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PubMed2000

Empirical evidence on the demand for carve-outs in employment group mental health coverage.

BACKGROUND AND AIMS OF THE STUDY: The use of specialized behavioral health companies to manage mental/health benefits has become widespread in recent years. Recent studies have reported on the cost and utilization impacts of behavioral health carve-outs. Yet little previous research has examined the factors which lead employer-based health plans to adopt a carve-out strategy for mental health benefits. The examination of these factors is the main focus of our study. Our empirical analysis is also intended to explore several hypotheses (moral hazard, adverse selection, economies of scale and alternate utilization management strategies) that have recently been advanced to explain the popularity of carve-outs. METHODS: The data for this study are from a survey of employers who have long-term disability contracts with one large insurer. The analysis uses data from 248 employers who offer mental health benefits combined with local market information (e.g. health care price proxies, state tax rates etc), state regulations (mental health and substance abuse mandate and parity laws) and employee characteristics. Two different measures of carve-out use were used as dependent variables in the analysis: (1) the fraction of health plans offered by the employer that contained carve-out provisions and (2) a dichotomous indicator for those employers who included a carve-out arrangement in all the health plans they offered. RESULTS: Our results tended to support the general cost-control hypothesis that factors associated with higher use and/or costs of mental health services increase the demand for carve-outs. Our results gave less consistent support to the argument that carve-outs are demanded to control adverse selection, though only a few variables provided a direct test of this hypothesis. The role of economies of scale (i.e., group size) and the effectiveness of alternative strategies for managing moral hazard costs (i.e., HMOs) were confirmed by our results. DISCUSSION: We considered a number of different hypotheses concerning employers' demands for mental health carve-outs and found varying degrees of support for these hypotheses in our data. Our results tended to support the general cost-control hypothesis that factors associated with higher use and/or costs of mental health services increase the demand for carve-outs. LIMITATIONS: Our database includes a small number of relatively large employers and is not representative of employers nationally. Our selection criteria, concerning size and the requirement that some employees are covered by LTD insurance, probably resulted in a study sample that offers richer benefits than do employers nationally. Our employers also report a higher percentage of salaried employees relative to the national data. Another deficiency in the current study is the lack of detailed information on the socio-demographic and behavioral characteristics of covered employees. Finally, the cross-sectional nature of our analysis raises concerns about susceptibility of our findings to omitted variables bias. IMPLICATIONS FOR FURTHER RESEARCH: Research with more information on covered employee characteristics will allow for a stronger test of the general hypothesis that factors associated with a higher demand for services are also associated with a higher demand for carve-outs. Also, future analyses that capture the experience of states that have recently passed mandate and parity laws, and that use pooled data to control for omitted variables bias, will provide more definitive evidence on the relationship between these laws and carve-out demand.

Journal Article↗
PubMed2002

ELISA inhibition assay for the quantitation of antigenic protein in natural rubber latex.

Evaluating allergenicity of natural rubber latex (NRL) products is essential for the successful reduction of the consumer's exposure to potentially allergenic NRL proteins. We have developed an ELISA Inhibition method for the quantitation of extractable proteins from NRL products which has good sensitivity and specificity. The method utilizes rabbit anti-NRL protein serum as a detection mechanism. The source of NRL proteins for immunization and as a reference protein in the assay is ammoniated raw latex (AL). By comparison with the Western blot analysis of the rabbit sera, it appears that the ELISA detects most of the latex proteins present in extracts. To investigate, further, this assumption, we compared the ELISA Inhibition test with two other methods for total protein measurement. We also compared the values generated by the ELISA Inhibition test with other immunological methods for quantitation of antigenic and allergenic proteins. Comparisons were performed with 15 extracts from randomly selected surgical and examination gloves. The samples were coded separately for each test to insure the objectivity of evaluation. The antigenic protein values obtained by the ELISA Inhibition test correlated best with the HPLC amino acid analysis (correlation coefficient (cc) = 0.79) and with the LEAP assay (cc = 0.97). The antigenic protein levels obtained by the ELISA test were 3-10 times lower than those obtained by the HPLC analysis. A lesser correlation was observed with the Modified Lowry assay (cc = 0.45), which is likely due to chemical interference bias in the Lowry method. Our findings suggest that the antigenic proteins measured by the ELISA Inhibition test described here more closely represent the measure of the total protein content in the extracts. It is important to note that the relative values obtained by this method are lower than the values obtained by other total protein methods, possibly due to a large number of small peptides present in NRL products, that would only be measured by the chemical method.

Animals↗
PubMed2004

Hereditary nonpolyposis colorectal carcinoma (HNPCC) and HNPCC-like families: Problems in diagnosis, surveillance, and management.

BACKGROUND: To the authors' knowledge, hereditary nonpolyposis colorectal carcinoma (HNPCC) is the most commonly occurring hereditary disorder that predisposes to colorectal carcinoma (CRC), accounting for approximately 2-7% of all CRC cases diagnosed in the U.S each year. Its diagnosis is wholly dependent on a meticulously obtained family history of cancer of all anatomic sites, with particular attention to the pattern of cancer distribution within the family. METHODS: The objective of the current study was to illustrate various vexing problems that can deter the diagnosis of HNPCC and, ultimately, its management. This was an observational cohort study. Sixteen HNPCC and HNPCC-like families were selected from a large resource of highly extended HNPCC families. High-risk patients were selected from these HNPCC families. An ascertainment bias was imposed by the lack of a population-based data set. Personal interviews and questionnaires were used for data collection. RESULTS: There was an array of difficulties highlighted by limitations in compliance, lack of a clinical or molecular basis for an HNPCC diagnosis, ambiguous DNA findings, problems in genetic counseling, failure to meet Amsterdam or Bethesda criteria, small families, lack of medical and pathologic documentation, poor cooperation of family members and/or their physicians, cultural barriers, economic stress, frequent patient fear and anxiety, perception of insurance discrimination, and limited patient and/or physician knowledge regarding hereditary cancer. CONCLUSIONS: The diagnosis and management of HNPCC is predicated on physician knowledge of its phenotypic and genotypic heterogeneity, in concert with the multifaceted problems that impact on patient compliance.

Adult↗
PubMed1995

On the catch-up time method for analyzing cancer screening trials.

In randomized cancer screening trials, the ratio of the mortality rate for the screened group to that for the control group is typically not constant as a function of years from randomization. This is due to an initial lag effect, but also to a dilution effect that results from the accrual of comparable cases in both groups after the end of the screening period. In order to combat the potential loss of power when applying conventional analysis tools, specifically the logrank test, Aron and Prorok (International Journal of Epidemiology 15, 36-43), have advocated analyzing the mortality experience using only the subcohort of cases ascertained within a given time period. However, it is not clear how to select an appropriate case ascertainment point, since this will depend on aspects of the natural history of the disease process which are poorly identified. Aron and Prorok suggest choosing the case ascertainment point to be the point at which the cumulative number of cases in the control group first becomes equal to that in the intervention group, that is, the "catch-up time." In this paper, we undertake a thorough evaluation of the bias and power properties of the catch-up time method. We base our study on simulated data resembling the Health Insurance Plan of Greater New York study cohort. We consider several models for postdiagnosis survival under the null hypothesis of no screening effect on mortality, and under the alternative hypothesis of an effect of screening. We show that the catch-up method can yield tests with sizeable bias. In the absence of detailed knowledge about the underlying disease process, we suggest some adaptive tests that maintain nominal size but have more attractive power properties than the standard logrank test.

Adult↗
PubMed1995

Demographic differences in referral rates to neurologists of patients with suspected Parkinson's disease: implications for case-control study design.

Although patients with Parkinson's disease (PD) are often treated by neurologists, most are first diagnosed by a primary care physician. Epidemiologic studies which use PD cases from only neurology clinics may be subject to referral bias due to differential case selection in the referral process. To study this methodological issue, a historical cohort study of all outpatients with PD diagnosed by a non-neurologist from January 1, 1988 to June 1, 1992 at the Henry Ford Health System was conducted. This health system has specialty and primary care outpatient clinics located at the main facility in Detroit, Mich. and throughout the metropolitan area. The analysis included those who had at least one outpatient visit during the follow-up period from January 1, 1988 to June 30, 1993 (n = 588), of whom 183 (31.1%) were referred to a neurologist. The univariate analysis resulted in crude risk ratios for referral of 2.14 [95% confidence interval (CI) = 1.56-2.93] for age less than 70, 2.11 (95% CI = 1.57-2.84) for male sex, 1.64 (95% CI = 1.17-2.32) for nonwhite race, 2.48 (95% CI = 1.77-3.47) for private health insurance, 1.79 (95% CI = 1.32-2.43) for being married, 1.44 (95% CI = 1.08-1.92) for 10 or more health care visits per year and 2.27 (95% CI = 1.66-3.11) for having the initial visit for PD at the main Detroit clinic. In a Cox proportional hazards model which included all study variables, race and marital status were no longer statistically significant (p < 0.05), and no risk estimates were greater than 2.0. In summary, patients referred to neurologists in this study were more likely younger, male, to have private health insurance, frequent users of health care and to use hospital-based clinics for their primary health care. We suggest that future case-control studies of PD avoid potential referral bias by not using a study population comprised solely of patients referred to a neurology clinic or design studies which can estimate the potential effect of this bias.

Age Distribution↗
PubMed1993

Social justice, federal paternalism, and feminism: breast implants in the cultural context of female beauty.

In April 1992 the Food and Drug Administration (FDA) announced it was restricting the availability of silicone gel-filled breast implants to women enrolled in clinical trials. All candidates for breast reconstruction, but only a "very limited" number of augmentation candidates, would have access to the implants. This policy has been criticized as paternalistic, sexist, and unjustified by scientific data. I examine these charges and conclude that controversy surrounding the scientific data weakens the FDA's paternalistic mandate and that its policy of treating reconstruction and augmentation candidates differently results in increased social injustice and perpetuates cultural biases concerning female beauty and women's rights to control their bodies. I also argue that these cultural biases shape women's subjective experience of their physical selves and should not, contrary to some feminist arguments, be viewed as precluding their giving informed consent to breast surgery.

Breast Implants↗
PubMed1995

Older women's health: 'taking the pulse' reveals gender gap in medical care.

In the United States, for every 100 men age 65 and older, there are 147 women, a ratio that has social and medical consequences. Five panelists "take the pulse" of older women's health in general and in the offices of primary care physicians in particular. They assess the status of medical education and the need to include older women in research and drug trials, issues of gender bias in health insurance and quality of treatment, ways to improve the use of preventive health services--such as mammography and Pap smears--by older women, and the role of office physicians in identifying and helping victims of domestic violence.

Aged↗
PubMed2001

A short course of induction chemotherapy followed by two cycles of high-dose chemotherapy with stem cell rescue for chemotherapy naive metastatic breast cancer.

A single cycle of high-dose chemotherapy with stem cell support (HDC) in women with responsive metastatic breast cancer (BC) consistently achieves over 50% complete and near complete response (CR/nCR). This significant cytoreduction results in a median event-free survival (EFS) of 8 months, and approximately 20% 3-year and 16% 5-year EFS in selected patients. To improve long-term outcomes, new strategies to treat minimal residual tumor burden are needed. Increased total dose delivered can be achieved with two cycles of HDC. Critical design issues include shortening induction chemotherapy to avoid development of drug resistance and the use of different agents for each HDC cycle. We have determined the maximum tolerated dose (MTD) for paclitaxel combined with high-dose melphalan in the context of a double transplant and explored the impact of a short induction phase. Between June 1994 and August 1996, we enrolled 32 women with metastatic BC on to this phase I double transplant trial. Induction consisted of doxorubicin 30 mg/m2/day days 1-3 given for 2 cycles every 14 days with G-CSF 5 microg/kg s.c. days 4-12. Stem cell collection was performed by leukapheresis in each cycle when the WBC recovered to above 1000/microl. Patients with stable disease or better response to induction were eligible to proceed with HDC. HDC regimen I (TxM) included paclitaxel with dose escalation from 0 to 300 mg/m2 given on day 1 and melphalan 180 mg/m2 in two divided doses given on day 3. HDC regimen II was CTCb (cyclophosphamide 6 g/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 total doses) delivered by 96-h continuous infusion. At the first dose level of 150 mg/m2 paclitaxel by 3 h infusion, four of five patients developed dose-limiting toxicity consisting of diffuse skin erythema and capillary leak syndrome. Only two of these five completed the second transplant. Subsequently, paclitaxel was delivered by 24-h continuous infusion together with 96 h of dexamethasone and histamine receptor blockade. This particular toxicity was not observed again. No toxic deaths occurred and dose-limiting toxicity was not encountered. Three patients were removed from study prior to transplant: one for insurance refusal and two for disease progression. All others completed both cycles of transplant. Complete and near complete response (CR/nCR) after completion of therapy was achieved in 23 (72%) of 32 patients. The median EFS is 26 months. The median overall survival has not yet been reached. At a median follow-up of 58 months, EFS and overall survival are 41% and 53%, respectively. This double transplant approach is feasible, safe, and tolerable. Treatment duration is only 14 weeks and eliminates lengthy induction chemotherapy. The observed event-free and overall survivals are promising and are better than expected following a single transplant. Whilst selection biases may in part contribute to this effect, a much larger phase II double transplant trial is warranted in preparation for a potential randomized comparison of standard therapy vs single vs double transplant.

Adult↗
PubMed1993

The call for help after an injury road accident.

How soon will the authorities receive a call for help after an injury road accident? In urban Missouri 70% of the calls were received in less than five minutes. But in rural Missouri only 34% of the calls came in that quickly. These figures are based on a merge of police and emergency medical services accident data in which the earlier of the two notifications is selected as the time of first call. Police estimates of accident time are used here to calculate the interval from accident to the first call. The police estimates lack precision. This is shown by the high percentage of rounded numbers. As averages, however, these estimates show little evidence of bias. In urban areas, delays are related to time of day and type of road system, while in rural areas, remoteness of location is an added factor. Difficulty in finding a telephone quickly in certain road environments can be a problem. However, installing more stationary telephones along roads may be inefficient. Large areas would have to be covered to insure even a modest reduction in delays. More thought, therefore, should be given to the use of innovative vehicle-to-satellite technologies.

Accidents, Traffic↗
PubMed2006

Overcoming bias in estimating the volume-outcome relationship.

OBJECTIVE: To examine the effect of hospital volume on 30-day mortality for patients with congestive heart failure (CHF) using administrative and clinical data in conventional regression and instrumental variables (IV) estimation models. DATA SOURCES: The primary data consisted of longitudinal information on comorbid conditions, vital signs, clinical status, and laboratory test results for 21,555 Medicare-insured patients aged 65 years and older hospitalized for CHF in northeast Ohio in 1991-1997. STUDY DESIGN: The patient was the primary unit of analysis. We fit a linear probability model to the data to assess the effects of hospital volume on patient mortality within 30 days of admission. Both administrative and clinical data elements were included for risk adjustment. Linear distances between patients and hospitals were used to construct the instrument, which was then used to assess the endogeneity of hospital volume. PRINCIPAL FINDINGS: When only administrative data elements were included in the risk adjustment model, the estimated volume-outcome effect was statistically significant (p=.029) but small in magnitude. The estimate was markedly attenuated in magnitude and statistical significance when clinical data were added to the model as risk adjusters (p=.39). IV estimation shifted the estimate in a direction consistent with selective referral, but we were unable to reject the consistency of the linear probability estimates. CONCLUSIONS: Use of only administrative data for volume-outcomes research may generate spurious findings. The IV analysis further suggests that conventional estimates of the volume-outcome relationship may be contaminated by selective referral effects. Taken together, our results suggest that efforts to concentrate hospital-based CHF care in high-volume hospitals may not reduce mortality among elderly patients.

Aged↗
PubMed2002

Quasi-experimental longitudinal designs to evaluate drug benefit policy changes with low policy compliance.

A causal relation between drug benefit policy change and the increase in adverse outcomes can be tested by comparing the experience of a group of patients affected by the policy vs. the (counterfactual) experience of the same patients if the policy had not been implemented. Because counterfactual experiences cannot be observed, it must be assumed that the counterfactual is correctly described by extrapolating from the same population's previous experience. The null hypothesis of no policy effect can be empirically tested using quasi-experimental longitudinal designs with repeated measures. If compliance to a policy is low, results may be biased towards the null, but a subgroup analysis of compliers may be biased by nonignorable treatment selection. Using the example of reference drug pricing in British Columbia we discuss assumptions for causal interpretations of such analyses, and provide supplementary analyses to assess and improve the validity of findings. Results from nonrandomized comparisons of subgroups defined by their compliance to a policy change should generally be interpreted cautiously, and several biases should be explored.

Attitude of Health Personnel↗
PubMed1992

The welfare state, class, and gender.

If we compare the welfare state countries with others, from the point of view of both health and health services, the crisis concerns primarily the second group of countries. Nevertheless, difficulties arise also for welfare state policies. The problem is how to respond to neoconservative attacks on social and health rights, and how to change the bureaucratic and medicalized bias of the welfare state. The "golden era" of social insurance and health services, conceived as free access to funds to cope with all the growing needs of the population, is over. Limitations, controls, and priorities have to be established. In Italy and similar countries, the tendency is toward restricting health care for those who have greater needs, cutting funds for prevention, and creating greater inequalities. It is clear that the state must intervene to reduce social inequalities, but at the same time some existing differences (sexual, cultural, ethnic) have an intrinsic value that must be recognized. A policy of free-choice welfare is useful, and has nothing to do with the selective measures that are being introduced. Moreover, a key point has become the relationship between class and gender. The working class continues to be exploited, but new phenomena arise, connected with production and social reproduction and not limited to this sphere. It is true that gender includes social classes, but no social class may represent both sexes, or different ethnic groups, or gender itself.

Female↗
PubMed1994

Gains in dental care use not shared by minority elders.

Americans have steadily increased their reported use of dental services over the past 30 years. Persons aged 65 years and older have made the greatest gains, from 16 percent in 1957-58 to 43 percent in 1989. This article reviews national data on reported use of dental care over the past three decades, focusing on differences in rates of utilization on the basis of age, race, and national origin. In addition, differences in sample selection, definitions of race and national origin, and data collection methodology were reviewed to identify systematic sources of bias in comparing the data. Findings indicate that reported dental care use among minority elders has not increased parallel with elders of all races and national origins. In 1957-59, 17 percent of white elders versus 9 percent of nonwhite elders had seen a dentist within the past year. By 1989 percentages had improved to 45 percent of whites, but only 22 percent of blacks and 40 percent of Hispanics. In addition, reporting and recording race and national origin varied considerably during the three decades, hampering comparisons over time. Finally, published national data on usual correlates of dental care use (dentition status, insurance, age, income, and education) are inadequate to explain the causes of these discrepancies. More research is needed to identify barriers to use of dental care by all Americans, particularly those of African and Hispanic descent.(ABSTRACT TRUNCATED AT 250 WORDS)

Black or African American↗
PubMed1999

Association between health insurance and antibiotics prescribing in four counties in rural China.

A cross-sectional study was carried out at county, township and village health care facilities in four counties in rural China in order to describe and compare the effects of health financing systems on antibiotic prescribing in outpatient care. A total of 1232 outpatients at the health care facilities was selected by multi-stage random sampling and were interviewed over 2 weeks. The results showed that health financing systems appeared to influence antibiotic prescribing in outpatient care, both in terms of frequency and of the types prescribed. The insured group had lower prescribing of antibiotics at township and village health care facilities, and for respiratory tract infections, but had higher prescribing of newer antibiotics at county and village health care facilities, for respiratory tract and g-i infections. Because there was a high patient compliance rate (94.3%) in this study the prescribing of antibiotics (supply side behavior) reflected the use of antibiotics (demand side behavior) to a great extent. Thus the results imply that antibiotics prescribing and using might be biased by the patient's health financing systems and antibiotic prescribing was the result of the interaction between physicians and patients.

Anti-Bacterial Agents↗
PubMed2000

A case-control study for evaluating lung cancer screening in Japan.

BACKGROUND: Lung cancer screening using chest X-ray examination and sputum cytology was introduced by the Japanese government in 1987. However, there was no direct evidence of the benefit from lung cancer screening in terms of reduction of mortality at that time. METHODS: A case-control study was conducted using the data from 50 areas in which population-based lung cancer screening programs had been conducted for several years. Case series consisted of 273 deceased lung cancer cases, and 1269 control patients were collected from those who were alive at the time of diagnosis of the corresponding case: These were matched by gender, age, smoking status, and type of health insurance. Screening histories, which were obtained from the list of screenees, were compared between cases and matched controls for the identical calendar period before the time of diagnosis of the case. RESULTS: The odds ratio for dying from lung cancer for those who were screened within 12 months compared with those who were not screened was 0.72 (95% confidence interval, 0.50-1.03). When divided by gender, the odds ratio was significantly decreased in females. CONCLUSIONS: The authors interpreted these data to indicate that there is a small positive effect of lung cancer screening in terms of reducing mortality due to lung cancer. However, this small effect cannot be evaluated adequately by observational studies, such as case- control studies, because of the self-selection bias. Discussion is needed to determine the resources that should be allocated to this issue for developing an effective strategy for lung cancer control.

Adult↗
PubMed2006

Increased risk of developing stroke among patients with bipolar disorder after an acute mood episode: a six-year follow-up study.

BACKGROUND: Despite cerebrovascular diseases having been reported as one of the major causes of death among patients with bipolar disorder, there is scant information on the risk of stroke among this patient population. This study estimated the relative risk of developing stroke among patients with bipolar disorder in 6 years following hospitalization for an acute mood episode compared with patients undergoing appendectomy. METHODS: Two study cohorts were identified from the Taiwan National Health Insurance Research Database for the year 1998: patients hospitalized with bipolar disorder, and patients undergoing an appendectomy. Follow-up was undertaken to determine whether sampled patients had utilized emergency medical services for the management of any type of stroke in the period 1998-2003. RESULTS: Stroke occurred among 2.97% of patients with bipolar disorder and 1.50% of patients undergoing appendectomy between 1998 and 2003. The adjusted odds ratio of developing stroke, by cohort, shows that after adjusting for demographic characteristics, comorbid medical disorder, and substance or alcohol dependence, patients with bipolar disorder were more likely to develop stroke (OR=2.05; 95% CI=1.73-3.54). LIMITATIONS: The validity of diagnoses, lacking of information on smoking, body mass index, and socioeconomic status, and possible selection bias might compromise the findings. CONCLUSIONS: During the six-year follow-up period, the likelihood of developing stroke was twice as great amongst patients with bipolar disorder as patients undergoing an appendectomy. A requirement exists for the initiation of research providing an understanding of the pathophysiological mechanisms of the association between stroke and bipolar disorder.

Acute Disease↗
PubMed2002

Atrial fibrillation after coronary surgery: comparison between different health care systems.

AIMS: No studies have evaluated the influence of management strategies in different health insurance environments on atrial fibrillation (AF). This observational study compared the incidence of and treatment strategies for postoperative AF after primary coronary bypass surgery. METHODS AND RESULTS: One insurance and one public funded location was compared: University of Michigan Health Center (USA, n=272) and Tampere University Hospital (Finland, n=314). USA patients had more co-morbidities and were treated more aggressively after acute myocardial infarction. More Finns were on beta-blockers both preoperatively (93 vs. 68%, P<0.001) and postoperatively (97 vs. 66%, P<0.001). However, AF was more frequent among Finns (38 vs. 29%, P=0.037) and present on 4.6% of cases when transferred postoperatively. No USA patients had AF at time of discharge. Mean length of stay was 8.6 days at USA, and not affected by AF. The incidence of in-hospital death, strokes and multiorgan failures was similar. Multivariable analysis, adjusted for site and selection biases (propensity analysis) revealed increasing age [OR=1.063 (1.042, 1.084), P<0.0001] and use of radial arteries [OR=2.175 (1.071, 4.417), P=0.032) to be independent predictors to the incidence of postoperative AF. CONCLUSIONS: We found several major differences in patient selection and treatment strategies among primary coronary bypass patients managed in the two institutions. Despite the marked practice variation, the incidence of postoperative AF was rather similar. Despite routine use of beta-blockers, AF occurred in 29-38% of patients. However, the length of stay was not particularly affected by postoperative AF.

Adrenergic beta-Antagonists↗
PubMed1995

The effect of US children's access to care on medical attention for injuries.

This analysis examined the effect of access to care on nonfatal medically attended injury rates for US children in 1988. Rates of medically attended injury were about the same for children with health insurance and Medicaid, after adjustment for other characteristics. However, lack of medical care coverage (health insurance or Medicaid) had the effect of decreasing the rates of both total and serious medically attended injury compared with the rates for children with coverage. For children without coverage, as many as 30% of total injuries and 40% of serious injuries may not have been attended in 1988.

Adolescent↗