A systematic review of health economic models of opioid agonist therapies in maintenance treatment of non-prescription opioid dependence

Background: Opioid dependence is a chronic condition with substantial health, economic and social costs. The study objective was to conduct a systematic review of published health-economic models of opioid agonist therapy for non-prescription opioid dependence, to review the different modelling approaches identified, and to inform future modelling studies. Methods: Literature searches were conducted in March 2015 in eight electronic databases, supplemented by hand-searching reference lists and searches on six National Health Technology Assessment Agency websites. Studies were included if they: investigated populations that were dependent on non-prescription opioids and were receiving opioid agonist or maintenance therapy; compared any pharmacological maintenance intervention with any other maintenance regimen (including placebo or no treatment); and were health-economic models of any type. Results: A total of 18 unique models were included. These used a range of modelling approaches, including Markov models (n = 4), decision tree with Monte Carlo simulations (n = 3), decision analysis (n = 3), dynamic transmission models (n = 3), decision tree (n = 1), cohort simulation (n = 1), Bayesian (n = 1), and Monte Carlo simulations (n = 2). Time horizons ranged from 6 months to lifetime. The most common evaluation was cost-utility analysis reporting cost per quality-adjusted life-year (n = 11), followed by cost-effectiveness analysis (n = 4), budget-impact analysis/cost comparison (n = 2) and cost-benefit analysis (n = 1). Most studies took the healthcare provider’s perspective. Only a few models included some wider societal costs, such as productivity loss or costs of drug-related crime, disorder and antisocial behaviour. Costs to individuals and impacts on family and social networks were not included in any model. Conclusion: A relatively small number of studies of varying quality were found. Strengths and weaknesses relating to model structure, inputs and approach were identified across all the studies. There was no indication of a single standard emerging as a preferred approach. Most studies omitted societal costs, an important issue since the implications of drug abuse extend widely beyond healthcare services. Nevertheless, elements from previous models could together form a framework for future economic evaluations in opioid agonist therapy including all relevant costs and outcomes. This could more adequately support decision-making and policy development for treatment of non-prescription opioid dependence

General linear stability properties of monoclinal shallow waves

We analyze the linear stability of monoclinal traveling waves on a constant incline, which connect uniform flowing regions of differing depths. The classical shallow-water equations are employed, subject to a general resistive drag term. This approach incorporates many flow rheologies into a single setting and enables us to investigate the features that set different systems apart. We derive simple formulae for the onset of linear instability, the corresponding linear growth rates and related properties including the existence of monoclinal waves, development of shocks and whether instability is initially triggered up- or downstream of the wave front. Also included within our framework is the presence of shear in the flow velocity profile, which is often neglected in depth-averaged studies. We find that it can significantly modify the threshold for instability. Constant corrections to the governing equations to account for sheared profiles via a 'momentum shape factor' act to stabilize traveling waves. More general correction terms are found to have a nontrivial and potentially important quantitative effect on the properties explored. Finally, we have investigated the spatial properties of the dominant (fastest growing) linear modes. We derive equations for their amplitude and frequency and find that both features can become severely amplified near the front of the traveling wave. For flood waves that propagate into a dry downstream region, this amplification is unbounded in the limit of high disturbance frequency. We show that the rate of divergence is a function of the spatial dependence of the wave depth profile at the front, which may be determined straightforwardly from the drag law.Comment: 27 pages, 9 figure

Renewable power options enabled by Local Electricity Trading.

The paper is prepared as part of an Australian Renewable Energy Agency (ARENA) funded research project led by the Institute for Sustainable Futures (ISF) at the University of Technology Sydney (UTS), Facilitating Local Network Charges and Virtual Net Metering and a project funded by the Victorian Government Department of Environment, Land, Water and Planning (DELWP), Virtual Renewable Power Stations. A key task in the ISF project is to run five virtual trials of Local Electricity Trading (LET)1 and local network charges, one of which will take place in the Moira Shire and Swan Hill Rural City Council areas in regional Victoria. The Moira and Swan Hill trial will examine either the business model for a one-to-many (Community Power Station) or for a many-to-one (also called a Virtual Power Station, or VPS). Both of these models are likely to be enabled if Local Electricity Trading becomes commonly available. The primary interest of the Councils is to improve the resilience of the local economy by retaining energy spending within the area, to increase the capacity of local renewable energy generation and to enable local residents and businesses to participate in the renewable energy generation. The purpose of this paper is to assist the Councils to choose which model to take forward into a trial

Local Network Charges and Local Electricity Trading: Market Scan

This report provides an overview of current literature and information relating to local network charges, local electricity trading (also called virtual net metering or VNM), and virtual power stations. The focus is information particularly relevant to Australia, as well as global precedents in each area