108 research outputs found
How do we determine whether community health workers are cost-effective? Some core methodological issues.
Since the Alma-Ata Conference in 1978 reiterated the goal of "Health for All by the Year 2000", health service delivery programs promoting the primary health care approach using community health workers (CHWs) have been established in many developing countries. These programs are expected to improve the cost-effectiveness of health care systems by reaching large numbers of previously underserved people with high-impact basic services at low cost. However, there is a dearth of data on the cost-effectiveness of CHW programs to confirm these views. This may be because conventional approaches to economic evaluation, particularly cost-effectiveness, tend not to capture the institutional features of CHW programs. Therefore, this paper aims to examine the means by which economic methods can be extended to provide evidence regarding the cost-effectiveness of CHWs in developing countries
Effects of human cytomegalovirus infection on the coagulation system
Pathophysiological mechanisms of acute vascular thrombosis are not fully understood. It has been suggested that different infectious pathogens are responsible agents of thrombotic disorders. The infection hypothesis is supported by an increasing number of reports on the interaction between acute infection and coagulation. Cytomegalovirus (CMV) is supposed to play an important role in apparently unprovoked thrombosis. We reviewed all human in vitro and in vivo studies on the influence of human CMV infection on the coagulation system, as well as all case reports of acute thrombosis during acute human CMV infection. In the published literature there is mounting evidence that human CMV may play a role in thrombotic disorders. Definitive conclusions, however, cannot be drawn, although the in vitro studies are convincing and offer insight in the pathogenesi
An economic analysis of midwifery training programmes in South Kalimantan, Indonesia.
In order to improve the knowledge and skills of midwives at health facilities and those based in villages in South Kalimantan, Indonesia, three in-service training programmes were carried out during 1995-98. A scheme used for both facility and village midwives included training at training centres, peer review and continuing education. One restricted to village midwives involved an internship programme in district hospitals. The incremental cost-effectiveness of these programmes was assessed from the standpoint of the health care provider. It was estimated that the first scheme could be expanded to increase the number of competent midwives based in facilities and villages in South Kalimantan by 1% at incremental costs of US 1175.7 respectively, and that replication beyond South Kalimantan could increase the number of competent midwives based in facilities and villages by 1% at incremental costs of US 1786.4 per midwife respectively. It was also estimated that the number of competent village midwives could be increased by 1% at an incremental cost of US 146.2 per intern for expanding the scheme in South Kalimantan. It was not clear whether the training programmes were more or less cost-effective than other safe motherhood interventions because the nature of the outcome measures hindered comparison
The cost effectiveness of universal antenatal screening for HIV in New Zealand.
OBJECTIVE: To model the incremental costs and benefits of a universal antenatal HIV screening programme in New Zealand (NZ). DESIGN: Cost effectiveness analysis, including only health service costs, using secondary data sources and expert opinion. Uncertainty assessed in multi-way sensitivity analyses. SETTING: The NZ Health Care System. SUBJECTS: Antenatal population of NZ. INTERVENTION: Universal antenatal HIV screening programme. MAIN OUTCOME MEASURES: Incremental cost per true-positive HIV case detected in mothers; incremental cost per HIV case avoided in babies; and incremental cost per discounted life-year gained, for mothers and babies, due to screening. RESULTS: Using base case values the application of universal screening would cost an additional US 307 917) and would lead to the identification of an additional 6.25 true-positive women. After terminations have been excluded, the screening programme would detect five HIV exposed babies. There would be 1.15 avoided cases of HIV infection in babies and a net gain of 41.97 discounted life-years, for mothers and babies combined. The cost per incremental HIV-positive woman detected was US 49 301), HIV infected baby avoided US 267 944) and discounted life-year gained US 7336). CONCLUSION: The discounted cost per life gained in NZ compares favourably to estimates reported in studies of similar interventions in other developed countries and other health care interventions in NZ. The decision of whether to implement universal screening in NZ would be clarified if the prevalence of antenatal HIV infection was known and policy makers identified their willingness to pay for an additional life-year gained
Supervised Learning in Spiking Neural Networks
Spiking neural networks are notoriously hard to train because of their complex dynamics and sparse spiking signals. However, in part due to these properties, spiking neurons possess high computa- tional power and high theoretical energy efficiency. This thesis introduces an online, supervised, and gradient-based learning algorithm for spiking neural networks. It is shown how gradients of temporal signals that influence spiking neurons can be calculated online as an eligibility trace. The trace rep- resents the temporal gradient as a single scalar value and is recursively updated at each consecutive iteration. Moreover, the learning method uses approximate error signals to simplify their calculation and make the error calculation compatible with online learning. In several experiments, it is shown that the algorithm can solve spatial credit assignment problems with short-term temporal dependencies in deep spiking neural networks. Potential approaches for improving the algorithm’s performance on long-term temporal credit assignment problems are also discussed. Besides the research on spiking neural networks, this thesis includes an in-depth literature study on the topics of neuromorphic computing and deep learning, as well as extensive evaluations of several learning algorithms for spiking neural networksAerospace Engineerin
Reliability Updating of Sheet Pile Walls: An analysis on the parameter updating process
Throughout the years the requirements of sheet pile walls have changed. Therefore reassessment of these structure's reliability is of importance. In this thesis, Bayesian updating is used for the reliability updating task. Updating processes require measurements of the structure under known conditions. Although for practical and economical reasons failure measurements of structures are seldomely available. Therefore the research focusses on whether it is possible to update a sheet pile wall's reliability using service domain measurements instead. Parameter updating methods generally return the statistically most likely parameter values for producing the observations. Using a theoretical sheet pile wall case, it is tested if the Bayesian updating method is able to effectively return the true soil parameter values as the most likely parameter set. The results show that the Bayesian updating method is very capable of approaching the used observations with the updated model response. Also the updated values of the most influential parameters show evolution in the direction of their true values. But the method does have difficulties with returning the true soil parameter values, even when applied to a theoretical case and with the use of elaborate observation configurations. Recommendations are given on further research concerning the use of the Bayesian updating method, the different influences on its performance and method application limitations.Geotechnical Engineerin
- …
