Biomedical subjects

J Robert Beck

Publications and source records attributed to J Robert Beck.

10 recordsLinked to original sources

PubMed2006

Using decision analysis to determine the cost-effectiveness of intensity-modulated radiation therapy in the treatment of intermediate risk prostate cancer.

BACKGROUND: The specific aim of this study is to evaluate the cost-effectiveness of intensity-modulated radiation therapy (IMRT) compared with three-dimensional conformal radiation therapy (3D-CRT) in the treatment of a 70-year-old with intermediate-risk prostate cancer. METHODS: A Markov model was designed with the following states; posttreatment, hormone therapy, chemotherapy, and death. Transition probabilities from one state to another were calculated from rates derived from the literature for IMRT and 3D-CRT. Utility values for each health state were obtained from preliminary studies of preferences conducted at Fox Chase Cancer Center. The analysis took a payer's perspective. Expected mean costs, cost-effectiveness scatterplots, and cost acceptability curves were calculated with commercially available software. RESULTS: The expected mean cost of patients undergoing IMRT was $47,931 with a survival of 6.27 quality-adjusted life years (QALYs). The expected mean cost of patients having 3D-CRT was $21,865 with a survival of 5.62 QALYs. The incremental cost-effectiveness comparing IMRT with CRT was $40,101/QALYs. Cost-effectiveness acceptability curve analysis revealed a 55.1% probability of IMRT being cost-effective at a $50,000/QALY willingness to pay. CONCLUSION: Intensity-modulated radiation therapy was found to be cost-effective, however, at the upper limits of acceptability. The results, however, are dependent on the assumptions of improved biochemical disease-free survival with fewer patients undergoing subsequent salvage therapy and improved quality of life after the treatment. In the absence of prospective randomized trials, decision analysis can help inform physicians and health policy experts on the cost-effectiveness of emerging technologies.

Aged↗

PubMed2006

Preliminary testing of a just-in-time, user-defined values clarification exercise to aid lower literate women in making informed breast cancer treatment decisions.

OBJECTIVE: To report on the initial testing of a values clarification exercise utilizing a jewellery box within a computerized patient decision aid (CPtDA) designed to assist women in making a surgical breast cancer treatment decision. DESIGN: Pre-post design, with patients interviewed after diagnosis, and then after completing the CPtDA sometime later at their preoperative visit. SAMPLE: Fifty-one female patients, who are low literate and naïve computer users, newly diagnosed with early stage breast cancer from two urban public hospitals. INTERVENTION: A computerized decision aid that combines entertainment-education (edutainment) with enhanced (factual) content. An interactive jewellery box is featured to assist women in: (1) recording and reflecting over issues of concern with possible treatments, (2) deliberating over surgery decision, and (3) communicating with physician and significant others. OUTCOMES: Patients' use of the jewellery box to store issues during completion of the CPtDA, and perceived clarity of values in making a treatment decision, as measured by a low literacy version of the Decisional Conflict Scale (DCS). RESULTS: Over half of the participants utilized the jewellery box to store issues they found concerning about the treatments. On average, users flagged over 13 issues of concern with the treatments. Scores on the DCS Uncertainty and Feeling Unclear about Values subscales were lower after the intervention compared to before the decision was made. CONCLUSIONS: A values clarification exercise using an interactive jewellery box may be a promising method for promoting informed treatment decision making by low literacy breast cancer patients.

Adult↗

PubMed2005

Economic analysis of a phase III clinical trial evaluating the addition of total androgen suppression to radiation versus radiation alone for locally advanced prostate cancer (Radiation Therapy Oncology Group protocol 86-10).

PURPOSE: To evaluate the cost-effectiveness of adding hormone therapy to radiation for patients with locally advanced prostate cancer, using a Monte Carlo simulation of a Markov Model. METHODS AND MATERIALS: Radiation Therapy Oncology Group (RTOG) protocol 86-10 randomized patients to receive radiation therapy (RT) alone or RT plus total androgen suppression (RTHormones) 2 months before and during RT for the treatment of locally advanced prostate cancer. A Markov model was designed with Data Pro (TreeAge Software, Williamstown, MA). The analysis took a payer's perspective. Transition probabilities from one state of health (i.e., with no disease progression or with hormone-responsive metastatic disease) to another were calculated from published rates pertaining to RTOG 86-10. Patients remained in one state of health for 1 year. Utility values for each health state and treatment were obtained from the literature. Distributions were sampled at random from the treatment utilities according to a second-order Monte Carlo simulation technique. RESULTS: The mean expected cost for the RT-only treatments was 29,240 dollars (range, 29,138-29,403 dollars). The mean effectiveness for the RT-only treatment was 5.48 quality-adjusted life years (QALYs) (range, 5.47-5.50). The mean expected cost for RTHormones was 31,286 dollars (range, 31,058-31,555 dollars). The mean effectiveness was 6.43 QALYs (range, 6.42-6.44). Incremental cost-effectiveness analysis showed RTHormones to be within the range of cost-effectiveness at 2,153 dollars/QALY. Cost-effectiveness acceptability curve analysis resulted in a >80% probability that RTHormones is cost-effective. CONCLUSIONS: Our analysis shows that adding hormonal treatment to RT improves health outcomes at a cost that is within the acceptable cost-effectiveness range.

Androgen Antagonists↗

PubMed2004

Cost-effectiveness analysis of telemedicine to evaluate diabetic retinopathy in a prison population.

OBJECTIVE: A cost-effectiveness analysis was conducted to investigate the clinical and economic impact of teleophthalmology in evaluating diabetic retinopathy in prison inmates with type 2 diabetes. RESEARCH DESIGN AND METHODS: Based on a hypothetical teleophthalmology system to evaluate diabetic retinopathy patients with type 2 diabetes in a prison care setting, a Markov decision model was developed with probability and cost data derived primarily from published epidemiological and outcome studies. A 40-year-old African-American man with type 2 diabetes was used as a reference case subject. The number of quality-adjusted life-years (QALYs) gained was used as the clinical outcome, and the cost in U.S. dollars from the year 2003 was used as the economic outcome. Teleophthalmology and nonteleophthalmology strategies were compared using an expected QALYs calculation and two types of sensitivity analyses: probabilistic and traditional n-way sensitivity analyses. RESULTS: The teleophthalmology strategy dominates in the cost-effectiveness analysis for the reference case subject: 16,514/18.73 dollars QALYs for teleophthalmology and 17,590/18.58 dollars QALYs for nonteleophthalmology. Ninety percent of the Monte Carlo simulations showed cost effectiveness (annual cost/QALYs < or = 50,000 dollars) in the teleophthalmology strategy based on an assumed inmate population. Teleophthalmology is the better strategy if the number of diabetic inmates in the prison community is >500. CONCLUSIONS: Our cost-effectiveness analysis demonstrates that teleophthalmology holds great promise to reduce the cost of inmate care and reduce blindness caused by diabetic retinopathy in type 2 diabetic patients.

Blindness↗

PubMed2002

Determinants of mortality in patients with severe blunt head injury.

CONTEXT: Head injury is the leading cause of traumatic death in the United States. HYPOTHESIS: A set of clinical parameters available soon after injury can be used to accurately predict outcome in patients with severe blunt head trauma. DESIGN: Validation cohort study. SETTING: Urban level I trauma center. PATIENTS AND METHODS: Data from patients with severe blunt head injury, as defined by inability to follow commands, were prospectively entered into a neurosurgical database and analyzed. The impact on survival of 23 potentially predictive parameters was studied using univariate analysis. Logistic regression models were used to control for confounding factors and to assess interactions between variables, whose significance was determined by univariate analysis. Goodness of fit was calculated with the Hosmer-Lemeshow c statistic. The predictability of the logistic model was evaluated by measuring the area under the receiver operating characteristic curve (AUC). RESULTS: Logistic regression analysis revealed that 5 risk factors were independently associated with death. These variables included systemic hypotension in the emergency department, midline shift on computed tomographic scan, intracranial hypertension, and absence of pupillary light reflex. A low Glasgow Coma Scale score and advanced age were found to be highly correlated risk factors that, when combined, were independently associated with mortality. The model showed acceptable goodness of fit, and the AUC was 80.5%. CONCLUSIONS: Systemic hypotension and intracranial hypertension are the only independent risk factors for mortality that can be readily treated during the initial management of patients with severe head injuries. When used together, Glasgow Coma Scale score and age are significant predictors of mortality.

Adolescent↗

PubMed2002

Yield and cost of individual common diagnostic tests in new primary care outpatients in Japan.

BACKGROUND: Appropriate diagnostic testing involves considerations of cost-effectiveness. We examined the cost-effectiveness of individual tests in a panel of tests defined by the Japan Society of Clinical Pathology. METHODS: We studied 540 new, symptomatic primary care outpatients with a set of 30 common diagnostic tests [the Essential Laboratory Tests (2); ELT(2) panel] for clinical evaluation and identification of occult disease. A useful result (UR) of testing was defined as a finding that contributed to a change in a physician's diagnosis or decision-making relating to a "tentative initial diagnosis" obtained from history and physical examination alone. RESULTS: The ELT(2) panel testing yielded 398 URs and uncovered 261 occult diseases among 540 patients. In total, 1592 tests contributed to either UR-generation or discovery of occult disease. The cost per effective test (cost required per test that contributed to either definition of effectiveness) ranged from 108 yen (approximately 0.92 US dollars) for total cholesterol to 6200 yen (approximately 52.50 dollars) for chest x-ray. Contribution rates and the cost per effective test varied among disease categories. We restructured panel components considering the effectiveness of each test. Subsets of the ELT(2) would have improved cost-effectiveness and achieved cost savings in five of eight disease categories. CONCLUSIONS: Assembly of tests based on cost-effectiveness can improve clinical efficiency and decrease total cost of panel testing for selected patient groups.

Adolescent↗

PubMed2001

Feature mining and predictive model construction from severe trauma patient's data.

In management of severe trauma patients, trauma surgeons need to decide which patients are eligible for damage control. Such decision may be supported by utilizing models that predict the patient's outcome. The study described in this paper investigates the possibility to construct patient outcome prediction models from retrospective patient's data at the end of initial damage control surgery by using feature mining and machine learning techniques. As the data used comprises rather excessive number of features, special attention was paid to the problem of selecting only the most relevant features. We show that a small subset of features may carry enough information to construct reasonably accurate prognostic models. Furthermore, the techniques used in our study identified two factors, namely the pH value when admitted to ICU and the worst partial active thromboplastin time, to be of highest importance for prediction. This finding is pathophysiologically reasonable and represents two of three major problems with severe trauma patients, metabolic acidosis, hypothermia, and coagulopathy.

Algorithms↗

PubMedDate not supplied

Survival and cost analysis of fatalities of the Kobe earthquake in Japan.

OBJECTIVES: The authors investigated the dying patterns, and cause and preventability of deaths in a major earthquake disaster, and estimated the cost needed to enhance emergency medical services (EMS) response to prevent "unnecessary" deaths. METHODS: The authors reviewed autopsy data in the Hanshin-Awaji (Kobe) earthquake of 1995. A survival analysis was performed to determine the time course and pattern of dying of these deaths. A cost analysis to estimate acceptable cost for EMS to reduce fatalities was also performed. Potentially salvageable life-years based on expected life-years among fatalities were calculated and used to simulate an acceptable cost for an enhanced EMS disaster response. RESULTS: The authors analyzed 5,411 fatalities. More than 80% of these patients died within three hours. There were statistically significant differences in survival/dying patterns among causes of death. Thirteen percent of victims experienced a protracted death, which could have been prevented with earlier medical or surgical intervention. The monetary cost of these lost lives was estimated at approximately 600 million US dollars. CONCLUSIONS: Survival analysis revealed a significant population of potentially salvageable patients if more timely and appropriate medical intervention had been available immediately after the earthquake. Based on our cost analysis, and assuming a 1% annual probability of an earthquake and a 30% enhanced lifesaving capability of the EMS effort, approximately $ million dollars annually could be a reasonable expenditure to achieve the goal of reducing preventable deaths in disasters.

Cohort Studies↗

PubMedDate not supplied

GenePath: a system for inference of genetic networks and proposal of genetic experiments.

A genetic network is a formalism that is often used in biology to represent causalities and reason about biological phenomena related to genetic regulation. We present GenePath, a computer-based system that supports the inference of genetic networks from a set of genetic experiments. Implemented in Prolog, GenePath uses abductive inference to elucidate network constraints based on background knowledge and experimental results. Additionally, it can propose genetic experiments that may further refine the discovered network and establish relations between genes that could not be related based on the original experimental data. We illustrate GenePath's approach and utility on analysis of data on aggregation and sporulation of the soil amoeba Dictyostelium discoideum.

Animals↗

PubMedDate not supplied

Collecting direct non-health care and time cost data: application to screening and diagnosis of cervical cancer.

BACKGROUND: Data on direct non-health care and time costs are rarely collected, though the incorporation of such data is essential for performing cost-effectiveness analyses according to established guidelines. OBJECTIVES: To explore the challenges involved in collecting and analyzing these data from patients enrolled in a clinical trial. METHODS: Through the use of a pilot study, the authors designed a questionnaire to collect these costs. They used this questionnaire in a clinical trial conducted at a comprehensive cancer center and a public community hospital. Patients in the trial were undergoing screening or diagnostic procedures through a clinical protocol designed to measure the effectiveness of fluorescence and reflectance spectroscopy for detecting cervical precancers. Direct non-health care costs were adjusted to 2003 constant dollars. RESULTS: The authors successfully collected direct non-health care and time cost data, thus demonstrating the feasibility of acquiring such data. Compared to patients receiving diagnostic services for cervical cancer, those receiving screening services for the same condition in both settings incurred lower direct non-health care costs and time costs, as defined in the questionnaire. Compared to patients receiving either service at the comprehensive cancer center, those seeking either service at the public community hospital incurred lower direct non-health care costs and time costs. When outliers were removed, total direct non-health care costs and time costs substantially decreased for diagnostic patients in the comprehensive cancer center; total direct non-health care costs and time costs for other subgroups remained essentially unchanged. CONCLUSIONS: Direct non-health care and time cost data can be collected within a large-scale clinical trial. The setting (community v. specialty hospital) and population (patients receiving screening v. diagnostic examination) makes a difference regarding the cost totals. The order of magnitude of the final result depends on the context in which the non-health care and time cost data will be used.

Adult↗