Methods for a composite ecological suitability measure to inform cumulative restoration assessments in Gulf of Mexico estuaries.

Ecosystem management requires a systematic, holistic approach that considers ecological and social outcomes. Effective restoration practices promote a balance of ecological and social goals by addressing ecological integrity, efficiently maximizing benefits while minimizing investment, and encompassing collaborative stakeholder engagement. Socio-ecological assessments can inform adaptive management and be utilized to prioritize restoration activities and monitor restoration effectiveness. In estuarine systems, socio-ecological assessments should evaluate the ability of habitats to support both ecologically and locally important species. The composite measure presented utilizes a combination of ecological and social measures to characterize ecological suitability for individual and multiple Gulf of Mexico estuarine species. The ecological suitability value (ES) for a given spatial unit is based on a suite of biophysical measures of the quality and extent of suitable habitat for each species, the species' trophic importance in a food web context, and the importance of each species in relation to stakeholder values and benefits. ES values for individual spatial units can be aggregated to estimate the distribution of ecological suitability at the estuarine scale. The ES values are calculated using examples for each step in the process. The information provided by ecological suitability characterizations can support restoration prioritization decisions for Gulf of Mexico estuaries and can provide a baseline measure to gauge restoration effectiveness over time to inform cumulative restoration assessments.

Predation Strategies of the Bacterium Bdellovibrio bacteriovorus Result in Overexploitation and Bottlenecks.

With increasing antimicrobial resistance, alternatives for treating infections or removing resistant bacteria are urgently needed, such as the bacterial predator Bdellovibrio bacteriovorus or bacteriophage. Therefore, we need to better understand microbial predator-prey dynamics. We developed mass-action mathematical models of predation for chemostats, which capture the low substrate concentration and slow growth typical for intended application areas of the predators such as wastewater treatment, aquaculture, or the gut. Our model predicted that predator survival required a minimal prey cell size, explaining why Bdellovibrio is much smaller than its prey. A predator considered to be "too good" (attack rate too high, mortality too low) overexploited its prey, leading to extinction (tragedy of the commons). Surprisingly, a predator taking longer to produce more offspring outcompeted a predator producing fewer offspring more rapidly (rate versus yield trade-off). Predation was only efficient in a narrow region around optimal parameters. Moreover, extreme oscillations under a wide range of conditions led to severe bottlenecks. These could be avoided when two prey species became available in alternating seasons. A bacteriophage outcompeted Bdellovibrio due to its higher burst size and faster life cycle. Together, results suggest that Bdellovibrio would struggle to survive on a single prey, explaining why it must be a generalist predator and suggesting it is better suited than phage to environments with multiple prey. IMPORTANCE The discovery of antibiotics led to a dramatic drop in deaths due to infectious disease. Increasing levels of antimicrobial resistance, however, threaten to reverse this progress. There is thus a need for alternatives, such as therapies based on phage and predatory bacteria that kill bacteria regardless of whether they are pathogens or resistant to antibiotics. To best exploit them, we need to better understand what determines their effectiveness. By using a mathematical model to study bacterial predation in realistic slow growth conditions, we found that the generalist predator Bdellovibrio is most effective within a narrow range of conditions for each prey. For example, a minimum prey cell size is required, and the predator should not be "too good," as this would result in overexploitation risking extinction. Together these findings give insights into the ecology of microbial predation and help explain why Bdellovibrio needs to be a generalist predator.

A conceptual approach to characterizing ecological suitability: Informing socio-ecological measures for restoration effectiveness.

A combination of ecological and socio-economic outcome indicators is essential for understanding and assessing the effectiveness of the remediation and restoration of degraded ecosystems and revitalizing communities that could benefit from these ecosystem management activities. In this paper, we propose and develop a conceptual approach to characterize ecological suitability that incorporates ecological attributes that support ecosystem structural diversity and functionality, stakeholder values and perceptions, and the benefits derived from ecosystem goods and services. A structured literature review was used to identify existing restoration frameworks and indicators to inform the conceptual foundation for characterizing ecological suitability. The structure of the conceptual approach primarily builds from ecological and social attributes in the International Principles and Standards for the Practice of Ecological Restoration (Gann et al., 2019). We provide a conceptual example of the ecological suitability approach in estuaries. This example is based on habitat suitability and food web characterizations in combination with the provisioning of ecosystem services and desired social benefits to prioritize and evaluate restoration effectiveness. This foundational work sets the stage for developing a composite measure of ecological suitability. The holistic conceptual approach presented complements existing information regarding restoration effectiveness evaluations. Characterizing ecological suitability is a novel way to incorporate ecological and social information and communicate potential restoration outcomes to ecosystem managers and stakeholders.

Dual Predation by Bacteriophage and Bdellovibrio bacteriovorus Can Eradicate Escherichia coli Prey in Situations where Single Predation Cannot.

Bacteria are preyed upon by diverse microbial predators, including bacteriophage and predatory bacteria, such as Bdellovibrio bacteriovorus While bacteriophage are used as antimicrobial therapies in Eastern Europe and are being applied for compassionate use in the United States, predatory bacteria are only just beginning to reveal their potential therapeutic uses. However, predation by either predator type can falter due to different adaptations arising in the prey bacteria. When testing poultry farm wastewater for novel Bdellovibrio isolates on Escherichia coli prey lawns, individual composite plaques were isolated containing both an RTP (rosette-tailed-phage)-like-phage and a B. bacteriovorus strain and showing central prey lysis and halos of extra lysis. Combining the purified phage with a lab strain of B. bacteriovorus HD100 recapitulated haloed plaques and increased killing of the E. coli prey in liquid culture, showing an effective side-by-side action of these predators compared to their actions alone. Using approximate Bayesian computation to select the best fitting from a variety of different mathematical models demonstrated that the experimental data could be explained only by assuming the existence of three prey phenotypes: (i) sensitive to both predators, (ii) genetically resistant to phage only, and (iii) plastic resistant to B. bacteriovorus only. Although each predator reduces prey availability for the other, high phage numbers did not abolish B. bacteriovorus predation, so both predators are competent to coexist and are causing different selective pressures on the bacterial surface while, in tandem, controlling prey bacterial numbers efficiently. This suggests that combinatorial predator therapy could overcome problems of phage resistance.IMPORTANCE With increasing levels of antibiotic resistance, the development of alternative antibacterial therapies is urgently needed. Two potential alternatives are bacteriophage and predatory bacteria. Bacteriophage therapy has been used, but prey/host specificity and the rapid acquisition of bacterial resistance to bacteriophage are practical considerations. Predatory bacteria are of interest due to their broad Gram-negative bacterial prey range and the lack of simple resistance mechanisms. Here, a bacteriophage and a strain of Bdellovibrio bacteriovorus, preyed side by side on a population of E. coli, causing a significantly greater decrease in prey numbers than either alone. Such combinatorial predator therapy may have greater potential than individual predators since prey surface changes selected for by each predator do not protect prey against the other predator.

Extended C-band tunable multi-channel InP-based coherent receiver PICs.

Fully integrated monolithic, multi-channel InP-based coherent receiver PICs and transceiver modules with extended C-band tunability are described. These PICs operate at 33 and 44 Gbaud per channel under dual polarization (DP) 16-QAM modulation. Fourteen-channel monolithic InP receiver PICs show integration and data rate scaling capability to operate at 44 Gbaud under DP 16-QAM modulation for combined 4.9 Tb/s total capacity. Six channel simultaneous operation of a commercial transceiver module at 33 Gbaud is demonstrated for a variety of modulation formats including DP 16-QAM for >1.2Tbit/s aggregate data capacity.

The prevalence and fate of the defunctioning stoma in patients with anal cancer: a regional experience following the ACT II trial.

AIM: UK guidance advises the creation of a defunctioning stoma for anal tumours infiltrating the vagina, impending obstruction or significant faecal incontinence. Other patients may be offered a defunctioning stoma at the discretion of the clinician. The purpose of this study was to establish the prevalence and fate of defunctioning stomas in a regional anal cancer service, with reference to the results from the recent ACT II trial. METHOD: Oncological treatment was standardized as described in the ACT II trial. All patients from 2010 to 2013 inclusive were included. Collected data were correlated with both the IMRT guidelines and the outcomes of the ACT II trial. Kaplan-Meier survival analysis was applied to stoma-free survival to the end of the study period. RESULTS: Seventy-six patients were identified during the study period, of whom 51% had a defunctioning stoma. Twenty were performed for anterior tumours without infiltration into the vagina (Group A), whilst 19 had a stoma for indications as set out by the guidelines (Group B). Stoma reversal was performed in 41% of patients, 13/20 in Group A and 3/19 in Group B. The median time to reversal was 11 months. Eleven deaths were recorded and six patients still had their stomas at time of death. Stoma-free survival was 74%. No new ano-vaginal fistulation occurred as a consequence of treatment. CONCLUSION: The tumour features that are indications for defunctioning as advised by the UK IMRT guidelines are associated with a poorer overall outcome, and these stomas are less likely to be reversed. The majority of stomas, however, were formed for anterior tumours without infiltration into the vagina and were more likely to be successfully reversed.

Reducing false positive diagnoses in mild cognitive impairment: the importance of comprehensive neuropsychological assessment.

BACKGROUND AND PURPOSE: Longitudinal studies of mild cognitive impairment (MCI) report that a sizeable proportion of MCI cases revert to normal levels of functioning over time. The rate of recovery from MCI indicates that existing MCI diagnostic criteria result in an unacceptably high rate of false positive diagnoses and lack adequate sensitivity and specificity. METHODS: The aim of the present study was to identify a set of neuropsychological measures able to differentiate between true positive cases of MCI from those who were unimpaired at 11 months' follow-up. RESULTS: A discriminant function analysis identified that a combination of measures of complex sustained attention, semantic memory, working memory, episodic memory and selective attention correctly classified outcome in more than 80% of cases. The rate of false positive diagnoses (5.93%) was considerably lower than is evident in previously published MCI studies. CONCLUSIONS: The results of the present study indicate that the rate of false positive MCI diagnoses can be significantly reduced through the use of sensitive and specific neuropsychological measures of memory and non-memory functions.

The role of social and intergenerational equity in making changes in human well-being sustainable.

A sustainable world is one in which human needs are met equitably and without sacrificing the ability of future generations to meet their needs. Human well-being is described by four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being. These elements can interact in a myriad of ways to influence overall well-being. What makes changes in human well-being sustainable for a population or a nation? Two major interactional concepts can push changes in human well-being toward a sustainable state in space and time-social equity and intergenerational equity. The concept of social equity distributes well-being over space, ensuring the fair treatment of all members of society promoting spatial sustainability of a well-being decision. The concept of intergenerational equity distributes well-being through time, ensuring the well-being of present and future generations of a population or nation, promoting temporal sustainability of a well-being decision. The roles of social and intergenerational equity in terms of their influence on human well-being are examined with a focus on more sustainable decision-making.

Development of Community-Level Capacity of Resilience to Natural Hazards for Environmental- and Social-Justice-Challenged Communities: 1. Approach, Concepts, and Assessment of Existing Information.

Impoverished and under-served communities are often exposed to the worst environmental and climate hazards. Identifying these communities and building their resilience capacity to withstand such hazards is a vital justice aspect of environmental management. Building community resilience requires five activities: (1) examination of existing information, (2) community engagement and assessment of local knowledge, (3) development of reasonable strategies to build resilience, (4) implementation and these strategies, and (5) monitoring and transability of the process. This manuscript examines the first component of this process. The attributes of multiple parishes in Louisiana are examined using available data and existing models of human well-being, community resilience, and environmental/climate/socioeconomic justice. These existing models and tools were used to determine parish-level resilience to natural hazards including flooding, hurricanes, and other potential natural climatic hazards in central Louisiana (U.S.). Through consultation with state officials and local community groups, candidate environmental justice (EJ) and social justice (SJ) communities were selected to develop resilience capacity enhancement plans to address potential adverse parish and community outcomes of natural hazard events. Of the available parishes, St. Helena Parish was selected as an entity that would significantly benefit from resilience capacity building. The remaining two activities, community engagement and strategy development, will be examined in sister manuscripts. Continuing studies, to be described elsewhere, will describe community engagement and the determination of strategies, implementation plans, and the monitoring of the success of these strategic implementations.

Impact of war on veteran life span: natural experiment involving combat versus non-combat exposed military personnel.

INTRODUCTION: There is still uncertainty around the impact of combat exposure on the life span of war veterans. Therefore we made use of a natural experiment to study the impact on veteran life span of combat versus non-combat exposure in World War II (WW2). METHODS: The combat-exposed military personnel were derived from a random (10%) sample of the military roll of the 28th (Maori) Battalion from New Zealand. One non-combat cohort was the 15th Reinforcements of this same Battalion, since the war ended before they reached the front line. The other non-combat cohort were Maori personnel who were only involved in Jayforce, which occupied Japan at the end of the WW2. Data on life span were mainly derived from an official repository of birth and death records, but supplemented with other sources, including military files. RESULTS: When comparing life spans of service veterans, there was no statistically significant reduction for the average life span of the 234 combat-exposed veterans in our sample from the 28th (Maori) Battalion (66.7 years), relative to the Maori veterans from two non-combat cohorts: the 132 personnel in the 15th Reinforcements (67.2 years) and the 147 personnel in Jayforce (66.9 years). CONCLUSIONS: Despite a very high level of wounding in the combat-exposed group (48%), there were no statistically significant reductions in life span between this group and comparable non-combat exposed veterans. This finding contrasts to life span reductions found in a similar study of New Zealand veterans of WW1.

Comparison of ionised calcium measured using a portable analyser to a reference method in healthy dogs.

OBJECTIVES: To compare the ionised calcium measured on a portable analyser (iSTAT, Abbott) to a reference method. MATERIALS AND METHODS: Blood samples from 39 apparently healthy dogs were analysed in duplicate using a portable analyser and a reference method (Radiometer ABL800 FLEX). Bland-Altman plots and Passing-Bablok regression were used to assess constant and proportional bias between the two instruments. A within-assay percentage coefficient of variation and total error (TE) was calculated for both analysers. The reference interval was calculated for the portable analyser using the robust method with confidence interval bootstrapping. RESULTS: The Bland-Altman plot showed a -0.036 mmol/L difference between the two instruments (95% confidence limit -0.08 to 0.01 mmol/L; limits of agreement -0.07 to 0.006 mmol/L). Neither the Bland-Altman plot nor the Passing-Bablock regression (slope -0.03; 95% confidence interval -0.08 to 0.19 and intercept 1; 95% confidence interval 0.83 to 1.2) showed significant proportional bias. The coefficient of variation for the portable analyser was 1.08%, compared to 0.78% for the reference method with a total error of 3.5% for the portable analyser. The estimated population-based reference interval for ionised calcium using the portable analyser is 1.23 to 1.42 mmol/L. CLINICAL SIGNIFICANCE: For the healthy dogs in this study, compared to the reference method, the portable analyser showed no significant bias for measurement of ionised calcium. Further studies including hyper and hypocalcaemic dogs are required to determine clinical impact of the use of this analyser.

A review of the elements of human well-being with an emphasis on the contribution of ecosystem services.

Natural ecosystems perform fundamental life-support services upon which human civilization depends. However, many people believe that nature provides these services for free and therefore, they are of little or no value. While we do not pay for them, we pay significantly for their loss in terms of wastewater treatment facilities, moratoriums on greenhouse gases, increased illnesses, reduced soil fertility and losses in those images of nature that contribute to our basic happiness. Little is understood about the well-being benefits of the natural environment and its ecosystem services. The interwoven relationship of ecosystems and human well-being is insufficiently acknowledged in the wider philosophical, social, and economic well-being literature. In this article, we discuss an approach to examine human well-being and the interactions of its four primary elements-basic human needs, economic needs, environmental needs, and subjective well-being-and ecosystem services.

Observational Verification of the Cumulative Resilience Screening Index (CRSI) Using Hurricanes, Inland Floods, and Wildfires From 2016 to 2019.

Users can apply three processes to develop confidence in decision-making tools like models and indices-validation, verification, and observation. The utility of the Cumulative Resilience Screening Index (CRSI) was demonstrated by combining the processes of verification and observation using real-world natural hazard events (i.e., hurricanes, inland flooding, and wildfires). The ability of CRSI to determine the counties most vulnerable to hazards and least likely to recover quickly from natural hazards is demonstrated using these natural hazard events from outside the original index construction data set. Using Hurricane Harvey and Hurricane Michael, the counties in Texas and Florida/Georgia, respectively, experiencing the most damage and the most extended recovery intervals were determined accurately. Similarly, the most vulnerable and least recoverable counties were correctly identified as those associated with the Great Louisiana Flood of 2016. Finally, three different types of wildfires in California were examined to determine the likelihood of recovery and the strength of pre-event planning. All models and indices developed for use by decision-makers should consider undertaking this verification or a similar validation operation to enhance user confidence.

The role of mathematical modelling in understanding prokaryotic predation.

With increasing levels of antimicrobial resistance impacting both human and animal health, novel means of treating resistant infections are urgently needed. Bacteriophages and predatory bacteria such as Bdellovibrio bacteriovorus have been proposed as suitable candidates for this role. Microbes also play a key environmental role as producers or recyclers of nutrients such as carbon and nitrogen, and predators have the capacity to be keystone species within microbial communities. To date, many studies have looked at the mechanisms of action of prokaryotic predators, their safety in in vivo models and their role and effectiveness under specific conditions. Mathematical models however allow researchers to investigate a wider range of scenarios, including aspects of predation that would be difficult, expensive, or time-consuming to investigate experimentally. We review here a history of modelling in prokaryote predation, from simple Lotka-Volterra models, through increasing levels of complexity, including multiple prey and predator species, and environmental and spatial factors. We consider how models have helped address questions around the mechanisms of action of predators and have allowed researchers to make predictions of the dynamics of predator-prey systems. We examine what models can tell us about qualitative and quantitative commonalities or differences between bacterial predators and bacteriophage or protists. We also highlight how models can address real-world situations such as the likely effectiveness of predators in removing prey species and their potential effects in shaping ecosystems. Finally, we look at research questions that are still to be addressed where models could be of benefit.

Differential lifespan impacts on veterans by war exposure in the First World War.

INTRODUCTION: There remains uncertainty around the impact of war on the lifespan of First World War (WW1) veterans. In particular, study comparison groups do not typically consider the 'healthy soldier effect'. METHODS: We obtained lifespan data on a random sample of 857 war-exposed New Zealand WW1 veterans and compared this with lifespans of a non-war military cohort (n=1039). This comparison was possible as the non-war-cohort arrived in Europe too late to participate in the war, allowing a 'natural experiment' that avoided the 'healthy solider effect'. RESULTS: The lifespan comparisons indicated lower mean lifespan in the war-exposed veteran cohort compared with the non-war veteran cohort (69.7 vs 71.1 years; p=0.0405). This gap persisted (range: 0.8-1.1 years) but was no longer statistically significant when only considering the non-Maori ethnic grouping (nearly all European/Pakeha personnel), when excluding additional deaths in the immediate postwar period up to 31 December 1923, and when excluding participation in any other wars. This was the case in both analysis of variance and Cox proportional hazards regression adjusting for year of birth and occupational status. Within the war-exposed cohort, there were suggestive patterns of increasing lifespan with increasing occupational status and military rank (eg, 69.5, 70.0 and 70.7 mean years as group-level occupational status progressively increased). There were also stark differences in lifespan of 8.3 years between Maori (Indigenous) and non-Maori veterans (p=0.0083). CONCLUSIONS: The pattern of reduced lifespan in war-exposed versus non-war-exposed veterans was compatible with a smaller previous New Zealand study with comparable methodology. Veterans who were Maori had significantly lower lifespans than non-Maori veterans. There are a number of feasible avenues to further improve this type of work with existing data sources.

Observed Changes in the Frequency, Intensity, and Spatial Patterns of Nine Natural Hazards in the United States from 2000 to 2019.

There is increasing evidence from across the globe that climate change results in changes in the frequency, location, and impact of natural hazards. Much of this evidence is conceptual, inferential, or simply assumed. To provide objective support to confirm these hypotheses, we constructed county-level time-series datasets (2000-2019) for nine natural hazards for the entire United States. Hazards considered for this study included hurricanes, tropical storms, landslides, wildfires, earthquakes, drought, inland flooding, coastal flooding, and tornadoes. Geospatial analysis techniques were used to calculate the percentage (range: 0-100) of land area in each county exposed to each natural hazard for all the years that hazard data were available. The best available data were acquired from publicly accessible sources. Cumulative distribution functions were calculated for each hazard in five-year intervals to test for statistically significant changes in distribution patterns across the five-year time periods using the Kolmogorov-Smirnov test. There were significant changes in hurricanes, tropical storms, and drought over the two decades; changes in tornadoes, landslides, and wildfires were not significant in terms of frequency, likely due to the site-specific nature of their occurrences. The intensity and spatial distribution and an emerging hot spot and spatial trend analyses and an emerging hot spot and spatial trend analyses were also completed (except for flooding events and earthquakes due to insufficient data). All datasets provide empirical support for earlier inferences concerning the connections between the hazards and climate change. Analyses showed apparent changes in the frequency and intensity of hurricanes, tropical storms, and drought-related to climate change factors. Internal and coastal flooding also demonstrated these connections, although the length of the dataset did not permit significant testing but shows significant hot spots and trending locations. Tornadoes, landslides, and wildfires showed significant hot spots and trending locations, but the specific locational nature of the data did not show significant changes in frequency. Earthquakes showed no significant changes over the time period.

The quantitative measurement of family quality of life: a review of available instruments.

BACKGROUND: Family quality of life (FQOL) has emerged as an important outcome of service delivery for individuals with disabilities and their families. The purpose of this review was to explore the disparity of scale development approaches between families with children with disabilities and families from other populations and identify strengths to serve as a source of recommendations to improve the measurements of FQOL in the disability field. METHOD: We conducted a keyword search of 25 databases. Sixteen measurement tools on FQOL, family well-being and family satisfaction currently used in the disability field, healthcare field and general family studies published in journals from 1980 to 2009 were included in the analysis. RESULTS: Three themes emerged from the detailed analysis and comparisons of the instruments: (1) description of the primary purpose and theoretical basis; (2) identification of the tool's respondents, domains, response formats and scoring strategies to assess family systems; and (3) summarisation of available psychometric information. CONCLUSIONS: As family researchers continue their mission to conceptualise and theorise about FQOL, they should also promote the refinement of FQOL measurements and consider the implications from family instruments used in the healthcare and general family fields from the following aspects: (1) domains of FQOL; (2) units of analysis; (3) response format; (4) scoring choice; and (5) psychometric evaluation.

Family quality of life: adaptation to Spanish population of several family support questionnaires.

BACKGROUND: The concept of family quality of life has emerged as a decisive construct in the last decades to improve the capabilities of families and to assess the outcomes of the services and supports they get. The goal of this research is to adapt three instruments to the Spanish population: the 'Beach Center Family Quality of Life Scale', the 'Beach Center Family-Professional Partnership Scale' and the 'Service Inventory'. These tools were originally designed by researchers from the Beach Center on Disability, University of Kansas, in order to obtain some input from the families of people with intellectual disability (ID) with regard to the attention they get from the early childhood intervention services. METHOD: The sample included a total of 202 families of children with ID, between 0 and 6 years old, all of them cared for at 13 early childhood intervention centres. Based on a confirmatory factorial analysis, we have explored the psychometric properties of the three scales administered to respondents. Statistical analyses were conducted with the spss software version 17.0 and the EQS software version 6.1 for Structural Equation Models. RESULTS: The results confirm that the factor structure of the 'Beach Center Family Quality of Life Scale', the 'Beach Center Family-Professional Partnership Scale' and the 'Service Inventory' adapted for the Spanish population fit the factor models proposed by the authors of the surveys. Consequently, the scales are ready to be used. CONCLUSIONS: The developed measures may serve as a foundation for good decision-making from practices and policies.

Investigating the relationship between environmental quality, socio-spatial segregation and the social dimension of sustainability in US urban areas.

This work is intended to assess the relationship between the three dimensions of sustainability (environmental, economic, and social) and residential segregation broadly across US urban areas. Multivariate indices of segregation and sustainability are created using data aggregated to 933 US Census Core-Based Statistical Areas (CBSAs). The relationship between segregation and sustainability (and dimensions, independently) is analyzed across the CBSAs using correlation and spatial analyses. Results show an inverse relationship between segregation and sustainability, where increasing urban segregation corresponds to decreases in sustainability. Social and economic dimensions of sustainability are negatively correlated with segregation while the environmental dimension is positively correlated. Spatial analysis reveals regional associations between the measures with most of the lower sustainability scores and higher segregation scores occuring mainly in the South. The findings demonstrate an inverse relationship between segregation and sustainability as well as between the environmental and social dimensions. These correlations indicate a need to consider inequalities, and the social dimension of sustainability more broadly, when planning urban revitalization efforts. Spatial scale is also imperative to understanding and improving the social outcomes for all members of the community.

Cost-Effectiveness Analysis of Stereotactic Ablative Body Radiation Therapy Compared With Surgery and Radiofrequency Ablation in Two Patient Cohorts: Metastatic Liver Cancer and Hepatocellular Carcinoma.

AIMS: To compare the cost-effectiveness of stereotactic ablative body radiation therapy (SABR) with radiofrequency ablation and surgery in adult patients with metastatic liver cancer and hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Two patient cohorts were assessed: liver oligometastases and HCC. For each patient cohort, a decision analytic model was constructed to assess the cost-effectiveness of interventions over a 5-year horizon. A Markov process was embedded in the decision model to simulate the possible prognosis of cancer. Data on transition probabilities, survival, side-effects, quality of life and costs were obtained from published sources and the SABR Commissioning through Evaluation (CtE) scheme. The primary outcome was the incremental cost-effectiveness ratio with respect to quality-adjusted life-years. The robustness of the results was examined in a sensitivity analysis. Analyses were conducted from a National Health Service and Personal Social Services perspective. RESULTS: In the base case analysis, which assumed that all three interventions were associated with the same cancer progression rates and mortality rates, SABR was the most cost-effective intervention for both patient cohorts. This conclusion was sensitive to the cancer progression rate, mortality rate and cost of interventions. Assuming a willingness-to-pay threshold of £20 000 per quality-adjusted life-year, the probability that SABR is cost-effective was 57% and 50% in liver oligometastases and HCC, respectively. CONCLUSIONS: Our results indicate a potential for SABR to be cost-effective for patients with liver oligometastases and HCC. This finding supports further investigation in clinical trials directly comparing SABR with surgery and radiofrequency ablation.