving the high-dose cisplatin regimen are alive, and 63% are continuously free of disease. Of the patients receiving the standard-dose cisplatin regimen, 74% are alive, and 61% are continuously free of disease. This randomized prospective trial in advanced germ cell cancer achieved dose intensity of the most active single agent in this disease. This dose intensity did not translate into an improved survival or cure. We conclude that dose escalation of cisplatin beyond standard doses results in excess toxicity with no accompanying therapeutic benefit.

Generalized variance component models for clustered categorical response variables

A generalized variance component model is proposed for the analysis of a categorical response variable with extra-multinomial variation. Categorical data obtained from research designs such as randomized multicenter clinical trials or complex sample surveys with clustering frequently exhibit extra-variation resulting from intracluster correlation. General correlation patterns are accounted for by utilizing a mixed-effects modelling approach, estimating the cluster variance components through the method of moments and modelling functions of the observed proportions through the use of estimating equations. A flexible set of assumptions characterizing the underlying covariance structure for the proportions can be accommodated. The importance of accounting for extra-variation when performing hypothesis tests is highlighted with an application to data from a multi-investigator clinical trial.

A herald bleed: a case of aortoesophageal fistula and a review of the literature

Survival in AEF is rare because the diagnosis of this uncommon entity is not always suspected, and few patients survive despite aggressive but often late intervention. We present this case to increase awareness of AEF, which although rare, does occur and should be suspected in any patient who presents with midthoracic pain or dysphagia and herald bleeding.

Sexually transmissible diseases in injecting drug users

Self-reported histories of sexually transmissible diseases (STDs) and HIV serostatus were investigated as part of a study of HIV risk behaviour in a sample of 1245 Syndey injecting drug users (IDUs) (mean age 27.5 years) both in and out of treatment. A high lifetime prevalence of STDs was reported in both men and women. For male IDUs, the lowest reported lifetime prevalence of STDs was in heterosexuals, with bisexuals intermediate and homosexuals reporting the highest prevalence. HIV seroprevalence followed the same pattern. For women, bisexuals had the highest reported STD history, heterosexual women were intermediate and homosexual women reported the lowest prevalence. Over one third of the bisexual women reported having been involved in prostitution. These data indicate that over one third of IDU men and over half of IDU women reported at least one STD in their lifetime. The high lifetime prevalence of STDs in IDUs indicates that this group is at increased risk of sexual transmission of HIV, given the importance of STDs as a cofactor. Reducing the prevalence of STDs in IDUs is a possible additional strategy to diminish the spread of HIV among IDUs and from them to non-IDU sexual contacts.