Sara S. Metcalf

Sharing the floodplain: Mediated modeling for environmental management

Complex ecosystems, such as the Upper Mississippi River (UMR), present major management challenges. Such systems often provide a range of ecosystem services that are differentially valued by stakeholders representing distinct interests (e.g., agriculture, conservation, navigation) or institutions (e.g., federal and state agencies). When no single entity has the knowledge or authority to resolve conflicts over shared resource use, stakeholders may struggle to jointly understand the scope of the problem and to reach reasonable compromises. This paper explores mediated modeling as a group consensus building process for understanding relationships between ecological, economic and cultural well-being in the UMR floodplain. We describe a workshop structure used to engage UMR stakeholders that may be extended to resource use conflicts in other complex ecosystems. We provide recommendations for improving on these participatory methods in structuring future efforts. In conclusion, we suggest that tools which facilitate collaborative learning, such as mediated modeling, need to be incorporated at an institutional level as a vital element of integrated ecosystem management.

Developing a Mobile Produce Distribution System for Low-Income Urban Residents in Food Deserts

Low-income households in the contemporary city often lack adequate access to healthy foods, like fresh produce, due to a variety of social and spatial barriers that result in neighborhoods being underserved by full-service supermarkets. Because of this, residents commonly resort to purchasing food at fast food restaurants or convenience stores with poor selections of produce. Research has shown that maintaining a healthy diet contributes to disease prevention and overall quality of life. This research seeks to increase low-income residents’ access to healthy foods by addressing spatial constraints through the characterization of a mobile market distribution system model that serves in-need neighborhoods. The model optimally locates mobile markets based on the geographic distribution of these residents. Using data from the medium-sized city of Buffalo, New York, results show that, with relatively few resources, the model increases these residents’ access to healthy foods, helping to create a healthier city.

Modeling Social Dimensions of Oral Health Among Older Adults in Urban Environments

In both developed and developing countries, population aging has attained unprecedented levels. Public health strategies to deliver services in community-based settings are key to enhancing the utilization of preventive care and reducing costs for this segment of the population. Motivated by concerns of inadequate access to oral health care by older adults in urban environments, this article presents a portfolio of systems science models that have been developed on the basis of observations from the ElderSmile preventive screening program operated in northern Manhattan, New York City, by the Columbia University College of Dental Medicine. Using the methodology of system dynamics, models are developed to explore how interpersonal relationships influence older adults’ participation in oral health promotion. Feedback mechanisms involving word of mouth about preventive screening opportunities are represented in relation to stocks that change continuously via flows, as well as agents whose states of health care utilization change discretely using stochastic transitions. Agent-based implementations illustrate how social networks and geographic information systems are integrated into dynamic models to reflect heterogeneous and proximity-based patterns of communication and participation in the ElderSmile program. The systems science approach builds shared knowledge among an interdisciplinary research team about the dynamics of access to opportunities for oral health promotion. Using “what if” scenarios to model the effects of program enhancements and policy changes, resources may be effectively leveraged to improve access to preventive and treatment services. Furthermore, since oral health and general health are inextricably linked, the integration of services may improve outcomes and lower costs.

Simulating the effects of social networks on a population’s hurricane evacuation participation

Scientists have noted that recent shifts in the earth’s climate have resulted in more extreme weather events, like stronger hurricanes. Such powerful storms disrupt societal function and result in a tremendous number of casualties, as demonstrated by recent hurricane experience in the US Planning for and facilitating evacuations of populations forecast to be impacted by hurricanes is perhaps the most effective strategy for reducing risk. A potentially important yet relatively unexplored facet of people’s evacuation decision-making involves the interpersonal communication processes that affect whether at-risk residents decide to evacuate. While previous research has suggested that word-of-mouth effects are limited, data supporting these assertions were collected prior to the widespread adoption of digital social media technologies. This paper argues that the influence of social network effects on evacuation decisions should be revisited given the potential of new social media for impacting and augmenting information dispersion through real-time interpersonal communication. Using geographic data within an agent-based model of hurricane evacuation in Bay County, Florida, we examine how various types of social networks influence participation in evacuation. It is found that strategies for encouraging evacuation should consider the social networks influencing individuals during extreme events, as it can be used to increase the number of evacuating residents.

Public Health Support for the Health Home Model

The author reflects on the implementation of the home health model of medical care in the U.S. She suggests that the current medical, dental and social care systems in the U.S. are difficult to navigate and create pain and suffering for older patients and burnout for care providers. She argues that the health home approach places an emphasis on promoting health and well being and that the health home model of treating older people should receive support.

Strategic directions for agent-based modeling: avoiding the YAAWN syndrome

In this short communication, we examine how agent-based modeling has become common in land change science and is increasingly used to develop case studies for particular times and places. There is a danger that the research community is missing a prime opportunity to learn broader lessons from the use of agent-based modeling (ABM), or at the very least not sharing these lessons more widely. How do we find an appropriate balance between empirically rich, realistic models and simpler theoretically grounded models? What are appropriate and effective approaches to model evaluation in light of uncertainties not only in model parameters but also in model structure? How can we best explore hybrid model structures that enable us to better understand the dynamics of the systems under study, recognizing that no single approach is best suited to this task? Under what circumstances – in terms of model complexity, model evaluation, and model structure – can ABMs be used most effectively to lead to new insight for stakeholders? We explore these questions in the hope of helping the growing community of land change scientists using models in their research to move from ‘yet another model’ to doing better science with models.

A Systems Perspective for Dental Health in Older Adults

As the population of older adults in the United States expands with the aging of the baby boom generation coupled with longer life expectancies, the need for coordinated and cost-effective health policies becomes more acute. Oral health promotion and care may help prevent potentially debilitating oral conditions that can cause significant discomfort, affect social interaction, and reduce the ability to properly masticate, thereby affecting nutrition. Nonetheless, developing effective oral health interventions for older adults is challenging, owing partly to the complex set of causal pathways that are involved and the time delays that accrue over a life course. Drawing upon the methodology of system dynamics, a causal map was developed and is presented here to illustrate how relationships at the individual and interpersonal scales influence dental health outcomes among older adults. Specifically, chronic illness and nutrition-related dynamics are implicated in dental health, as is the availability of social support and oral health promotion. This systems perspective reflects shared knowledge among an interdisciplinary research team about the dynamics of dental health through a set of reinforcing feedback loops that are likely to be induced with age.

A Community-Based Oral Public Health Approach to Promote Health Equity

OBJECTIVES We explored the interrelationships among diabetes, hypertension, and missing teeth among underserved racial/ethnic minority elders. METHODS Self-reported sociodemographic characteristics and information about health and health care were provided by community-dwelling ElderSmile participants, aged 50 years and older, who took part in community-based oral health education and completed a screening questionnaire at senior centers in Manhattan, New York, from 2010 to 2012. RESULTS Multivariable models (both binary and ordinal logistic regression) were consistent, in that both older age and Medicaid coverage were important covariates when self-reported diabetes and self-reported hypertension were included, along with an interaction term between self-reported diabetes and self-reported hypertension. CONCLUSIONS An oral public health approach conceptualized as the intersection of 3 domains-dentistry, medicine, and public health-might prove useful in place-based assessment and delivery of services to underserved older adults. Further, an ordinal logit model that considers levels of missing teeth might allow for more informative and interpretable results than a binary logit model.

Enhancing implementation science by applying best principles of systems science

BackgroundImplementation science holds promise for better ensuring that research is translated into evidence-based policy and practice, but interventions often fail or even worsen the problems they are intended to solve due to a lack of understanding of real world structures and dynamic complexity. While systems science alone cannot possibly solve the major challenges in public health, systems-based approaches may contribute to changing the language and methods for conceptualising and acting within complex systems. The overarching goal of this paper is to improve the modelling used in dissemination and implementation research by applying best principles of systems science.DiscussionBest principles, as distinct from the more customary term ‘best practices’, are used to underscore the need to extract the core issues from the context in which they are embedded in order to better ensure that they are transferable across settings. Toward meaningfully grappling with the complex and challenging problems faced in adopting and integrating evidence-based health interventions and changing practice patterns within specific settings, we propose and illustrate four best principles derived from our systems science experience: (1) model the problem, not the system; (2) pay attention to what is important, not just what is quantifiable; (3) leverage the utility of models as boundary objects; and (4) adopt a portfolio approach to model building. To improve our mental models of the real world, system scientists have created methodologies such as system dynamics, agent-based modelling, geographic information science and social network simulation. To understand dynamic complexity, we need the ability to simulate. Otherwise, our understanding will be limited. The practice of dynamic systems modelling, as discussed herein, is the art and science of linking system structure to behaviour for the purpose of changing structure to improve behaviour. A useful computer model creates a knowledge repository and a virtual library for internally consistent exploration of alternative assumptions.ConclusionAmong the benefits of systems modelling are iterative practice, participatory potential and possibility thinking. We trust that the best principles proposed here will resonate with implementation scientists; applying them to the modelling process may abet the translation of research into effective policy and practice.

Linking models of human behaviour and climate alters projected climate change

Although not considered in climate models, perceived risk stemming from extreme climate events may induce behavioural changes that alter greenhouse gas emissions. Here, we link the C-ROADS climate model to a social model of behavioural change to examine how interactions between perceived risk and emissions behaviour influence projected climate change. Our coupled climate and social model resulted in a global temperature change ranging from 3.4–6.2 °C by 2100 compared with 4.9 °C for the C-ROADS model alone, and led to behavioural uncertainty that was of a similar magnitude to physical uncertainty (2.8 °C versus 3.5 °C). Model components with the largest influence on temperature were the functional form of response to extreme events, interaction of perceived behavioural control with perceived social norms, and behaviours leading to sustained emissions reductions. Our results suggest that policies emphasizing the appropriate attribution of extreme events to climate change and infrastructural mitigation may reduce climate change the most.Human behaviour is an important driver of emissions. A system-dynamics model that couples a psychological model of behaviour with a model of emissions and climate change shows that behaviour can influence global temperature in the year 2100 by up to 1.5 °C.