Valuing natural assets

Key points New Zealand producers and consumers get much value from natural assets. Much of this value is intangible. This is a fundamental reason to make special effort to measure the value of natural assets, to make sure we make the right decisions about their use and conservation.But a key barrier to using economic valuation is the cost and uncertainty of values obtained from the variety of techniques being used. This is a real issue, to the extent that doubts are being expressed in resource management cases whether economics has much to add when considering environmental effects.To remove this barrier, valuations need to be cheaper and easier to compare. A standardised technique could provide relative values for different types of natural asset or service. This would make economic value estimates from across a range of natural asset settings more consistent.Developing a practical, reliable standardised technique would involve: building on studies done to date , showing how much economic activity depends on natural assets in a robust and comparable waycarrying out a meta - analysis, to obtain consistent and comparable value estimates for a range of ensure economic activities from economic impact studies done to datelearning how biophysical cause - and - effect relationships translate into economic value, to identify the sensitivity of econo mic activity to changes in natural assets , such as biodiversitycommissioning a stated preference study of the value of broad categories of natural assets, as a starting point for identifying value in specific situations. Decision - makers need to understand how and where economic valuation can support their decisions. Providing them with explanatory materials will help.It is important to make progress. There is currently a gap in the knowledge about the full contribution of natural assets to New Zealand’s economic well-being. This creates a risk that natural assets will be undervalued. Ecosystems and the valuable services they provide may be lost or damaged.Economic valuation of environmental assets can fill the knowledge gap. To date, non-market valuations in New Zealand do not appear to have been used much to make management choices in conservation, whether those relate to responding to pest incursions or to economic development.A less ad hoc approach to weighing up the value of natural assets can make treatment of natural assets more consistent in decisions, and increase the efficiency of use of natural resources. A better approach is needed so studies inform policy and decisions about New Zealand’s natural assets. Our proposed approach could improve understanding of the value of natural assets — giving them more consistent weight in decisions, and improving the way we manage them

Frequency, factors and costs associated with injection site infections: findings from a national multi-site survey of injecting drug users in England.

BACKGROUND: Injection site infections among injecting drug users (IDUs) have been associated with serious morbidity and health service costs in North America. This study explores the frequency, factors and costs associated with injection site infections among IDUs in England. METHODS: Unlinked-anonymous survey during 2003/05 recruiting IDUs from community settings at seven locations across England. Self-reported injecting practice, symptoms of injection site infections (abscess or open wound) and health service utilisation data were collected using a questionnaire, participants also provided dried blood spot samples (tested for markers blood borne virus infections). Cost estimates were obtained by combining questionnaire data with information from national databases and the scientific literature. RESULTS: 36% of the 1,058 participants reported an injection site infection in the last year. Those reporting an injection site infection were more likely to be female and aged over 24, and to have: injected into legs, groin, and hands in last year; injected on 14 or more days during the last four weeks; cleaned needles/syringes for reuse; injected crack-cocaine; antibodies to hepatitis C; and previously received prescribed substitute drug. Two-thirds of those with an injection site infection reported seeking medical advice; half attended an emergency department and three-quarters of these reported hospital admission. Simple conservative estimates of associated healthcare costs range from pound 15.5 million per year to as high as pound 30 million; though if less conservative unit costs assumptions are made the total may be much higher (pound 47 million). The vast majority of these costs are due to hospital admissions and the uncertainty is due to little data on length of hospital stays. CONCLUSION: Symptoms of injection site infections are common among IDUs in England. The potential costs to the health service are substantial, but these costs need more accurate determination. Better-targeted interventions to support safer injection need to be developed and evaluated. The validity of self-reported symptoms, and the relationship between symptoms, infection severity, and health seeking behaviour require further research

Beyond learning by doing: an exploration of critical incidents in outdoor leadership education

This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Adventure Education and Outdoor Learning on 3rd August 2015 (online), available online: DOI:10.1080/14729679.2015.1051564This paper argues that outdoor leader education and training is generally characterized by the development of procedural skills at the expense of equally crucial but usually ignored, ‘soft skills’ (for example, contextualized decision making and reflection). Consequently, this risks producing practitioners with a potentially unsophisticated and limited awareness of the holistic outdoor environments and situations and an over-reliance on ‘how to’ skills which may, in turn, impede the development of links between theory and practice. This paper analyses a research project that undertook the application of critical incident theory to a study of undergraduates in a United Kingdom outdoor leadership degree programme in an attempt to promote and examine the processes of developing ‘softer’ reflective skills in the students. In addition, the paper’s argument and data, while not directly dealing with wider audiences (clients and national qualification bodies), provide inferences and allusions to potential consequent enhanced development and benefits of heightened reflective understanding and practice to these groups. Methodologically, the study examines a range of critical incidents in a purposive homogenous sample of 20 students from a vocational undergraduate outdoor studies course. Students were asked to identify and reflect on critical incidents in practice settings of their own choice. These settings spanned a range of contexts from outdoor centre work in the United Kingdom to assistant leadership positions on educational expeditions in remote locations overseas. Qualitative data analysis was carried out through the use of Interpretative Phenomenological Analysis (IPA). The findings supported the conceptual premise and indicated that outdoor leadership programmes need to develop a broader and holistic skills base rather than persist with the extant predilection towards primarily physical and technical skills. Allusion is made to the suggestion that this could ultimately potentially enhance effectiveness with clients and employability prospects. In summary, a focus on critical incident method early in education and training processes has the potential to equip practitioners with the holistic and complex set of skills required in the contemporary outdoor workplace

Optimal control of hepatitis C antiviral treatment programme delivery for prevention amongst a population of injecting drug users.

In most developed countries, HCV is primarily transmitted by injecting drug users (IDUs). HCV antiviral treatment is effective, and deemed cost-effective for those with no re-infection risk. However, few active IDUs are currently treated. Previous modelling studies have shown antiviral treatment for active IDUs could reduce HCV prevalence, and there is emerging interest in developing targeted IDU treatment programmes. However, the optimal timing and scale-up of treatment is unknown, given the real-world constraints commonly existing for health programmes. We explore how the optimal programme is affected by a variety of policy objectives, budget constraints, and prevalence settings. We develop a model of HCV transmission and treatment amongst active IDUs, determine the optimal treatment programme strategy over 10 years for two baseline chronic HCV prevalence scenarios (30% and 45%), a range of maximum annual budgets (£50,000-300,000 per 1,000 IDUs), and a variety of objectives: minimising health service costs and health utility losses; minimising prevalence at 10 years; minimising health service costs and health utility losses with a final time prevalence target; minimising health service costs with a final time prevalence target but neglecting health utility losses. The largest programme allowed for a given budget is the programme which minimises both prevalence at 10 years, and HCV health utility loss and heath service costs, with higher budgets resulting in greater cost-effectiveness (measured by cost per QALY gained compared to no treatment). However, if the objective is to achieve a 20% relative prevalence reduction at 10 years, while minimising both health service costs and losses in health utility, the optimal treatment strategy is an immediate expansion of coverage over 5-8 years, and is less cost-effective. By contrast, if the objective is only to minimise costs to the health service while attaining the 20% prevalence reduction, the programme is deferred until the final years of the decade, and is the least cost-effective of the scenarios

Cost-effectiveness of HCV case-finding for people who inject drugs via dried blood spot testing in specialist addiction services and prisons

ObjectivesPeople who inject drugs (PWID) are at high risk for acquiring hepatitis C virus (HCV), but many are unaware of their infection. HCV dried blood spot (DBS) testing increases case-finding in addiction services and prisons. We determine the cost-effectiveness of increasing HCV case-finding among PWID by offering DBS testing in specialist addiction services or prisons as compared to using venepuncture.DesignCost-utility analysis using a dynamic HCV transmission model among PWID, including: disease progression, diagnosis, treatment, injecting status, incarceration and addition services contact.Setting uk interventionDBS testing in specialist addiction services or prisons. Intervention impact was determined by a meta-analysis of primary data.Primary and secondary outcome measuresCosts (in UK £, £1=US$1.60) and utilities (quality-adjusted life years, QALYs) were attached to each state and the incremental cost effectiveness ratio (ICER) determined. Multivariate uncertainty and one-way sensitivity analyses were performed.ResultsFor a £20 000 per QALY gained willingness-to-pay threshold, DBS testing in addiction services is cost-effective (ICER of £14 600 per QALY gained). Under the base-case assumption of no continuity of treatment/care when exiting/entering prison, DBS testing in prisons is not cost-effective (ICER of £59 400 per QALY gained). Results are robust to changes in HCV prevalence; increasing PWID treatment rates to those for ex-PWID considerably reduces ICER (£4500 and £30 000 per QALY gained for addiction services and prison, respectively). If continuity of care is >40%, the prison DBS ICER falls below £20 000 per QALY gained.ConclusionsDespite low PWID treatment rates, increasing case-finding can be cost-effective in specialist addiction services, and in prisons if continuity of treatment/care is ensured

The investigation of interferences in immunoassay

Immunoassay procedures have a wide application in clinical medicine and as such are used throughout clinical biochemistry laboratories both for urgent and routine testing. Clinicians and laboratory personnel are often presented with immunoassay results which are inconsistent with clinical findings. Without a high index of suspicion interferences will often not be suspected. Artifactual results can be due to a range of interferences in immunoassays which can include cross reacting substances, heterophile antibodies, autoantibodies and the high dose hook effect. Further, pre-analytical aspects and certain disease states can influence the potential for interference in immunoassays. Practical solutions for investigation of artifactual results in the setting of the routine clinical laboratory are provided

Is the HCV-HIV co-infection prevalence amongst injecting drug users a marker for the level of sexual and injection related HIV transmission?

BACKGROUND: Amongst injecting drug users (IDUs), HIV is transmitted sexually and parenterally, but HCV is transmitted primarily parenterally. We assess and model the antibody prevalence of HCV amongst HIV-infected IDUs (denoted as HCV-HIV co-infection prevalence) and consider whether it proxies the degree of sexual HIV transmission amongst IDUs. METHODS: HIV, HCV and HCV-HIV co-infection prevalence data amongst IDU was reviewed. An HIV/HCV transmission model was adapted. Multivariate model uncertainty analyses determined whether the model's ability to replicate observed data trends required the inclusion of sexual HIV transmission. The correlation between the model's HCV-HIV co-infection prevalence and estimated proportion of HIV infections due to injecting was evaluated. RESULTS: The median HCV-HIV co-infection prevalence (prevalence of HCV amongst HIV-infected IDUs) was 90% across 195 estimates from 43 countries. High HCV-HIV co-infection prevalences (>80%) occur in most (75%) settings, but can be lower in settings with low HIV prevalence (0.75). The model without sexual HIV transmission reproduced some data trends but could not reproduce any epidemics with high HIV/HCV prevalence ratios (>0.85) or low HCV-HIV co-infection prevalence (10%. The model with sexual HIV transmission reproduced data trends more closely. The proportion of HIV infections due to injecting correlated with HCV-HIV co-infection prevalence; suggesting that up to 80/60/90%. CONCLUSION: Substantial sexual HIV transmission may occur in many IDU populations; HCV-HIV co-infection prevalence could signify its importance