21 research outputs found
Polyimide based amorphous silicon solar modules
Requirements for space power are increasingly emphasizing lower costs and higher specific powers. This results from new fiscal constraints, higher power requirements for larger applications, and the evolution toward longer distance missions such as a Lunar or Mars base. The polyimide based a-Si modules described are being developed to meet these needs. The modules consist of tandem a-Si solar cell material deposited directly on a roll of polyimide. A laser scribing/printing process subdivides the deposition into discrete cell strips which are series connected to produce the required voltage without cutting the polymer backing. The result is a large, monolithic, blanket type module approximately 30 cm wide and variable in length depending on demand. Current production modules have a specific power slightly over 500 W/Kg with room for significant improvement. Costs for the full blanket modules range from 150/Watt depending on quantity and engineering requirements. Work to date focused on the modules themselves and adjusting them for the AMO spectrum. Work is needed yet to insure that the modules are suitable for the space environment
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The impact of self-monitoring in chronic illness on healthcare utilisation: a systematic review of reviews
Background: Self-management interventions have been found to reduce healthcare utilisation in people with long-term conditions, but further work is needed to identify which components of these interventions are most effective. Self-monitoring is one such component and is associated with significant clinical benefits. The aim of this systematic review of reviews is to assess the impact of self-monitoring interventions on healthcare utilisation across a range of chronic illnesses.
Methods: An overview of published systematic reviews and meta-analyses. Multiple databases were searched (MEDLINE, CINAHL, PsycINFO, EMBASE, AMED, EBM and HMIC) along with the reference lists of included reviews. A narrative synthesis was performed, accompanied by calculation of the Corrected Cover Area to understand the impact of overlapping primary research papers.
Results: A total of 17 systematic reviews and meta-analyses across three chronic conditions, heart failure, hypertension and chronic obstructive pulmonary disease, were included. Self-monitoring was associated with significant reductions in hospitalisation and re-admissions to hospital.
Conclusions: Self-monitoring has the potential to reduce the pressure placed on secondary care services, but this may lead to increase in services elsewhere in the system. Further work is needed to determine how these findings affect healthcare costs
Exacerbations among chronic bronchitis patients treated with maintenance medications from a US managed care population: an administrative claims data analysis
Azza AbuDagga,1 Shawn X Sun,2 Hiangkiat Tan,1 Caitlyn T Solem3 1HealthCore Inc, Wilmington, DE, 2Forest Research Institute, Jersey City, NJ, 3Pharmerit North America, Bethesda, MD, USA Purpose: Chronic obstructive pulmonary disease (COPD) exacerbations are the leading cause of hospital admission and death among chronic bronchitis (CB) patients. This study estimated annual COPD exacerbation rates, related costs, and their predictors among patients treated for CB. Methods: This was a retrospective study using claims data from the HealthCore Integrated Research Database (HIRDSM). The study sample included CB patients aged ≥ 40 years with at least one inpatient hospitalization or emergency department visit or at least two office visits with CB diagnosis from January 1, 2004 to May 31, 2011, at least two pharmacy fills for COPD medications during the follow-up year, and ≥2 years of continuous enrollment. COPD exacerbations were categorized as severe or moderate. Annual rates, costs, and predictors of exacerbations during follow-up were assessed. Results: A total of 17,382 individuals treated for CB met the selection criteria (50.6% female; mean ± standard deviation age 66.7 ± 11.4 years). During the follow-up year, the mean ± standard deviation number of COPD maintenance medication fills was 7.6 ± 6.3; 42.6% had at least one exacerbation and 69.5% of patients with two or more exacerbations during the 1 year prior to the index date (baseline period) had any exacerbation during the follow-up year. The mean ± standard deviation cost per any exacerbation was 269 ± 748 for moderate and 18,120 ± 31,592 for severe exacerbation. The number of baseline exacerbations was a significant predictor of the number of exacerbations and exacerbation costs during follow-up. Conclusion: Exacerbation rates remained high among CB patients despite treatment with COPD maintenance medications. New treatment strategies, designed to reduce COPD exacerbations and associated costs, should focus on patients with high prior-year exacerbations. Keywords: chronic bronchitis, chronic obstructive pulmonary disease, exacerbations, maintenance medications, managed car
PRS19 Exacerbations and Costs in Chronic Bronchitis Patients Treated with Copd Medications from a Managed Care Population in the United States
Placebo-only-controlled versus active-controlled trials of new drugs for nine common life-threatening diseases
Sarah Sorscher, Azza AbuDagga, Sammy Almashat, Michael A Carome, Sidney M Wolfe Health Research Group, Public Citizen, Washington, DC, USA Purpose: The Food and Drug Administration (FDA) permits investigators to withhold active interventions from human subjects randomly assigned to control groups in clinical trials. The scope of this practice in trials for life-threatening diseases is unknown. We assessed the frequency and characteristics of trials providing control group subjects with active interventions versus those providing only placebos to control group subjects in trials supporting FDA approvals of new drugs for nine life-threatening diseases. Materials and methods: We reviewed the FDA’s database of approved drug products and identified all new approvals from 2006 to 2011 for drugs or biological products indicated for asthma, bipolar disorder, chronic obstructive pulmonary disease (COPD), diabetes mellitus, hypertension, osteoporosis, Parkinson’s disease, partial seizures, and schizophrenia. Then, we identified all trials described in FDA medical review documents for these approvals and abstracted information on trial characteristics and the interventions provided to control group subjects. Results: Of 508 included trials, 201 (39.6%) were placebo-only-controlled, meaning subjects in at least one control group did not receive an active intervention, and 307 (60.4%) were active-controlled, meaning subjects in all control groups received an active intervention. The total recorded enrollments in control groups provided with placebos only and in control groups provided with active interventions were 19,361 and 93,093 subjects, respectively. The proportion of placebo-only-controlled trials varied across diseases (P<0.001), ranging from 75.5% for COPD to 0% for partial seizures and osteoporosis. Placebo-only controls were used in 76.9% of trials for severe COPD, 56.4% of trials for severe hypertension, 43.8% of trials for moderate or severe persistent asthma, and 6.7% of trials for severely uncontrolled diabetes. Logistic regression analysis showed that longer trials were associated with lower odds of being placebo-only-controlled compared with shorter trials.Conclusion: Providing only placebos to control groups in trials for life-threatening diseases is a common practice, potentially entailing varying degrees of risk to subjects. Further research is warranted to assess the impact of this practice, particularly in trials of long duration and those involving subjects with severe disease. Keywords: drug approval, bioethics, medical ethics, Food and Drug Administration, research ethic