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C L Bennett

Publications and source records attributed to C L Bennett.

At least 145 records · Page 8Linked to original sources
PubMed1995

Free-riding and the prisoner's dilemma: problems in funding economic analyses of phase III cancer clinical trials.

PURPOSE: Both economic and clinical data on new agents are important to policy-makers who approve pharmaceuticals for widespread use. Randomized clinical trials have been used to evaluate both clinical results and total medical costs associated with new agents. With new expensive pharmaceutical agents, early assessments of economic benefit have taken on greater importance to physicians and patients. Who should provide financial support to these integrated economic and clinical analyses in clinical trials? Here we describe issues that hinder funding of economic analyses and propose potential support mechanisms. RESULTS: The Cancer and Leukemia Group B (CALGB), a large, national cooperative group of academic and community hospitals in the United States, designed a non-small-cell lung cancer (NSCLC) treatment trial to compare two widely used supportive care regimens that varied 20-fold in cost. One important objective of this trial was to compare the cost-effectiveness of the two regimens. While funding for the clinical trial was supported by grants from the National Cancer Institute and the pharmaceutical companies involved in the trial, no specific funding agency was willing and/or able to provide financial support for the economic analyses. After 2 years of planning, the clinical trial was retracted when the funding for the economic analyses could not be secured. The prisoner's dilemma, individual reluctance to support a common social good, explains the lack of funding. CONCLUSION: Economic theory predicts difficulties in evaluating cost-effectiveness of new pharmaceuticals and reluctance to support economic analyses of clinical trials. Economic analyses will require new sources of funds that will not take scarce resources from clinical trials groups. Options for funding include a new federal agency, coordinated work by existing agencies, or academic centers for economic analysis.

Carcinoma, Non-Small-Cell Lung↗
PubMed1995

Economic analysis during phase III clinical trials: who, what, when, where, and why?

With the recent surge in interest in health care reform and the growth of managed care organizations, the cost of care has become a major determinant of the types and intensity of therapy that patients receive. if data on the cost effectiveness of new treatments are not collected during phase III trials, diffusion of new technologies may be restricted by managed care companies and insurers. We can collect the data needed to evaluate the costs and cost effectiveness of new therapies, as well as quality of life data, in phase III trials. But to collect these data effectively, many methodologic questions must be answered. For example, who needs to be involved in an economic analysis of a medical treatment; what data should be collected, when, and from whom; what data collection sources should be used; and how should the data be collected and validated? To embark on economic studies of new therapies, it is imperative that these issues be addressed early, during the design phase of a trial, and a course of action determined.

Clinical Trials, Phase III as Topic↗
PubMed1994

Economic analyses of clinical trials in cancer: are they helpful to policy makers?

Although clinical trials are being used to evaluate economic outcomes of new agents, there are methodological problems. Decisions based on these analyses may lead to inefficient use of medical resources. Randomized clinical trials provide important information on the efficacy of new pharmaceutical agents for cancer patients. Policy makers are likely to require both economic and clinical data in order to approve pharmaceuticals for widespread use. Clinical trials provide an opportunity to evaluate economic outcomes for new agents. However, the interpretation of economic analyses of clinical trials raises issues related to perspective of the investigators, study design, collection of data on resource utilization, and generalizability of data to other settings. In this paper, we review these issues and illustrate problems associated with analyses of economic data from a recent phase III trial of hematopoietic growth factors. Clinical results were similar in both Paris and New York in this phase III trial. However, economic results differed markedly between the hospital in Paris and the hospital in New York. While significant savings in terms of fewer days in the hospital and fewer laboratory tests and radiographs for the granulocyte-macrophage colony-stimulating factor (GM-CSF) patients were noted at the New York hospital, resource savings were not identified at the hospital in France. Caution must be used when reimbursement policies are based on economic analyses of clinical trials. Policy decisions must be based on studies that are carefully conducted, analyzed, and interpreted from both a clinical and an economic perspective.

Anti-Bacterial Agents↗
PubMed1994

Frequencies of variants of candidate genes in different age groups of hypertensives.

1. In severe, familial hypertension, we have reported that the proportion of patients homozygous for the deletion allele of an insertion/deletion polymorphism of the angiotensin I-converting enzyme gene is markedly decreased in older age groups, suggesting that this genotype is associated with increased risk of premature death. The aim of the present study was to examine the relationship with age, of variants of other genes that encode proteins having an influence on the cardiovascular system. 2. Genotypes of 13 different variants at 12 relevant genetic loci were determined by either Southern blotting, followed by hybridization probing, or polymerase chain reaction techniques, as appropriate, using genomic DNA extracted from blood leukocytes. Genotype numbers were then assigned to the age categories of < 50, 50-59 and > or = 60 years. 3. Polymorphisms at the atrial natriuretic factor, antithrombin III, renin, angiotensinogen, neuropeptide-Y Y1 receptor, insulin, alpha 2-adrenoceptor, beta 1-adrenoceptor, growth hormone, low density lipoprotein receptor, insulin receptor and renal kallikrein gene loci were found to display similar allele frequencies in each age group of hypertensives, as well as in normotensive controls. 4. In conclusion, we were unable to detect any difference with age for a range of variants of genes whose products have cardiovascular significance, suggesting that, like most polymorphisms, they carry no selective survival advantage or disadvantage in the hypertensive and normotensive population groups studied.

Age Factors↗
PubMed1994

Differences in the perceptions of HIV risk amongst dental care providers in Western Australian clinics.

This paper examines the perceived risk of occupationally contracting HIV among dental care providers. This examination is based upon responses to a mailed questionnaire from all registered dentists (76 per cent response rate, n = 550) and dental therapists (63 per cent response rate, n = 208) in Western Australia during 1992. Results indicate that: 1) dental care providers who perceive a high risk of occupationally contracting HIV report a more conservative, cautious approach to HIV infection than do providers who perceive less risk of contracting the virus; 2) dental therapists are more likely than dentists to report a higher degree of perceived risk of occupationally contracting HIV; and 3) dentists are more likely than dental therapists to perceive compliance with universal precaution guidelines in dental practices in which they work. Reasons are presented for a suspicion that both sets of perceptions may be exaggerated. The need to educate dental therapists on the realistic risks of occupationally contracting HIV and to educate dentists on the value of compliance (and of appearing to comply) with universal precaution guidelines in order to help reduce undue stress and hindrances in the provision of safe and effective dental care in this era of AIDS concludes this paper.

Acquired Immunodeficiency Syndrome↗
PubMed1994

A rapid preadmission method for predicting inpatient course of disease for patients with HIV-related Pneumocystis carinii pneumonia.

Pneumocystis carinii pneumonia (PCP) has been the most common reason for hospitalization and the most common cause of death for persons with HIV infection. Hospital mortality rates for PCP range from 10 to 60%. Studies that evaluate differences in hospital mortality rates must control for differences in patient severity of illness. We developed a simple staging system for categorizing severity of illness in patients with PCP. We analyzed the relation between clinical factors and in-hospital mortality for 576 hospitalized patients with HIV-related PCP treated at 56 hospitals for the years 1987 to 1990. Four stages of PCP could be identified based on three routinely measured clinical variables: alveolar-arterial oxygen difference, total lymphocyte count, and body mass index. The mortality rate increased by stage: 1% for Stage 1, 8% for Stage 2, 23% for Stage 3, and 48% for Stage 4. The four-stage severity system compared well with previous models developed for AIDS and for PCP, and is easier to use in clinical practice. Our staging system identifies patients with a high and low risk of in-hospital death upon admission. Physicians may benefit from consideration of PCP stage in deciding on management strategies. In addition, researchers involved in clinical trials of new agents for PCP might consider stratification by PCP stage in order to define homogenous groups.

AIDS-Related Opportunistic Infections↗
PubMed1994

Economic analysis in phase III clinical cancer trials.

Randomized phase III clinical trials provide important information on the efficacy of new pharmaceutical agents for cancer patients. Policy makers are showing increased interest in both economic and clinical data on new agents in order to approve pharmaceuticals for widespread use, and clinical trials have been viewed as the proper setting to evaluate these outcomes for new agents. With the recent approval of new pharmaceutical agents that have high costs, early assessments of economic benefit have taken on larger importance to physicians and patients. The integration of economic and clinical analysis in phase III clinical trials raises methodological and practical issues related to study design, collection of data on resource utilization, and generalizability of data to other settings. In this paper, we review these issues and discuss their relationship to clinical trials for new pharmaceutical products.

Clinical Trials, Phase III as Topic↗
PubMed1993

Cross-sectional analysis of Met235-->Thr variant of angiotensinogen gene in severe, familial hypertension.

A recent cross-sectional study of HTs in Salt Lake City and Paris has reported a significant association of a T704-->C (Met235-->Thr) variant in exon 2 of the angiotensinogen gene (AGT) with essential hypertension (HT). The present study used a new, direct PCR technique to detect this variant in 92 Caucasians with severe hypertension (HT) and two HT parents and 94 normotensive (NT) controls. Although frequency of the variant in HTs (0.42) was higher than in NTs (0.39), the difference was not significant (chi 2 = 0.24; P = 0.63). Plasma angiotensinogen showed a weak, nonsignificant relationship with AGT genotype in females and no genotypic relationship was apparent for blood pressure. Thus, if the Met235-->Thr variant of AGT is involved in essential HT, then its contribution may be, at best, much weaker in other HT groups.

Alleles↗
PubMed1993

Scientific results from the Cosmic Background Explorer (COBE).

The National Aeronautics and Space Administration (NASA) has flown the COBE satellite to observe the Big Bang and the subsequent formation of galaxies and large-scale structure. Data from the Far-Infrared Absolute Spectrophotometer (FIRAS) show that the spectrum of the cosmic microwave background is that of a black body of temperature T = 2.73 +/- 0.06 K, with no deviation from a black-body spectrum greater than 0.25% of the peak brightness. The data from the Differential Microwave Radiometers (DMR) show statistically significant cosmic microwave background anisotropy, consistent with a scale-invariant primordial density fluctuation spectrum. Measurements from the Diffuse Infrared Background Experiment (DIRBE) provide new conservative upper limits to the cosmic infrared background. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the cosmic infrared background limits.

Journal Article↗
PubMed1993

Does experience improve hospital performance in treating patients with AIDS?

This paper examines how experience affects hospital performance in treating patients with AIDS. The most common life-threatening medical complication of AIDS is Pneumocystis carinii pneumonia (PCP). Studies of patients with PCP demonstrate that patients who received care at hospitals that were more experienced with AIDS had lower immediate mortality. These higher volume medical facilities did not use more resources but used resources more efficiently and provided better medical care. Better outcomes for experienced providers suggest three policy implications for improving quality of patient care: (1) create regionalized centers where large numbers of patients with a particular illness are treated; (2) encourage low volume providers to rapidly increase their experience; or (3) establish targeted educational programs for low volume providers. Historical review of experience with other medical problems such as tuberculosis indicate that one policy option, creating regional medical centers, did not have the desired effect of better patient outcomes. These facts support policies to provide targeted educational programs and opportunities for low volume facilities to rapidly increase their familiarity with AIDS. Outcomes could be improved by such policies.

AIDS-Related Opportunistic Infections↗
PubMed1993

Improved outcomes in intensive care units for AIDS-related Pneumocystis carinii pneumonia: 1987-1991.

Respiratory failure due to Pneumocystis carinii pneumonia (PCP) is the most common complication requiring an intensive care unit (ICU) for persons with AIDS. In this study, we evaluated patterns of ICU use for ICU patients with first-episode PCP in 15 Veterans Administration Medical Centers from 1987 to 1991. Twelve percent of all patients with PCP received care in the ICU. The survival rates improved steadily during these years. Although there was little variation in the relative frequency of ICU use, the effectiveness of ICU use appeared to improve over time. In the more recent years, relatively more survivors and relatively fewer nonsurvivors received care in an ICU. Changes in medical practice such as adjunctive use of steroids for severe cases of PCP and more effective use of scarce resources may account for the improved survival rates for patients with PCP who are treated in an ICU.

AIDS-Related Opportunistic Infections↗
PubMed1993

Quality of life and health service use among HIV-infected patients with chronic diarrhea.

Health-related quality of life and the utilization of health resources are important components of the evaluation of patient outcome in HIV infection because medical problems are often progressive and debilitating, and treatment is palliative. We evaluated quality-of-life measures and resource utilization of patients with AIDS and/or CD4 lymphocytes < 200 who had symptoms of chronic diarrhea and compared them with similar patients with AIDS and/or CD4 lymphocytes < 200 without diarrheal symptoms. Annual charges were 50% higher for patients with chronic diarrhea ($24,567 versus $14,471 for the comparison group, p < 0.01). Higher charges for the patients with diarrhea were a result of more physician visits and diagnostic testing. Quality-of-life scores were poor for all patients, but deterioration over the year in role functioning (social activity, daily living, energy, cognition) and general health was clearly evident (p < 0.01) for the patients with chronic diarrhea. These patients also suffered significant work loss and reported greater need for assistance in the home. These data suggest that HIV-infected patients with diarrhea experience marked decreases in quality of life and that care for patients with chronic diarrhea is costly. Relatively little attention has been paid to this debilitating syndrome, and current treatment options rarely provide permanent relief. Research and innovation in this area are needed; an estimated 25-50% of HIV-positive individuals suffer from this symptom complex.

Adult↗
PubMed1993

Differences between men and women with HIV-related Pneumocystis carinii pneumonia: experience from 3,070 cases in New York City in 1987.

Although women make up the fastest growing group of persons with AIDS, studies of human immunodeficiency virus (HIV)-infected persons reported to date have included predominantly or exclusively men. We evaluated sex differences in sociodemographic characteristics, hospital characteristics, in-hospital resource use, and short-term mortality rates for 2,526 men and 544 women admitted for their first-episode of HIV-related Pneumocystis carinii pneumonia (PCP) in New York City in 1987. Compared with men, women were significantly less likely to be white (81% vs. 54%, p < or = 0.001) or have private health insurance (80% vs. 58%, p < or = 0.001), and more likely to be admitted through an emergency room (79% vs. 71%, p < or = 0.001) and receive care at hospitals that had less experience treating PCP (p < or = 0.001). Women were more likely than men to die in the hospital [33% vs. 24%; crude odds ratio = 1.56, confidence interval (CI) = 1.28-1.91, p < or = 0.001]. In a logistic regression model, the risk of death in the hospital was associated with age 60-65 years [adjusted odds ratio (AOR) = 4.19, CI = 2.13-8.21], not having private health insurance (AOR = 1.37, CI = 1.08-1.75), admission through the emergency room (AOR = 1.54, CI = 1.21-1.96), and receiving care at hospitals with less experience treating PCP (AOR = 1.63, CI = 1.15-2.30), but women were not significantly more likely to die in the hospital than men (AOR = 1.18, CI = 0.93-1.50). Poorer access to medical care as well as higher use of hospitals with less experience treating AIDS may account for the difference in mortality rates observed in women with HIV-related PCP.

AIDS-Related Opportunistic Infections↗
PubMed1992

Granulocyte-macrophage colony-stimulating factor (GM-CSF) as adjunct therapy in relapsed Hodgkin disease.

OBJECTIVE: To determine the clinical and economic effects of granulocyte macrophage colony-stimulating factor (GM-CSF) as adjunct therapy in relapsed or refractory Hodgkin disease. DESIGN: A randomized, double-blind, phase III clinical trial. SETTING: A tertiary referral center. PATIENTS: Twenty-four patients (twelve of whom were controls) treated with high-dose chemotherapy and autologous bone marrow transplantation. MAIN RESULTS: The 12 patients treated with GM-CSF, when compared with placebo recipients, had shorter periods of neutropenia (median duration of an absolute neutrophil count of less than 1000 cells/mm3, 16 days compared with 27 days; P = 0.02), shorter periods of platelet-transfusion dependency (median duration, 13.5 days compared with 21 days; P = 0.03), and shorter hospitalizations (median hospital stay, 32 days compared with 40.5 days; P = 0.004). Other clinical outcomes, such as frequency and severity of toxicities, development of pneumonia or infection, in-hospital death, and response rate were similar in the two groups. Actuarial long-term disease-free survival was 64% for patients treated with GM-CSF and 58% for patients who received placebo after 32 months of follow-up (P = 0.15). The group treated with GM-CSF had lower total charges after infusion of autologous marrow than the placebo group (median in-hospital charges, $39,800 compared with $62,500; P = 0.005) because of lower post-infusion charges for room and board, antibiotic therapy, transfusions, laboratory tests, and physical therapy visits. CONCLUSIONS: Administration of GM-CSF was associated with acceleration of myeloid and platelet recovery and was cost effective in the treatment of patients with relapsed Hodgkin disease who received intensive chemotherapy.

Actuarial Analysis↗
PubMed1992

Health care use by human immunodeficiency virus-infected students at a California student health service.

We report characteristics of 16 college students with human immunodeficiency virus (HIV) infection but without the acquired immunodeficiency syndrome who received care at a student health center at a major university in California. Sociodemographic and clinical data and medical expenditures were obtained retrospectively from medical charts and computerized billing records. All 16 students were men who had sex with men, and 3 had also used intravenous drugs. Dermatologic conditions, upper respiratory tract infections, gastrointestinal conditions, anemia, lymphadenopathy, sexually transmitted diseases, and ophthalmologic conditions were more frequent among HIV-infected students than among the general student population using the health center. On average, HIV-infected students visited the student health service about 3 times more often and incurred charges about 10 times higher than the general population of students visiting the health center. Student health centers, which have been at the forefront of developing strategies for HIV prevention, education, and counseling, must also develop treatment programs for HIV-infected students.

Adult↗
PubMed1992

Relation between hospital experience and in-hospital mortality for patients with AIDS-related Pneumocystis carinii pneumonia: experience from 3,126 cases in New York City in 1987.

There is marked debate about whether outcomes of care, particularly mortality, vary as a function of hospital and physician experience with a disease. This issue is especially important with respect to AIDS because greater than 200,000 individuals have now been diagnosed with this disease. We analyzed discharge data for 3,126 persons with AIDS who had Pneumocystis carinii pneumonia and who were treated at one of 73 New York City hospitals in 1987. In-hospital mortality was 25%. Factors associated with higher chances of short-term death were older age, being black, not having private health insurance, and being severely ill. A logistic regression model indicated that after controlling for differences in patient and hospital characteristics, the chances of death decreased when care was given at hospitals with higher caseloads of patients with Pneumocystis carinii pneumonia. Our findings suggest that hospital experience may decrease mortality in this subset of patients with human immunodeficiency virus disease, although it is unknown whether this is due to differences in quality of care.

Acquired Immunodeficiency Syndrome↗